I have a 92 964 turbo engine that has the oil drain plug broken off of it (long story), I'm looking at putting the motor back together and was wondering if the block is interchangable with a 993 Twin Turbo block (which I've had sitting for nearly 9 years). Any ideas?

 

I want to say no. If you are using 3.3 stock parts and fitting to 3.6 block. Having the 3.6 case you can build up a nice motor for the 964.

 

hi,

the 965 3.3 crankcase is based on the 930 engine, 993 tt comes out of the 964. i dont know exact the diffrences but i assume it won´t fit.

fritz

 

DAMN! The problem I've found is that all the 3.3 cases I've found are the old style, I've yet to stumble onto a 965 block.

 

You can't have it welded.

 

Ok, I will bite. Do you have a picture? Why can't the drain plug be drilled and re welded? If you change cases you will affect the value of your car as the original case is gone.
I would think you could use the TT case and make a 3.6 turbo engine with many of your 965 engine parts. You could use your crank matched with 100mm pistons(J&E) using late model 964 or 993 cylinders and make a 3.5 or change to 964 crank and get to 3.6. Jim

 

I'll try to take a picture next week and post it.

 

Ted at German Precision told me of having to make this repair once, so you're not the first.
IMHO you can have your case welded (by someone very qualified). It'll be a conspicuous repair, but you'll have your case#. A late (non sump-screen) 930 case will work but you'll have to have the cylinder spigots machined to accept the 965 cylinder o-ring seal format. The 965 case also used 964 case bolts. The 965 case really is unique; 964 cylinder mating, but 103mm format (max 98mm bore) so you can't use 3.6 cylinders.
I'd find a 964 n/a motor, throw in 7.5 (OEM) or similar pistons, slap your CIS on it and there you have a 3.6 Turbo.

 

I think I may have a 965 case floating around the workshop, from memory it came from an accident damaged car and was replaced as the fan housing support on the rh case half had been broken off in the impact. It would be very easy to replace this part with the one welded on from your own case. So if you need a 965 case and are struggling to get a perfect one send me a pm and I'll try to dig it out and send you photos.