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By Outlaw56 - 10 Years Ago
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Im lookin for good gas mileage, four barrell, easy to rebuild and low maintainance carberator for 272/292 range Y block. Something easy to find used that I can put a kit in and wont break the bank. Just a daily driver type carberator with simplicity and quality. I know you guys will give me some good recommendations. Thanks for all your help.
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By Dobie - 10 Years Ago
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I run an Edelbrock 500 cfm Performer on my 292. It worked great out of the box with no tuning needed other than idle mixture. Edelbrock bought the patents for the Carter AFB and made a few improvements and sells them as the Performer series. Depending on which manifold you have you may need an adapter (readily available from Speedway and others), and I suggest a 1 or 2 inch phenolic spacer. The spacer will prevent hot start issues due to the cast iron manifold heating the carb enough to boil our ethanol-laden gas out of the float bowl, and provides a very crisp throttle response.
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By Outlaw56 - 10 Years Ago
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Im hoping to get the ECZ 9425B so I will have a bigger window for options. I think if I go that route, I need to consider swapping out the distributer too, correct? Thanks Dobie.
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By Dobie - 10 Years Ago
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Not only do you need to consider it, it's a MUST. The Loadamatic dizzy won't work with any carb other than the original style. The '57 and later unit for full sized cars and trucks will have centrifugal and vacuum advance mechanisms. The Loadamatic has no centrifugal components.
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By gekko13 - 10 Years Ago
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On a mild Y-block, a Ford/Autolite "cracker box" (4100) carburetor is really hard to beat. They are easy to work on, not prone to leakage and just plain work. They also keep your FoMoCo more authentic, IMO. Parts are readily available form multiple sources which keeps costs down.
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By Pete 55Tbird - 10 Years Ago
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Darrell, Whatever 4BBL that you decide on will require you to rig up some sort of throttle linkage. That can be an issue.
As you have been told the 56 and earlier Ford distributors were ONLY VACUUM ignition advance and need a carb designed to work in that system.
A lot of cars only have mechanical ignition advance and that works OK. The vacuum advance is only in operation during steady throttle high manifold vacuum ( cruise ) and adds MPG on the cars whose distributors have both mechanical AND vacuum ignition advance.
All the 4BBL carbs except Holley that are double pumpers will have vacuum operated secondaries and will be user friendly. Pete
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By Outlaw56 - 10 Years Ago
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All great information. I am getting a Z9425B from Marc which will go on the shelf. Until then, I will get a spacer between the intake I have now and the dizzy and hook up my PVC. I have another 292 that I already did the upgrade to an edelbrock and new distributer, but I have never started it. When I get ready to rebuild the 272, I will take the B intake off the shelf, replace the distributer, and have it bored for a 292. Three builds in progress. I also have a little 239 that was running sweet when I picked up the truck. That is going out the door. I hate to scrap it, but I can probably get $100 for it if no one wants it. I will try locally on Craigs list before I scrap it.
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By Talkwrench - 10 Years Ago
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Good ol' 465 Holley would be fine also [as well as 390, 450] very tuneable.. Buy new , cheap, done!
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By Outlaw56 - 10 Years Ago
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Thanks Wrench
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By PF Arcand - 10 Years Ago
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Further on the Ford/Autolite carb recommendation, best to go with the 1.08 version over the 1.12 according to those that know. Also avoid the later smog models used on big blocks. In comparison tests of several carbs, done by our moderator Ted, the 1.08 scored well, only bested by the later Holley 465cfm. As mentioned, linkage can get complicated with some carbs that will fit otherwise..
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By stuey - 10 Years Ago
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i seem to recollect Mr Mummert getting good results from from a Summit 4100 replica except the fuel inlet tubes leaked
stuey
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By PF Arcand - 10 Years Ago
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Stuey: Yes, your correct..however that was on a high performance stroker engine, Kevin just wants to pep up a stocker a bit..so it may or may not be a good choice... ?.
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By The Horvaths - 10 Years Ago
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The Holley 1848-1 is designed for modest-displacement Ford engines.
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By Ted - 10 Years Ago
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If it's simply a matter of keeping the costs down, then the 600 cfm Holleys are plentiful and reasonably easy to kit. The nice part about a vacuum secondary carb is that they are self compensating when being put on an engine that's on the small side versus the size of the carb. If opting for a new carb, then the 525 Street Demon Jr, the 500 cfm Edelbrock, or the 450 cfm List #1848-1 Holley are all suitable carbs for most Y engines.
