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chesterak
21-10-03, 08:31 PM
Anyone know the flow rate out of these pumps. For example, flow rate at 'x' rpm in litres/sec or minute and/or flow rate at 'y' psi discharge pressure.
I need this info to calculate frictional losses around an oil cooler system where an engine has failed (sized No. 6 big end - twice!).
Are the pressure relief valves adjustable?
RusselRam - I sent you a direct e-mail after talking with Ian Richardson, not sure if you recieved it.
Thanks.
Stan
:} :} :}

kev
21-10-03, 09:34 PM
Is this the Wildcat engine that failed on the Dyno in North Wales?
If so will you post some more detail, my Wildcat engine is nearing completion and I would like to know what has happened to your engine. I spoke to Ian about this and he seemed to think it may have been due to foreign matter in the bottom end.
FYI I had to return my crank (4.6 stoked to 4.8) as they had failed to properly machine the journal for #8 big end. x(
regards
Kev

chesterak
22-10-03, 12:32 PM
No, this is nothing to do with any dyno engine failure. This is to do with two different 5.0L engines (one TVR bottom end) failing in competition. The common factor to both is the installation and oil cooling systems. I want to calculate frictional losses in the oil lines to/from the cooler so I need to know the flow rate at a given rpm or at a given pump discharge pressure or, preferably, both.
As a matter of interest, I'm building a 5.0L Wildcat myself, but with V8Development heads.
Stan
:tu

russell_ram
22-10-03, 08:52 PM
Stan,

Sorry chap but have done some checking today and can't find a flow rate spec on any of the front cover drgs. For your calcs you could try pumping a pint of oil through it by rotating the crank and counting the number of turns it takes. This would give you an approx rate for any given rpm (without taking higher speed pumping losses into account) - it would be as good as a guess from me.

Alternatively try phoning Hobourn-Eaton.

I would think that 1/2 bore pipe is much too small for what you are trying to do - personally I would be thinking about 5/8 or even 3/4 inch pipework.

My 5.2 Wildcat still in bits I'm afraid.

Russ

chesterak
23-10-03, 01:31 PM
Russ,
Thanks for the reply....All I'm trying to do is prove to a mate of my Sons why his engines may be failing. I have some dry sump data that indicates 30-35 l/min so I've used that. I recon that at full chat with 1/2" hydraulic hose and fittings (which are reduced bore) a system with rear engine and front oil cooler (2 metres supply and return), ignoring loss across filter and cooler, it will lose about 24psi. This means that (as I would imagine the relief valve will be open) the pressue available to the engine will be somewhat less than 50 psi - to be certain, it could be measured - which is not good news for a 350+ bhp monster. Common sense indicates that 1/2" is too small - I have very short lines in my Cob build and they are 5/8"! - to me the moral of the story is don't just assume the "expert" who you buy a completed vehicle from has got everything right.
Stan
:tu

russell_ram
23-10-03, 01:49 PM
Stan,

As you say, the obvious thing to do is to measure the pressure on the return from the cooler where it re-connects to the front cover. As you say pump pressure is limited by the relief valve on the pump output - nearly always open at anything more than idle speed - and will be caused to open in his case by the prssure head in the pipes. This, of course, bares no relation to the pressure after the hoses. He should learn that pressure and flow are totally different animals ! ! and in an engine flow is as, if not more important than, pressure - this is why standard old Rover engines/pumps still work with only 15psi of pressure. The bearing surfaces generate their own very high hydrostatic pressures in the oil film during rotation but you need the flow to stop the film overheating.

Also as you say, standard LP feed hose size for dry sump installation is either 5/8 or 3/4 even if the tank is only a few feet away.

Russ