gen 3 swap into nova, has fueling issues

[Isaak]

GREG STOCK.hpt

I have a friend with a Nova that he just finished putting a 6.0L in from a 99? Silverado (not 100% on that)

He has asked me to modify his tune, changes needed are fuel injector change, I believe they are L96 44lb injectors, part number 12613412, one issue with that is I have info that says the IFR should be 52.47, the engine didn't like that at all, I changed it to 42 and working fine with that with some MAF changes.

The throttle body is a 92mm (not sure what brand) and the owner has indicated it has a pretty aggressive cam, I can get that info as well very soon.

Does anyone with a similar set up have any insight on the tune as it is? Apparently it is modified from a previous owner with smaller injectors and cam.

I just want it in the ball park and I can mess with the fueling changes to make it more drivable (and idle okay too)

The "Greg Stock" file is how the pcm came to me.

[blindsquirrel]

If it doesn't work with the correct injector data, then there's something else wrong with it. Fuel pressure too high, probably. What fuel system? What regulator? What's fuel pressure at the rail with a mechanical gauge? Did you update all 4 of the tables for 'injector data' or only the flow rate?

[Isaak]

Aeromotive a1000 pump and a aeromotive a1000 efi bypass regulator.

Idle psi is 58psi.

I only changed the one table, flow vs kpa.

It's been awhile since I have adjusted fuel stuff.

I appreciate the response so quickly! Thank you!

[blindsquirrel]

GREG STOCK - 12613412 58psi referenced.hpt

[Isaak]

Much appreciated, thank you!!

Been out of the tuning arena for awhile, have to re teach myself a lot! Plus the GP GTP pcm and cobalts were so much straight forward than these!

I am just trying to get it idling and running well enough to drive okay, it is going to get dyno tuned properly.

[blindsquirrel]

Oh, I assumed on the regulator - it is using manifold reference (vacuum hose)? Because even though it's a 'return' reg, if there's no manifold reference it should be set up same as a returnless, with sloped tables instead of flat.

[Isaak]

I've been told by the owner that it is constant 58psi.

[blindsquirrel]

GREG STOCK - 12613412 58psi non-referenced.hpt

[Isaak]

Fuel changes are good.

Have a weird issue, tcc related, revs fine, idles fine, but when coming to a stop it stays revved up, very noticeable, it only comes down to idle rpm once completely stopped and a couple seconds has passed.

I will be creating a scan this weekend to show the spots and make it more clear.

I have looked into the trans setting but me coming from clutch cars, its a whole new world tuning these auto's lol.

BTW, it is a 4l80e.

[Isaak]

LATEST.hpt
drive6.hpl

Finally did some driving, having issues with the trans not shifting the way it should be, when it first manually, it will not move, we suspect the solenoid so he is changing it asap. When he had it in first, I would manually turn off the solenoid, it would then move as it should but would not shift out of 1st (because solenoid is "active" persay... as soon as its deactivated 1st gear is stuck again)

Another issue is it shifts way too early, 3700ish rpm at any tps.

I am currently trying to get his wideband wired properly so I can get it working on the laptop but for now I am dialing in the a/f the slow and tedious way but it idles and cruises fine, just need to pull fuel out at cruise and add fuel up top, least of our worries though.

Appreciate any help given!


Also just realized that the vehicle shift issues could be the direct result due to a code that is up, throttle position... going to talk to owner of car to have that sorted out asap.