2001 Corvette Supercharged, super rich at idle

[Todd]

I am working on a 2001 Corvette.

Has an A@A Supercharger on it, 1 7/8" ARHeaders, Corsa Mufflers, Rest of the engine is stock.
60 lbs Injectors

Issue I am having is the car is really rich at Idle, I plugged in the Injector Data from A@A web page.

Doesn't seem to make any difference how much I pull out of the VE table, still pig rich.

I am hoping someone here could see what I am missing.

I capped off the SC, and looked for leaks with my smoke machine, didn't have any.

I did an Injector balance test with my tech 2, all seemed okay.

O2 wiring looks good, put new 02's in it, no change.

I did try to tune it the old school way, I left the factory INJ data in and just Changed the IFR to get the LTFT and STFT in shape, which seemed to work, except at very light load and throttle it had a stumble, car would go rich then very lean and then back to normal.

So now I'm back where I started, using the injector data and trying to the fuel trims sorted out and having no luck.

[LSandlteditor]

Match the Default Pulse width with the data they provided....Also, in transient section....lower the Min Fuel Milligrams to 0.10 and give that a try. If you need more help, contact me.

[LSandlteditor]

Also, The IFR table looks to have numbers that are way to large for 60 LB injectors. Are they Rated 60lb at 43.5 PSI or 58 PSI?

[Ben Charles]

Set injector data and don’t mess with it anymore... tune VE table (do the above otherwise you won’t be able to lean out enough fuel at idle and Low speeds)

I know Andy, great guy! If I can help let me know

[Todd]

Awesome, I will try that.

Thank You!

[Todd]

I believe they are rated at 43.5 PSI

[Todd]

So I tried that, but the Injector DATA Only has One table that matches my ecm, so its way richer now after those adjustments.

It won't let post the inj data, but I used the 60 lbs Siemens deka data off of Andy's web site.

So I set the transient to .10 and it made it even richer at idle, factory value was .032, so I tried going the other way, I am down to .006, which seems better but it is still rich at idle.

The INJ data I have only has one listing in min and default pulse width that matches up to my labels in the tune, so I have them both set at 0.125

I must be missing something, just don't know what.

[1BadLS6]

Looks like you raised the transient instead of lowered it from the first file to the second one (.032 to .100). Try transient of .010 instead of .100.

I'm waiting on an A&A kit with Deka 80s for my car and I already have been working on the tune file, and all my research has pointed to a very small transient Min Fuel Milligrams number for these injectors. I also found the data that most people have used, at least for the 80s, is different from what A&A has on their site so you might want to search around here and LS1Tech to see if anyone has validated data for the 60s.

[Todd]

Yes I did, I went the other way now, but it is still rich at idle and light throttle, I'm down to .006 now...

[1BadLS6]

Found this file on the LS1Tech injector sticky, post #21 https://ls1tech.com/forums/pcm-diagn...ta-sticky.html. The numbers are different so maybe something to try.

Siemens Deka 60lbs Data.hpt

[Todd]

Okay, Thank you!

[1BadLS6]

Any update on how it turned out? I'm curious if the injector data from either source was good/close or if you had to go with something totally different

[Ben Charles]

We changed the injector data and works as it’s suppose too..

Often times I see published injector data not work properly.

[jaked4484]

We changed the injector data and works as it?s suppose too..

Often times I see published injector data not work properly.

Can you post the tune so I can compare the injector data? I’m having rich issues also on my 630cc @ 43.5psi injectors at idle on a 3 bar speed density tune.

[Alvin]

Published injector data for those injectors is notoriously bad. The data you can get that you PAY for is even not good. I wouldn't recommend them for most people for that reason.

Ford does have published data for 60's siemens deka. I built a calculator years ago that used ford data and fitted it to GM pressure. You do a lot of extrapolating to get from the ranges ford operates at to GM. See the image attached. The blue lines are ford data. The red lines are what GM uses (58psi range vs 39psi for ford)

Other than that.. with a large injector on a GEN 3 ECM you should zero out these tables found in the transient section.

ECM 2284
ECM 2282

Capture.PNG