velocity stage 1 turbo rebuild kit?

vandrexx

Registered
kinda new to turbos but i bought a gen1 busa with a velocity stage 1 kit a few weeks ago, ran perfect until this past weekend when it started to run like crap. checked the bike up and down and found out i have a MASSIVE oil leak coming from the turbo. i'm not absolutely sure on the exact size of the turbo or the part number on it. all i can make out is a/r 42 m24 anyone know of any rebuild kits for this turbo?
 
I believe the stage 1 velocity kits used a gt28 turbo.

Once you undue the nut to take the shaft out more then likely it will not go back together balanced.

It’s worth taking it off and shipping it out to turbos direct in Arizona for a rebuild.

For a bike to run really good, and then all of the sudden not, and leak oil I’d be looking in to other potential mechanical problems. Checking the plugs and doing a compression test is an easy way to asses the overall health of the engine, and if the tune is off.
 
I believe the stage 1 velocity kits used a gt28 turbo.

Once you undue the nut to take the shaft out more then likely it will not go back together balanced.

It’s worth taking it off and shipping it out to turbos direct in Arizona for a rebuild.

For a bike to run really good, and then all of the sudden not, and leak oil I’d be looking in to other potential mechanical problems. Checking the plugs and doing a compression test is an easy way to asses the overall health of the engine, and if the tune is off.

I have and do rebuild bike and car engines, but I am turbo ignorant outside of the basic function of how they work, simple in theory, and not alot to do in parts, but mainly the tune.
Can you explain how/why the turbo itself becomes unbalanced when the shaft is removed? Is the shaft oriented to the impeller so that they are balanced together(much the same principle as balancing a tire)?
I have no hands on experience with turbos, so is there a key way in the shaft? But, then again, how could it be keyed and still rotate to be balanced? How do the shaft and impellar connect?
I'de *assume* that the extremely high rpm's would quickly vibrate it to failure if not balanced correctly.
I never considered the inner assembly much more than an impeller, bearings, and seals on a shaft, and I know that's basically it, I'm just curious about how they are balanced now, and would like to learn something new.
Thanks.
 
so turbo lab will actually machine your compressor and exhaust housings out and fit bigger wheels if you like, or convert your journal bearing CHRA to a ball bearing, or whatever. He will pimp your turbo, whatever you want, within the scope of physical possibility and your wallet, he'll do it.
 
I have and do rebuild bike and car engines, but I am turbo ignorant outside of the basic function of how they work, simple in theory, and not alot to do in parts, but mainly the tune.
Can you explain how/why the turbo itself becomes unbalanced when the shaft is removed? Is the shaft oriented to the impeller so that they are balanced together(much the same principle as balancing a tire)?
I have no hands on experience with turbos, so is there a key way in the shaft? But, then again, how could it be keyed and still rotate to be balanced? How do the shaft and impellar connect?
I'de *assume* that the extremely high rpm's would quickly vibrate it to failure if not balanced correctly.
I never considered the inner assembly much more than an impeller, bearings, and seals on a shaft, and I know that's basically it, I'm just curious about how they are balanced now, and would like to learn something new.
Thanks.
 
Yea, sadly we all have pimps :(

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I’ve heard the same as far as unbalanced, yet I have removed many a cast aluminum compressor wheel and re installed billet, never to have a single issue.
u ever think though.... maybe the turbo might respond better or quicker if it was balanced.... I mention it cause I know ure after Et on the dragstrip.
 
My Velocity Stage 2 leaked until Powerhouse fixed it. Depending on where the turbo outlet oil fitting was placed in the oil pan, the size of the fittings and the hoses, sometimes it doesn't all drain out of the line and it leaks out of the Turbos cold air inlet where the filter is. There was a good amount on the ground, Many times. Especially when it was on the side stand. Not that this is your problem, it's just what happened to me. It would smoke on startup alot until it burned the excess oil out of the turbo. My cold air pipe from the turbo and the plenum interior was filled with oil..
 
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I assume being unbalanced and turning those hundred thousand rpms, you’d see contact with compressor housing very quickly!
u ever think though.... maybe the turbo might respond better or quicker if it was balanced.... I mention it cause I know ure after Et on the dragstrip.
 
I assume being unbalanced and turning those hundred thousand rpms, you’d see contact with compressor housing very quickly!
well.. I mean its not that unbalanced to touch anything... but from what im seeing from KIWIs videos... there is more to balancing than just clearance... know what I mean.. check out the videos KIWI posted
 
ok so i'm trying to take the turbo off to send it to be rebuilt bu i can't for the life of me remove these 2 bolts, any ideas??
it's not that they are rusted, i just can't get to them with anything

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