Earlier Throttle body on later 2.9

[oughtsix]

I know where an earlier model B2 is. NOw for some reason I think that I read somewhere that an earlier TB from a 2.9 is bigger than the later ones, namely, my 91. I'm not expecting some huge difference, but if there will be a difference, I can go pull the part basically for free. I understood from what I read that this is a bolt on affair. So is it even worth my time to go get it?

 

[IMenriched]

It prolly boils down to personal perference....some say that it is. others may feel that isn't providing enough difference.

the best way to know for yourself, is to just do the swap and note before and after performance. seeing that you can get it for free....all you're out is some time

 

[AllanD]

THE advantage to it is NOT "more power"

The point is to FOOL the management computer by getting "full throttle air"
into the engine without the computer "knowing" that you are at full throttle.

the "Big" TB on the engine simply flows more air than the engine can use so you can "Back off" the throttle and you'll actually feel a bit more power...

Why is this? simple when the computer KNOWS you are at full throttle
it leaves "closed loop" oeration and goes to a fuel map that is much more
rich than ideal for power...

I accomplished the same effect on my 2.9 by the opposite method, I had an '87 and I switched an '88-computer onto it.

Same thing.

but the point is not more air the point is altered computer input.

Frankly I had mine modified to with a positive throttle stop
to prevent it from reaching what the computer considered "full throttle"

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[logicgear]

i have a 90 with an 86' TB on it. works great didn't have to do anything to the computer other then disconect the battery and make it relearn the air going in the intake and it adjusted the fuel mixture. with the extra air going in it seems to be able to control the fuel mixture better my milage went up a bit.