s50 Pistons and Rods

[devonjordan]

Are they good for anything other than putting in an M/S50? Stroker type stuff for e30's?

I did a search, but didnt come up with much.


Thanks
Devon

[SpecM]

pistons are no good for m20s

but the rods are ok... the same length (135mm), just lighter, iirc.

[devonjordan]

Cool, so rods to save if I ever get back into an e30 then. What about M42, I know this is in M20 land, but I'm curious.

[SpecM]

What about M42

I don't think so

[Hick]

s50 pistons and rods plus M44 crank makes 2.0L M42's

[SpecM]

s50 pistons and rods plus M44 crank makes 2.0L M42's

did not know

some boring required, im sure, as m42b18s have the same 84mm bore as an m20b25 (s50b30 bore is 86mm)
so I'm assuming that the m42 block is cast-iron. I thought it was cast from Alum? Maybe not...

but... I've heard/read that m44 cranks are not as well balanced as an m42 crank... is it true?

[devonjordan]

Hmmmm... 2 liters you say?

[nando]

M42 block is cast iron

you probably could use the S50 pistons in an M20, but the bowl shape & squish area won't be right. it'd be great for an M42 though. The rods you can use in pretty much anything (m20, M50, M42, etc).

[rThor432]

but... I've heard/read that m44 cranks are not as well balanced as an m42 crank... is it true?

Not sure about balance, but iirc the M42 crank is forged and the M44 crank is cast.

A customer's S50 blew up 2 pistons when he over-revved it drifting (stupid kid...). The remaining 4 pistons look to be in good shape and the rods may be usable as well. I'm thinking about trying these in an M42 with some hotter cams. I like that little motor, but it just makes shit for power..

[Knockenwelle]

The M50 rods are lighter than the same-length M20 rods because they've had material removed from the top of the big end, and from unter the pin. Read: thinner beam, thinner web. I built my M20 with M20 rods. Unless you're really twisting that baby, I prefer more meat where it counts. Unless of course we're talking Oliver, Carillo, or other comparable billet goodness...

[nando]

ehh, in the power band the M20 is capable of (sub-7000rpm usually), M50/S50 rods are plenty strong enough. I'll take less weight, thanks.

[SpecM]

ehh, in the power band the M20 is capable of (sub-7000rpm usually), M50/S50 rods are plenty strong enough. I'll take less weight, thanks.

agreed

s50 makes more power than an m20 anyway, why wouldn't it be strong enough?

[Knockenwelle]

Revs break rods, not horsepower.

[nando]

Revs break rods, not horsepower.

uh, okay. isn't that what I said? you aren't going to be reving your M20 much past 7000rpm. S50 rods are more than capable of handling that.