My stage 1 turbo bike made 258 HP today
- Thread starter jacks996
- Start date
Good lookin bike. Who's dyno? I'm over in Houston.
That's a tremendous number. What octane gas ? Any other mods to the motor ?
I'm gonna guess stock motor, 93 pump gas, and a 6psi spring.
Servay says...?
Servay says...?
02BusaAndy
Registered
I'm gunna go with 8psi spring....
sanket_420
Registered
very impressive. I likessss 
And a melted motor. Stock compression, with 6psi is on its limits, specially if you live in a place that has that crappy fuel with a lot of ethanol in it. Truth be told, you never get exactly what a springs rated for. When I had a 6psi spring, the dyno, and then later on with my data logger showed an actual boost of 7-7.5psi of boost. When I had an 8psi spring it would log 9, then just tap 10 a few rpm before redline.
Truth be told with stock compression bikes, i don't care who's kit it is, or who tuned it, with 6psi it's not if, it's when it's gonna melt. There's a few people that have gotten lucky. But if you ask someone why they built they're motor and upgraded to a stage 2, the story usually starts off with I melted my motor with a stage one.
Truth be told with stock compression bikes, i don't care who's kit it is, or who tuned it, with 6psi it's not if, it's when it's gonna melt. There's a few people that have gotten lucky. But if you ask someone why they built they're motor and upgraded to a stage 2, the story usually starts off with I melted my motor with a stage one.
I was running 93 octane pump gas and it has turbo pistons and power commander. other than that its stock.
Yes 8psi spring
Even though i have a 8 psi spring you can clearly see my boost gauge is at 10 psi during the run.
Just out of curiosity, why did you do turbo pistons? The rods are the weak point. And if you did it to lower the compression a simple .08 base spacer would of done the trick.
Sorry, but I disagree with this . . . a Gen 1 Stage One with 93 octane fuel properly tuned - and this includes attention to ignition timing - will last years. They will take 8 pounds of boost all day - that is why the Stage One for the Gen 1 Busa normally includes an 8 pound spring. These motors do not melt at 6 pounds of boost, that is simply not true.
Stock pistons are another weak point. The next time you have a stock Busa piston in your hand, look how close the upper ring land is to the exhaust valve cutout - this is where stock pistons fail. Although an .080" base spacer plate is a good idea, it does nothing in regard to this weak point. Turbo pistons - good ones - are always a good idea, as are studs and valve springs. If you have a Gen 2, you would want stainless valves as well. And if you have plans of going over 300 rear wheel, rods.
On the other hand, maybe I've just been one of those lucky ones - for the last 30+ years . . .
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I am curious, what does that kind of power feel like on the street?
Frank,
I disagree with your first statement. But it's my word against yours that people will listen to. I don't blame you, I'd try to make a first time turbo owner feel comfertable too about they're set up knowing theyll probably come back for a motor and turbo upgrade later after it melts. Over on sh.org where more then half the guys on that site have had that scenereo happen that I discribed. Recently there was a guy with a copper 99 that had over 100k miles on it, turbo since 5k miles, stock motor. He eventually waxed a piston just recently. His "when" came around sometime later, but it happend. Even if god himself did a perfect tune, They can still burn a motor by the inexperienced rider chopping throttle too hard and getting back it to it, and the fmu not being able to respond. And frank you know as well as I do that bad gas can melt a motor, but stock compression are even less forgiving. Although I'll say most the people I know that did melt a motor with a stage one did not have a spacer.
And as far as pistons go, rcc sells they're stage 2 kit with a base spacer, and the site clearly says you can make a reliable 300hp with a stock motor, just a spacer. Anymore and they recommend engine work. Motörhead use to make over 500hp with stock pistons. But the rods are known to fail at 350hp. You know that. This last year my bike has been on 14-15psi with a stock motor, just a spacer. I know that's pushing it. But it's held up to the abuse of long highway pulls in the Texas heat.
I would of sold this guy a spacer and told him to save his money for pistons and rods later if he wanted to go bigger. *The bike only made 257, which would still be considered live able on a stock compression bike with a good tune, attention to timing like you said before. So why the pistons?
I disagree with your first statement. But it's my word against yours that people will listen to. I don't blame you, I'd try to make a first time turbo owner feel comfertable too about they're set up knowing theyll probably come back for a motor and turbo upgrade later after it melts. Over on sh.org where more then half the guys on that site have had that scenereo happen that I discribed. Recently there was a guy with a copper 99 that had over 100k miles on it, turbo since 5k miles, stock motor. He eventually waxed a piston just recently. His "when" came around sometime later, but it happend. Even if god himself did a perfect tune, They can still burn a motor by the inexperienced rider chopping throttle too hard and getting back it to it, and the fmu not being able to respond. And frank you know as well as I do that bad gas can melt a motor, but stock compression are even less forgiving. Although I'll say most the people I know that did melt a motor with a stage one did not have a spacer.
And as far as pistons go, rcc sells they're stage 2 kit with a base spacer, and the site clearly says you can make a reliable 300hp with a stock motor, just a spacer. Anymore and they recommend engine work. Motörhead use to make over 500hp with stock pistons. But the rods are known to fail at 350hp. You know that. This last year my bike has been on 14-15psi with a stock motor, just a spacer. I know that's pushing it. But it's held up to the abuse of long highway pulls in the Texas heat.
I would of sold this guy a spacer and told him to save his money for pistons and rods later if he wanted to go bigger. *The bike only made 257, which would still be considered live able on a stock compression bike with a good tune, attention to timing like you said before. So why the pistons?
It is perfectly okay to have different opinions - usually based on different experiences - that is healthy, and it is always good to agree to disagree sometimes. I took issue with your statement that a turbo kit running at 6 pounds of boost is going to eventually melt pistons, that it is inevitable. IMO, nothing can be further from the truth - which I base on the 100s of installs I have done over the years. But then again, I did the install, I did the tune. There are indeed a lot of horror stories out there when it comes to turbos - there are also a lot of hacks, and a lot of irresponsible owners.
I do agree with you that jacks996 could have done just the spacer plate, but he had the cylinder off anyway. That was a good time to put turbo pistons in. And yes, many people have made good hp with stock pistons - which happen to be forged - it still doesn't change the fact that any turbo piston you see has a lot of "meat" between the top ring land and the top of the piston. Why do you think that is? Anytime you see a failure with the stock pistons, there is usually more than an 80% chance it will be right at the spot I described: on the front of the piston, right by the exhaust valve relief. This is where the stock ring land is the thinnest.
One last thing: your statement that I would try to make a new time turbo owner "comfortable" about his new project KNOWING that he will be back for a motor later is ludicrous and irresponsible. You can think that all you want, just please don't ever attribute a statement like that to me. Our track record building and tuning turbos is proof enough . . .
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