Do i need a tune?

[Chrismikeb]

i recently bought a 93 z28, has llp headers and y pipe, slp cat back, no cat...when im decelerating the exhaust sometimes pops randomly until 2k rpms...and it also idles right at 1k is this right? the guy told me that the passenger header leaks exhaust and to change the gasket. come to find out the freakin back bolt hole dont line up a so theres not a bolt back there. ill have to unbolt the hole thing and see if i can get it to line up...is this why its popping sometimes and idling high? or does it need to be tuned also? i dont know if he had it done or not, id appreciate the help..

[NoShow]

High idle and popping are lean fuel condition. I don't know what fuel injectors are available for that engine, but if you got some that were 3 or 4# higher flow than the current ones it would probly do it without getting a tune. Either way you need bigger injectors..

I don;t remember if that 93 is OBD1 or 2? I know you have a 4l60 (non-e)

[shtnfrds]

its just an exhaust leak. un bolt the header and line it up, wight as well use some red rtv to get a good lasting seal. do that and i bet it doesnt randomly pop anymore.

why would he need bigger injectors?? there is no mention of a cam or anything that would require larger injectors.

and everything needs a tune, it how MUCH of a tune does it need is the question.

[Chrismikeb]

i got the t-56 i dont do autos...but ya ima line up the header see if that fixs it...any idea what a tune would cost me? should just be a/f ratio adjusting right?

[tdevil55]

I own a 93 as well, and I got popping when I let the engine rev down from higher speeds. I put a cutout on mine after the cat, and it didn't pop on deceleration till the cutout was there. You may be getting the popping in the exhaust from the deceleration with the aftermarket on it cause of the less restriction. Another thing to take in consideration is that the 93 was speed density, so there is no MAF, so the air/fuel may need to be adjusted. The idle may be a little high, I think mine idles around 1k when I first start it, but drops some, maybe 700-800 when its warmed up. Mine is running rich, but I am willing to bet the owners before set it up that way, and it was tuned to run rich. They also upgraded the fuel pump, so that may be causing the richness in mine also.

Line them headers up, seal them good, that will keep future issues from arising. I would say a tune wouldn't hurt, but I'd get it done where they know what they are doing. Another route is the mail in tune. It's cheaper, and I think they talk to you about your setup and what you want the car to do. I haven't done it myself, but looking into it later this winter to adjust mine. Someone else may have done the mail in tune, and will give us an opinion on it.

Originally Posted by NoShow

I don;t remember if that 93 is OBD1 or 2?

It should be OBD1, I think between 94 and 95 was when they switched to OBD2.

[ND2RACE]

Originally Posted by Chrismikeb

i got the t-56 i dont do autos...but ya ima line up the header see if that fixs it...any idea what a tune would cost me? should just be a/f ratio adjusting right?

To be perfectly honest with you a 93 f-body is a hard car to get tuned. Being OBD1 and a change over year causes issues. I have a friend with a 93 Camaro and it was hard finding someone with the tools to tune it. Hopefully you can find someone near you with the know how and a chip burner. There is always the option of a mail order tune also. Best of luck to you.

[Chrismikeb]

appreciate the advice