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By stuey - 10 Years Ago
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point taken re stroker engine
its how i learn
stuey
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By 55vickey - 10 Years Ago
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I'm running a 465 Holley on my mildly built 272, runs great and I haven't touch it since I put it on, over 5 years ago.
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By charliemccraney - 10 Years Ago
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RE the summit carb, it's not a "performance" carb by any stretch. It should work on a stock or mild motor, too. It just so happens that it worked well on a stroker. It seems to be a pretty good carb.
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By ChrisS. - 10 Years Ago
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I fitted a Holley 390 to my '55 Vicky which has a stock 312. It's been on a couple of years and has transformed my car from a thirsty, temperamental, unreliable old beast to something dependable and a delight to drive. I'm very pleased with it!
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By Outlaw56 - 10 Years Ago
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This is the distributer I believe came off a 1962 F-100 Unibody stock 292 with two barrell manifold and carb. I have an ECZ9425B intake so I can block off the road draft tube on my 1956 Stock 272. To move forward with the removal of the road draft tube, understand I must change the distributer if I want to have more options for carb choices. The distributer is CT3F-12127-K. It has the ford script logo and 3ED below the first part number. Hoping I have everything right so far except the carberator and that the choices I have made have given me lots of options to find a good used carb I can rebuild.
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By PF Arcand - 10 Years Ago
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Darrell: It's a shame to scrap a good running 239. May I suggest to put it in our sites Classifieds?.. Also there is a 54 Ford Club of America, run by a Tom Hoskins at 817-466-8088 in Arlington Tx., or at- HoskinsTom@yahoo.com
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By Outlaw56 - 10 Years Ago
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I hear what your saying. Its been cleaned and painted....nice little motor.
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By 2721955meteor - 10 Years Ago
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I went onto holley store on ebay,they have refurbished warrantee returns,bought a 550 cfm for150.00 warrantee included. works great on my 292 ranchero
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By Outlaw56 - 10 Years Ago
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Thats good to know! I will check it out. Im guessing a rebuildable carb would be $50 and a kit around $60,,,so thats not bad at all if it saves me the time of doing a rebuild.
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By Talkwrench - 10 Years Ago
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Not a bad idea if you can get one from Holley. I would be vary sus' on getting a second hand one and you try to rebuild yourself been down that road people fu*( with them too much . If your on the east coast [USA] see Phil at RPM Ind. He supplied a second hand 450 to my spec charged me $250 and I swear it looked new out of the box!.
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By Outlaw56 - 10 Years Ago
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Sounds like I have more options than I ever imagined. Thanks for all the input, I have read and filed it all.
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By Y block Billy - 10 Years Ago
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I wiil back up Charlie and Mummert that the Summit Ford style carb is a great carb for cheap money, I have put 2 on customers cars and they performed crisp and sweet through all rpm ranges, not a stumble or miss anywhere, they get my thumbs up!
And Chris S, 55's did not come with stock 312's so you do not have a stocker.If you think it is the stock motor look at the first letter of the VIN on your door post U=272 M=292 and I can't remember the 6 cylinder code off the top of my head, not sure if there were many or any 292's put in cars, I think most were only in Birds.
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By lyonroad - 10 Years Ago
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Y block Billy (4/2/2014)
, I think most were only in Birds.
And Mercurys and in Canada Monarchs as well.
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By speedpro56 - 10 Years Ago
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1955 ford V8s were 272 and 292s with the vast majority being 272s. The 292s in 55 were the interceptors bought thru law inforcement or if you were friends with a dealership owner who would fudge the cause.
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By Outlaw56 - 10 Years Ago
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Y block Billy (4/2/2014)
I wiil back up Charlie and Mummert that the Summit Ford style carb is a great carb for cheap money, I have put 2 on customers cars and they performed crisp and sweet through all rpm ranges, not a stumble or miss anywhere, they get my thumbs up!
And Chris S, 55's did not come with stock 312's so you do not have a stocker.If you think it is the stock motor look at the first letter of the VIN on your door post U=272 M=292 and I can't remember the 6 cylinder code off the top of my head, not sure if there were many or any 292's put in cars, I think most were only in Birds.
Billy, I checked out Summit, but I dont see anything listed under Ford style carb. Can you paint me a picture?
