924Board.org

[924RACR]

One final update on performace cooling, this for the racecar. As some of you may recall, my last race weekend was cut short by massive cooling problems. Actually, they tortured me for a while before final shutdown in the last race.

Anyway, I've been working on improving and upgrading and repairing the system to fix the problem.

In addition to replacing the stock rubber alternator bushings with metal (rubber is OK for the street, but NFG when on the track at 6000RPM), I am upsizing the radiator.

I just got the re-cored radiator back last night. I took a stock spare 924 rad to the local radiator shop, and for about $240 they cut the end tanks and mounting brackets off and stuffed a 3-row high-efficiency core in place of the stock core. We'll see how it runs, but I expect it to cool so much better!

I am also running an aftermarket plastic cooling fan, very slim, allows plenty of room for the radiator to be a little thicker... though even the 3-row is not much thicker than the original! Less than 1cm.

The thing with the alternator bracket, BTW, is because the alternator twisted so much in the rubber brackets when the alternator/waterpump belt was tensioned that it flung the belt once I revved it up to 6000rpm a few times. No surprise, but stock new rubber bushings should be fine for the street...

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Vaughan Scott
Webmeister
'79 924 #77 SCCA H Prod racecar
'82 931 Plat. Silver
#25 Hidari Firefly P2 sports prototype

[larso]

the 931 alternator seems to be much stabler, is there something in the way on the 924, you could convert it to 931 style with the 931 specific bracket that also holds air cond. (shave it for weight savings i guess).

Or is there something in the way on the 924, the intake tube, some hoses?

[924RACR]

Funny, very funny, I have the same problem on my 931, dammit!!!

It'd be illegal for ITA, though, anyway...



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Vaughan Scott
Webmeister
'79 924 #77 SCCA H Prod racecar
'82 931 Plat. Silver
#25 Hidari Firefly P2 sports prototype

[kaffine krazed]

What aftermarket fans are you using? I need to get new fans for my 944. Thanks.

[AppleBit]

I would __LOVE__ to mount my alternator or any alternator to where the 931 has theirs!!

Too much work it looks like though... you have to redo the fuel injection system cauz it's in the way...

Driving my 924 again.... What coolant issue?! I LOVE THIS COOLING SYSTEM!


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Classic British Sports Car Restoration v6 + v8 Engine Conversion Swaps

Porsche 924 Wide Body LS1 Corvette 500 Horsepower Engine

[larso]

maybe the reason 924s and 931s blow head gaskets is cause of the aluminum head on an iron block. too much difference in expansion resulting in a head gasket that can't cope with the space it has to take up and not take up so to speak?

[Blas Costagli]

You know...the other day I thru out the old fan relay I had laying atound. I replaced it years ago...the one under the dash on the fuse panel. And still being a kid at heart, I had to open it up and see what's inside. there were 2 small set screws that looked like they adjusted something internal...could they be used to set the on/off set points for the fans ????
Someone out there got time to play with it?

[AppleBit]

I still say if you have any cooling issues to go to Performance Products, spend $400 then spend $80 on a aftermarket fan (from Checker/Champion- same thing right?) and then spend $20 to have a welding shop make the brackets for the fan onto the radiator and have no more cooling issues....


PLUS! gobs more room under the hood... I have enough space to fit a small child in between my radiator and engine...

Not as if I tried it more than 3 times that is....


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Classic British Sports Car Restoration v6 + v8 Engine Conversion Swaps

Porsche 924 Wide Body LS1 Corvette 500 Horsepower Engine