Would altering the exhaust system on a SD TPI l98 effect performancc/ mess up computer calculations of a/f ratio? since SD relies on the speed of air, and the density of it, wouldnt an exhaust system that flowed better mess it up? I did a search and read something that indicated this on

https://www.thirdgen.org/techbb2/sho...raight+%2Bpipe

is there any validity in this? im contemplating putting a straight pipe set up on a no cat(straight piped cats) g92 l98 92z28 that currently has a cracked SLP cat back, and wondered what benifits and drawbacks I may incur

 

I have full exhaust and it didn't mess with the computer. i could probally get a little more hp with a custom chip but it runs fine so im not messing with the chip that much till i get my heads and cam. sometimes people get check engine lights when they put headers on but i didn't but with. With a straight pipe I think you would probally lose some torque but gain horse power. My friends with mustangs put off road h pipes (no cats) on their cars and they lost some low end torque

 

In my '90 L98 corvette (SD), I noticed no sotp loss of low end torque with my Hooker headers. I have the Hooker Y-pipe w/o pre-cats....the exhaust was left in the factory Y-configuration. I definitely noticed sopt power gain throughout the rpm band, it revved a little better and a little higher. No changes were necessary to the ECM chip to account for this exhaust mod.

As the previous post mentioned, when you move to heads/cam upgrades - and intake upgrades - thus making major air input changes - then making corresponding fuel adjustments (custom chip) is absolutely mandatory in a SD car......probably not so with MAF.

 

hmm i see thanks, i currently don't have cats.. just gotta think about what the outcome w/ no muffler would get..

 

I'm thinking loud

 

Speed Density uses manifold pressure (vaccum) and rpm's for it's calculations not the speed of the air, that is Mass Air Flow. If the old system flowed well enough to handle all the power needs of the eng then you will prolly won't need to adj the computer but if it unleashes some power then you will, of course if that was true there would no need to change exh system unless you where going to upgrade the eng.