Carrera 3.2 AC Compressor Too Long to Fit ITB's

[Peter M]

Actually thinking about fitting a 964 plastic intake manifold to my modified Carrera 3.2 but the inlet runner to the right rear cylinder would foul the front of the standard Denso 10P15C air conditioning compressor.

Porsche got around this by shortening the plenum on that side and putting a kink in intake runner of the standard 3.2 aluminium manifold to give the necessary clearance.

Porsche solved the conflict on later 964's and 993's by using the shorter 10PA15C compressors and using a redesigned mount that shifted the compressor rearward as well.

Has anyone faced this problem on the 3.2 and earlier cars before and solved it?

Or do all the ITB/964 plenums users just get used to not having AC?

Or use an electric compressor?

[Peter M]

This photo shows the shortened plenum to that cylinder and the "knocked knee" runner at the bottom left of the photo:

[Peter M]

Mmmm, no one?

Starting to look like my next thread search will be "Porting Carrera 3.2 Inlet Manifolds in 3 Easy Steps!"

Unfortunately no one extrude hones around here.

[stephen1070]

Might take a few days for the creative types to reply - I’d be interested in the answer too.

Are there other manifolds that are kinked ?

[Peter M]

Originally Posted by stephen1070

Are there other manifolds that are kinked ?

Stephen,

The later 964 and 993 manifolds, in fact everything else since the C3.2, appear to have nicely symmetrical runners. Here's an early 964 aluminium one. The later plastic one's have an even better reputation of providing very consistent flow across all cylinders.

[Uwon]

Don’t quite understand your issue but hopefully this will help. My 3.2 plenum from an ‘86 appears to be different than yours. It clears the A/C base bracket and Denso compressor with room to spare.





Hope this helps.
Johan

[Peter M]

Originally Posted by Uwon

Don’t quite understand your issue but hopefully this will help. My 3.2 plenum from an ‘86 appears to be different than yours.

Johan,
Like you I have a Carrera 3.2 inlet manifold with the standard Carrera 3.2 AC compressor. All fits fine.

The problem I'm trying to solve is how to fit a 964/993/GT3 inlet manifold and still keep the standard Carrera 3.2 AC compressor.

I don't think I can without retro-fitting a later AC compressor, mounts and crank pulley. That probably means changing the rear mounting consul too because I can't see how a more rearward mounted crank pulley will fit within the standard 3.2 consul.

I'm now thinking my options are:
Fit an electric compressor and then I can fit anything I want
Extrude hone the standard Carrera 3.2 manifold
Cut open the 3.2 manifold and port
Don't sweat it as it goes pretty well already with 3.4/twin plugs/993SS cams/10.3:1/Motec/AFM delete!

Thanks for your interest.

[76FJ55]

could you use a 10PA15C if you were to swap your original magnetic clutch and pulley over to it? I don't know if the mount spacing is the same as the stock 10P15C, but it may be worth a try.

Originally Posted by Uwon

Don’t quite understand your issue but hopefully this will help. My 3.2 plenum from an ‘86 appears to be different than yours. It clears the A/C base bracket and Denso compressor with room to spare.


Hope this helps.
Johan

Uwon, what compressor are you running? That is not an original 10P15C that comes stock on the 3.2. Do you possibly have a 10PA15C with the original V-belt pully from a stock compressor installed?

[patkeefe]

My compressor on my 3.0 interfered with the fuel rail on the ight side. I changed the fittings on the rail, but it still was a bit too long. I bought a Sanden SD7H13 (7312) compressor, which is a bit shorter, and fabbed new brackets from the old SC stuff. Fits OK now. A massive PITA.