Topic: changing out manifolds

[cz777]

please dont flame on this one! the TBI intake manifold for MPI intake manifold . why the MPI intake flows better than the other . yes the need for a adopter plate is needed and some dimpling of the lower part of intake under TBI unit . ok gang what do you think of this mod ?   

[sharpxmen]

please dont flame on this one! the TBI intake manifold for MPI intake manifold . why the MPI intake flows better than the other . yes the need for a adopter plate is needed and some dimpling of the lower part of intake under TBI unit . ok gang what do you think of this mod ?   

don't quote me on this one but i think the heads are also different

[chardrc]

main differences without seeing side by side is the TBI manifold has water passages and a smaller bore for the throttle body.

[dwtaylorpdx]

A aluminum block machined would do it,, seems like a reasonable theory.
all the 2.5 heads are the same according to the book at our shop.
Only the early GM engine is different.

Youd have to plug the injector holes on the tbi. and Likely drill holes in
the adapter plate or manifold for the TBI vacuum lines.

Vacuum signal data is likely going to be hit or miss depending on what where and how many....

I would not expect to see much difference, the TBI is basically a pulsed continuous injection system,
and the throttle body is the bottleneck for the most part.

Has anybody tried a two barrel TBI on a modified manifold I wonder?
Should be able to run both injector eggs off one signal, Just need to find the smallest
units possible from a fuel flow perspective since you'd have 2...
Switch to a aftermarket GM computer to run it...

Dave

[sharpxmen]

 that ^ would end up in some serious $$$ - might as well upgrade everything to the later 2.5MPFI (even a 4.0 would fit in that budget) and spend the difference on a vacation in Mexico