3500 Throttle Body

[Scott_68B]

I'm in the process of deciding between doing a hybrid swap to my existing Gen II 3.1 or going with a complete 3500. I'm leaning strongly toward the 3500 swap at this point. Is it possible to swap in the DBW gas pedal assembly to drive the 3500 throttle body? I can't seem to find any definitive answer to this in the archives. This will be going into my MGB.

Thanks

-- Scott

[SappySE107]

I would use the throttle cable setup and not try to wire up a drive by wire. Its ecm controlled based on your actions and what the engine/trans are doing. If you wanted to use the 3500 wiring and ecm and all that, maybe but its going to be more difficult that way than running a different TB that has the cable.

[IsaacHayes]

A ford mustang throttle body is 65mm stock (same size as the 3500) and will bolt up after widening the holes in the TB. You'll need an IAC somewhere, there are GM IAC adapters out there I hear for after market computer swaps since they use GM IACs commonly. The linkage would be perfect I would think for RWD setup too.

That or run a 3400 TB or 65mm billet unit from the store here with the TB adapter. You'll also need the 7x crank trigger external setup here.

[Scott_68B]

Thanks for the replies. Didn't realize the computer was involved..was hoping it was just in the pedal.

-- Scott

[Joseph Upson]

I believe there is a pre 3500 type in a GM truck I believe that doesn't interface with the PCM or can be by-passed for direct connect. I wasn't that interested since I doubt an electric TB will ever be as dependable as mechanical linkage. The store has the adaptor needed to convert to mechanical TB.

What I have been thinking about is using the electric throttle bodies in the exhaust system as electric cutouts, now that would be nice.

[IsaacHayes]

Nah the computer is the whole reason they went to electric I bet. That way it can limit the throttle for automatics when shifting/etc or maybe for things like rev limit and top speed limit, or traction control probably. Much better to control the power of an engine that way than pulling fuel or spark.

Is the 3500 TB a stepper motor or?? I'm guessing it has some electronics inside since it has so many pins. I wonder if it's as simple as hitting it with 12v on the right pin, and it stops once it's at it's limit?

My 3500 TB is cracked open I guess for idle/startup and you can push it all the way closed and all the way open, and then it returns back to the start position.

[3.5MGB]

I'm betting it's the same reason as my toyota yaris. they close the throttle when the auto is shifting to reduce the pressure on the tranny. then slap it back open Least that is what I got from a yaris/vitz racing site. you don't notice it doing that but under certain conditions (downhill just AT a shift point while letting off the gas) you can tell the engine is trying to do something, like it's thinking umm where do I want to be, what gear are we going to , ummm . ok right here. whole thing takes about 500ms or so

[ForcedFirebird]

I'm betting it's the same reason as my toyota yaris. they close the throttle when the auto is shifting to reduce the pressure on the tranny. then slap it back open Least that is what I got from a yaris/vitz racing site. you don't notice it doing that but under certain conditions (downhill just AT a shift point while letting off the gas) you can tell the engine is trying to do something, like it's thinking umm where do I want to be, what gear are we going to , ummm . ok right here. whole thing takes about 500ms or so

1/2 sec is enough to lose a race. I'll stick with drive-by-cable