pete-r

Hi,

I have been reading this forum quite a while now but this is my first post. I tried to search the answer to my question but didn't really find anything. Maybe I just had the wrong keywords or something

So how hard would it be to swap the water cooled 996tt engine in a 964t? What would be the main problems in this kind of project? Which transmission should be used etc. ? If there's already a thread about this maybe someone can point me in the right direction. I also tried to search using google but I didn't find anything related to this kind of project. Has this been done before?

From what I understand there are a lot of people who think the air cooled engines are somewhat legendary and shouldn't be swapped to those more modern porsche engines but don't worry - I'm not about to buy a porsche. I'm just interested in general. I have also noticed that the 996tt engines are actually cheaper than the air cooled (993) twin turbo engine. And correct me if I'm wrong but the 996tt engine should respond a bit better to power upgrades and is stronger.

Thank you in advance. Nice forum btw.

-Peter

pcar964

I'm not sure if it would fit, but even if it did it would be a hell of a lot of work to run the additional plumbing for the radiators alone. Wiring harness would be a headache because the new cars have e-gas (I think). The engine block is essentially the same between the two, but that's about it.

The biggest question one would have to ask is: why? A person would be better off spending the money to convert the 964T engine to EFI and then you have all the HP you want.

pete-r

Thanks for your reply. So the 996tt engine is not better/stronger then? I would think there might be some overheating problems in those air/oil cooled engines? Also if one has the 3.3l engine he would get a bit more diplacement with the 996tt swap.

Not sure if these are good enough reasons though. Maybe this kind of swap would be better suited for those NA models? What does people usually do when they want more power from their NA 964 or 993? Do they just go and buy the turbo version because those older turbo engines seem to be quite expensive.

Thanks

-Peter

kleinbbc2

There is a post with this done not sure were. They vented the hood for the radiators not sure about the gas pedal.

JamesE

I will have a 965 3.4 ltr twin plug for sale soon. Built by CTR Developments and JUDD. Only has about 3k miles on it.

LA964RS

Issues.....Intercoolers.....as they require air flow to work. You can run a top motor cooler like Gemballa does for the "after cooler" set up they do for the Avalanche (puke!), but it won't get airflow as there's no fan pulling air into the engine compartment so it'll heat soak and be worthless....air/water set ups are real questionable and when I was looking at air/water systems, no one could give me any data on if they really worked.

But if you're serious call Turbo Kraft in AZ, they'll have an opinion on it all.

Otherwise, the plumbing for the rads is not a big issue and they'll fit in the front trunk.

pete-r

Thanks for the information guys. Clearly the intercoolers might be a problem. Of course one could make an air intake for the top mounted IC but that would probably be quite ugly.

This might be a stupid question but the 964turbo doesn't have an IC as standard, right?

-Peter

mishpet

hi james can you send me the spec on your judd engine.
regards pete

pcar964

pete-r, sounds like you need to do some research on 911 turbos. You have much to learn

tjr

All 911 turbos, with the exception of the original 3 litre 930, have intercoolers. Here's mine:

pete-r

Yeah that's probably true. I don't know much about porsches in general either but I'm quite interested since those techart and evoms 996tt's seem to beat my japanese "muscle car" from time to time. There are a couple of fast 997 turbo's also.

Haven't seen any fast older porsches here in Finland but I'm sure there are a few. I just think the older porsches look better than the newer ones so that's why I thought it would be nice to see one with a modern porsche engine. But I guess there are plenty of good reasons not to do this kind of engine swap.

-Peter

tjr

The newer 911 turbos are faster and more refined, the older ones slower but more charismatic, especially in the looks department. By taking the 996TT engine and putting it into a 964 turbo you are taking away some of the charisma and in most people's eyes, devaluing the car.

The simpler solution to make a 964 turbo faster without damaging the value and ruining the character, is to tune the existing air cooled engine. There are many people on here who have gone down this route - myself included. The costs vary considerably of course - from people like me doing some simple bolt-ons to JamesE above who has gone down an altogether "different" route!

Good luck with whatever you decide.

cobalt

Fast in what way? You can go EFI and get as much HP as you like out of a 3.3 or 3.6T handling is another issue. These are older cars and require some serious modifications to keep up with the newer cars especially heavily modified newer cars. It can be done but at what cost and then what are you achieving. If you want a fast car with modern handling and abilities with the least expense buy a used 996TT and put little into it. It will cost you far less than trying to shoehorn a 996TT engine into a 965.

BTW the 965, 993TT & 996TT all use the same castings for the engine. Internals vary but generally they are similar and if you plan on going above 600 hp should consider replacing and modifying most internal parts with stronger much more expensive components.

pete-r

I meant fast street cars so mainly straight line performance. I don't take my car to the track that often.

I suppose it wouldn't make any sence swapping the 964t engine for a 996tt engine. Sadly the 996tt's are very expensive here in Finland because of the car tax. With 964t and 996tt the tax system is based on power to weight ratio which makes the powerful 996tt much more expensive. I'd say the overall price of 964t would be around $50k here and a decent 996tt will be at least $110k.

-peter

cobalt

I see your point. Here a nice 964 turbo will run you around $50-$80k and a nice 996TT will cost $45-$65K for comparable condition and mileage.