I thought about that, it's why I think it will take some testing. I suspect
that at higher RPM the pump isn't increasing pressure linearly, there's such
a big range of RPM that it operates over. There's a good chance the block
pressure wouldn't change. The easy way to find out would be to put a gauge
on the block and try it. None of the things we're doing are particularly
scientific, so I bet there's a lot of optimization room. If you decreased
the crank pulley size you might be able to increase the orifice size and
have the same flow and pressure for less horsepower. My water orifice is the
size of a dime, at high flow that's doing a lot more to drop downstream
pressure than changing the pulley size would.
-----Original Message-----
From: owner-fot@autox.team.net [mailto:owner-fot@autox.team.net] On Behalf
Of Henry Frye
Sent: Saturday, March 26, 2005 3:55 AM
To: fot@autox.team.net
Subject: Re: FOT Project Pulley
At 07:45 PM 03/25/2005 -0800, Bill Babcock wrote:
> It would be a very worthwhile endeavor to get a smaller crankshaft
>pulley or a larger waterpump pulley. We probably need about 60-70
>percent of the pump speed we have now. It would require some testing
>and some engineering, but it seems like a worth project. Ken--have you
>ever considered doing something to fiddle with the pulley ratios?
Remember, slowing down the water pump will further reduce the coolant
pressure in the block. You want decent coolant pressure in the block to
quench the steam bubbles that will form, and the inherent poor coolant flow
towards the rear of the block makes #4 the target for localized overheating.
I'd be cautious with this approach to finding more ponies, especially if you
have had cylinder #4 overheating issues.
|