Smallest, fastest spooling turbo for 600rwhp?

[BIG CC RACING]

While it didn't make 600hp yet, it did make 506 @25psi. At that point we were getting 25whp per psi, so at around 30psi you would be well over 600hp.

I would like to see the maths for that. A 150hp low comp turbo engine to break normal atmosphere (of 1 bar) gives approx 180 to 190hp. If going positive it then make 25hp per psi you would be seeing 25hp x 25psi = approx 625 plus (not forgetting) the 1 bar normal atmosphere base level of 190 odd making 815hp at 25psi & at 30psi you would be 940hp.

At 506hp @ 25psi which is good power by the way I would calc that as 506hp-190hp (guessed power at atmosphere) = 316hp divided by 25 = 12.64hp per psi.

For those that don't understand power at atmosphere, if a turbo bike makes 250hp at 6psi & then makes 310hp say at 12psi & 370hp at 18psi you can see it makes 10hp per pound of boost so if you subcontract the initial power gain at 6psi of the same 60hp it would be reading 190hp. That is not the aspirated power of the engine though. It is the power the bike makes to get to normal atmosphere from vacuum before then going positive into boost as the turbo is still feeding in air.

As a rule of thumb on petrol a Busa without intercooling makes from 8-11hp & with intercooling from 11 to 14. Other factors such as compression & engine size & turbo size & boost efficiency etc etc will vary that.

 

[juissed]

instant gate pressure and control. u won't over boost either. you do not lose any control, spool-up etc if your using an external air source vs manifold pressure. run the smallest spring you can to make the least amount of boost with

Whats the best way to do it? I use nitrous for my air shifter with a 150psi step down adapter- thinking about just throwing a T on it and feeding it to the solenoids as well.

 

[GNBRETT]

get the good Carolina regulators. u can use N20 plenty do. I prefer co2. mine is T'd

Whats the best way to do it? I use nitrous for my air shifter with a 150psi step down adapter- thinking about just throwing a T on it and feeding it to the solenoids as well.

 

[oldgixxer]

Whats the best way to do it? I use nitrous for my air shifter with a 150psi step down adapter- thinking about just throwing a T on it and feeding it to the solenoids as well.

Don't throw 150psi at the AMS solenoids,stay about 20-30psi more then your highest target boost psi;so in your case you need to regulate that 150psi down to 55-6opsi going to the AMS solenoids.

 

[Busa492]

Good luck with the upgrades! I can't wait to see new vids of you high hp cars.

 

[Kevin Jones]

I told Walter I was using a regulator on the AMS solenoids and he went ballistic "Who told you to do that?". I was like wtf. He said it doesn't need it. I didn't make a big deal about it and didn't say anything but it was Seb that said to regulate down from the 140 I usually use on my co2. Maybe it doesn't need it, I dunno.

 

[oldgixxer]

Um yeah,I'd listen to Seb since he designed it lol

 

[Kevin Jones]

True, but whats the difference between the air shifter solenoids and the AMS solenoids? The shifter solenoid takes the 140 just fine. I didn't look to compare them but they seem pretty close, maybe even same manu. At least the solenoid for my shifter that MPS kit had.

 

[oldgixxer]

Im not sure the exact reason as I never asked,but I was told to use the Carolina regulator and drop the psi. Yes,the solenoids look the same as the air shifter and they most likely are.

 

[FULLTWIST]

I would like to see the maths for that. A 150hp low comp turbo engine to break normal atmosphere (of 1 bar) gives approx 180 to 190hp. If going positive it then make 25hp per psi you would be seeing 25hp x 25psi = approx 625 plus (not forgetting) the 1 bar normal atmosphere base level of 190 odd making 815hp at 25psi & at 30psi you would be 940hp.

At 506hp @ 25psi which is good power by the way I would calc that as 506hp-190hp (guessed power at atmosphere) = 316hp divided by 25 = 12.64hp per psi.

