Been doing some mods (see sig) to my 2K LS1 Z28 A4 w/SS hood seems to be running a little stronger now but not what I expected. I am experiencing a lag at around 2500 rpm that I cant figure out. Did a search but didn't come up with much.
I am thinking it may need a tune but I have a Vettedoctors custom cam from my freinds C5 that I want to install along with replacing the injectors w/ 30lbs, lid with a Fast Toys and the MAF with an LS6 85mm before getting a dyno tune.

The check engine light is on and the only code is pertaining to the EGR removal. Other than this lag @ 2500 the car runs & idles great. Thinking of installing a new fuel filter but I dont think that will cure it.

Any thoughts?

 

No need to de-screen your MAF with your mods. Try a stock MAF and see if it is still there. Also, EGR allows you to run more part throttle timing. You may be getting spark knock because you had it removed.

-Geoff

 

Mine's been doing this too, lately. Only seems to do it at around mid-throttle and usually right around 2500-3000 rpm. Almost like a hesitation or bog. Usually lasts for less than a second, but it's been getting annoying. Full throttle pulls normally.

 

I rectified this problem by installing the FTP lid & 85mm MAF the 2500rpm lag is now gone. The LS1 pulls hard all the way through the rpm's like it should
I think my lag was caused by the egr removal because I ripped out all the egr tubing right to the elec pump but i kept the air lid tube connected which I believe was causing an air leak in the intake. Can't really confirm this but my car is running awesome now even though it has not been tuned yet.

Went to E Town last Friday & ran 13.60 @ 105 2.1 60ft street tires, not bad for a 177K mile LS1.
This weekend I am ordering the strange 2 series 342 gears GOT to ditch these 273's
After that I am sliding in the hand me down cam from my freinds vette then a dyno tune. I am hoping for 12's after these next mods.

I would check your air lid / intake area real good for leaks, good luck hope you can fix yours.