The Z has been sittin for a while now, and lately i have had enough problemes with it to keep me busy every weekend for almost a month. First off ill describe the motor, its a 350 out of a 70's monte carlo big cam, stock heads, Quadrajet carb off original 82 305, dual plane intake off old 305, full length headders, no computer hookups, except for elec choke and nothing too specail about it. it was given to me by my girlfriends dad who was going to put it in his 69 Camaro but is going with a big block instead. Here's the problems:
1. Backfiring, tried timimg, module in Dist. and different carb
2. hard brakes, got a vac can to fix that and will be putting it in this weekend
3. sluggish when driving, feels like its gonna die but wont.

just today i had a small fire when it backfired through the carb!! I cant seem to figure this one out!! I ve tried almost everything and cant come up with any solutions. It drove fine last fall down to Ocean City MD and back, the only other thing i did to it was gut the cat cause it got clogged up. Wires on right, this ones got me bugged. Please help!!

 

how well/not well does it run when it runs? theres 2 things that come to my mind when i heard ur probs. and thats timing (which u said u did,but still sounds like it to me) and the cat might be clogged but u said its gutted. so im not sure what else to tell u.

 

well when its running its kinda rough untill it warms up, then driving it when u push the gas, its like it dosent want to go then it will eventually get the rpm's up after a couple of seconds. hard to describe, tomorrow ill check the timimg again but it was fine today, and its still backfiring.

 

how bad was the fire?

 

Not too bad, just a small one, scared the hell oout of me though!! I have a fire extinguisher handy at all times when working on any car, just in case. it shot through the carb burnt the hell out of the air filter, paper burns quick, and it put it out real quick. Pulled it outside and hosed the engine bay down cause the stuff is corrosive. Could this be a distributor prob.? i had trouble getting it in when i built the top end of the motor so mabey its a tooth off or something...I just dont know.

 

Definitly check your timing. If it still persists re-stab the distributor. When i first got my motor running it was hesitating, backfiring, felt very sluggish, etc and it turned out to be the timing and exhaust (at the time i was running shortys and the stock y pipe ) You also might think about changing carb. The quadrajet is good for a paper weight in my opinion. Try getting a 650 holley or edelbrock.

 

From what you're describing it sounds like the timing.

 

Check the float on the carb. My trans am used to do the same thing. The fuel fiter in the Q jet casing started to fall apart and it would mess with the float and the needle and cause the car to run realy rich and sluggish and when it was realy bad it would dump large amounts of raw gas into the engine causing it to back fire and catch fire.

 

Never run a computer controlled QJet carb without the computer hooked up. It defaults to full-rich and runs like crap. 82 Camaros only came with computer controlled QJets. Easily identifiable by the big blue 2-wire plug on the top.

Ditto a computer controlled distributor. If run without the computer hooked up it will give ZERO timing advance and, again, your motor will run like poo poo. If your distributor doesn't have a vacuum advance canister poking out the side it's computer controlled.

The combination fo the two will give you one really bad running motor.

 

-valves adjusted too tight
-timing out 180 degrees
-not getting enough fuel-check fuel filter for clogs or check if its flowing enough

 

I may have figued it out!! Im pulling ALL electronics and going with a completly different setup. No comp, new carb, 750 Holley, manual choke, mech. adv dist. and i hope that this works!! Got the carb for free today, was rebuilt 2 weeks ago never used, guy gave it to me for the quad ra crap. I got three more so it dosent matter. Well ill let yall know how it works out. thanks for the advice.

 

Mechanical advance distributor? If it's mechanical-only then it's not gonna have very good street manners. For a street car your really need a distributor with both mechanical AND vacuum advance. You'll lose idle quality and it may tend to backfire out the exhaust when you let off the throttle.

 

well thats what i ment to say. mechanical and vaccum advance, haha, thanks for catching that.

 

yep your timing is 180 out, the car will run but thats why it is firing out the carb, its because instead of the ignition fireing on the compression stroke its on the intake strock so the fire comes out the carb.

 

Ok i replaced the distributor with a mech. and vacc. advance dist, and ran a non elec q-jet, and was getting absolutely no spark!!! so i figured the dist is bad, i pulled it and replaced the module, pick-up coil, and the coil in cap type cap for it. checked plug wire routing, and all grounds, and still got no spark!! pulled that dist and replaced it with a re-built original on with the comp hookups, this time i got spark!!! and finally after three hours of adjustments, i got it to fire up!!!! ran like a champ, no more trying to make it turn over and half flooding the engine to get it to start!!! It took like two seconds for it start, it used to take like 10. My question is why was the dist w/o any comp hookups getting any spark?? does it have to do something with the comp? Phew long post, sorry, but this was hell of a long weekend. Any ideas on the dist prob? thanks.