Piston clearance

[sean_V8_914]

what is typical for piston to cylinder clearances in an air cooled T-4?
if the piston measures 94mm, what should the bore measure?

[Alfred1]

For the 2.0L motor, the 914 Technical Specifications booklet says that the cylinder/piston play for new parts is 0.02 - 0.05 and 0.20 for wear limits (I believe those are mm values).

For 96 mm, KB hypereutectic pistons, Jake likes ".002 measured @ .500 above the skirt" (values in inches, I believe).

[sean_V8_914]

thanks! That is similar to what I would expect when building a Chevy. I thought an air cooled engine might want more clearance

[cnavarro]

With forged piston, yes, they need more clearance, like ".0035. Keith Black's don't expand, so you can run them tighter. Though for comparison, we've run our Nickies as tight as ".0015 w/ JEs, since they expand at the same rate.

Charles Navarro
LN Engineering
http://www.LNengineering.com
Aircooled Precision Performance