I have a Union Bay Racing, Billet 900 top end for sale.
This is a used top end that I took off of a M7 that I just purchased for a turbo project. I did not ride the sled before I removed, other than to load it on the truck.
It appears that at one point, it had gotten hot (most likely an air bubble in the cooling system) and smeared one of the pistons. I cleaned the bore with muratic and acid and ran a ball hone thru bore cylinders. I removed less than .001". There are a few marks in the bores but you can not feel them with your finger nail and they are below the rings in the skirt area.
It also appears that at one point the previous owner lost a ring but must have had the sleeve replaced. I'm guessing he lost a ring due to a couple of marks in one of the domes.
I have one good usable piston but it will require one new one. Fastrax, who now owns UBR, sells pistons for approx. $210. It will also need one inner o-ring that goes in the groove on top of the sleeve. I have been told by Fastrax that you can also get .5 mm oversized pistons and simply bore the sleeves if need be. I personally would put a new piston in it and run it.
The domes are 14:1 and should not require race gas (maybe a mix at lower elevations)
This is a bolt on kit, uses the stock base gasket and does not require case mods. It also uses the same pistons as the UBR Polaris 900 kit, but with a little clearancing on the one of the skirts (with a file) so if you know someone with a spare piston, it might be even cheaper.
Asking $500 shipped to the lower 48
I also have a set of ceramic coated SLP twins and a Boondocker box available if someone is interested.
Thanks, Mike
This is a used top end that I took off of a M7 that I just purchased for a turbo project. I did not ride the sled before I removed, other than to load it on the truck.
It appears that at one point, it had gotten hot (most likely an air bubble in the cooling system) and smeared one of the pistons. I cleaned the bore with muratic and acid and ran a ball hone thru bore cylinders. I removed less than .001". There are a few marks in the bores but you can not feel them with your finger nail and they are below the rings in the skirt area.
It also appears that at one point the previous owner lost a ring but must have had the sleeve replaced. I'm guessing he lost a ring due to a couple of marks in one of the domes.
I have one good usable piston but it will require one new one. Fastrax, who now owns UBR, sells pistons for approx. $210. It will also need one inner o-ring that goes in the groove on top of the sleeve. I have been told by Fastrax that you can also get .5 mm oversized pistons and simply bore the sleeves if need be. I personally would put a new piston in it and run it.
The domes are 14:1 and should not require race gas (maybe a mix at lower elevations)
This is a bolt on kit, uses the stock base gasket and does not require case mods. It also uses the same pistons as the UBR Polaris 900 kit, but with a little clearancing on the one of the skirts (with a file) so if you know someone with a spare piston, it might be even cheaper.
Asking $500 shipped to the lower 48
I also have a set of ceramic coated SLP twins and a Boondocker box available if someone is interested.
Thanks, Mike
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