Total timing ball park number for 292 Y Block?


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By Joe D - 5 Years Ago
OK Y guys, truck is running good but I think it can run even better.

Idle timing is set at 9 BTDC. I had retarded this from 19 when I had dual quads.

How would I check total timing and what would be a ball park number since all engines are a little different? Sounds like something you adjust and drive until you find the right sweet spot. I have been running 87 OCT. Manual calls for 4 BTDC for idle timing or base timing.

Thanks for your help,
By Florida_Phil - 5 Years Ago
You are probably going to get a lot of different answers on this one.  My 292 is running 9/1 compression with 1957 G heads, Holley 4V, a stock 1957 distributor with a Pertronics unit and a mild Isky cam.  I run 35-36 degrees total timing.  My motor idles more consistently without the vacuum advance line connected. I time my engine with a Craftsman dial type timing light.  I set the degree dial to 36 degrees and rev the motor.  When the TDC line stays on zero, I lock down the distributor. My motor idles like a watch on Florida pump high test fuel and pulls hard. I have a stock manual O/D transmission with 4.11 rear gears.  My engine never knocks or runs on.  Before you do anything, make sure the timing mark on your balancer hasn't moved.
By DryLakesRacer - 5 Years Ago
Phil, those timing lights are the best this that ever happened for guys setting total timing. Years ago tape or if you could get a 360* marked damper it was all a guess.
By Florida_Phil - 5 Years Ago
They are a YBlock "must have" in my opinion.  Most Y Blocks I have seen have only one timing mark at TDC.  Often it's just a rusty line and a pointer.  How anyone can time an engine this way is beyond me.  One of these dial type timing lights can tell you a lot about your engine.  I recently learned some things about the vacuum advance that I didn't know.  I never used the vacuum advance on any of my race cars.  I always timed my engines by total advance.  This Forum taught me what happens when you connect the vacuum line.  Very interesting and not at all what I thought.
By Joe D - 5 Years Ago
Ok guys I advanced the  idle timing to 14 degrees BTDC from 9. Total timing is 39 degrees BTDC. Truck ran better. More responsive acceleration.

Do these numbers seem reasonable for a stock engine 292 Y block, stock manifold edelbrock carb., headers, stock dual advance distributor with Pertronix electronic points?

If I advance more I guess at some point I will hear pinging (pre- ignition)?

Phil, I located TDC with a piston stop tool and made a new mark as the old mark was off.  Not sure what the old mark was. How can I tell if the balancer moved?
 
Thanks for your help,


By Talkwrench - 5 Years Ago
If you can load it up and hear no pinging youve got it.  Personally I think you may have to come back a degree or two, but I dont know what your fuel is like.   Its unusual that you can get figures like that  unless someone has already modified your dizzy, Thats close to my figures but I modified..? 
By Joe D - 5 Years Ago
Talkwrench,

Thanks, The distributor may have been modified by the previous owner who did the rebuild. I recently went to a stock manifold (single carb). It had dual Carter 4 bls. with vacuum secondaries on her and a Edlebrock manifold that I thought were causing the stalling issue. The issue wound up being that the valves needed adjusting. They were all tightened down (no valve lash). I guess someone didn't like the valve tapping!
The fuel in the Philly area is 10% ethanol and I just started using 87 OCT. I had been using 93 OCT but read on this site that my stock 292 Y doesn't need it.

I will experiment at some point and try the 93 oct fuel. 10% ethanol. I add Stable marine (green) at fill up. What type of fuel do you run? 

Thanks for your help,


By Talkwrench - 5 Years Ago
Joe , our fuel here in Western Australia is either 91, 95 ,98 octane but it measured different than U.S. 
We do have some that have ethanol , but its mainly eastern states.  I just run 91 thats for all my cars except the Cuda, the timing I setup for that cant really deal with the 91 so the lazy 98 it is!  
By Ted - 5 Years Ago
Joe D (3/21/2019)
...The fuel in the Philly area is 10% ethanol and I just started using 87 OCT. I had been using 93 OCT but read on this site that my stock 292 Y doesn't need it.

I will experiment at some point and try the 93 oct fuel. 10% ethanol. I add Stable marine (green) at fill up. What type of fuel do you run? 

