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ideola · Joined: 01 Oct 2004 Posts: 15548 Location: Spring Lake MI

I've been doing some analysis of my project budget based on what I have already spent + what I plan to spend to complete the project. Here is an interesting result.

~40% of the budget is earmarked for drive train development (i.e. head, block, turbo, cooling, engine management, and transaxle)
~20% of the budget is earmarked for suspension and brakes
~40% of the budget is earmarked for body, chassis & electrical

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erstwhile owner of just about every 924 variant ever made

gegge · Joined: 27 Jul 2007 Posts: 1124 Location: Sweden

I would like to ask why you have ruled out knife-edging and further lightening of the crank in your ultimate-build 924?

Not for comfort or streetability I guess..?
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Carl Fredrik Torkildsen

924 turbo -81 Carrera GT RESTOMOD
924 turbo -80 Dolomite De Luxe
924 -85 DP kit, BBS RS, M030 and tuned engine
924s -86 Black on black turbo with Fuchs

Scorpio · Posted: Wed May 20, 2009 8:27 pm Post subject:

ideola · Joined: 01 Oct 2004 Posts: 15548 Location: Spring Lake MI

ideola · Joined: 01 Oct 2004 Posts: 15548 Location: Spring Lake MI

Some of the last major pieces to the puzzle are falling into place now:

Pace Products Dry Sump system is on order, ETA is unknown
The Davies Craig cooling system components are on order and should arrive within days (EWP115, EBP for the turbo, and 12" thermatic fan)
Complete Tilton 3-pedal assembly, along with master cylinders, remote bias adjuster, and 3-chamber reservoir are on order
Elephant Racing geometry correcting tie rod kit is on order
The rest of the suspension bushings, along with the rotors and pads are on order
I've found a very nice, compact 160A alternator for use with my planned axle-driven setup that is on order and should arrive any day now. Photos and source to follow soon.
I've also found a lightweight gear reduction starter for the 944 that will work for this application, should be on order this week

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erstwhile owner of just about every 924 variant ever made

Scorpio · Posted: Thu May 21, 2009 8:52 am Post subject:

160 Amp alternator ? you taking your UWB car to a sound off hey?

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1979 NA
MS1..EFI..
GARRETT T25 TURBO
BILSTEIN SHOCKS
GT BASED CUSTOM BODYKIT

Brisbane , Australia
Think mean think fast
all youll see is
my Porsches Arse!!!

ideola · Joined: 01 Oct 2004 Posts: 15548 Location: Spring Lake MI

FSMITH010 · Joined: 24 Apr 2009 Posts: 101 Location: Los Angeles, CA

100% = ?

ideola · Joined: 01 Oct 2004 Posts: 15548 Location: Spring Lake MI

peterld · Posted: Thu May 21, 2009 12:25 pm Post subject:

But don't ever let the missus see it!!!

FSMITH010 · Joined: 24 Apr 2009 Posts: 101 Location: Los Angeles, CA

bass gt · Posted: Thu May 21, 2009 4:35 pm Post subject:

Dan,

Well done on going the Dry Sump route. If you need any pointers, or have questions, you know my mail addy.

Steve
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Front Wheel Drive is the Devil's work.

john h · Posted: Thu May 21, 2009 8:36 pm Post subject:

Dan,

I'm interested in how you are going to keep the alternator from overspeeding when you're running it off the axle.
My calculations (which couldbe wrong) showed that at 160kpm (which I get to at some circuits) the alternator would be turning over at 30,000 which is about 12,000 more than Bosch suggest. That was majorily under driving the alternator.
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Remember a Porsche is not just for Christmas,

if you take it to pieces slowly it can provide anguish all year long!

ideola · Joined: 01 Oct 2004 Posts: 15548 Location: Spring Lake MI

John, that's a good question, and truthfully, I haven't really thought that far ahead. Most of my track time will be at Waterford Hills, so getting up to 100MPH / 160 KPH probably won't happen often or for extended periods.

I'll contact the supplier of the alternator and find out what their recommendation is. To an extent, I think some of the issues could be solved with a larger pulley on the alt itself. I really don't want to have to get into a clutched pulley, but I'll go down that path if I have to.

I wish we had more details on Frank's D-Prod setup.
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erstwhile owner of just about every 924 variant ever made

ideola · Joined: 01 Oct 2004 Posts: 15548 Location: Spring Lake MI

Also, I should mention that I'm not going to be using a Bosch unit. The supplier I contacted recommended a modified high-output version Delco CS130D. Unlike the CS144 discussed elsewhere here, the CS130D has ball bearings rather than needle bearings, which according to my supplier makes it more durable and resistant to the abuse it will be subjected to in the rear of the car.

I explained my application in detail, including the rear-transaxle mounting and projected size of my custom drive pulley, and the CS130D was his top recommendation. Bear in mind, because my setup is completely custom, I wasn't constrained to any particular configuration. The CS130D is a very small and compact package. As a second option, they also mentioned the AD244, which is a large case version of the CS130.

In any event, I'll do some investigation regarding acceptable RPM range. The good thing is that I have not yet made my pulley. With the piece of raw aluminum I have, I can go anywhere from ~7" to ~4" depending on what we conclude is suitable for the alternator.
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erstwhile owner of just about every 924 variant ever made