So last year I bought a 1987 trans am originally with a 305 ccc. The engine was toast, I swapped in a long block tpi 350 from a 1991 3rd gen iroc. Buttoned up all the stuff missing, new ignition and distributor, and it starts well but drives rough, lots of fuel smell. Plugs were black instantly. I was quoted 420.00 to rebuild the quadrajet (with new solenoids). My issue is, I eventually would like it to be a 5 or 6 speed, and a bit more wild than mild small block. Prolly a decent cam, after market heads, performer intake. Right now it has shorty headers and a open air cleaner. Do I waste the 420 for a year or two of driving or just get a good 650 cfm that will work for both applications. I heard quads don't like alot of performance, I know they are good carbs, but the rebuild is over half the price of a decent holley and I'd rather go that route. My cars an auto now, but was told the 1987 700r4 can be converted to the old style lock up or get a switch for it for now. I appreciate any and all advice and so on. I haven't looked into the build that I wanna do, but I'd like a bit of a decent upgrade in power. It will be for a weekend cruiser not that it really matters. Thank you

 

It's a weekend cruiser. Have the quadrajet rebuilt, drive it, and enjoy it for what it is: a cool piece of 1980s history.

Your story sounds like the millions of identical stories out there. Boy finds cool old Camaro, buys cool old Camaro. Boy wants to make cool old Camaro faster and cooler by "modding" it and making it "faster". Boy ruins cool old Camaro by swapping on parts he knows nothing about. Car sits in yard waiting for those parts to work or to afford the other parts/transmission/engine that he wants. 20 years later and 3 more owners the car is dragged to the scrap yard and crushed.

Spend a few hundred on a carb that will have it running and driving. These days $420 is cheap. If that sounds expensive to you then you definitely cannot afford the improvements of which you dream. Drive it now and ENJOY IT.

 

My used motor was 450 bucks, I'm not worried about price. Just seeing from experience what worked for both options things I plan to do. I bought a clean 87 to give to my daughter some day. Not for collectors sake, I bought to make my own. I will be converting to manual(likely a 6spd out of a 4th gen) and will be building a small block as specified. I don't want to put money into the ccc if it will give me more headaches when I build it. Looking for advice on my topic not what I should do with the car. Appreciate the input!

 

And I get it, no one wants to do it the right way. I didn't plan on cutting anything out but removing the computer and harness for in case I'd ever want to put it back on. Not desparaging the quad, they are good carbs from what I read. But this isn't a boy with a pipe dream, I bought it, replaced the motor and necessary things. And in hindsight I may of jumped in. I have no issue getting the quad setup for the 350 but if it's going to be another 420 or more next yr to set it up IF it will work with a more than milder built 350. If I have to learn a carb to setup, I'd rather do it with a holley and a/f gauge and vacuum gauge. I understand if it was a GTA tpi or something rarer but this is my car and I want to see what opinions may work best for me and my applications.

 

So is the long block good? Swapping a tpi over to a carb will require a new intake/distributer and fuel system or switch for the pump. Currently the pump is turned on by a relay controlled by the ecm. The fuel pump puts out pressure for efi so you'll need to get it down to carb pressure. I think your speedo is connected to the ecm as well(?)

if the tpi is running rich it may be something simple. you swapped the entire 350 injectors/harness/ecm? It may make more sense to figure this out instead of swapping to a carb and then swapping to a different carb again down the road.

heads up, these cars don't have a bunch of hood clearance. Be careful w you're intake/carb/air filter choices!

 

I just put the long block in, so the car is still carb controlled by ecm. The long block accepted everything from my original engine, and aside from a few things(spark controller, prom chip, knock sensor, upgraded ecm) and runs pretty good, only thing is it is flooding with fuel and the quadrajet needs a rebuild. Was the same issue on the old motor, everything was soot black.

 

The only thing tpi is the long block, my car is one of the few carb'd 305 made in 1987 US.

 

The Rochester Quadrajunk in action.


10.58 @ 123.70 MPH

The impact you see at 30 seconds into the video is the front tires crashing back down to the ground after it packed the wheels on launch. The engine is turning right at 7,000 RPM at the top of the run.

The Q-jet carb is whatever you want it to be. Grannie's 1979 Caprice wagon she only drives to the store, visits to see the grandkids, and to Church or a full blown race carb like this one is.

The normal Q-jet and the CCC Q-jet are the same on the secondary side. The secondary side means business. The primary side is for excellent throttle response and gas sipping fuel economy. Only the primary side is computer controlled. On cold start the mixture control solenoids go full rich, then goes into open loop mode, then when warm enough and seeing an active O2 sensor it goes into closed loop mode adjusting the mixture control solenoids trying to keep the AFR at 14.7 to 1. At WOT the mixture control solenoids go full rich on the primary side and the secondary side does whatever it's mechanically programmed to do.

 

I also forgot to tell you something last year when I was helping you out.

With your headers you are also going to need a 4 wire heated O2 sensor because of the heat loss compared to the cast iron manifolds. The O2 sensor needs to be about 660F to give out accurate data to the ECM so it can make the adjustments needed.

I'll add a link in a few minutes. I'm going to the store for RC colas and smokes.

Casper's Electronics 103025 | Heated Oxygen Sensor Retrofit Kits | Summit Racing

Heated 4-wire O2 Sensor Retrofit Kit for Early 1 Wire GM O2 Sensor

 

87 LG4 would have used a mechanical fuel pump and the helper pump in the tank. Still using both of those? Is the mechanical pump a GM pump or an aftermarket? I went through 2 aftermarket pumps(Carter) that were putting out way too much fuel pressure before I put a NOS GM pump on that solved my issue. Not saying that's your issue, but it's something I had to deal with.

fwiw, I used Mountain Man Fuel Systems in Arkansas for my CCC rebuild and he did a great job. I think it was around $300 with shipping. I would start there, get the car running and driving and then start compiling your parts for future performance upgrades. I wouldn't expect it to be a plug and play fix though. Most likely still going to need some tuning with a dwell meter to get it dialed in just right.

 

Airwolfe! I completely forgot to wire up the heating element to it, as if having an infant wasn't enough we have had great tragedy in my wife's family just before Christmas and that has side tracked a lot of progress. I forgot some stuff, I think I will contact mountain man and see what they say. I have no issue keeping the quadrajet in it, I know they're are good and I'll learn it if I plan to stick with it. I heard they didn't like big cams, and I ultimately want this to be a fun good power manual car.

 

spend $20 on a rebuild kit and try it yourself. if it don't work go another way

the ccc-qjet is great when all is working properly,,, but with the age of the parts/pieces for the entire system (dist/sensors/wiring/ecm) it's hard to advocate keeping it any more.

I'd also hesitate to recommend a replacement carb when an aftermarket, bolt on EFI system is available and inexpensive.

 

I looked into a few rebuild instructions and forums, bought a rebuild kit last year at the parts store and I agree, I think I'll dig into it when I get some free time this weekend. Also not opposed to a efi setup just didn't want more work to cruise it this year. It would really only be driven in summer months, so I figured a carb wouldn't be too bad. I very much appreciate all the info and input! Very excited to get it driving. Also airwolfe I did end up putting a heated O2 in just didn't hook it to power source and ground yet.

 

Mountain man said that fuel injected motors don't like carbs unless you swap the cam. I'm sure there is truth to that, but it drove about 3 miles and it wasn't horrible. I'll be buttoning up a few things in the coming weeks and I'll chime back in then.