sharpshooter

iTrader: (9)

If these two prochargers were pullied to have the same peak boost,on the same engine and spun to the same engine rpm would their Dyno graphs(power curves) look the same?

ScottyBG

I would expect the larger compressor to have a softer boost/power curve early on, then gain faster at higher RPM. The smaller compressor, the D1 should be more efficient at lower boost levels, so I would expect better bottom end.

If you had them both pullied to produce 12 PSI at 5K RPM, I would expect a given point like 6 PSI would come lower in the engine RPM range like 3K for the little guy vs maybe 3.5K for the larger compressor. The larger compressor, F1, will be pullied to turn slower at the same engine RPM, for the same peak boost, because it moves more air per revolution. The reverse of this is the smaller compressor will be turning faster for the same engine RPM, and will start to build boost sooner. I've not actually A/B tested 2 compressors like this, but physics should support my above thoughts. Does that make sense?

ScottyBG

Actually I think I'm wrong in my last post. I assumed the F1D was bigger than the D1SC, since the F1 series is normally the larger Prochargers. What I said would be true of the other F1 models but not the D. I looked up the specs on the compressor wheels, the D1SC and the F1D are same compressor wheel, only the F1D is geared differently, so they would have the same dyno graphs, as the compressors are the same, the only difference would be the pullies. Honestly they are pretty much the same unit except for a gear in the housing. The compressor wheels would be spinning the same speed, and the overall drive ratio would be the same, just your would need to use pullies, to make up the difference in internal gearing. You would have the same "final drive ratio" in both cases.

sharpshooter

iTrader: (9)

Thanks ScottyBG!

Blown06

iTrader: (32)

It might be wise for one of use to call procharger to actually confirm what you are saying. Are you saying that they have the same compressor wheel because the physical size dimensions are the same? If so, the wheel could be the same size but fin design be totally different. Also, I wonder if the volute is similar between the two.

My hang up is this, why would procharger spend money to make the F1D if it was exactly the same as the D1sc?

sugarking

agreed

f8lvenom

F1D is a D1SC on steroids. Flows more and higher step up ratio. F1D is a beast down low, perfect for a street/strip car.

BADMOON

I would say stock cubes/bottom end use D1sc. Built motor go F1

stevieturbo

IMO...always choose the bigger one.

When you go small, in a few days, weeks, months you'll want more and wish you went bigger.