if you go roots the best one on the market right now is the TVS eaton unit, but why bother with roots or centrifugal when you can get a whipple twinscrew that has the low end of the roots and the high end of the centrifugal, yet requires less effort to turn and provides cooler air charge temperatures?

If the whipple is so perfect then why are people even bothering with the roots or centrifugal? There has to be a down side.

Whipples are harder to manufacure, require very close tolerances and so have been traditionally more expensive.

$$$$

Will the Harrop TVS fit on the 370z? If it will with the right parts im going to shoot myself. I bought one for my cobalt and then sold it when i got the 370z..lol.

I had a whipple charger on a 1998 4v Mustang cobra and it made 3psi boost at 2,000 rpm, 4 psi at 2,500, 5psi at 3,000, then 7 psi from 3,500 to 6,000 then 6 psi from 6,000 to 7,000.

In my experience that level of performance is somewhere between roots and cetrifugal. Back when I had it, guys with Vortech and Paxton kits with 7psi were making about 40 hp more than mine (I was getting 375hp at tires), but their peak power was around 6,800 rpm (fuel cutoff = 7,000) where my preak power was at 6,000. So the whipple design does fall off some at high rpm and you do get boost at any rpm (because it's positive displacement), but don't get full boost until you are at 50% or max rpm.

way to kill the thread Phi.

was that one of the old single port whipples or one of the new ones with the redesigned intake side? Whipple went through and changed the front side of the blower to give it the equivalent of a TVS type upgrade. I was thinking of using a KB unit but you would have to buy it used as KB refuses to sell them in a non-kit form. I could only see myself using centrifugals if I used 2 sequential units that would switch over to parallel for increased low end and that would be tricky. I already plan to run wastegate after the blower and an intercooler so i will have more of a turbocharger level of control over it. That way i can pulley the car for 600 and set my boost level with the wastegate for even more low end. My goal is to have my little 3.7L pounding out torque like my friends 6.0L GTO. Then Imma gonna pick on all the v8 stangs in town with a rear bumper sticker that says "what it's just a 6?";)

Oh and to Snakes if you bought it sized for a cobalt it isn't anywhere near big enough for our cars. The blower should have about a 600hp capacity.

Im looking at replacing my m-62 on my stillen 2003 SC with the 1320 tvs. I have talked to Performance superchargers and they will match it to my exisiting stillen kit, The only problem is that i have to drop the compression of the moter to 8.5 , as it will make 16 psig of boost. They estimate 420 rwhp. It will fit under the stage 2 hood. The TVS is a huge improvement over the M 62 and M 90. A lot less heat and more effecant. I turn the m-62 stillen at 10.5 psig boost and its not even 52 % effecent. I have cosworth heads and GTM Sc cams for this project.
A 1320 TVS on a 3.7 would be nice.

I know I have a question and I am guessing many others are also interested in the answer as well. I would love to have a forced induction system (especially since I am at 5500 ft. elevation and am already loosing over 20% from that alone) but to use Ron Popeil’s term, I would like to “set it and forget it”. I would like the highest gains that are safe for the engine. I would not like to have the lifespan of the engine reduced by any significant amount. I do not want to have to take it to a tuner after the initial setup and install and initial tune. Basically I would like the overall reliability to remain while performance was greatly improved. Is this possible? Am I expecting too much? If I wanted 375+ rwhp, should I have bought a car that came that way from the factory? I would love to hear from GTM and Stillen about these questions. Thanks for your time and attention!
John

Do you really need to post the same question three times in the top three threads?

(And 'yes', I have to post my same question three times to make a point)

I would have totally answered that question if you hadn't rudely spammed it across the board. Seriously, that's impolite...

The post was "spammed" to the threads of the epople I was requesting a reply from. GTM and Stillen. I find it interesting how you were offended that you were forced to have your eyes glance over my post two additional times. Doesn't take much to set you off.
john

Honestly, once is enough, the reason people are mad is because they are following these threads, as I am, and its a little annoying to see the same question asked on all three of them. You more or less hijacked all 3 threads and now we have to read the same answer to your question three times just because you are impatient. Think about it.

Yeah, and all it does is get people giving different answers to the three threads, it's like holding three separate conversations with people at the same time.