I have an 87 gta 350 and it ran great but i put hooker 2055, high flow cat already had the cat back opened the air box some and advanced the timing alittle, but its running rough now would the headers throw off the computer enough to need a tune, I dont know how to tune on my own but theirs a dyno and the guy there tunes and its about 5 minutes from my house or should i look for other possible problems

 

it shouldnt. how did you adjust the timeing. did you unplug the spark advance? what do you mean by rough? does it idel rough or is it when your on the the throdle?

 

I think i might have a leaking injector it doesnt want to run unless I am really on when I first start after its been sitting for a while it idles irractally then it levels back out around 800 rpms like it did before did do the advancement my friend is a mechanic and told me that after it was opened up some that it need to be advanced some

 

hhuum. is it showing any codes(check engine)

do you know what he advanced it to? if not do you have a way to check it your self?

 

not showing any codes dont know where its advanced to if u tell me where it should he will put it there so any help is appericated thanks pz

 

If you haven't already, I recommend you pick up a Haynes manual. They are cheap and will have all the basics. If you have TPI, you must disconnect the usually tan lead by the blower box to eliminate the computer advance. This will throw up a trouble code, so don't go nuts if you get a spark control code. Most V8 motors are usually 6*, so I would start there. Also, stupid question, but did you hook up the AIR tubing? If you look around, they are also a host of little tricks like eliminating the coolant flow through the throttle body, as well as cold air intake kits. If you want to really go nuts, you can tune your own chips, but it's a little bit of an investment. Check out moates.net for the stuff. You will need a good laptop that won't freeze up from the slightest shock. P.S. GO STEELERS!!!!!!!!!!!!

 

I had a similar problem with a rough idle in mine, it's TPI, I pulled the chip and let it run on MEMCAL only, and the idle straightened out. I'll let you know when I finish the PROM work, if it changed things.

 

I went from a 305 to a 350 and added all this stuff

Edelbrock hi flow tpi
ZZ4 camshaft
SLP 1 3/4 headers
3" catback
I had the 305 prom in it and it ran like a champ