GY6 Big Bore Kits and "P" Head Discussion By budvoss (Read 14,025 times)

[sprocket]

monstergy6

You need to measure the height of the head... the P engines typically have a 73.5mm high head, the cam chain has one extra link in it.

[monstergy6]

I have take some photos check them out, all the 1P57QMJ I have ever seen have had these dimensions, the photo is the same head we sell and use on all our builds.

[monstergy6]

budvoss, that engine model number is different, I have not seen one of those, just do some measurements as sprocket suggested.

If your head height and bolt spacing is different to the photos I just posted, then you will have to find a different setup. Let's see what your measurements come out to.

[sprocket]

I'm not doubting you.. there are some 1P57QMJ with a 73mm head ...longer cam chain

Why they should be different I have no idea...

[budvoss]

I managed to measure across head bolts diagonally and its 3 inch's. . That is all i can do till it gets a little cooler ,then i will pull engine head and jug.
thanks

[trancebear]

Bringing up one from the past. I just bought a new 1P57-QMJ engine complete though with a cracked rear part of the case that happened during shipping for $75 shipped off eBay. I intend to take the piston with block, head assy. from this and put it on my standard 157-QMJ. My valve seals and my piston rings leak so I feel this is a good deal. Will I have to install a longer cam chain or just use the one from the donor motor? Is there any challenges that I may not have planned for? I purchased a new gasket kit. I like the higher compression and larger valves of this new engine.

[buford1488]

call scrappydogscooters.com..............................cant beat his price's........................

[trancebear]

Oct 30, 2011 6:15:48 GMT -6 buford1488 said:

call scrappydogscooters.com..............................cant beat his price's........................

My 2nd order with them they sent the wrong part and shorted me on the other, giving other venders a try.