4.3l Intake Manifold

[halffast]

I'm replacing a 1989 4.3 with a newer short block that has a balance shaft. The original non Vortec heads are installed. The 2bbl Intake won't fit because the balance shaft hits the manifold.

Is there another manifold for this application?

What about the TBI manifold from the Astro Van? Basically, I think I need something from a pre - Vortec - balance shaft engine.

Any advice?

Thanks,

Bob

 

[Bondo]

Re: 4.3l Intake Manifold

I'm replacing a 1989 4.3 with a newer short block that has a balance shaft. The original non Vortec heads are installed. The 2bbl Intake won't fit because the balance shaft hits the manifold.

Is there another manifold for this application?

What about the TBI manifold from the Astro Van? Basically, I think I need something from a pre - Vortec - balance shaft engine.

Any advice?

Thanks,

Bob

Ayuh,.... That's of No use to you.... Is it just the heat shield, riveted to the bottom of the manifold hittin',..??

I'd be temped to pull it off, 'n modify it...

 

[halffast]

Re: 4.3l Intake Manifold

"I'd be temped to pull it off, 'n modify it..."

Well, yes it is the heat shield. In fact I had already removed it and the manifold sits down. The lobes on the balance shaft appear to be shaped so as to clear the underside of the manifold below the carb. However, in positioning the manifold front to back there appears to be some interference unless the manifold was centered exactly over the bolt holes.

I assembled it this way and fired it up. I cranks smoothly and quietly but on start up there is some significant noise (clanking). Because of the initial clearance issue I suspected the balance shaft. If this manifold is in fact OK to use I'll have to look further into the noise issue. Worst case is to remove the intake and check for wear or scrapes on the balance shaft.

Any other opinions or comments?

Bob