Hey fellas,

I have a 91 964 and a 70 911 and am not a wrench...

Has anyone tried this swap? I've seen 993 tt motors in 964s and 965 motors in older 911s and i'm sure it's a lot of trouble.

Would the 965 motor fit? Any suggestions on the Transmission ie: stronger clutch etc?

Thanks for the comments..

 

Should be an easy swap if you have the wiring harnesses and control units. The only physical issue is fitting the intercooler. You will need some type of wing to fit it.

The G50/52 came with the turbo but there are quite a few versions that will bolt up.

Definitely want LSD if the car is not already equipped.

 

well now that is a good reason to get the big whale tail. any idea what they go for these days and do you buy aftermarket or original equipment.

the motor comes will all wiring but no a/c compressor which i have. Does the A/C system also tie in the same? It looks the same from the pictures.

I think i have the G50 transmission and will be replacing the clutch. Any suggestions on which one that would be apply to daily driver duties? I am stuck in traffic about 2-3 times / week for about an hour or so. Otherwise mostly open road (local and highway) motoring....

 

Oh, quick question to the gang.

A 965 motor with 58K miles on it. Any major concerns that i should be aware of? I suspect that it all depends on the nut behind the wheel and regular maintenance items.

Anything that stands out / fails from age and little use? 58K miles in 17 years usually means it's been sitting alot... looking at motor from dismantler so i don't expect much in the way of history on this car.

 

Compression test it. Change the turbo to a modern one. Warm up reg always go, but they can be fitted with engine in.

 

Compression test isn't going to tell you as much if you have a broken ring, head stud, worn valve guides. Leak down can give you a better idea as to what's going on (where the air is leaking for instance).

The stock K27 is a decent turbo. If it's fine I would argue it's not worth the $'s for the supposed performance gain you get (or loose) over the bigger turbo's.

The WUR on these cars are perfectly fine. We like to speak here about the Leask adjustable WUR. However for these newer turbo's our WUR has a bit more to it...just open it up and you'll see what I mean. If it's working these will serve their purpose.

What to look for on an uknown (turbo) 91 motor? Broken rings from two much boost or head studs from corrosion is a good start....

 

To be honest if you have a solid 964 I would recommend turbocharging the N/A motor instead of modifying teh car to accommodate a 965 motor.

You can easily get an additional 100 rwhp out of a 964 engine by turboing it and if you use the right chips etc you can get 250+ rwhp out of a sound 964 engine. so you could see as much as 350 rwhp with a n/a engine turbocharged and have a more practical car for far less $$.

 

Thanks for the input.

I'll get the leakdown numbers before buying for sure.

What is the warm up reg and, dare i ask, are they expensive? do we have these on 964s?

Broken rings: do you mean piston rings? Would be very smoky on startup... any other telltale signs? lack of power?

Car is from Texas so i would hope corrosion would be minimal. Not much salt being used in the winters there. Lots of Salt Water though!!

Cobalt: i would agree with you about the turbo 3.6 vs turbo 3.3 with the extra displacement. What do you figure the stock 3.3 has at the wheels? 350 rwhp would be incredible... 430 hp? priceless. What do you estimate are the torque figures?

What about the costs: i need to rebuild my 964 motor with 293000kms on it so it would need to be beefed up and what would it cost to add the turbo and related bits?

 

The 3.3 and 3.6 964 turbos both used the antiquated CIS or K-jetronic injection system. Not an issue until they become an issue. I have owned several cars with the CIS system and have had no issues with any of them. My father has a 75 450sl MB using CIS and he has never had an issue since 1975. Some people I know have had nothing but problems and when CIS screws up it can be a real PITA. Since you have a 3.6 Motronic to start with I would get some local shops to quote you repairs on it and see what you are at. Another nice upgrade for these motors but expensive is a 3.8l set of P&C's. Adds lots of low end torque.

I wouldn't guess to say what it would cost since anything could need replacing with a higher mileage engine. Although I have seen some nice clean strong engines with high miles.

 

I assumed you'd do compression and leak down at same time, and agree you should do both.

 

Leak down, compression and pull the valve covers and look for broken head studs...Often overlooked.

 

A new WUR for the 965 is very expensive new (if you can find one). Over $1k. The 964 3.6 na doesn't have one.

Yes piston rings. No....you won't necissarily get smoke at start up or have a noticable loss of power. Leak down is a very good way to detect this.

 

I will have a full efi 3.4 twin plug forsale soon. 600+ JUDD BHP....

 

Alex, did you get the 965 motor? If not what condition and location?
I am currently seeking a '91-'94 turbo engine,found one in cali with
similar mileage...any help? Thanks Bert

 

As stated, your car currently has 3.6 & EFI, converting back to 3.3 & CIS doesn't seem a good idea when all you need to do is change some exhaust, add a turbo, an intercooler, custom piping and an adjustable fuel regulator. You could even lower the CR when you rebuild your engine if you wanted to.
You'll also need two fuel pumps for CIS when you car probably only has one pump.