MoTeC Global Forum

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

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.

Ive Read it

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

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.

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.

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.