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I'm thinking it would require alot more fuel pressure,
once it gets into boost, than if it's mounted above the supercharger.(normal atmospheric)

Quote:

Originally Posted by HTRDLNCN (Post 3255788)

Why not mount it under the supercharger so you can get more air density and not have fuel going thru the blower?

Quote:

Originally Posted by JIMKID Motorsports (Post 3255946)

it cools the rotors

You are correct that it cools the rotors. Not only that, but the fuel actually helps to seal the supercharger.

Quote:

Originally Posted by HTRDLNCN (Post 3255979)

I would imagine at the speed the air goes thru the blower it wouldnt need additional cooling?

Anytime you compress anything, you will raise the temperature. Pretty much no matter what it is, whether it's a gas, liquid or solid, if you raise the pressure you will raise the temp.

Quote:

Originally Posted by JaayTeee (Post 3256130)

I'm thinking it would require alot more fuel pressure,
once it gets into boost, than if it's mounted above the supercharger.(normal atmospheric)

You are correct. The injectors will flow less if they are in pressure rather than in vacuum. The vacuum will actually help to pull the fuel out of the injector. In some instances, moving the injectors from above, or inlet side of, the blower to below, or outlet side, it will require going to a larger injector.

Eddie

Thanks for the info and the answers,
my only hands on experience has been with
centrifugals/efi on drag cars and we always ran fuel after the blower
and never needed fuel to cool or seal the blowers even at 25+ psi/1000+hp.
Guess roots blowers are a whole other ballgame, :)

As for fuel injectors we used boost referenced regulators which
raised FP as boost went up keeping the flow from the injectors
same.

Finally got around to taking some pics of the finished product. I hard coat anodized everything including the fuel rails, injector plates, carb adapter, etc. I'm pretty pleased with the way it came out. I didn't think it would look that good polished against a black blower.
This will also bolt right up to a roots blower or top entry Whipple, not just the PSI.
Thanks. Enjoy.
Eddie

Looks good Eddie what power package is it going on/in?

Looks awesome Eddie!

Those turned out nice Eddie. I always amazed when I see the PSI blowers just how big they are.

Quote:

Originally Posted by NEVERSATISFIED (Post 3343668)

Looks good Eddie what power package is it going on/in?

You know......I'm sad to say that I don't know. The owner just sent the blowers to me so I could get started on building the injection. We have talked about so many different options, that I'm really not sure what they are going on. I believe we are using some existing engines. Maybe he will chime in and shed some light on it. Thanks
Eddie

Quote:

Originally Posted by boatfreak (Post 3343771)

Those turned out nice Eddie. I always amazed when I see the PSI blowers just how big they are.

They are incredibly big. I'm always amazed myself. I remember the first time I saw one. I always refer to it as a small block sitting on top of a big block.
I took the first one I got my hands on to play with and put it next to a 3.3 L Whipple. It was like comparing a Weind 177 to a 14-71. Just no comparison in size. (certainly not a knock against a 3.3 Whipple)
Eddie