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Old 03-29-2014, 05:34 AM   #36 (permalink)
gabe3d
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Quote:
Originally Posted by 1slow370 View Post
being a de is going to push the presure up a lot, they don't flow all that great, the hr stock cams and timing will run a few pounds less on the same blower, and the vhr with it's tremendous overlap will run even lower, horsepower doesn't follow this as well an hr 18psi can easily make more power than a de at 21. a vhr at 12 makes more power than a de at 18. That is all uncammed of course.

Oh it's great and all but I really want someone to try and fit the v7 (apparently they will put the v4 housing on the v2 case now) with it's bigger 60k+ rpm limit and 2"larger impeller. <- if that fits it will be cool. the V7 should bolt to the v3 bracket the volute is just a little bigger or if they somehow fit a T-trim impeller on the v3
Agree with you to some extent. The vhr is a superior engine, has higher CR, bigger displacement and better VE therefore it's natural for the same compressor to create less boost in the manifold, but the net result shouldn't be dramatically different if they have a similar kit and reasonable tune. When you cram air into the engine a lot of variables in a NA engine that were important becomes less important.

Best comparison i can give you is the comparison of the GTM VQ42VHR vs my VQ41DE. Similar displacement, same CR and practically identical FI setup, however i opted for HFC and smaller exhaust for noise. The DE made 512/395@9.4psi while the VHR made 546/411@11psi. Without the HFC and smaller exhaust i made 20/10 more. As you can see practically no difference and my cams have an extreme amount of overlap. Cam phasing/timing is moot since both setup have their advantage and disadvantage. You can also lookup the vortech kit on the DE vs skillen kit on the VHR (both stock), not a dramatic amount of difference in the net result either.

As for this build, granted that they don't run into any slippage problem then i don't see why they won't be able to hit 20psi. The stillen setup as far as minimizing pressure drop is very efficient. But like someone else mentioned, the air to water might be the limiting factor for maximizing power. E85 should help though, so lets see how it goes. I would also love to see the V7 dropped in. The 370z has more room so it might be possible with not a lot of work.
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