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jimk04 · 10-08-2014, 10:50 AM

Im doing all the homework I can into doing a 3.4 to 3.6 engine conversion.

Ive found the Wossner pistons and they list all the speca of them (OE specs)

As you are probably aware, to go to 3.6 from 3.4 requires 99mm bore. The 997 3.8 has a 99mm bore.

Can we use these off the shelf pistons for our 3.6 big bore engines?

3.4 996 spec

11.3:1 CR
15cc bowl in top of piston
32.3mm compression height.

3.8 997 99mm pistons

11.8 CR
13.8cc bowl
33mm compression height

out of interest

3.4 987 S
7.8cc bowl
11.1 CR
32.3mm compression height.

Does the 3.4 996 engine , albeit with a 99mm bore, accept thr 997 S pistons?

10-08-2014, 10:50 AM	#1
jimk04 Registered User Join Date: Sep 2013 Location: uk, notts Posts: 141	3.4 to 3.6 using 997 3.8 99mm pistons Im doing all the homework I can into doing a 3.4 to 3.6 engine conversion. Ive found the Wossner pistons and they list all the speca of them (OE specs) As you are probably aware, to go to 3.6 from 3.4 requires 99mm bore. The 997 3.8 has a 99mm bore. Can we use these off the shelf pistons for our 3.6 big bore engines? 3.4 996 spec 11.3:1 CR 15cc bowl in top of piston 32.3mm compression height. 3.8 997 99mm pistons 11.8 CR 13.8cc bowl 33mm compression height out of interest 3.4 987 S 7.8cc bowl 11.1 CR 32.3mm compression height. Does the 3.4 996 engine , albeit with a 99mm bore, accept thr 997 S pistons?