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headache

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Hey guys i'm wondering how big of a piston can go in the stock warrior cylinder? i know the fst 446 is an 87mm piston but could you go bigger? this would make the warrior 383cc with stock stroke. I could make my own sleeve if needed but i'm worried about how close the head bolt holes are... someone shed some light on this for me. i'm wanting to build a big bore stock stroke engine..
 
headache said:
Hey guys i'm wondering how big of a piston can go in the stock warrior cylinder? i know the fst 446 is an 87mm piston but could you go bigger? this would make the warrior 383cc with stock stroke. I could make my own sleeve if needed but i'm worried about how close the head bolt holes are... someone shed some light on this for me. i'm wanting to build a big bore stock stroke engine..

http://www.cycleworksracing.net/warrior.htm

Greg has a 89mm overbore piston kit that is basically all the bigger you can go. You bore right out to the head bolts. To make the sleeve fit.
Thing to remember is that you also have to bore the cases when going this big and anything over 85mm bore. Which requires you to take appart the bottom end taking everything out of the cases (crank, rod, all gears, shift shafts, etc.), 85mm bore is the biggest you can go on the stock sleeve. So in my opinion if you have it all appart it doesn't make sence to just go and put in a big bore sleeve and piston as that really doesn't add power like a stroker crank would and for the time and effort you have into already you might as well stroke the crank as well and do it right.
Mickey only has a 87mm piston kit that is used with his stroker crank as they move the piston wrist pin up on the piston because of the longer stroke crank.
 
thanks man,i didn't think about having to bore out the cases. Hmm looks i might as well build a 400 or 446 stroker.. How much compression does the hotrods 400 stroker piston have?
 
headache said:
thanks man,i didn't think about having to bore out the cases. Hmm looks i might as well build a 400 or 446 stroker.. How much compression does the hotrods 400 stroker piston have?

Yeah that whole case boring thing sucks.
10.5:1. It's a flat top piston. The only thing I don't like about the hotrods kit is no overbore piston.
I really like the CWR 460 stroker kit and I think I would try that if I got the chance. The only thing that I don't like is the 12:1 compression piston they use.
I think mickeys kit is pretty tough and has more stroke then any of these kits which will make awsome amount of torque.
 
One thing to as well you can always use the thinner gasket trick to get a little more compression if needed out of the HotRods kit.
 
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