Twin Manifold - Carby Insulating Blocks

[Rod]

Hi All (again),

Seem to be asking alot of questions of late.

I have a twin carby manifold. Do you need to use the bakelite insulating block with these manifolds like singles. If so the studs would not allow me to put the carby's on as they are way to short.

Cheers


Rod

[HYSTERIA]

Hi Rod,

I have this set up on my car and did not use the spacers due to the fact that the manifold was polished and it looked a bit funny. Mine seams to run fine without them.

cheers
Jason

[EJ_Dave]

Rod,

if you're running extractors the inlet manifold won't get as warm as the original with the standard exhaust manifold bolted to it and you shouldn't need the insulators.

You may need to modify the accelerator linkage a bit though because the carby will sit slightly lower. On my car (EJ) this caused part of the linkage to hit the extractors before I'd reached full throttle. All I needed to do was shorten the vertical link bit and it was sorted.

Cheers,

Dave

[Rod]

I've just finished reading a book on small block chevys and ways to improve their performance.

One point was to put in / increase size of carby spacer to increase HP.

My question then is, what is the main purpose of the "insulating" block. Was it put on a standard manifold to assist flow hence some small gains in HP?

Rod