3.0 to 3.2 upgrade questions

[OldTee]

My 79SC 3.0L has 146K and is beginning to show its age. I recently rebuilt a 87 Carrera and found 6 niksil in spec pistons and cylinders so I have found myself with a set of alusil P/C. The Carrera O/H was due to a broken stud.

It looks like from what I read here that this is a good upgrade and with a 964 grind and my current CIS will give some real gains.

What are the problems with this upgrade? Any mods to the case necessary? Are Carrera rods necessary?

Thanks

[Henry Schmidt]

Originally posted by OldTee
My 79SC 3.0L has 146K and is beginning to show its age. I recently rebuilt a 87 Carrera and found 6 niksil in spec pistons and cylinders so I have found myself with a set of alusil P/C. The Carrera O/H was due to a broken stud.

It looks like from what I read here that this is a good upgrade and with a 964 grind and my current CIS will give some real gains.

What are the problems with this upgrade? Any mods to the case necessary? Are Carrera rods necessary?

Thanks

Cylinders are a direct replacement.
95 mm 3.2 pistons are not a direct replacement for 3.0 pistons.
To use the 3.2 95mm pistons on a 3.0 crank you must offset the wrist pin .030 to account for the wrist pin height difference.
3.2 Carrera rods will not fit a 3.0 crank.
Reusing Alusil is always a gamble.
Good luck.

[OldTee]

How does a 3.2 get its displacment increase if the cylinders are the same? How do you make a 3.0 into a 3.2 with what I have? Sounds like I can't. Is the 3.2 P/C cylinder set I have worth anything or should I junk em?

[OldTee]

Originally posted by Henry Schmidt
Cylinders are a direct replacement.
To use the 3.2 95mm pistons on a 3.0 crank you must offset the wrist pin .030 to account for the wrist pin height difference.

How do you do this?

Thanks for your response.

[tom1394racing]

The displacement increase on the 3.2 is due to the longer stroke of the 3.2 crankshaft relative to the 3.0 crank. Pistons for both are 95mm.

Going from a 3.0SC to a 3.2 requires new, larger pistons and cylinders.

[sjf911]

Going to 3.2 with a 3.0 crank requires going to 98mm pistons (designed for a 3.0 crank) and cylinders. This gives you a 3.2 engine but with a shorter stroke than the Carrera 3.2.

[North Coast Cab]

Can you put a 3.2 crank in a 3.0 case?

[Henry Schmidt]

Originally Posted by OldTee

How do you do this?

Thanks for your response.

Send the rods to a quality machine shop.

[Henry Schmidt]

Originally Posted by North Coast Cab

Can you put a 3.2 crank in a 3.0 case?

Yes