A few motor questions

[DCar]

Im not new to boost "have built two AWD DSM's with 67mm or bigger setups" but i am new to boost with bikes. I was told that a stock bottom end can hold around 300whp before it starts to let go. I know I'll need to stright cut the tranny gears, clutch upgrade, arp stud everything and all that good stuff. I wanna stay fairly stock and make this a street/strip bike. I have a few questions about the motor end of things. I'm looking for 300-350WHP

1. How much HP can factory pistons "on aftermarket rods"hold before coming apart?

2. How much HP/Boost can a factory head gasket hold on stock compression?

3. What kind of HP can the factory wrist pins hold up?


Thanks guys any information would be nice. Viva la .Org

-Dwayne

 

[killerrudy]

Well here is what I have gathered from my time and readings here. Answering some but not at all ur ?'s. The factory rods are the weakest link. Reliable up to 300ish. If I were to tear the engine apart to replace the rods, I would replace everything. So, for the sake of arguement, i would say the factory internals are good to about 300 minus the crank and I have read great things about the factory head gasket. Don't quote me, but Greg(boostbysmith) is running just over 400 hp and has stock head gaskets on his. So, any streetable bike no worries there. A drag bike making enough hp to make baby jesus cry be a different story.

 

[_WOLFMAN_]

Actually Greg aka boostbysmith on his original Gen 1 Turbo Busa believe he did Rods, Spacer, Adjustable Cam Gears and Head Studs but still running factory pistons and makeing 400+ hp
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[trefling]

Dude, before you going running 350rwhp you should try and see if you like what 225rwhp feels like. I wanted (and did) build my bike to 400rwhp and to be honest 225 scares the hell out of me. This is my first turbo bike but not my first turbo car. 500-700rwhp on a car is nothing to the feeling of 225-250rwhp. Honestly it's pretty darn intense and it really made me rethink how much power i really wanted.

But as the previous dude mentioned you might as well replace everything if you have the motor apart.

 

[POWERHOUSE]

Im not new to boost "have built two AWD DSM's with 67mm or bigger setups" but i am new to boost with bikes. I was told that a stock bottom end can hold around 300whp before it starts to let go. I know I'll need to stright cut the tranny gears, clutch upgrade, arp stud everything and all that good stuff. I wanna stay fairly stock and make this a street/strip bike. I have a few questions about the motor end of things. I'm looking for 300-350WHP

1. How much HP can factory pistons "on aftermarket rods"hold before coming apart?

2. How much HP/Boost can a factory head gasket hold on stock compression?

3. What kind of HP can the factory wrist pins hold up?


Thanks guys any information would be nice. Viva la .Org

-Dwayne

The stock bottom end of a Gen 1 Busa will go to about 380 rear wheel before it ventilates your cases. This number can vary depending on load, so it it common to leave a margin. Most builders will recommend no more than 300-325 rear wheel on stock rods. You don't need to do anything to the tranny, although undercutting the gears and running a heavy duty output shaft is wise, as your house is only as good as its foundation. Yes, good clutch springs are necessary and possibly a lock-up, depending on the level of power you intend. You don't absolutely need to "arp stud everything", but the cylinder studs you definately want to do. The arp 10mm cylinder studs are the best stock-threaded studs, and will take you over 400. If you are thinking about 500 or better, going with the 1/2" studs or bolts is a must. You will find it is not about whether the head gasket is stock or Cometic, as both are good quality MLS. It is about the studs. Either head gasket will hold 40 pounds of boost. And as you have already heard, the stock pistons and pins have gone over 400 . . . whether they will go higher than that reliably remains to be seen. Wossner makes some great turbo pistons, and you can rely on them 600+ . . .

 

[DCar]

Dude, before you going running 350rwhp you should try and see if you like what 225rwhp feels like. I wanted (and did) build my bike to 400rwhp and to be honest 225 scares the hell out of me. This is my first turbo bike but not my first turbo car. 500-700rwhp on a car is nothing to the feeling of 225-250rwhp. Honestly it's pretty darn intense and it really made me rethink how much power i really wanted.

But as the previous dude mentioned you might as well replace everything if you have the motor apart.

I know what you are saying and I'm only looking for 250ish for the street "maybe alittle less" and about 300-350 for the track. I want a nice street bike but be able to switch over the maps and go run at the local 1/8mile and have alittle fun.

After moving up from a modded R1 "first bike" to the busa, after about a 2-3weeks i wanted move power. It takes a ton to scare the **** out of me "coming from a dragracing back round div.3" but I know my limits.

The stock bottom end of a Gen 1 Busa will go to about 380 rear wheel before it ventilates your cases. This number can vary depending on load, so it it common to leave a margin. Most builders will recommend no more than 300-325 rear wheel on stock rods. You don't need to do anything to the tranny, although undercutting the gears and running a heavy duty output shaft is wise, as your house is only as good as its foundation. Yes, good clutch springs are necessary and possibly a lock-up, depending on the level of power you intend. You don't absolutely need to "arp stud everything", but the cylinder studs you definately want to do. The arp 10mm cylinder studs are the best stock-threaded studs, and will take you over 400. If you are thinking about 500 or better, going with the 1/2" studs or bolts is a must. You will find it is not about whether the head gasket is stock or Cometic, as both are good quality MLS. It is about the studs. Either head gasket will hold 40 pounds of boost. And as you have already heard, the stock pistons and pins have gone over 400 . . . whether they will go higher than that reliably remains to be seen. Wossner makes some great turbo pistons, and you can rely on them 600+ . . .

WOW, thanks guys. I'm not looking to go over 350HP but I just wasnt sure on a few things motor wise. The bike will be getting a lockup clutch and the head studs for sure. I've always wanted to do landspeed at maxton or texas for years now but I can handle just beating up on the local guys at the strip. Thanks for all your informantion, you guys are the best in the buisness.

Powerhouse, I'll def. be coming your way once the build starts for parts and info. Thanks a ton.

-Dwayne

 

[Gixer]

Hi,
Recently happened to me that the bike is mixed water and oil in a way that erupted two plugs in the head and the water mixed with oil.
The head, cylinder, gasket is not damaged.
I assume that the thermostat is blocked?
Do you remove the thermostat on a turbo bike?
Thanks

 

[BA BUSA]

Welcome to the board.
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