5.HOE said:
wouldnt the blower become a restriction for the turbos??? how does that work??? do they gut the blower out?????
No. We actually have been getting a lot of questions/crap about this. (BTW I'm not saying that you're talking crap about it, just saying. O0)
Here's how it works:
You do NOT want to use a smaller blower pulley, we tried that with bad results. And yes the blower is totally stock and intact and functional. And no, we haven't tried a bigger blower yet.
Here's how the whole compound boost things works, and why it may be somewhat of a restriction, but also why it can still work in this case.
All boost is, is positive manifold pressure. This means that the turbo or blower is forcing so much air into the engine, that the engine can't keep up, and the air backs up. This buildup of air is the pressure that is measured and displayed as boost. Now, the roots supercharger on this car would normally be spinning fast, creating a vacuum that would need to be fed by air, that's the induction. By feeding that supercharger with the boost provided by the turbos, you create a compound system, one that doesn't rely on pure atmosphere for boost. This system spools faster, and creates more boost than is possible with any other system.
The stock pulley ratio creates about 10 lbs of boost or so on our car, maybe a tad more. When this is combined with boost from the turbos, it multiplies it to create a higher level of boost. In this case it would be a multiplication of 2.5, so 10 pounds from the turbos would be 25 pounds at the engine. Now, a big blower at low boost would be optimal due to the amount of air that can flow through it being greater than that of the stock Eaton, but by supplying the air to the blower, you make it work less because it doesn't have to "suck" as hard to create the boost. It is still an object that the air has to travel past though, and in that sense, it is a restriction. But this kit will work with or without the blower, so it's up to you. All I have to say is - I would keep the blower. The boost and throttle response is just awesome.
Here's a shortened, easy version. Basically, what this system does is create a REALLY REALLY efficient roots blower. It does this by creating a ton of boost, while only spinning the blower fast enough to create 10 pounds of boost. This reduces heat and restriction.