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By charliemccraney - 10 Years Ago
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http://www.summitracing.com/search/part-type/carburetors/number-of-barrels/4/cfm/600?SortBy=BestKeywordMatch&SortOrder=Ascending&keyword=summit%20racing%20street%20%26%20strip%20carburetors
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By Outlaw56 - 10 Years Ago
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Thanks Charlie. Looks like same carb, one new and one remanufactured which is probably good as new.
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By Outlaw56 - 10 Years Ago
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charliemccraney (4/3/2014)
Hey Charlie, Im going to pull the plug and order the Summit Carb Part # SUM-M08600VS or the Edelbrock 500 performer for my 272 (Daily driver stock engine). Im having a hard time making up my mind which way to go. Anyone else who can offer some guidance, please chime in.
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By charliemccraney - 10 Years Ago
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I have no experience with the summit carb but based on what others have experienced, I would not hesitate to try it.
I find the Edelbrocks to be a pita to tune and they just are not generally as tunable. Pita doesn't mean hard. It's just that metering rods only get you so far and when it gets to the point that you need to swap jets, there is a lot of screws and clips and little things that get lost easily to be removed and it is made less pleasant when the tuning is being done on a hot engine - I'd rather have a Holley style carb when it comes to tuning - much faster jet changes, fewer parts to loose and less time handling hot parts. I also had an issue with my 600 Edelbrock where the secondary air valve did not work correctly with my combo. That can also be worked around by grinding on a counter weight but on a Holley you just swap a spring and you're good. Most of the time there does not seem to be a problem with that, however. Of course Edelbrock now have the AVS with the adjustable secondary air valve but it costs more.
Of the two options I'd go with Summit simply because I haven't used one yet.
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By pegleg - 10 Years Ago
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I run an Edelbrock 1405 on my F code. Seems to work pretty well. Very consistent at the strip, but not legal for pure stock. I'd disagree with Charlie about the tuning, with the instruction manual they provide it's a piece of cake. But then so are the Holleys. Be careful buying a used Holley, many of the older ones had Quality problems.
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By Outlaw56 - 10 Years Ago
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I have not ruled out a Holley 600, just have no experience with them. But I would still consider it with the two previous options. I see some factory rebuilt holleys on ebay (refurbished returns) but I dont know where to look as far as model numbers or carbs that would fit my manifold. I swapped my stock manifold out with an ECZ9425B to work with a new carb and get away from the "dizzy" distributer. dI just want a new or refurbished carberator (electric choke) that will run good and give me good performance. There are too many model numbers on Holleys, I dont even know where to start looking.
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By pegleg - 10 Years Ago
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If you were to buy a "Factory" unit from holley, you probably be good. It's the Fly by night operators on Ebay that you'd want to be careful with. I've heard good things about the Summit carbs as well, IO would not be afraid to try one of them.
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By charliemccraney - 10 Years Ago
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If you go Holley, 570 Street Avenger,
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By Outlaw56 - 10 Years Ago
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Another concern is over carbing my 272. If I remember correctly, Ted said the 600 cfm series would be fine. I will be sure if I get anything off ebay its Holley direct. Will also add the Holley 570 Street Evenger to my list of options. Thanks!
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By Chuck - 10 Years Ago
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I know I'm new here, but I'd like to add some insight based on experience:
The old formula for carburetor sizing was displacement x RPM x volumetric efficiency / 3456 = design CFM flow rate. Stock motors usually have a volumetric efficiency of .75, and 5000 RPM is a good default value. Using these variables, a stocker 272 will flow about 300 CFM. On the other end of the scale, a hotted up 312 spinning north of 6000 RPM will flow about double that with a VE approaching 100%, or 1.
Now here's where it gets tricky. 2 bbl carbs are flow rated at 3 inches of mercury, and 4 barrel units are rated at 1.5 inches. On top of that, stock carburetors rarely flow at rated value - it's usually less than that. To overcome these variables, I typically take the as-calculated design air flow and add 25%, multiplying by 1.25. Take that number and select the next higher carburetor size and you'll be fine - or you can go down one size and have better streetability.
As Ted said, a vacuum secondary carburetor is the way to go in the selection process. The vac secondaries will maintain a consistent vacuum signal - which is the power source for the analog computer that is a carburetor. A mild 272 will run very nicely on a Holley 390, whereas a 292 would favor a slightly larger carb, especially if it has dual exhaust or a mild cam.
If you go too far in the carburetor sizing process, you run into a characterization issue, which is a fancy way of saying the carburetor loses the ability to control the air fuel ratio as the throttle plates are opened. The vacuum signal drops to near zero along with flow through the venturis. At this point, fuel drops out of suspension and puddles in the manifold - making for very erratic operation. There are work-arounds for this, but they're either band-aids or part of and expensive custom carburetor build. By the time the carb is 75-80% larger than design flow - it's too big, in my opinion.