For those that don't understand power at atmosphere, if a turbo bike makes 250hp at 6psi & then makes 310hp say at 12psi & 370hp at 18psi you can see it makes 10hp per pound of boost so if you subcontract the initial power gain at 6psi of the same 60hp it would be reading 190hp. That is not the aspirated power of the engine though. It is the power the bike makes to get to normal atmosphere from vacuum before then going positive into boost as the turbo is still feeding in air.

As a rule of thumb on petrol a Busa without intercooling makes from 8-11hp & with intercooling from 11 to 14. Other factors such as compression & engine size & turbo size & boost efficiency etc etc will vary that.

I believe what Boosted Cycle Preformance was saying was in reference to "at that point". Meaning at 25 psi and 506hp they were averaging 25 hp per 1 psi. Not for every 1 psi throughout the entire range, they hit 25hp, that would be crazy talk. I know it's cool to through stones first, but looking at his other post I bet he knows what he's doing.

 

[Boosted Cycle Perf]

I believe what Boosted Cycle Preformance was saying was in reference to "at that point". Meaning at 25 psi and 506hp they were averaging 25 hp per 1 psi. Not for every 1 psi throughout the entire range, they hit 25hp, that would be crazy talk. I know it's cool to through stones first, but looking at his other post I bet he knows what he's doing.

Exactly.

 

[BIG CC RACING]

I believe what Boosted Cycle Preformance was saying was in reference to "at that point". Meaning at 25 psi and 506hp they were averaging 25 hp per 1 psi. Not for every 1 psi throughout the entire range, they hit 25hp, that would be crazy talk. I know it's cool to through stones first, but looking at his other post I bet he knows what he's doing.

Excuse my being dumb but you have lost me. Lol

Are you saying at 25psi it made 506hp & averaged 25hp per 1 psi? Thus at 24 psi it was around 481hp & at 26psi it would be say 531hp ?

Neither throwing stones or undermining anyone in knowing what they are doing. Its just a matter of understanding what each of us are referring to to

 

[BIG CC RACING]

The reason I ask Fulltwist is because typically the horsepower per psi of boost stays pretty similar on the increments as the boost increases until when the turbo efficiency is affected or the air temp is badly affecting stuff. Good thing about a GTX it can go way past 30psi & still stay efficient, so if you are managing the inlet temp with a chargecooler the power increase between 6 & 7 psi would be reasonably similar to the power increase between 12 & 13 or 24 & 25 etc if the conditions are repeatable.

 

[GNBRETT]

I don't see anyone throwing stones. it was simply pointed out that the Turbo isn't making 25 hp per lb. of boost. I've never seen more then 10-15hp at best per lb of boost. my GT40r made 435 hp at 20 lbs of boost. at 25 lbs. it made 510 hp. so thats about 15 hp per lb of boost. I have a billet wheel in my GT40r as well so pretty similar Turbos as far as power goes.

 

[FULLTWIST]

Big CC, your far more experienced with turbo bikes than I. Not even going to argue or attempt to argue with you. I was referencing my experiences with turbo bikes and there dyno sheets. I'm a believer in turbo systems having a sweet spot were everything comes together, and thus the hp to psi ratio is different. Pluse, the head work could have just began to shine at that 25 psi 506 hp. Never seen a sheet show equal jumps throughout the complete range of boost. Once again, your far and away more experienced than I. I could be interpreting the information wrong. I thought/think the "sweet spot" was what BCP was referencing. I would greatly appreciate it if you showed and explained a sheet and how the psi to hp ratio does not change. I'm always looking to learn, that's why I'm on here. Thanks.

 

[Travis England]

5

The reason I ask Fulltwist is because typically the horsepower per psi of boost stays pretty similar on the increments as the boost increases until when the turbo efficiency is affected or the air temp is badly affecting stuff. Good thing about a GTX it can go way past 30psi & still stay efficient, so if you are managing the inlet temp with a chargecooler the power increase between 6 & 7 psi would be reasonably similar to the power increase between 12 & 13 or 24 & 25 etc if the conditions are repeatable.

506/25 = 20.24 hp per pound of boost but that's not how you do the math

506-160 (stock hp with low compression is about 160)=346. 346/25 psi = 13.84 hp per lb of boost

13.84 is your answer