Thanks for your help,

Unless you are doing an actual ethanol content check on the gasoline, you’ll not know for sure exactly what you are running.  I keep 91-93 octane gasoline in all my older carbureted cars as the premium grades in my area have no more than 5% ethanol and it sometimes checks out as low as 3%.  The reduced ethanol content does increase the shelf life of the gasoline and is also easier on carburetors, fuel pumps, and other related fuel system parts.  I no longer find any gasoline in a pump labeled ‘May contain up to 10% ethanol’ that is not ethanol free.  Adding ethanol to the premium grades seems to have taken place 8-9 years ago which is about the same time that it was mandated to increase the amount of ethanol being produced at a Federal level.  Before that time period, only the 87 & 89 octane grades had the mandated 10% ethanol.  I have had some sloppy running engines on the dyno and an ethanol content check of the gasoline being used has found as much as 30% ethanol in that fuel and that came from pumps that should have had no more than 10% max.  Going with a fuel with reduced ethanol content fixed those engines that had trouble with the higher than normal ethanol percentages.
By Florida_Phil - 5 Years Ago
Phil, I located TDC with a piston stop tool and made a new mark as the old mark was off.  Not sure what the old mark was. How can I tell if the balancer moved?
Without an accurate timing mark, you will never be sure of the timing.   If the old mark was off, your balancer may be compromised. You can time an engine with a vacuum gauge.   Before my rebuild, I did it this way.  Google it and see what you can find.
By DryLakesRacer - 5 Years Ago
My damper marks were off so I sent it to Damper Doctor and it's a one day service plus shipping time. I agree with Talkwrench about pinging, if you don't hear any, it starts easy, and idles nice 37-39 is fine.
On our 2 racing engines with great fuel, and 14-1 comp there was no gain over 37 so that's where We run both of them. One an inline and the other a bent 8.
By Tedster - 5 Years Ago
Like many people who replied, my anecdotal observations are pretty much aligned with what others have found. A stock Y will take a lot of advance and like it. At least, by '64 the Truck-only Y-block was considerably detuned with a low compression ratio.

On the plus side, this also means it will run tolerably well on mule-piss and corn-squeezins or low octane fuel. When you get it tuned well to take advantage of the timing, a bad tank of gas is immediately noticeable. Probably one of those 30 per cent batches of fuel that "accidentally" made into your local retailer. Now Etoh isn't "bad fuel" per se, but jetting, compression, and advance curves are different.

The key to tuning, and this took me a long time to figure out, is throw the vacuum advance away for a little while. Forget, for the moment, it even exists. Then as mentioned, make sure TDC is marked accurately, the damper is still damping, and find out what YOUR engine likes, with good fuel and the distributor innards are clean and tight and moving smoothly. 34°, 36° 38° maybe more, depending on altitude &c, ignition health. It takes some test drives, what you're doing is the poor man's Distributor Curving without a Sun tester. With Ford distributors it is Not Very Friendly to make internal adjustments, because the breaker plate must be removed. Ordinarily Lighter springs must be used, and check to see that the total mechanical advance is not excessive.

One question I haven't seen answered, Why do Dampers have a "0" Mark and numbers out to 40° BTDC , but also a -10° ATDC? Why would somebody time an engine to ATDC??? Maybe it was a smog thing on some engines? So why does my PowerBond damper have this mark? (Damn good dampers btw)
By oldcarmark - 5 Years Ago
Vacuum Advance Figure should be kept in mind IF You are leaving the Vacuum Advance hooked up. Don't forget at Cruising Speed when Engine Vacuum is High the Vacuum Advance will come back into Play. Depending on how much Advance is available You could easily end up with 50 Advance which is too much. Limiting the amount of Advance is a good Idea.
By Florida_Phil - 5 Years Ago
I recently had a chance to go through the distributor in my TBird.  I am running a stock 1957 single point distributor out of a 40,000 mile station wagon with a Pertronix unit and coil. It seemed to be working OK, but the idle was inconsistent.  Full advance didn't come in until about 4,500 rpm.  What I found was a bunch of dirt and gum around the centrifugal advance mechanism.  The ball bearings holding the advance plate were also dirty and hanging up. I didn't find any excessive wear.    I cleaned everything out with carb cleaner and soaked the bearing plate in solvent until it was totally free.  At the same time, I replaced the big spring in the centrifugal advance with a small spring.  I am now running two small springs and everything is free. My vacuum advance canister is new.

Before I took my distributor apart, I did not connect the vacuum advance line.  I always time the engine at 36 degrees full advance and lock it down.   When test driving the cleaned up working distributor, I found the car responded better with the vacuum advance line connected. It's a much smoother engine now.  I have an Isky cam in my motor.  It's not radical, but it thumps noticeably.  Now that everything is working, the car idles at 800 rpm and stays there.  Drive ability is much better.  When you floor it, it takes off like a rocket and revs to 5,500 rpm without drama.   Life is good.  Smile
By Tedster - 5 Years Ago
oldcarmark (4/6/2019)
Depending on how much Advance is available You could easily end up with 50 Advance which is too much. .




Too little advance isn't good either. 50° BTDC under certain specific conditions is very much typical for V8

In '64 the initial timing spec was 6° BTDC, but another 5° additional to that to improve performance or economy was acceptable.