Hope you guys find this helpful.
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By speedpro56 - 10 Years Ago
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A 390 to 465 cfm holley is plenty for a 272 even when warmed up a bit with a better cam and intake these two carbs should work fine but the 390 may need to be jetted up a few numbers from stock. These carbs as Charlie said are easy to tune and run great. A 570 avenger should work well but don't won't to go too big and start losing the bottom end torque from take off to 4500 or so RPMs.
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By Outlaw56 - 10 Years Ago
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I just read a very extensive post on the Summit 4100 Replica over on the FTE Forum. From what I gathered, you can get kits for that carb to build it up, but you cant get kits to build it down. Since I consider a stock 272 on the down side, along with my understanding the Summit 4100 Replica is on the rich side...........Im thinking it might be a little too much carb for my application. My other concern was the terrible gas mileage one member got with serious time and energy put into making that carb work for him.Perhaps the Summit 4100 Replica is a better application for the beefed up 272's, or 292's with option of kits to build up? The other thing that got my attention is the allegation its made in China?
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By Outlaw56 - 10 Years Ago
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Whats the difference between a Holley 525 Street Demon Jr and a Holley 570 Avenger? Is one better suited than the other for a stock 272 with a post 57 intake and newer distributer? Keep in mind all I know about carburators is where the mount on the engine. Never rebuilt one or did any "tuning". I have the Edelbrock 500 Performer that is going into a 292 that will be built up towards a 312 if I can collect the parts, otherwise, just all I can get out of the 292. Maybe I should use the Edelbrock on my 272 and get something else when I get the 292 further along?
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By Campsite - 10 Years Ago
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Two Add my two cents on this subject. On my 312 I was looking thru the Holley Book. And found the number for the replacement Carb. It was for a 289 HIGH PERFORANCE, Not much of Difference between the two. I have had it on the 312 for three years now, works great. My 312 is built to Run hard,
I can supply the number if needed. Bob
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By miker - 10 Years Ago
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Carbs are always a source of varying opinions. I have to go with Frank on the tuning part. I've run 1405 Edelbrocks on stock 292's, supercharged 320cid strokers, 265 and 350 scrubs, they all just worked. The tuning manual looks a bit confusing, but once you find the right page and graph, it's pretty simple. Change the rods, pull the top and do the jets, no fuel all over. All the secondary's have stayed stock, even with the blow thru supercharger. Only had to change the rod springs on the blow thru setup. I especially like the low rpm-part throttle performance. I'm told the new Holley's are better there than they used to be. Edelbrocks will work with minor mods no matter what you do to the motor, short of all out racing. And maybe there, too.
I've also had a couple Holley's that drove well, and a couple Q -Jets. The Q's I had done by pro's, I have no clue how they work, and my attempts to tune them proved it.
The only problem I've had, both Holley and Edelbrock, is getting the electric choke to work right in the summer. On a good, cold day, fine. But I never seem to be able to reset them right for summer. The manual choke solves that.
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By charliemccraney - 10 Years Ago
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The 525 Street Demon JR is technically a Demon carburetor but they are not around as their own company anymore; Holley owns the brand now. That is a good carb, too.
What I understand about the Summit carb is that it uses Holley parts, so tuning should be a breeze and parts to do so should be easy to get. I don't really understand the building up and building down thing. The made in China part would bother me, if it is true. I've gotten to a point where I try not to buy made In China if at all possible, even if it is a quality product.
I think any one of them will do the job just fine.
When I switch from My Edelbrock 600 to the Holley 570, it was a night and day difference from idle to 6000rpm and it got better mileage. That was with only a couple hours of tuning after the initial installation vs many, many hours of trying different things with the Edelbrock, before I learned about the air valve "fix." This isn't a Holley is better than Edelbrock statement. I think what really is happening is that the Street Avenger series is a modern carb whereas the Edelbrock is not and the new tech in the SA allows it to work better.
With any of these, you should expect to tune it. They will all probably advertise some version of "guaranteed to work out-of-the-box" and they probably will but working out-of-the-box and properly tuned can be two different things. It could turn out that out-of-the-box is perfect, but probably not. Do your best to pick something that is inline with the goal of the engine. Don't go too big, and don't take a smaller one that you will need to replace with a bigger one in the not too distant future. With every one of these carbs, you should be able to email the manufacturer to find out what they recommend for your application. They know their carbs better than anyone else and can tell you if it will be a good fit or not.
