I have a 1986 trans am, it has a stock 305 carb engine with a q jet and stock cold air intake through a vent in the hood. I am having a 406ci small block full roller engine built looking to get 400+ hp. My mechanic said I can't use a stock intake and the q jet carb. He said the carb is built for gas millage and emissions so its a no go. I would like to keep the stock air filter base if possible any ideas? One thing I DO NOT want to do is cut a hole in my hood. If I can't go with the stock air filter what can I do as far as intake manifold carb air filter set up that won't require me cutting a hole in my hood? Also I was wonder about my rear its a disc 2.73. I read some of the rears took regular oil from factories while one other took synthetic also pinion size would mine be an 8.5? Thanks!

 

A stock Qjet has no trouble supporting 400+ HP when tuned.

 

Regular oil (with additive if it's limited slip). Ring gear would be 7.5" (or 7-5/8").

Assume you have the early TA with the fresh air inlet through the hood into the cleaner? The q-jet will be fine. The stock manifold may be slightly restrictive but do-able, equivalent to an edelbrock performer.

 

Thanks guys I may have a hard time convincing my mechanic of that, he has been building small blocks for better than 30 years and is pretty set on his holleys, he hates edelbrock carbs too. Part of the problem is that I have a Computer Controlled q jet and it definitely needs to be rebuilt. This is a strange carb and it very few mechanics are willing to touch it. One described the process for tuning it to me, it sounded like a pain in the butt he said he had all the special tools and info needed but told me I was better of buying a new carb than trying to rebuild and tune it. So I would almost have to buy a new or rebuild q jet. What would be a good intake that would sit low and would work with a q jet and support a cam with an rpm range of 2800 to 6200?

 

Find a better mechanic.

 

Performer RPM, spreadbore but you may have some clearance issues as it sits a bit higher.

If you want to try to rebuild it yourself we can help:

https://www.thirdgen.org/forums/carb...-ccc-qjet.html

If you swap to a different carb you'll also need to swap the distributor because it and the carb are computer controlled. If you have an auto you'll need an alternate method of controlling converter lockup. If you've got a manual trans a mech secondary carb will have a slight advantage over the qjet.

I'd use as much of what you have as you can, then decide later whether you want to swap anything out.

 

I hadn't realized the distributer was computer controlled too its an hei not like the distributer on a tpi motor. The trans is a 700r4 doesn't the detent cable control lock up? My mechanic said he could rebuild it and would but he hates q jets he said 750 holley or nothing. I know he knows how to build an engine he has a 72 Oldsmobile a big old boat its tubbed and the and lightened up but its still a big car he has a picture of it on his wall doing a wheelie with a time slip that says it ran a 1/4 mile in 9.5 seconds the car has a punched out 327 in it now a 331. I asked him how he could get it to lift its front tires off the ground like that and he told me he spent $10,000 in parts on the motor back in 1976. He said you rev the engine up to 10,000 rpm and sidestep the clutch then you just star shifting as fast as you can! The car and engine are the originals from 1976 it still runs great and has never been rebuilt. He also has a an 68 el camino he bought back in 1974 he just finished redoing from the frame up he did all the work himself, all dents and dings he leaded like they did back in the day instead of using body putty. The car is amazing he built a 454 for it that has over 600 hp. I don't need a new mechanic he just rebuilt my friends B16 engine in his 2000 si honda. I just need advice on what I can fit under my hood. Even if I stick with a q jet I still think I will need an intake that will flow better, I had an rpm performer on a camaro I had and really liked it, I had a 650 holley with it and had to cut the hood it looked good on the 84 camaro but I don't think it would look good on my T/A. That setup was really nice though it kept pulling all the way up to 8200 rpm though I used to shift at 7800. This motor though being a 406 I just want to rev up to about 6500. Thanks guys sorry about the long post but I must defend my mechanic!

 

TPI distributors are HEI.

700R4's don't have a detent cable, they have a throttle valve cable.It doesn't have a thing to do with lock-up.

 

Huh I don't remember my Tpi distributer having a coil on top but I havn't had that car for years so I could be mistaking it with another car. I live in maryland and have the car tagged historic so I don't need to go through emissions. I just talked to my mechanic and he said he planned on putting a switch on the converter so I don't need the computer for lock up and he said we would switch out the distributer to an hei that doesn't have the extra pigtail for the computer control.

 

It's called HEI because it's electronic, not because of where the coil is.

 

You'll note that the stock HEI on your car does not have a vacuum advance can on the side. The computer controls all of the timing.

A mechanical dist can be had for around $100. You can install a lockup kit (or wire it yourself with parts) for a little less.

The holley (at least the one I suspect you'll want) won't mount to your current intake without an adapter, which would add height. Best to measure your clearance now and compare it to the height of the parts you want to install. Placing a low clearance, drop base air cleaner to clear the hood could negate the improved airflow of the rest of the components beneath it.

 

Later (87 up) HEIs used a small cap and divorced coil. Earlier ones had the coil in cap and were either computer controlled (no vacuum can) or mechanical.

 

I like the idea of the rpm performer do you think a holley 750 with an offset airfilter would fit under the hood? Has anybody tried this? Has anybody tried to put the oem air filter on a holley? It sits down over the carb instead of sitting on top of it I'm sure that I have room for a bit taller intake with a q jet and the stock air filter. But the guy that is building the engine while he says a q jet will work really thinks I would get better performance with a holley.

 

Placing a low clearance, drop base air cleaner to clear the hood could negate the improved airflow of the rest of the components beneath it.[/quote]

So its a catch 22 I spend money get better airflow and than negate it with the airfilter darn! Anbody have pics of a T/A with a cowl induction or other hood? maybe I'll see something I like.