Hank.

I have a 2600lb '88 Mazda RX-7 with a 2002 LS1 motor. It's built with Z06 heads, F14 cam, ~430RWHP. In trying to make the car more reliable for road racing I was thinking of eliminating all accessories except the alternator. Has anyone here successfully roadraced with an electric water pump (Meziere, Evans, etc)? If so, what pump did you buy? The Meziere LS1 street pump flows 55gpm and it has provisions for a heater core. I don't have a heater core, so I thought about opting for the heavy duty race version at 45gpm. The standard race version is 35gpm.

I realize the life of the pump is guesstimated at 3000 hours. I'll wire in an hour meter to check on that. The car will see street duty from time to time, but it will mostly be trailered to road course events.

Searching quite a few message forums only yields discussions on drag racers forking the cash out for a few HP gains and the ability to cool the car in the staging lanes quicker. I don't worry about that. I'm worried about 45 mins of 4000-7000rpm bursts at Road Atlanta, TWS, Barber Motorsports Park, etc.

FWIW, Meziere recommended their high pressure, high flow mechanical water pump. It flows 120gpm at 5000rpm. Wowzers. I called LG Motorsports and they recommended the stock water pump. IF the EWP can survive I would like to clean up the engine bay, add to the reliability of only one small belt, and the bling factor.

Any help would be greatly appreciated.

Mojave

iTrader: (4)

Several people have talked about this, but I don't think an electic water pump can keep up for extended use at high RPMs. I think above 4000 or 4500, the stock pump is flowing more, and if you are spending significant amounts of time at high RPMs, a regular mechanical pump is better.

In my LS1, I run TWS in 3rd and 4th, and most of the time the car is over 4K.

Save your cash and spend it on track time!

WAHUSKER

iTrader: (4)

Boyce (NataSS Inc) ran a Mezierre on his open road race car. Under 4500 like around town & at the drag strip it cooled fine, but his car ran extended periods above 5K in ORR & it got HOT there.

I have one on my car & during the track session I just did it was fine. It did over heat during my cone training exercise (accelerate, turn hard, slam on the brakes, idle for 5 minutes, start over....lasted ~1 1/2 hrs)

I can also tell you it is worth 15hp on the dyno & >1/10th at the drag strip.

A502slo

iTrader: (4)

Ok this is a dumb ?? but can you port or polish the stock water pump???

Mojave

iTrader: (4)

I doubt you need to. The stock LS1 pump works perfectly fine for road race use. There is really no need to be messing with the cooling system unless you actually have a problem.

turbogarrett

iTrader: (8)

Like I said at v8rx7forum, I've had zero problems with the meziere pump for 20 minute sessions. I have logged sessions and never seen over 200* on the track. I have a mti x1 cam(230/227) and usually shift the car between 62-6400. Proper ducting, radiator setup and of course getting all the air out of the system will be more important for short hpde style stuff imo.

Since your car is primarily a roadcourse toy with a larger cam I would just save the $5xx and follow the pros here.

Hank.

I appreciate the comments here. Between your responses as well as a few well known vendors it looks like I will retain the stock water pump. I take it I can put a rubber 180 on the side of the water pump case since I'm not running a heater core?

Mojave

iTrader: (4)

Yes, that will work.

pavell

In response to your latest question, as Mojave mentioned, you should not have any issues using a rubber 180.
Agreed.