Does anyone know what needs to be done to properly fit an early 951 oil cooler console with casting number 0R onto a late 87 block that uses the late 1 piece OPRV?

The late 951 oil cooler consoles have a casting number of 2R and 3R, which I think also had one or two other changes to the console casting along with the change to the 1 piece OPRV.

The early 951 console with casting number 0R still used the old 3 piece OPRV and had a removable sleeve which the OPRV passed through.

So far all Ive found is maybe use an additional spacer, and possibly machine the first few threads off the late style OPRV to get it to thread in all the way, but none of this is confirmed.

I know a lot of guys dont have an OPRV alignment tool because they can be expensive. I just found a hard plastic economy version on ebay for $16. There is a version for both early and late.

Early

www.ebay.com/itm/Porsche-944-951-1982-86...ne-New-/112022671926

Late

www.ebay.com/itm/Porsche-924-944-951-968...ne-New-/111979928561

I'm late, did you get it figured out?

I have a turbo housing on my car, not sure the casting #. But I'm using the 1 piece OPRV without modification.

See the OPRV TSB in this thread (if you havent already), could be of some assistance.

forums.pelicanparts.com/porsche-924-944-...f-valve-o-rings.html

Manuel_M wrote:


Havent gotten it figured out yet but I found a late casting 951 console which matches the 87 block Im installing it on.

Im wondering what dictates the use of the early or late OPRV? Are you using the early or late 1 piece on a late block?

Had to dig deep in my build pictures lol. Im using the early 1 peice (figure A in TSB), an 86 block and not sure which model of the turbo housing.

Based on how Im reading the TSB, both 1 peice OPRVs should be compatible with all 944 engines.

Note: the first 2 times (45 mins total) I ran my new engine the OP was pegged. I guess the valve became unstuck on the 3rd startup.