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By Outlaw56 - 10 Years Ago
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My reference to building up or down was with regards to the carberator out of the box and changing it with a kit to make it perform better for a higher or lower performance engine. I got the impression the Summit 4100 Replica might be best suited out of the box for a souped up 272 or 292 and not so great for a stock 272. When the thread poster tried it on his stock 272, he thought it was too rich. He contacted Summit to get the parts to tune it down, he was told the only kits available were to tune it upwards for higher performance engines. Hope that makes sense. Of course the made in China was just repeating what I read on another forum but has never been confirmed.
With no experience in these carbs, I can say I am impressed with the Edelbrock Performance 500 I have for my 292. Problem is I dont have nothing to compare it to.
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By steinauge - 10 Years Ago
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I am using an Edelbrock 600 on my mildly modified 292 with zero issues, just bolted it on,set the pilot screws and idle speed.I have used the Summit carb both 600 and 750 CFM versions on a couple of other engines with really excellent results. I would buy either again,but would probably lean toward the Edelbrock just because I had such good results with Carter AFBs for so long.
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By Ted - 10 Years Ago
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Here’s a picture of a Summit 750 cfm carb that was recently installed on a 303” Y with stock heads and iron intake. It made 315 HP on the dyno and runs great in the car. Only change to the carb was fattening up the secondary jetting three numbers.
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By Outlaw56 - 10 Years Ago
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From what I have read (no actual experience), its pretty easy to over carburate a stock 272. The Edelbrock 500 Performer Series is leaning in the direction of "overkill", but it will work. If the stock engines future includes a more aggressive camshaft, bigger pistons, increased air flow with ram horns and increasing exhaust pipe and muffler diameter, I would hope the 272 would grow into the 500. Edelbrock also makes the 500 in the Thunder Series which I believe is the same as the Performer but includes adjustable secondaries. The Edelbrock 500 Thunder Series is the one I have brand new in the box which I had purchased several years ago for my 292. That 292 is going to get rebuilt one day and I am wondering if I should get a 600 for it and use the 500 in the 272. Any thoughts? Neither of these Y blocks is going to be for hot rodding, just daily drivers. I'm hoping to get good running engines with good gas mileage. Maybe the 500 series will be good for both?
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By Ted - 10 Years Ago
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Outlaw56 (11/4/2014)
........ Any thoughts? Neither of these Y blocks is going to be for hot rodding, just daily drivers. I'm hoping to get good running engines with good gas mileage. Maybe the 500 series will be good for both? It’s difficult to go wrong with a vacuum secondary carb. The secondaries on those are good at only opening the amount required by the engine. Whereas a mechanical secondary carburetor is very rarely at the optimum sizing for an engine (either too big or too small), being oversized on a vacuum secondary carb will always insure the engine will get the amount of air it wants.
I run a 525cfm Road Demon Jr. on my own 272 now and it runs fine. I’ve also run a 780 Holley on the same engine but drivability at low rpms was not as good as it seemed to be more sluggish right off of idle. Full throttle performance was fine though with the vacuum secondaries. I borrowed a friend’s 600 cfm Edelbrock carb and it had a noticeable flat spot or hesitation right off of idle compared to the 500 cfm Carter that I use to run on the same engine.
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By Outlaw56 - 10 Years Ago
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Thanks Ted. If I plan on a mid range build for the 272 and a upper end range build for the 292, would you recommend 500 for the 272 and a 600 for the 292? I really like the idea of the Edelbrock becasue If I understand correctly, they are easier to tune and adjust than other options.Since I already have the 500 Thunder, Im thinking I should use it on the 272 and order a 600 for the 292? Not sure about the 600 based on your experience and the "flat spot". Wonder if a 500 or 700 would work for a hopped up 292.
I just called Edelbrock Tech. They recommend the 500 for anything below 300ci. The 272 won't be an issue. The 292 could be with a little modification. I think Im going to put the 500 on the 272 and order something bigger for the 292. Is should not take much modification to get the 292 above 300.
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By charliemccraney - 10 Years Ago
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The Edelbrock 600 worked fine on my warm 292, other than that air valve problem, which you probably won't have. Since you mentioned Thunder, I assume you mean the Thunder AVS, you absolutely should not have that problem because it is adjustable.
