stroker engien bore question. Thanks!

[scottsee]

this "is" a double post, it was posted elsewhere on a diffrent fourm, a Low traffic fourm. sorry. im hopeing somone here might give me some insite! Thanks. scott.

i have a question. im bulding a 6 bolt 4g63 2.3 stroker. i've been asking alot of questions on my native AF.com. i've been strugling with the question, "do i take a chance and bore (.008) my cyinders to 87.0/3.425 and use the K571M87 kit with xx rings to provide larger displacement? or go smaller like (.006) 86.5/3.406 kit #K571M865? i've noticed weisco is one of the only piston companys that have a stroker 21 pin kit for 4g63 100mm stroke @ .008 over. there must be a reasion, but i cant seem to find anyone who's done it, or who can answer my question. "is .008 just unreliable"

 

[huafist]

When you bore out that much, you've reduced the walls between the cylinders so much that heatsoaking the metal between them can possibly occur. As I'm sure you're aware, overheating a block is a bad thing. 86.5mm is fine, 87mm IMHO is too much. I'd rather play it safe than sorry, and .5mm isn't going to get you THAT much more displacement (2353cc vs 2380cc). Honestly, I'd go to 86mm and leave it at that. The displacement is going to be quite similar (2326cc). You're not really going to lose anything, and if something happens down the road (God forbid), you have room to bore your block and re-use it.

 

[scottsee]

that the problem i keep thinking about. using weisco 2618 336g pistons & xx rings, they will expand ever so slightly more then the weisco alluminum forged pistons. i'll be boosting 25+ and shooting nitrous, so it might be a good ideah to leave at least one more bore avalibile if stronger rod angles durring a race happen to throw an expanded piston into the cyinder walls, blow a ring, whatever. id better just go with .04 over just incase.

 

[peregrine]

wiseco has had a *couple* of problems with the skirts cracking in high boost+nitrous situations. i think they are working on a fix but you might want to email them.