Couple of questions. Assuming (hoping) nothing breaks on my truck in the near future, I'll be getting all of the parts for the twins within the month. So far I have a primary off a cat 3406. It has a 72 compressor and a 88 turbine with a 1.32 a/r. The price was right at free-ninety-nine so I picked it up. I also have begun to fabricate the hot pipe using schedule 40 3 inch and I'll be cutting out my flanges tomorrow. I figured my primary turbo choice should be a decently spooling setup since i'm only running 5x.014s.

I was wondering how much boost there is between the primary outlet and the small turbo inlet. My turbo has a goofy flange on the compressor outlet. Instead of dealing with finding the matching fitting, I figured I could cut the end of the flange off with a hacksaw and simply use an intercooler boot instead of the traditional vband with o- ring

 

You could see upwards of 40psi between them. I would weld a few beads around the outlet of the housing so the hose won't blow off.

 

Cut the ears of the flange as close as possible to the housing and then grind flat with a flap wheel. That should save you some room on the amount of area which the hose has to clamp to. If you end up needing it you can always add a strapto keep from blowing boots.

 

Thanks, Ill do both. Next question: I know that I need to upgrade to a better exhaust manifold down the line, but for now I'm just going port match and use the stocker upside down. When I upgrade to another manifold, will dimensions match up? As much as I love to follow whats been done and proven.....I'm going to be going a different route when mounting the primary and I'm working out mounting brackets since I don't trust all that weight just off the manifold alone with the beating my truck takes. Thanks again.

 

stock manifold works fine, dimensions should be close enough to not be a problem