pulling tractor guys do it and they make crazy power in those John Deeres and IH's

 

There is a girl in my town that has a RX7 with what I called a 2 step turbo.Off the line it takes off real well then when the car changes to 2nd hold on-that car really takes off. I did not get a real close look at it but it has a valve that opens and lets the extra boost from the 2nd turbo go at a certain RPM.Works really well for launches.

 

Why not do a compounding boost setup while you're at it. You can have two different sized turbos, but you could possibly get the benefit of more boost. Also you could use step intercooling between the turbos to really cool off the air.

 

compounding turbos are for guys that need the presure to make the power. a t72 will push 40psi just fine and still be efficient. with a 408 it will take a large volume of air to make the power, not more presure(not more than the 40psi a 72 is good at).

 

jim this set up if for a huge cubic inch monster that can eat air.
how are you going to keep the larger turbo from over powering the smaller one?
when that valve opens the smaller turbo just lost a huge amount of thrust that the larger turbo is now taking away from it.

 

I believe that both turbos are the same size. One turbo will be isolated so exhaust gasses from both banks will spool one up quickly for low boost setting then both spooling for high boost. I think it will work but will be a challenge.

 

right click save

equal length manifolds would u give u better spool and power than logs.

 

i dont doubt that there would be some top end power to be gained but i question the quicker spool time. in my mind the smaller single head pipe will have more velocity and get the turbo spining quicker but restrict it a little up top.

i feel i have been prety sucessfull with the log manifolds and i dont see the need for a multitube header much less an equal length set up. geting 2 turbos of sufficent size(t72's) under my hood plumbed in the easiest way possiable will give me more hp than i will ever know what to do with.

 

Link no work.

 

http://videos.streetfire.net/video/7...34A79A3BD8.htm

3 rotors 3 turbos. that should be nuts