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Horizonblue · Posted: Wed Apr 18, 2012 6:17 am Post subject: Alternator relocation

I'm in the middle of an engine project(N/A) and considering moving the alternator to the Turbo location. The original placement of the alternator has it's downsides; exposed to heat from the manifold and quite hard to get to.

What do you think? Is it worth the effort? I will probably make the brackets myself.

I have prepared a 931 S2 intake manifold for the N/A head, so there should be enough space for the alternator.

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Euro 924, 1976

"If you can't fix it, don't break it"

/P.G. Andersen

ideola · Joined: 01 Oct 2004 Posts: 15550 Location: Spring Lake MI

If you're converting to EFI in the process, it should be a no-brainer. Just be aware that the pulley arrangement may need to be investigated a little...there were at least three different versions of the crank pulley that I know of, and the water pump pulley may need to be reversed and/or mounted with or without the ~2mm spacer in order to get everything to align correctly. Why wouldn't you just pick up a second hand 931 alternator mount? Seems like that would be much easier than fabricating your own brackets.
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erstwhile owner of just about every 924 variant ever made

Horizonblue · Posted: Wed Apr 18, 2012 7:45 am Post subject:

ideola · Joined: 01 Oct 2004 Posts: 15550 Location: Spring Lake MI

The 931 bracket should not be hard to find nor expensive. Maybe on that side of the pond, but here they are plentiful. The big rubber bushing on the left side in that photo is where the AC compressor mounts, just like on the NA version of the same bracket.

As for the pulley stuff, it's not as big of a deal as you make out. On the NA, the water pump pulley has the deep side facing the windshield in order to align with the alternator. The alt+water pump belt rides in the middle groove on the crank pulley, with the A/C belt on the outer groove. Here's an NA setup:

On the 931, the water pump pulley has the deep side facing the front of the car, and the alt+water pump pulley riding on the outermost groove of the crank pulley. The A/C belt then rides on the middle groove. Here's a 931 setup:

This is true for US cars, as well as the ROW 931 and 937 that I have, but I'm not 100% certain that there may be other iterations, especially for ROW NAs as I've never taken one of those apart

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erstwhile owner of just about every 924 variant ever made

Jakkq · Joined: 29 Sep 2008 Posts: 810 Location: Omaha, Nebraska

An Alternator relocation would be just awesome. I hate working in that area.

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1979 Porsche 924- Snailshell
http://porsche924workblog.blogspot.com/