E38 Corvette DBW Tuning Questions

[gpr]

I am new to the e38 pcm's and dbw tuning in general. I'm curious if you can modify the dbw characteristics, so that it is more responsive. For example when you are giving it 30% throttle that it really is open 30% etc... Is this possible with efilive?

Reason I ask is my dad has a 2010 corvette with ls3, and he wanted to send his pcm off to get a "cow booster", which essentially is some sort of eprom flash and a auto cal. I was thinking I could modify this pretty much everything needed with my v2, but that chuck guy is claiming he has to reflash something in the e38 that efi live can not access.

Is this true that efi live doesn't have the ability to modify how the dbw operates to keep the throttle blade open to the position the peddle is pressed?

[swingtan]

There is no quick answer to this....

Early E38's were basically a 1:1 relationship between the pedal and the TB. However torque limiting may slow down the opening rates , depending on the system involved.

Later E38's may have started to use commanded torque maps, that change the way that the pedal to TB opening occurs. in this case, both torque limiting and 'commanded torque' impact on the opening rates of the TB. To complicate things further, there may also be a maximum throttle opening limit referenced to RPM which might restrict throttle openings below certain RPM points.

Cuck Cow ( of the "COW Booster") has made some additional changes to the ECM that help keep the actual throttle opening in line with the accelerator pedal. I can't speak in detail about the changes, mainly because here in Australia we didn't have any restrictions, but from what I've seen it's a very good mod for the US based vehicles.

What I'd do is to log both the APP (Applied Pedal Position) and ETCTP (Electronic Throttle Control Throttle Position) and see how the two look. If you see the later is lagging the former, then you may need to see what can be done. If there is no lag, then there is nothing to "fix".

Simon.

[gpr]

thank you for the answer simon. It looks like there is quit a bit of torque limiting and power reduction in the tune as well so i think i will try removing most of that and log the two throttle position pid's to see what is really happening, and if it makes much of a difference.

I was also reading and it seems that if you change some stuff to much on these e38's that you can "brick" the pcm. So if you make to many changes the pcm just locks itself up and there is no way to undo it? What things would cause this that i need to stay away from?

[Chuck CoW]

Hey there. I'd very much like to fool with some of the Holden cars with my CoW BOOSTER!.

Your stuff is a bit different than ours, but if you're willing to send me an E38 with a CAL that you like for a vehicle you own

I'll do it for free and ship it back to you so that we can see how it works on your stuff.....

I'd prefer it was a spare ecm so if it acts goofy we won't get you stuck....

Also, I have 60+ E38s and if you have a service # from yours I'd be happy to prepare one

and just do a swap if everything works out nice....

Contact me if you wanna give it a try.
Chuck CoW

[GMPX]

I'll do it for free and shit it back to you so that we can see how it works on your stuff.....

That'll hurt!

[IJ.]

That'll hurt!

Made me LOL

[Chuck CoW]

OH, you're kidding me... Just read it 3 times to see what the fuss was about....

You're right... Could have been painful that way.... I'll just use the post office this time!

Chuck CoW