Quite often guys ask questions about what carb works, So I thought I would share my experience.
Disclaimer : this are my own findings and based on a stock 292 , FORDOMATIC. With pertronix ignitor 3, timing at around 12 initial, total at 36-38 and all in by 2700 rpm. B manifold port matched, 1/2" 4 hole spacer for the carb. twin exhaust through Smithys. And bum dyno.

1. Started with a 600 Holley auto choke. Fine, worked ok . I think in the end I settled on 62 jets, 10 " P/valve,  blue pump cam , 31 squirter , black secondary spring  .  Good point seemed to always start no problems after sitting a few weeks. The 600 now sits on my 74 Cuda. changed settings of course, It works really well on that.

2. Went to a 450 Holley auto choke, supplied and rebuilt by Phil at RPM ind.  with that one I settled on 58 jets, 8.5 P/valve, green pump cam, 31 squirter, brown secondary spring. Good point.. None really was about the same as the 600, the only thing is that it seemed to dry out because of the vent in the float bowl.

3. Now on an Edelbrock 600 performer 1406 [the economy one with electric choke] was originally on my Cuda. With this one the stock needles and jets with the heavy 8" springs. I tried the next up rich needles [23] but it felt very much like the Holleys - fat. I have felt a difference with the Edelbrock it seems to have much better transition and though mid range to top end seems stronger, definitely noticeable with the standard needles. It did however have a very very slight of idle flat spot, I just moved the pump jet to the nearest hole and bingo all good, I found from a standing start I can floor it and it pulls away clean, slow as slug but clean, the Holleys Mmm just .  Good point, well I guess its the stronger mid range now thats important.. >>> [Also the kick down works better..??]

Because its a Fordomatic they can be a bit of a slug because of the way it works, as we know its really just a two speed. Start of in second gear and a lot of the corners - round-abouts etc your usually driving out in top gear..
 The one thing that has been evident with my car is that it likes a bit fuel straight up, note the "heavy pump cams"   even with the Edelbrock pump.
The Y block and Fordo - doesn't seem to be that fussy I really think that any carb from 390 to 600 CFM works ok, I haven't seen a revelation , just the stronger mid range in Edelbrock I guess.
Hope this helps someone..





"Came too close to dying to stop living now!"

2721955 Meteor. I think I understand what you saying , but just cant see it working as you have to manually put it in first gear ? I ve never heard of this  - anyone else? .. If you can find the article by all means put it up so we can see..

Dry Lakes.. The Holleys have been on for a few years each the Edelbrock is only just recent. Fuel economy; the Holleys were the same to me, don't ask me to quote mpg I'd have no idea. I think I would expect slightly better from the Edelbrock by going on the vacuum gauge, time will tell.
Yes, I would have thought the smaller Holley would have been best that's why I had it made up for me.. It is a 450  list 4548  - 0509. Not part of the off road - marine set, well as far as I know unless Phil changed the breathers etc .. I would have thought they might have centre hung bowls too..I don't know?  I'd like to try one of the 500 Eddies, but of course I don't have one under my bench ; )

Charlie what has the Avenger series got that the old ones don't?







"Came too close to dying to stop living now!"

To add to what Charlie has mentioned, the Holley Street Avenger series of carburetors are calibrated for more aggressive camshafts.  Because many of the ‘larger’ camshafts have a reduced carburetor signal at idle, the emulsion holes and air bleeds are sized differently to obtain the correct fuel mixture in the lower rpm ranges.  Many of the universal carbs have fixed emulsion and air bleed holes and are difficult to modify appropriately.  The Street Avenger carbs while still having fixed sizes, are sized for more aggressive camshafts and work better out of the box with modified engines.

Lorena, Texas (South of Waco)

Frank/Rebop

Bristol, In ( by Elkhart) 

HI Rob.
My Tbird will go to first of the line if I floor it, since I adjusted the kickdown.