SC, just because I responded to your thread doesnt mean I like you

 

I know about all of that, I am at 10 psi now.

 

 

Cool, I don't think you will have any problems with your VHO engine, I hope.

 

Wish I could be of some help, but I just opted to get the D1 the first time.

 

The bottom line is the D1 is it has a more efficent impeller and at lower rpm it is able to move a higher volume of air. With the larger displacement engines the larger volume of air is neccisary make the boost more impacting in the lower power band. For that guy who said boost is boost.. try driving a deisel with little turbo.

Psi is not just psi. Psi is a measure of actual delivered pressure at a specific instance and the mass of air or volume.. measured in lbs per minute or Grams per second actually is the number you need to know your true efficency. The P1sc is able to deliver a fairly significant amount of air but it is not nearly the volume the D1 moves.


Bottom dollar the D1 is a more efficent unit unless you are running a 4 popper or v6 that can't flow the cfm

 

I have seen a P1-sc make over 500rwhp on a 6 liter. then I have seen a d-1 make the same power at a lower boost level on the same truck. The d-1 flows more air while putting relatively the same amount of stress and load on the engine. The thing that you have to consider is your engine big enough to support and use all the air the d-1 is going to flow. When I looked in to puting a pro-charger on my truck i was going to use a p1-sc because the 4.8 was not going to be able to support that kind of air flow a d-1 would give. It would have been better off with the smaller, yet efficent p1-sc.

So big motor = Big blower.
little motor = little blower.

or just get a turbo and actually make some power

 

Thanks guys. That is the input I was looking for.

 

I can add a little more here. Given the same platform with just swapping the compressors the D1-SC is worth about 17% more peak power than the P1-SC at the same boost. The D1-SC's helical impeller is most of it but the D1's also have better bearings to handle the higher powered applications that they are used in. The peak air flow of the units is not much different...the P1 actually does a little better in the lowend but the D1 takes off at around 3500 rpms. The case and volute shapes are exactly the same though so if you have a P1 and D1 will drop in. Some people have sent their P1's back to ATI to have them converted to D1's but at what cost I don't know.

 

just checked with ATI and I think they said it cost like $1800.00 to upgrade my P1SC to a D1SC. I don't know if the gains are worth that much I might wait till the P1SC needs to be rebuilt and upgrade it then.