kennycarpenter

I'm looking for better hp/throttle response while keeping the car as orignal as possible. Everyone tells me 750cfm holley with a thin adapter plate will help trememdously over the stock carter made q-jet i have now. Any other suggestions for this setup. Thanks


73 red coupe
A/T HEI conversion
completely stock

Jvette73

If you want to keep it as close to stock as possible take a look at the Q-jet replacement made by Holley. Spread bore design. I would choose the 650cfm model. 750 is ok on a high po motor. But mild build ups or stock should stay with the smaller carb.

1979toy

If you want a Holly, look at the Holly 570 cfm Street Avenger. This carb is set up for stock engines.
You might also look at the Demon. The Road Demon is rated at 625 cfm with vacuum secondaries.

Racer16k

I agree with Jvette73. The 650cfm Holley 4175 carb would work well. Summit has them at $299 part # HLY-0-80555C. They also have three different levels of performance Q-jets from $349 to $389. Stage 2 sounded pretty good at $359, well except for the price. I've had good luck in the past changing metering rods in Q-jets to improve performance. I remember a 78 Trans Am that I changed metering rods and dist. curve kit. That thing never would hook up the tires after that. Cool burn outs though!

SteveG75

If your car is all original, the Qjet was made by Rochester not Carter. That said, the Q-jet is a great carb when set up properly. I rejetted mine too rich, Lars helped me tweak it in Denver and it runs awesome now. I am probably pushing 275 hp with mods and got 19-20 mpg on the highway with awesome throttle response.

Lars email is lars.grimsrud@lmco.com . He runs a 12 sec GTO with a Qjet and I know of other cars that runs faster with them. Just needs a little TLC.

Tom73

No need to spend big bucks on a Holley. The Q-jet is just as good if not better for street application. Just get a good q-jet expert to give it a performance rebuild. That is all you need.

tom...

Ganey

Kenny

Properly set up Q-J works great for millions on street & track. If you want a Holley, 750 is too big for stock engine, get a 600.

:cool:

kennycarpenter

Steve, thanks for the info. From publications I did read that some q-jets were made by carter. My carb has no rochester wording on it, but does have q-jet and carter names f.y.i. I think they made a few that were put in production on vettes around those years.
K