[Fot] Nuerburgring Nordschleife 400 km race

[MadMarx]

Henry,

can you tell me the sizes of your crank and water pump pulleys?
I have the stock water pump with that sharp edged impeller. I really suspect
the impeller to cavitating when turning longer at high revs. I hold 6000 for
about 30-40 seconds in on go.

Chris

-----Ursprüngliche Nachricht-----
Von: Henry Frye [mailto:henry at henryfrye.com] 
Gesendet: Donnerstag, 2. Oktober 2008 13:55
An: MadMarx
Betreff: RE: [Fot] Nuerburgring Nordschleife 400 km race

Are you running a stock water pump with a stock pulley? If so, I find it
hard to believe it was cavitating with only 1/2 liter of water loss. 

I run the narrow belt conversion, the water pump pulley is very close to
stock, in not stock size, and run to 7000+ with a very aggressive water
pump impeller and have no cavitation issues. I have a water pressure
gauge plumbed into the block drain port at the rear of the block and it
will show over 30 pounds per square inch of pressure at max RPM.

I routinely lose about that much water every session, I believe most it
goes into the overflow. If I do not check the water until the engine is
completely cool most of it returns from the overflow bottle.

Sorry your weekend was more fuss than racing. We all have them...

> -----Original Message-----
> From: MadMarxt
> Subject: Re: [Fot] Nuerburgring Nordschleife 400 km race
> 
> 	Now the thread was burried down in the block. End of 
> race - I thought but after I told my hotelier about the 
> misfit he invented a head stud extractor while I had 
> breakfast. With that tool it took 10 minutes to get that 
> thread part out.


> 	A half a liter water was forced out - nothing else.
> 	I suppose that the water pump is spinning too fast at 
> 6000 and start cavitating which cause the water loss.
>