That said, if Edelbrock recommended the 500, that may be the one to go with. Did you tell them your plans or just that it is 292ci?
Another thought is since you will already have a 500, you can try it on the 292 and see if you like it. If you are satisfied with the performance then get another 500.
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By Outlaw56 - 10 Years Ago
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Hey Charlie, I did tell Edelbrock Tech I would eventually want a medium build on the 272. They said anything below 300 would be fine with the 500 Thunder AVS I already have. I assumed anything above 300 would get the 600. Ted said he had experienced a flat spot on the the Edelbrock 600 he borrowed from a friend to test on his 272. My 272 will be the first truck I have running, so as long as I already have the 500, Im thinking I will try it on the 272. When it comes time to get another carb for my 292, I will maybe bump up to a 600 or 700. My other concern is in the 292, I have installed an AOD. I dont think the 500 Thunder AVS I have now is set up for the AOD Cable. Really not sure how all that works, but next carb I buy I will know more about what I need for the AOD cable hook up. If I understand correctly, some carburators come with the option of a throttle cable connect for an AOD and some dont?
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By charliemccraney - 10 Years Ago
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What I mean is when it comes time to get a carb for the 292, you can use the 500 off of the 272 to see how it does. That way it takes some guessing out and you can decide on a 500 or 600 for the 292 more easily.
Regarding the throttle linkage, they offer conversion kits for various transmissions so they probably have something that will work for the AOD.
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By Outlaw56 - 10 Years Ago
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ok, got you this time. Makes sense, lol. Geze how did I miss that the first time. Thanks Charlie!
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By pegleg - 10 Years Ago
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Charlie,
I have zero experience with the 570. Are the primaries smaller on it than a comparable Edelbrock 1405 ?. That could explain the better response at lower rpm's with a small inch motor. That was always the hard part of trying to make a 600 anything work o a 272 or under 300 inch anything. I also don't have any experience with the Edelbrock 500 on anything. I can only relate to the 312-600 combo, and we know that works pretty well. c
I suspect that a lot of our "opinions" on this subject arise from one example (like mine) and really aren't worth much on another combination. Example, My 65 GTO came with a Carter AFB. Same carb as the Edelbrock of today. As soon as I modified the car it became undriveable. swapped a 750 Holley on it and it was all better. Therefore I don't like AFB's / Edelbrocks. Well i was wrong!
On the street at least they are very good. I had some bad luck with Holley 10-15 years ago and became set against them. They've cleaned up their act and now are very good again. Careful about opinions!!
Outlaw: Check Lokar's cable setup for the AOD. It works very well, had one on my 408 Ranger P/U.
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By Outlaw56 - 10 Years Ago
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My problem is lack of experience. I get on these forums where there are so many members who know so much more than I do and have so much more hands on experience. Without the input of the forum, I would be so so lost. My decision to go with the Edelbrock Performer or Thunder 500 on my 272 was based on several facts. First, I already had a new in the box Edelbrock 500 Thunder AVS that I had previously choosen for my 292 with a future build. Probably 300 or above. Then I came across another truck and drug it home. That has a 272 so I was faced with the same option again. It had the two barrell intake and a dizzy. I swapped them out for a B manifold and post 57 Distributer. Not realizing at the time the trend seems to be "over carbing" these engines.
After considerable more research and forum input, I have to face this decision again. Edelbrock out of the box is a good choice for me because I dont have to remove it to make adjustments and they seem much easier for a beginner like myself. I would like to try something else, but am not wanting to put the patience into learning carberation from ground zero. That left me with the opportunity to consider another carb for the 292 and use the 500 Thunder for my 272. Had I known before what I know now, I may have chosen the Performer over the Thunder, but I dont think I can get hurt because they are the same with exception the Thunder has more adjustment options.
During this process, I also came across some information that talked about some carbs not working with an AOD becasue they do not have the auto transmission shift cable that hooks to the carb. When I bought my Edelbrock Thunder, I did not pay any attention to whether or not it was set up for AOD. Its quite possible I can get it as an add on, but since Im wanting to get the 292 above 300, it would be a good time to consider a 600/700 with the AOD Cable set up. I have to figure out exactly what Im going to do with the 292 before I select a 600 or 700. I certainly have the option to throw my 500 on it and take it for a test drive before I make another choice. By then, I may even go with a holley? Right now, Im looking at that new black powdercoated Edelbrock.
I would be in big trouble if it were not for all the input I get from this forum.
