ditto

It works downslope and on the level, but not on much of an incline. At some point I have to clutch out to prevent stalling whereupon gravity takes over.

Amille28

Thanks to all who contributed to helping me make my decision. I'm price comparing engines right now but I think I will end up going with the used 3.2 if I can find one at a good price. I guess the only way to tell if this will work and do some mythbusting is to actually try it. I spent a considerable amount of time reading the boxster forum on the 3.4 to 3.2 swap. One of the big problems is with their intake setup but I plan on using the 996 manifold so I think the swap from boxster to carrera might be easier than the other way around.

alpine003

Just curious and why not go the other way and get a used 3.6 bottom end with the 3.4 top? I would rather do that than mess around using a 3.2 for awhile if you're gonna go through all that hassle. Just my $.02

Amille28

I think what you are trying to say is why not use a 3.6 bearing carrier and crank assembly in the 3.4 engine case?. The stroke on the 3.6 bearing carrier crank and rods is longer and would cause the pistons to hit the valves and bend them.

The bearing carrier in the boxster 3.2 and carrera 3.4 are the same, they also share the same heads. The only difference is the engine case, which is the same casting, but the 3.2 has smaller diameter pistons. I think 92mm vs 94mm but im not 100% sure on those sizes.

The short answer to why not is cost... i plan on just dropping in a used 3.2 long block engine without tearing it apart for a rebuild.. I dont have many of the special tools required for rebuild.. and its about 2K to replace everything that would really need replaced to do a proper rebuild. Head gaskets, piston rings, carrier and rod bearings, seals, gaskets, chains, chain follower, machine work.. and while your at it why not put some of LN's billet stuff in there, forged rods, ARP bolts, $$$$$$$$$$$$

Imo000

I think what he is saying is to use a 3.6 shortblock and bolt on the 3.4 heads and intake.

alpine003

Bingo
Take this opportunity to "upgrade" instead of just repair...

Amille28

Has this been done? My understanding is that 3.4 heads won't work on a 3.6 case. (unless you have a 3.6 LN engineering Nikisil case). Please correct me if I'm wrong. It will make me happy.

alpine003

There's at least a couple that has done this including one member here on this forum. IIRC, he didn't even have to reprogram his ecu.

I hate to say it but do a search and you will be able to find him and maybe message him on certain details.

Imo000

Amille......there is no case on these engines, its actually a more or less a standard engine block. The cylinders and the bottom end are one. Two halves for each bank but the cylinders are non removable.

TomF

This is looking like a "downgrade" rather than an upgrade. Not to rain on your parade, but anytime you change the standard configuration on a Porsche you are going to incur significant costs in $$$ or time. A change in engine type is not going to solve your resource issues.

Don't chase the rabbit down the hole...there are lots of really knowledgeable people here who are saying this is a false economy.

Cheers,
TomF

Amille28

Well I am engaged at warp speed down the rabbit hole. I'm about halfway complete with this swap. We will see how it goes.

At no point did I say I was desiring an upgrade or wanted to increase performance of the car in any way. I am curious to see if I will even notice the difference.

lee101315

We just had this conversation on the 986 forum http://986forum.com/forums/performan...boxster-s.html

If you swap your intake and exhaust manifolds onto the 3.2, you'll only be down about 15-20 hp, not 46. Porsche killed the 3.2s performance by restricting it's breathing.

Amille28

Thanks for the link. I agree with the posts that much of the difference between 3.2 and 3.4 engine's performance variation is intake/exhaust related. If anyone is curious within a week we will have hopefully an example to dyno.

I must say the engines are extremely similar on the outside. I did have to drill and tap holes for the 996 exhaust hangars and the intake manifold. I purchased a long block so I am still in the process of swapping everything over. When finished I will have a stock 01 996 everything with a 00 boxster S 3.2 engine.

I'm thinking some simple mods such as high flow cats, IPD intake plenum, and possible 3.8 exhaust manifolds might net the difference 0.2L

There are many people that in the Chevy LS world substitute a 5.3 engine vs the LS1 5.7. A set of decked heads, Z06 cam will give very similar performance in a vortech 5.3 with a 5.7 LS1.

My car is a daily driver and I love driving it every day. My bet is that my tired 153k mi 3.4 was probably out the 20hp anyways from being old.

Imo000

Ecellent! Document everything and post it for future reference.

Amille28

here is the 3.2 posing as a 3.4

Install is finished with 150mi on the 3.2. Runs and drives great. The swap was not overly difficult. Everything from the 996 engine exterior was used on the 3.2 longblock.

Performance feel is crisp and very drivable. It is hard for me to make an apples to apples comparison. The newly installed 3.2 has a brand new clutch and excellent throttle response.