93 lt1 m6. Fighting cam surge I think

Discuss General Motors (GMC, Chevy, Pontiac, Hummer, Cadillac, etc) tuning topics here. Request definitions, discuss parameters, etc.

Moderators: robertisaar, dex

Post Reply
Grabbem88
Posts: 1
Joined: Tue Dec 15, 2020 1:51 pm

93 lt1 m6. Fighting cam surge I think

Post by Grabbem88 »

Figured I’d sign up and get some knowledge

The car: 93z28m6 355 dart 180 le2/3 2.08/1.60 56.5cc
.622/.637 231/241@112+5 hooker headers Borla 30lb inj.
Ported intake 2800miles.
Did the Mail order thing with pcmforless and Solomon
Solomon first tune netted me 365/357 10.8-11.2 AFR

Problem 3rd at 22-2400 40mph I get this surge/miss wideband shows 13-15.7 back and forth when this happens
4th 18-2000 at 40-45mph same thing. 1-2 no issue 5th-6th ok until I reach 2500 at 85-90 below I can cruise.

I’ve added fuel up to 10% in area I saw on log ve table 30kpa-55 I’ve taken away added timing took away

Played around with enrichment vs tps o2 swing but I only took mv up not down. So I put car in open loop and car runs a lot better don’t even notice the surge

Then I was given injector offsets thinking mine were wrong
Ran with no surge but very rich 9.0-11 then warmed up 12’s instead of doing a complete retune I took injector value of 30 to 34 lol nope same crap then 31.5 nope again back to 30lb ran okish. So my end result. Put original decent tune in but raised coolant vs open loop to 110c (open loop) and called it a day.
No codes replaced and replaced sensors O2’s double checked tps iac oh stock 48mm with airfoil btw
Vac was 12-14
No leaks no smoke. Just this annoying surge at those rpms
Wot in 3rd is 12.9 4th was 12.4-12.6..
Not sure what I need to look at or missing. Very new at tuning but I’m trying. Have files and logs at the hip
Thanks Art
Post Reply