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By charliemccraney - 10 Years Ago
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Frank,
I don't know how the primaries compare between the two carbs. However, one thing I do recall is that the 500 and 600 cfm Edelbrocks have the same primary and secondary bores and venturi diameters, as indicated in the tuning manual. So there's more to it than those specs alone.
In my experience, the better response was throughout the entire range, not just low rpm, only verifiable by my butt, though. Another problem I had with the Edelbrock is during hard cornering, the truck would sputter and sometimes stall. I never changed the float level from the factory setting. That could have fixed that problem but the floats were set to the by-the-book spec. And how hard was I really cornering in a 50 year old truck with horse and buggy suspension? I couldn't imagine that on a vehicle that actually handles. I'll definitely try it again on some engine in the future since I have it and I know a lot of people have success with them and I believe in second chances but as my first experience with an Edelbrock, I'm not impressed.
The tuning manual that comes with the Edelbrock is phenomenal. Most of the information can be applied, in general, to any carburetor, so from that perspective, it absolutely is a great carburetor if tuning is new to you. It tells you specifically how to tune the Edelbrock and from that experience, you have an analog for tuning most others.
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By Outlaw56 - 10 Years Ago
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Im taking notes....when I bolt up my 500 to my 272 you can be I will be reviewing this post. Maybe after a little tinkering I will try something more complicated.
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By miker - 10 Years Ago
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Charlie,
While I think Frank hit the nail pretty well, try lowering the float a little on the Edelbrock, if you go to run it again. Mine did that when it "tilted". We use a lot of "rolling" curbs in my area, so turning into a driveway was enough to cause it. Made me miss the center hung floats in the Holley's. Didn't seem to take much, and didn't lean it out too far.
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By Outlaw56 - 10 Years Ago
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Frank, I actually have the Lokar cable that came with my AOD. I just dont know how or where it hooks to the carb and what I have to be looking for on the carberator I purchase.
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By PF Arcand - 10 Years Ago
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It's always interesting to read about carb recommendations.. Having hung around car guys & race tracks some, the opinions, particularly on size, are often, if such & such is good, then "Bigger is better.!" And the same is generally true of cam shaft recommendations. Ted Eaton has pointed out that big carbs can often be tuned to work on small engines o.k. But, unless you have some carb knowledge & patience & in the case of a new carb, are willing to except that the vendor will balk at taking it back, after you've tinkered with & messed it up, best to stay on the conservative side in selecting a carb for a smallish engine...
P.S..- If I recall this reference material has been posted here also, but was originally printed in Y-Blk Magazine, issue # 97, in 2010. Briefly it was a test of 16 carbs on Ted Eaton's mildly modified 322" test mule. In short, two of the top 5 carbs tested, were under 500 cfm.. a Ford Autolite 1.08 & a Holley 465...
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By Outlaw56 - 10 Years Ago
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Thats good advise Paul. I for sure would rather stay under than go over.
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By Outlaw56 - 10 Years Ago
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Frank (or anyone having experience with AOD Lokar TV cable to Edelbrock Carb),
Would it be an advantage to come off the center port of the AOD and install a hose running towards the engine bay to mount a permanent pressure guage to monitor the transmission pressure when adjusting the shift tv cable?
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By charliemccraney - 10 Years Ago
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Here's a link to the chart Holley had when I got my 570.
http://www.northernperformance.ca/wp-content/uploads/2012/12/Holley-Street-Avenger-Carb-Selection-Guide.jpg
It indicates that it won't work with AOD and there are other caveats.
I think I need to correct something I said earlier about the Edelbrock. I said that the 600 worked fine on my warm 292 (+.060, B intake, C0AE heads, rams horns, 226 @ .050, .295 lift cam, 1.54 rockers) other than the air valve problem. I'm not 100% sure at this point, but I think the air valve problem did not occur until I had the bigger, better engine (stroker, ported heads, blue thunder, etc.). I've been thinking about it and I just can't remember that until after all of the upgrades. This suggests that the 600 should work fine on at least some 292s. Don't know about 272. A 292 is within 3% (is that negligible) of their 300ci recommendation and an overbore narrows that whereas a 272 is about 10% lower. So take that with a grain of salt, as they say.
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By Outlaw56 - 10 Years Ago
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From my research (no actual experience, just reading and gathering information), the 600 is over carbing a 272 that has been modified below 300. Personally, I think even a 500 is on the high side for 1 272 but I believe from what I have been told here it will work. Thanks for pointing out that the Holley Street Avenger will not work with the AOD Charlie. I have came across that several places. That was the reason for me asking what I had to be looking for regarding a carb that would or would not work with an AOD. There are several excellent videos on You Tube about installing Lokar TV shift cables with the Edelbrock Performer/Thunder series.
