Our Community is 940,000 Strong. Join Us.


Olds 403 engine troubles


boysatt
04-19-2006, 03:59 PM
I am new to olds engines. I am a chevy guy but i got this 1979 trans Am last fall that had a 403 in it. The car needed some tinkering and the previous owner didn't have much time to fix it. but I got it running, it has a 403 with under 2k on the rebuild, pumched .20 over, high performance cam, edelbrock performer intake, mild porting on the heads and intake, had new rods and lifter installed, and the usualy new stuff, and I also have headers on it. I am runnning a remanufactured stock q-jet carb, bevlieve its like a 800-850 cfm carb.

Well I started working on the car this spring since I wanted to drive it and I can't get the engine to run right. It runs alright, but not smooth, engine shakes a little and enhaust sounds like a drag car. I checked the timing and its set I think at over 12 advanced, ( I think that is what it is, but the mark is showing before the gauge on the timing cover, and when I try to turn the distributor to get it to 0 the engine starts to run rougher and rougher until it will die at about 6. So I am not sure what is going on there.

I got the timing set the best I can to make the engine run as sooth as I can and judging from the timing gauge, its at like + 14 or 16, wich I think is way too far.

Now I know this engine should be making some power, but when I step on it, there isn't much there, its like its only running on 2 barrels on the carb, accelerates slow. Then the engine tops off at around 4K rpm, then is will start to sputter, won't rev past that.

Any ideas? I know this engine stock has some torque because I have had a stock 403 trans am a few years ago and it could burn the tires off all day long.

Mike

Madcat455
04-19-2006, 07:33 PM
Oldmobiles (like Buicks) LOVE ADVANCE!!!!... Set it at 20deg. initial, then hook up the vacum advance.

I had an Olds 350... first V8 car I ever had (dropped it in a 81 cutlass). Since I was trained on Chevy's, I set it at 8 deg. Damn thing never made any power, would run like crap. Wouldn't even brake torque the tires.

Then a buddy's Dad (who was a GM Mechanic)... heard of what I did and smacked me (literally..lol). He said to do the same thing I just told you. Did that 350 ever WAKE UP... went from not being able to brake Torque the tires, to laying down rubber till I'd had enough.

Your carb is probably only a 750. As far as I know, only the Buick 455's came stock with the 800 Qjet (and that was only on a couple of years). I could be wrong, but I'm pretty sure they didn't get over 800 at all. If you get me the Numbers off of it (by the throttle linkage), I can look it up and see exactly what it is.


Get the timing straight, then go tuning from there.

Good Luck

Add your comment to this topic!