G35 NA stroker with ITBs
The New airbox design will be on display at the PRI show in Orlando. The kits will be available a couple of weeks after the show. Although the ITB's can be used for FI the airbox was not made with this in mind and are not made to withstand boost. You would have to make a custom box for you application. I believe any competent shop can fab up an aluminum airbox for boost, and there are several that show their ability on here everyday.
Neil
Neil
Why not design the box to withstand boost? Then Jenvey would have both the NA and FI market for these ITB's covered with a single design.
because there is no such thing as a one size fits all airbox. The airbox is related directly to the rest of the components, and even moreso in a fi application, so it's best to make one yourself based on your kits specific needs
If the opening for the airbox is at the stock throttle body location (like all the aftermarket plenums used in FI applications), how is FI kit fitment an issue?
not the fitment, rather than the air intake requirements, the pressure rating won't be the same for every kit. If you are doing it on the fly, im sure you can make it work with whatever you are using. Just it won't be simply plug and play. The box however will need to be pressure tested first.
It's a very exacting thing to design a proper airbox. It's not quick, it's not easy, and it's not cheap. I have no clue where the inlet is. I'll say this - if I plunked down the $ for an airbox (I haven't yet as doing so was insanely expensive, so I'll leave it for another time) I certainly would not bother to reuse the stock inlet. That's a huge reason what makes the stock manifold so limiting in the first place. That sorta defeats much of the purpose of opposed ITB's. If it were my design (just thinking out loud, as I've spent literally hours upon hours going over this for my own car), at a minimum, twin entries, in the front, or sides, sort of like an HR, but I'd push the inlets further 'down' the plenum itself. You then have to play with heights, interior ridges, etc to ensur you still can properly balance the ITB's and maintain the right velocity through each inlet. Lok at how NISMO has done it before (which was a Jenvey kit originally, not sure what NISMO uses now though) - they have the right idea with the 380RSC for example (both DE and HR versions used twin entry)
When you put ITB's in an enclosed chamber, you're now also dealing with resonance. Not to mention, you run the risk of limiting the air they can ingest, unlike an open air setup. This resonance is dependant on so many things - not the least of which is air volume, as well as velocity. Every turbo/sc application can differ in this regard, so a one size fits all solution just is not possible.
All this is without even taking the trumpet length into consideration. Change the length (for more peak power, or more low end torque, etc) and the airbox now can go out the window and you revise the design again.
When you put ITB's in an enclosed chamber, you're now also dealing with resonance. Not to mention, you run the risk of limiting the air they can ingest, unlike an open air setup. This resonance is dependant on so many things - not the least of which is air volume, as well as velocity. Every turbo/sc application can differ in this regard, so a one size fits all solution just is not possible.
All this is without even taking the trumpet length into consideration. Change the length (for more peak power, or more low end torque, etc) and the airbox now can go out the window and you revise the design again.
Last edited by Z1 Performance; Dec 4, 2008 at 09:25 AM.
there's a ton of info online about this sorta stuff - sometimes hard to separate the real from the bs, but it's there. My head has been filled with this stuff since January lololol
The slope of the front hood and the front timing cover (its height in relation to how close it is to the hood) might decrease the efficiency of any piping routed straight towards the front ala corvette. This is obviously in regards to a Z, it might work well on a G though.
Well considering the fire order, I think the front inlet will compromise the air going to the rear stacks.
Mostly Im worried about the longterm effects of the box with the funnels, when my car tries to cold start and doesn't turn over, it puffs and fire shoots out. I wonder how long the box will stand for that.
Mostly Im worried about the longterm effects of the box with the funnels, when my car tries to cold start and doesn't turn over, it puffs and fire shoots out. I wonder how long the box will stand for that.
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It does appear so. Are you going to be at PRI? I will take plenty of pics for you if not. This looks different than I expected, reminds me of a civic muffler. I am interested to see how it performs.








Looking forward to checking it out next week!
