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Discussion Starter · #1 ·
I have a Procharger F1A, with a 5.73 step-up ratio, 74,000 max rpm. Does anyone know how much horsepower it takes to turn at max RPM ?
 

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SBC Dist phase

I got a F2 procharged SBC with the MSD7531 box. I also have a crank trigger. I start the timing at 35*. Does it need to be phased at 35* or what? I have not ran this engine and will be my first time starting it.
 

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I have a Procharger F1A, with a 5.73 step-up ratio, 74,000 max rpm. Does anyone know how much horsepower it takes to turn at max RPM ?
The hp consumption is the product of a number of things, the blower will consume less power at a given speed if it is operating at a lower boost level (pressure ratio), provided it isn't way off to the right of the compressor map (blower too small for the engine).

That said, a centrifugal blower blower typically consumes the equivalent of 15-20% of your flywheel hp at elevated boost levels. That is to say if you're making 1000hp at the flywheel, the blower input power approximately 150-200hp.

-Chris
 

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You sure your not thinking of a Roots type blower?

So your saying 2000hp at the flywheel an F3 is requiring 400hp to drive?

Personally, I think your waaaay off. You ever take a look at those 3 little nylon style grommets in a Supercharger Stores drive unit?

Blessings..........Ron.
 

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You sure your not thinking of a Roots type blower?

So your saying 2000hp at the flywheel an F3 is requiring 400hp to drive?

Personally, I think your waaaay off. You ever take a look at those 3 little nylon style grommets in a Supercharger Stores drive unit?

Blessings..........Ron.
Ron, I spent many years at ProCharger developing superchargers and systems and have done a ton of blower power calculations and tests. Believe it or not, the power consumption numbers are up there. They use a supercharged big block to run in the big blowers because a naturally aspirated one doesn't make enough power to do the job. The little grommets survive because the torque isn't terribly high. HP is the product of both torque and speed.

-Chris
 

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Discussion Starter · #6 ·
Thanks for the reply. I had heard before that it would be around 150 HP, just don't remember where I read it. I am probably overthinking the whole thing anyway. The reason I wanted to know is to plug the number into the Gates program to find out the correct frequency number to achieve with the cog belt tension.
 

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I have heard 220-325 depending on the boost level is normal for the F1a series of blowers.


Thanks for the reply. I had heard before that it would be around 150 HP, just don't remember where I read it. I am probably overthinking the whole thing anyway. The reason I wanted to know is to plug the number into the Gates program to find out the correct frequency number to achieve with the cog belt tension.
 

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Ron, I spent many years at ProCharger developing superchargers and systems and have done a ton of blower power calculations and tests. Believe it or not, the power consumption numbers are up there. They use a supercharged big block to run in the big blowers because a naturally aspirated one doesn't make enough power to do the job. The little grommets survive because the torque isn't terribly high. HP is the product of both torque and speed.

-Chris
Chris, not being harsh, just expressing a different opinion. I discussed this also with ProCharger (can't remember his name but he's in charge of there racing program) what an F3 would consume in power. He said they were not for sure exactly but said it would be less than 50hp for an F3. I tend to think that's more accurate myself. But I'm always opened minded.

Blessings for the day...............Ron.
 

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I am pretty sure he is right. I say this becuase I have seen a few cars go from procharger to turbo and pickup 100-200 at the tire with the same amount of airflow and boost.

Chris, not being harsh, just expressing a different opinion. I discussed this also with ProCharger (can't remember his name but he's in charge of there racing program) what an F3 would consume in power. He said they were not for sure exactly but said it would be less than 50hp for an F3. I tend to think that's more accurate myself. But I'm always opened minded.

Blessings for the day...............Ron.
 

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Chris, not being harsh, just expressing a different opinion. I discussed this also with ProCharger (can't remember his name but he's in charge of there racing program) what an F3 would consume in power. He said they were not for sure exactly but said it would be less than 50hp for an F3. I tend to think that's more accurate myself. But I'm always opened minded.

Blessings for the day...............Ron.
Sorry if my reply seemed harsh, that wasn't my intention. I just wanted to state my credentials so you would understand that I wasn't just fabricating the numbers. I'll do the math for you tomorrow when I get back in the office and have my thermo book at hand. The math is actually fairly straightforward.

-Chris
 

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Chris, not being harsh, just expressing a different opinion. I discussed this also with ProCharger (can't remember his name but he's in charge of there racing program) what an F3 would consume in power. He said they were not for sure exactly but said it would be less than 50hp for an F3. I tend to think that's more accurate myself. But I'm always opened minded.

Blessings for the day...............Ron.
The actual hp numbers it takes to drive the blowers isn't something that the marketing guys at Procharger care to discuss. Its not that its a bad thing cause all centrifugal blowers take a good bit of power to turn, but that the number starts getting up there as the blower size increases and the numbers tend to scare people a bit. The end result is the big blowers make a ton of power regardless of what it takes to spin them and most people shouldn't worry too much about it.
 

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Chris, thanks for sharing your spread sheet. I was in the energy business for years and worked with the physics of energy and what makes things go round and round for years myself. As you are probably aware there are a number of assumptions that go into these kind formulas. They vary so much that many who work in the industry will not share there methodology because of it's inherently argumentative nature and assumptions. In yours, one that jumps out at me is the .60 bsfc. Todays blown gas numbers would be over 30%, more like 33% improved (.40 bsfc or lower). My very own engine likes high 30's.
I think we will just have to agree to live with our own assumptions and methods to come to a conclusion. But it's always fun to take a peak over each others shoulders once in awhile for no other reason than to keep us on our toes;).

Blessings for the day..........Ron Clevenger
 

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Interesting, I would have figured about 80-100hp for an F1A at full steam.

With a 7.25/3.8 pulley at 7100rpm and F1A I see no belt slip with a spring tensioned 8 rib drive, I woundnt think that drive would turn 200hp but who knows. I do know that the 5.4 F1A takes a lot more belt tension then my 4.1 D1SC thats for sure.
 

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Discussion Starter · #16 ·
Interesting, I would have figured about 80-100hp for an F1A at full steam.

With a 7.25/3.8 pulley at 7100rpm and F1A I see no belt slip with a spring tensioned 8 rib drive, I woundnt think that drive would turn 200hp but who knows. I do know that the 5.4 F1A takes a lot more belt tension then my 4.1 D1SC thats for sure.
My F1A is the 5.73 step-up version and I was going through an 8 rib belt every pass before the cog. I tend to believe the 150 hp number, but 276 hp...???? wow
 

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My F1A is the 5.73 step-up version and I was going through an 8 rib belt every pass before the cog. I tend to believe the 150 hp number, but 276 hp...???? wow
I have had the same belt on my car for around 100 passes, I only replace it once a year because I feel guilty. The ones I take off look like new still. Its a very nicely designed spring tensioner setup with very little tension on the belt.

I have had great luck with the F1A, damn good little blower, would like to try an F1R. But I dont think the drive I have will handle it and no one makes anything better for an LS in an f-body, have to custom make a cog setup if you want one.
 
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