I will be installing my Edelbrock 500 Thunder on my stock 272/Manual. I will also remove it and try it on my 292/AOD once I get to that project. I think there is a good chance the 500 would be ok for both, but wont know until I have a chance to try it.
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By pegleg - 10 Years Ago
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Darell,
Sorry, don't get here everyday. Yes to the pressure gage. All Lokar says that I remember is to make sure the lever on the tranny moves as soon as the throttle begins to open. They supply you with very good instructions. If you don't have them I'd recommend going to their website and finding out which hole to use. Remember there were multiple versions of this tranny from trucks to Lincoln Mark VII's and Mustang GT's all of which used different levers and settings. Without knowing what your was I can't tell you much more.
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By Pete 55Tbird - 10 Years Ago
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Carburetor choice for a Y-block, or any other engine will depend on a number of things. What will you be using the car for and what do you want as far as driving experience? Is it a cruiser or is it a drag strip car? What transmission and rear axle? How heavy and what cam and or other modification have been done? To try to answer what carburetor is "best' is a question without a rational answer. Pete
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By hjh - 10 Years Ago
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Summit carb results
For my 2 cents worth on the Summit carb.I am using the 750 Vac secondary model on my 60 Merc which is 3800 lbs. + of car and driver which is going 12.60's at 110 MPH with the help of Mummert Heads and intake ported by Joe Craine.The car went 12.70 with the carb out of the box after I got traction and then broken axle problems taken care of. I am sure there made by Holley as it uses all Holley parts, jets, vac parts, power valves ect. The carb sold by Summit is a copy of the one Holley made years ago models 4010 & 4011 which was a copy of the AutoLlite carb but with some improvements.So the Summit carb gets my vote. They also offer that in 650 CFM also. Harry Hutten
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By Ted - 10 Years Ago
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Harry. Based on the results you were having at Columbus, I tested that same 750 cfm carb on a 303” Y with unported '113' heads and iron intake and was very pleased with the dyno results. 315HP and a very broad torque band. That engine is back in a ’56 Ford Victoria with highway gears and runs very well at all rpms with great driveability in stop and go traffic. The fuel mileage is also good even with ethanol laden fuels. It gets my vote also.
What helps to make that larger carb work well are the annular discharge boosters which allows for a reinforced vacuum signal thus compensating for the larger throttle bores. This carb ends up with good low rpm response and the cfm to accommodate some good rpms even on a smaller cubed engine. I’ve also run the smaller 600 cfm versions on engines but have no comparisons to its larger version on the same engine.
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By Dave V - 10 Years Ago
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Ted. I've been having trouble eliminating a hesitation off idle with a 600 Holley on my 312. Put a 390 Holley on it and it runs good now but without the performance that I would like. I was going to buy a 500 Edelbrock for something in between but from what i read the Summit 750 should work for me? Dave V
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By speedpro56 - 10 Years Ago
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Try jetting up two sizes on the primaries only, that works more often than not.
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By Dave V - 10 Years Ago
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Thanks for the reply Gary. Now I'm confused. Doesn't coming off idle have more to do with the accelerator pump and discharge nozzles? Dave V
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By Ted - 10 Years Ago
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Dave V (11/10/2014)
Thanks for the reply Gary. Now I'm confused. Doesn't coming off idle have more to do with the accelerator pump and discharge nozzles? Dave V Hesitation issues are typically a result of a lean condition which can be fixed from several different approaches. Gary is correct in that richening up the primary jetting can help with hesitation issues. A larger accelerator pump shooter and/or pump cam can also help. Reducing the idle feed air restriction holes is another option. Balancing the primary and secondary throttle blades so that the transition slot in the primary side is not overly exposed is also another fix. I’ve gone so far as to change out the fuel discharge nozzles to a different design on some carbs in which to increase the booster signal at low rpms.
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By charliemccraney - 10 Years Ago
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While I was playing with the accelerator pump on my 570, I noticed that some of the cams would not operate the pump arm immediately, I think in position 1. That can cause hesitation. Make sure the accelerator pump is operating correctly.
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By Dave V - 10 Years Ago
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Thanks for the replies and ideas. Hopefully I'll have a chance to try some before we get snow and salt on the roads. Thanks again. Dave V
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