79' TA - Carb tuning for better performance

[jvmagic]

Hi,

I had my carb rebuilt (Cliff rebuild kit) and my 79' Trans Am runs smooth and all but I'm thinking in 79' they really choked these things.  Are there any tricks to make these q-jets perform a bit better?

79' TA
403 Olds motor (all original)

Thanks in advance.

[Cliff Ruggles]

The "choke" is probably more in the engine than with the carb.  The 17059253's are excellent, 73 main jets and CV secondary rods.   They don't need a lot of help anyplace when used on the stock 403 engine.

A good free flowing exhaust system would be a good place to start, nothing smaller than 2.5" mandrel bent pipes and preferably an "X" or "H" pipe ahead of the mufflers.

Higher compression and better cam would certainly wake things up as well, those engines have pretty low compression and the cam is pretty mild and probably retarded for emissions.......Cliff

[jvmagic]

The "choke" is probably more in the engine than with the carb.  The 17059253's are excellent, 73 main jets and CV secondary rods.   They don't need a lot of help anyplace when used on the stock 403 engine.

A good free flowing exhaust system would be a good place to start, nothing smaller than 2.5" mandrel bent pipes and preferably an "X" or "H" pipe ahead of the mufflers.

Higher compression and better cam would certainly wake things up as well, those engines have pretty low compression and the cam is pretty mild and probably retarded for emissions.......Cliff

Thanks for your input!  I'll look and see what CA emissions allows me to modify.

[BanditRich]

True dual exhaust would definitely help and as long as you have 2 CARB (California Air Resource Board) compliant catalytic converters it is legal in Cali. Also switching rear end gears from the typical 2.56 to 3:23 or better yet 3:73 would definitely give your TA a wakeup call. Anything higher than 3:73 would have the RPMs too high and your car will sound like a buzz saw on the highway and not be enjoyable.
I had a friend with a 79 TA with a 403. It was highly modded with a cam dual exhaust etc. My TA is a 78 with the W72 400 done up same as his and he asked me why mine was faster than his so I told him he had to change the rear gears on his (mine has 3:23). I told him not to go higher than 3:73 but he didn't listen - he had his mind set on 4:11 ( I think the garage guy talked him into it - most likely it was going to require more work & be a bigger bill and more profit for them). Well the first time he took it on the highway he found out I was right. He did not like how high the RPMs were at highway speed.