2 replies to this topic

[rabidh]

I really like the idea of an electric water pump - which would mean I could remove the drive chain to the balance shafts and water pump, and get the power without worrying about bunging up oilways. I guess it would gain me about 20bhp at the high end (but the power for the EWP would take some of that I guess).

It seems to have been suggested before, but lots of people have said they wouldn't do it because of reliability. The only electric pump I can find seems to be the Davies Craig EWP80 (or 110) :

-= EWP80 on Demon Tweaks =-

Thats got a worryingly short life of 2000 hours (I guess on average i'm in the VX220 for 1.5 hours a day - so it would only last for about 4 years). I also heard someone say it'd do engines up to about 5 litres (so it seems a bit heavy duty). Does anyone know of any other pump with better reliability? Has anyone on here actually fitted one? (did Ricky?)

it just seems like a pretty easy thing to fit (i can't remember exactly about the water pump on the Z22SE, but i think i could remove the vanes from the existing one and splice the EWP into the big ally pipe that goes alongside the engine on the exhaust side. It'd be a pretty good fix, and with a decent temperature monitor I could get faster warm-up on the engine as well as being able to keep the pump running for a bit after I turned the engine off.

[Winstar]

One of my jobs at Lotus was to size the water pumps for the cooling systems and although they say it'll produce 80 l/min that's probably at 0 pressure head, the z22se has alot of piping to get to the front rad and runs a u flow configuration that gives good wall velociteis but a high pressure loss. To find out if a pump is suitable you really need the pump characteristic to see how the flow changes with pressure head. Off the top of my head 80 l/min sounds low but that's be OEM sizing guidelines The other thing to be aware of IIRC the power consumtion of water pumps isn't very linear, so while you gain at the very high revs, alot of the time you'll not see much advantage, esspecially with the std rev limit. Personally if it was me I'd not bother on a road car, it's the type of mod you do to a race car that will spend all it's time bouncing off the limiter and requires every last bhp. But if you want a hand with the sums let me know.

Edited by Winstar, 19 July 2007 - 11:38 AM.

[Steve Crisp]

What about a belt-driven pump? One that'd fit on the outside of the engine and get it's drive from the alternator belt? There must be loads to choose from... Steve