Then the internal distributor mechanisms (reluctor, or slot) for 292 available were either 13° or 18° distributor degrees (e.g. 26° or 36° at the crank.) With a 13 slot there's 37° right there, at least at full throttle

The vacuum advance in '64 was rated at 6° and 1/2 (or 13°at the crank.) That's 50° right there.

Plenty of ignition advance under lightly loaded conditions is where fuel mileage can safely be improved, mostly at steady level highway cruise.

This is why vacuum advance was invented, there isn't nearly enough ignition timing advance available for best running at steady cruising speeds in high gear when using weights and springs alone, the engine will run too hot when the timing is retarded (and will run too hot when overly advanced, or too lean a fuel mixture)

It's worth taking the time to experiment a little bit and find a combination of initial timing, weights, springs, slot, tension, vac advance, etc etc that works for the particular application. It's important to keep in mind performance tuning is different than stock OEM tuning, or tuning for mileage or range.
By oldcarmark - 5 Years Ago
Florida_Phil (4/7/2019)
I recently had a chance to go through the distributor in my TBird.  I am running a stock 1957 single point distributor out of a 40,000 mile station wagon with a Pertronix unit and coil. It seemed to be working OK, but the idle was inconsistent.  Full advance didn't come in until about 4,500 rpm.  What I found was a bunch of dirt and gum around the centrifugal advance mechanism.  The ball bearings holding the advance plate were also dirty and hanging up. I didn't find any excessive wear.    I cleaned everything out with carb cleaner and soaked the bearing plate in solvent until it was totally free.  At the same time, I replaced the big spring in the centrifugal advance with a small spring.  I am now running two small springs and everything is free. My vacuum advance canister is new.

Before I took my distributor apart, I did not connect the vacuum advance line.  I always time the engine at 36 degrees full advance and lock it down.   When test driving the cleaned up working distributor, I found the car responded better with the vacuum advance line connected. It's a much smoother engine now.  I have an Isky cam in my motor.  It's not radical, but it thumps noticeably.  Now that everything is working, the car idles at 800 rpm and stays there.  Drive ability is much better.  When you floor it, it takes off like a rocket and revs to 5,500 rpm without drama.   Life is good.  Smile


I have that same Type Distributor in mine. The '57 with the Ball Bearing Breaker Plate. I lucked out and found a NOS Breaker Plate on Ebay. The One in Mine had developed Flat Spots in the Balls from moving only a small amount over the Years. One other Adjustment I made was to ad a couple of Shims between the Collar and Body to get the Vertical Play within Specs. There is a preferred Spec for that Measurement in the Shop Manual. .022-.030. You mentioned You changed the Heavy Spring to lighter Spring. You can also adjust Centrifugal Advance by working through the Small Hole in Breaker Plate to bend the Posts that the Springs hook onto.That can also be done on the later 2 Piece Breaker Plates. Ford had a Tool for that but I think One could be improvised. You can fine tune the Advance if You are so inclined. Too bad the old Sun Machines are gone.You could really Tune a Distributor on One of those. Where did they all go to when they were taken out of Service.? There was a mention in one of the other Posts regarding a lack of Timing Marks after about 10 BTDC. Mr. Gasket sells a Timing Tape #1594  for Small Block Ford that is pretty Accurate when used on a Y Block. Off a little bit because of the Difference in Diameter but can still give a better Idea of Timing than not having Marks at all past 10 BTDC. .
By Florida_Phil - 5 Years Ago
I called all around trying to find someone with a distributor machine in my area.  No luck.  It seems they all went to the big engine shop in the sky.  I found the same thing looking for a wheel balance machine that could spin balance my wheels and tires on the car.  The new computerized wheel balancers aren't worth a damn. 
By famdoc3 - 5 Years Ago
I don't know where "all those Sun machines went?" ,but I do know where went....my basement! It sits comfortably there and is a cool toy to have. MIKE
By oldcarmark - 5 Years Ago
Florida_Phil (4/7/2019)
I called all around trying to find someone with a distributor machine in my area.  No luck.  It seems they all went to the big engine shop in the sky.  I found the same thing looking for a wheel balance machine that could spin balance my wheels and tires on the car.  The new computerized wheel balancers aren't worth a damn. 

I guess they are a Collectors Item now. I remember We had One in Auto Shop in High School. Wish I had learned a little more about it then. Nice to have it now.
By Florida_Phil - 5 Years Ago
Here's a funny story.  Back in the sixties a friend and I went to a local speed shop.  They had some guy there talking about distributor curves.  My friend was a wise guy with a very sarcastic humor.  He also had one of the fastest cars at our local drag strip.  The man giving the talk said "For $10 I can give anyone in this room a 10th on the drag strip!"   My buddy said in a loud voice "I'll take $100s worth!"   I still laugh about that.
By Rono - 5 Years Ago
Phil;
What RPM are you at when your timing is all in?