Billet Injector Blocks
 

While rebuilding the top end, I noticed that a few of the factory plastic injector blocks were cracked.

Am thinking about going with aluminum billet ones instead. Other than Powerhaus, any idea who else might have them?

thanks...

I always thought it strange that these are plastic but then realized that it probably acts as an insulater keeping the intake manifold and the CIS head a bit cooler. Does that theory hold heat?

That's my understanding as well. The billet ones usually have an insulator in addition to gasket to serve the same purpose as well.

+1 on their insulative abilities.

The engine also expands a bit more than the manifold so they also act as stress relievers. For that reason I will be sticking with the plastic injector blocks thanks to my one piece manifold.

Hmm, the billet ones sound like a solution looking for a problem...

-Wayne

Well, the problem in my case is I'm considering porting the head - BA's book suggests 36mm but the factory ones only has 4mm wall thickness so can't be machined.

I'd be interested if anyone had good/bad experience with porting the 930 head?

FWIW,...We always use billet ones as the OEM phenolic injector blocks are very prone to crack.

When (not if) that happens, you get a big enough air leak that creates a severe lean condition and the consquences are very expensive.

Steve, Where do you get the injector blocks? Also noticed those billet cylinders on your site, who makes those?

We carry the billet injector blocks.

We designed those 102mm cylinders and they were made for us, right next door,...:) They were not cheap, but those were made at a time when Mahle could not deliver anything and "necessity was the Mother of Invention".