i finally measured my piston, and as i thought, 68mm(the guy i bought it from said it was a 240). So i decided to make it bigger. I want to get a 72.5 mm big bore piston and i was wondering if a +4mm stroker would b compatiable. Are they generally universal(piston and crankshaft)?
+4mm Stroker and a 72.5mm piston?
- Thread starter McKee
- Start date
Why would you go with a 72.5mm piston?
Generally most big bore kits come with a standard size 72mm piston.
A +4 mm stroker is a popular upgrade as long as you have the cylinder ported to match. Once you've done a 240 kit on a +4 mm stroker you've got as much stuff as you can get (without going rediculous) so you better be happy with the end result because there isn't much more to do...
Generally most big bore kits come with a standard size 72mm piston.
A +4 mm stroker is a popular upgrade as long as you have the cylinder ported to match. Once you've done a 240 kit on a +4 mm stroker you've got as much stuff as you can get (without going rediculous) so you better be happy with the end result because there isn't much more to do...
you can't use that big of a piston without a big bore sleeve or a big bore cylinder kit.
and the crank will work with it, but you're going to need porting and head modifications to make it work, and have the cases trenched as well.
If you're at a 68mm piston, you're going to need to have the cylinder resleeved or replaced anyway
and the crank will work with it, but you're going to need porting and head modifications to make it work, and have the cases trenched as well.
If you're at a 68mm piston, you're going to need to have the cylinder resleeved or replaced anyway
yea that cylinder will not take a 72.5 mm piston...and sounds like it has no bores left in it either
i was planning on takin the whole cylinder to a machine shop and have it bored, not buy a big bore kit. I was figureing a 72.5mm piston cuz the bigger the better. I was also planning on havin it ported, i just need to find a place for all that stuff. What is trenching the cases?
A stock cylinder can take a 73mm piston as long as it has the correct sleeve. The factory sleeve cannot take a piston that large.
Wiseco makes a 68.25mm piston. I have a top end bored fresh out in the garage right now on 68.25mm but 68.25mm is the absolute last bore.
Wiseco makes a 68.25mm piston. I have a top end bored fresh out in the garage right now on 68.25mm but 68.25mm is the absolute last bore.
Trenching is removing a small amount of metal from the inside of the cases to allow the longer stroke crankshaft to turn.
yea, i read about needing to have the head machined to allow for the extra length in the crankshaft.
Yeah and believe me, bigger isn't always better. The bigger your piston, the less bores you can fit. And a 72.5 isn't the best size for you. I would get the 72mm. I run the +3 stroker and a 72.5mm in a Vito's big Bore with local porting and I'm very happy with the results.
