4mill and head ?

[breastman569]

So it's at the end of dune season and on last weekends trip I noticed I need to change out my shifter shaft. In doing so I figured its now time put a 4mill stroker in it while I have the cases apart.

I have an 86 with a p&p and what I think is a 66.5mm might be 66.75mm idk. Also the head is a stock Paul turner that has been domed and milled with cr250 head gasket. I am running an air box eliminator boysen rad intake a 38carb.

What I don't know is what cc my head is. My question is with this 4mill it says I have to dome the head 2mill, but I'm thinking of running a cool head. If I do what cc dome should I get? Also I do run 100race gas.
Thank you,
Ryan

[Langbolt]

If your Cylinder isn't Ported for a 4mm stroke you're wasting your time. STROKER cranks in a 2-stroke are not a BOLT-ON upgrade....they have a bunch of issues that you'll have to address.

Spacer-plate thickness

Rod Length

Dome Squish & Volume

Port Timings - Exhaust & Transfers

:D

[cdrookie]

also you don't have to split cases to change out the shifter shaft.

[Langbolt]

X2

All you have to do is remove the Clutch cover....That's the side it comes out of.

No need to split the cases

:D

[breastman569]

I hope that's all I need to do but my shaft is pretty chewed up and also bent so I hope it does just slide out.

[slainwarrior]

I had to to replace mine not that long ago the previous owner had bent it pretty bad from pop the chain. It had a huge arc in it but after a little wiggling it pulled right out just take your time. Pulling it out shouldnt be a problem.

[slainwarrior]

And a 4mill crank isn't a drop in upgrade because of the need for a spacer plate and porting changes but if you talk to a builder and have him setup your cylinder and tell you what spacer plate and head gasket to run you would drop the crank in with your properly setup cylinder and be good to go. Probably wouldn't cost to much to get it setup for the crank and it would be a pretty noticable difference in power.

[breastman569]

Thanks for the info. I put a call into my engine builder who ported my engine and did my head work a few years a ago so we will see what he says. Thanks again guys for the help.