TheSamba.com :: View topic - cylinder wall thickness, how thin is to thin?

Sat Apr 30, 2022 4:24 pm

title pretty much says it all I guess.. how thin is to thin?
aside from just general question of interest about thickness, could thick walled 94's be cut to house 96mm pistons?

Sat Apr 30, 2022 6:38 pm

I believe that is exactly what Tabari has done, hopefully he chimes in.

Sat Apr 30, 2022 7:28 pm

IMO the cylinder should be thick as than the ring for good service life.
Most rings are D-wall
The formula for D-wall is..... Bore diameter ÷ 22 = radial thickness.

For racing......many rules are broken. So, it's not a hard rule. But it's a good rule.

Sat Apr 30, 2022 8:14 pm

Yep. Did it. For simplicity's sake, just buy JPM barrels in 96mm.

Sat Apr 30, 2022 8:26 pm

I puit about 80,000 miles on the old berg slipin 90.5's with total seal rings and no issues.( they were also pitted bad when I get them nos,( rat piss) So I torque plate honed them and put the pits upward . they worked great. I reckon if jpm makes em than it's up to your wallet and how well and how long you want them to work&last.

Sun May 01, 2022 8:39 am

bugguy1967 wrote: Yep. Did it. For simplicity's sake, just buy JPM barrels in 96mm.
i dont guess i specified which engine i was thinking i just assumed
yall'd assume i was talking about type 1 94's and not type 4. so to be clear, jpm makes 96's for type 1?

Mon May 02, 2022 10:10 am

richardcraineum wrote: bugguy1967 wrote: Yep. Did it. For simplicity's sake, just buy JPM barrels in 96mm.
i dont guess i specified which engine i was thinking i just assumed
yall'd assume i was talking about type 1 94's and not type 4. so to be clear, jpm makes 96's for type 1?

Yes. It was assumed. Type 4 96s are extremely common. JPM's 94mm barrels have an option to be bored to 96. They're extremely thick. You may be waiting awhile to get them finished, so buy them waay before you actually need them.