Paul Dortkamp

Race cars develop a lot of heat in the engine bay and mine is no different. One recurring issue for me is that the stock alternator position is near the headers, behind the power steering pump and just in front of the oil cooler lines. The Bosch unit I am running did not have room for an air duct to fit by all the other plumbing.

Solution became apparent when studying the engine bay: Clutter on the LHS, empty space on the RHS. My race car is kept at a mechanical workshop so it was straightforward to ask for some brackets to be made up which used all those handy holes left over from the aircon and airpump.

Brackets and fitting was done by the shop and modifications to the wiring by me.

The unit was tried out on Friday and all worked fine. Still up on stands for some tidying up but looking forward to seeing how it goes on the track.

Also took the opportunity to move the power steering pump slightly to give a little more clearance.

Opelotus

Awesome! I was just thinking about this the other day. I have no AC or air pump so that leaves plenty of room on the right side of the engine to maybe fit a different/larger alternator. Those brackets look really nice too.

STRIKEMASTER

Really cool mod! I have an '83 euroS with no air pump or other Environmental Perfection Junk on it. I'd really love to get my alternator up higher so I don't have to worry so much about high manhole covers etc. Were the brackets pricey to have made? If they aren't "Typical Porsche Prices" I'd be interested in getting a set for my Shark.

FredR

A interesting modification-

Just an observation though- having conversed with many of the 928 racers never heard of and/or read about anyone actually implementing such a mod previously logical as it may be.

Just makes me wonder why you felt the "localised heat" would cause a problem for your alternator such that it needs a solution given cooler air is ducted in there. I cannot imnagine it is a weight reduction measure type of thing.

Neat install nonetheless and good luck with it.

Regards

Fred

Paul Dortkamp

Hi Fred, main issue to me was that the voltage regulator was almost touching the braided oil lines from the block to the oil cooler. My view was that the extra heat load from the oil lines was too much for the alternator. I could not see how to get any cooling air to the back of the alternator with plumbing in the way. The heat soak was shutting the alternator output down.

I will be at the track this weekend for an inter-club challenge, so i will see if any benefit has been gained. I have not run a cooling duct to the rear of the RHS alternator yet, waiting to see how it goes.

FredR

Paul,

Good luck- hope it works for you-no better way to find the limits of what works [and what does not] than at the track.

Regard

Fred

Paul Dortkamp

The track outing on the weekend was successful. Alternator output was maintained over the day in the 14V + range. Local temperature on the day was 20 - 25 degrees C, so not stressful and the format was super-sprint of 5 lots of 4 -5 laps of 4kms.
The previous time on the shorter track, the alternator stopped charging by the end of the day and I had to miss the final session and put it on the battery charger and let everything cool down before I could go home.