GM DBW Throttle

[Martin]

Hi,

Ive read that the GM DBW throttle`s are not the strongest and that the gears driving the throttle are fragile. Is this of any concern when deciding what DBW throttle to run on a 550Hp LS2 to be used in Offroad racing? The intake is OEM so GM would be preffered but not if it will decrease reliability.

My other option would be a 84mm VDO. Any suggestions or comments?

Martin

[figgie]

Heard or seen?

I have heard lots of things and each one I take with a granual of salt. I have yet to see any real failures.

[Martin]

Ive Read it

Have you used GM DBW units? what do you think?

[figgie]

Yes

in particular the GM DBW off the 2006 Chevrollet Corvette and the E-Throttle pedal off the same car as that is the same size DBW they use on the LS7 based Corvettes.

Works really well for such a big throttle.

[MarkMc]

We have found this in testing (Ask Peter Swinney, haha) but it was mainly the very early smaller throttle bodies (76mm I believe). The gears are weak and do not seem to take any real abuse. I also had the motor windings in one of these DBWs fail in the middle of a rally. I think the later versions of this throttle body were much better and have not seen a gear failure for a number of years.

The later 80mm throttle bodies appear to have no such problem and we have a number of these on customers cars. Figgie, you will notice the shape of the throttle bore at low throttle openings is quite complex, allowing the throttle to act like a smaller one at idle and light loads, you see this a lot on modern throttle bodies.

If you were in Australia I would suggest the Ford BA/BF DBW throttle as they seem the be failure free....more or less opinion though.

[figgie]

MarkMc

Yes, I saw that it is not like a regular TB. It is machined to open a bit at a time. This TB has about 110 degrees worth of opening. I always found the opening while in the lower section curious and assumed that is how they keep such a big TB behaving nicely at low TP.