When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
So, I am OLSD tuned on this car for some time. never really had it dialed in and finally getting around to putting the combo to the test.
It is a gen III, L33, ls1 0411 ecm, SD 80#, twin in tank pumps, 58lb base pressure, boost referenced. All this in a 6 speed 69 nova.
What is happening is a few things:
There is a stutter at about 4K rpm that you can almost see in the RPM curve. What it does correlate to is the injector pulse jumps up and not sure why.
When I run the car at 43# base fuel pressure, I do not see the issue as much but I am going to want the higher base pressure since I will be going to E85 soon and do not want to jump to bigger injectors to make my power goals.
For the injector data, I have seen there are at least 3 different sets of injector data out there so I have the one loaded up that seems to work best.
Any idea as to what it could be and any thoughts on how the log looks?
thank you
Last edited by Chicago TDP; Aug 21, 2018 at 10:24 AM.
Reason: add pic
Your SFR from the PLX says 10.4 or so at wot. A little rich. You are asking for 11.2, so I would guess that you need to adjust your VE table. Are the spark plugs gapped around .025? I just looked at the scan and not the tune.
Yea, the VE is choppy on this last tune. I had just adjusted the base fuel pressure and few other items in an effort to try and correct the stumble/stutter. I battled a voltage issue at my pump(s) so when I got the wiring right, the pumps kicked up the PSI by another 5 or so PSI. The prior VE was nice and smooth. as of now, I have not found a correlation to the stutter and a choppy VE.
Did just pick up some new plugs at lunch today, will throw them in the car tonight and make a pull. I will gap the new plugs to .024/.025
Threw new plugs, all .024 gap. Same issue, breaking up still and stuttering. If I get off the throttle and ease into it, 30%ish TPS, accelerates and is happy. As soon as I get back on the throttle, car stutters again.
its pig rich. that's why its breaking down. there's so much fuel its flooding the pot.
10.2AFR with less than 8psi boost and 10 degrees timing will never burn.
use the VE table to lean out the fuel back to 11.50-11.80 at least. don't be scared to add a little timing as you're on very little boost. that will also help burn the fuel and clean up the pull. your VE values from around 1200-3200 RPM through the transition into boost are huge.
6 Common C5 Corvette Failures and What's Involved In Repairing Them
Slideshow: From wobbling harmonic balancers to failed EBCMs, these are the issues that define long-term C5 ownership and what repairs typically involve.
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph
Slideshow: A modern Camaro transformed into a retro icon, this limited-run "Bandit" build blends nostalgia with brute force in a way few revivals manage.
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked
Slideshow: Cadillac didn't just crash the high-performance luxury vehicle party, it showed up loud, supercharged, and occasionally a little unhinged...
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes
Slideshow: A one-off sports car that looks like a vintage Italian exotic-but hides a C6 Corvette underneath-just sold for the price of a new mid-engine Corvette.
Boosted L33 stutter at WOT 
