View Full Version : What I learned Saturday. Water Pump. Elec vs Belt


hhott71
07-20-2009, 02:41:31 PM
I have used the Moroso electric water pump kit on the Racecar since 2001 as it was on the Vega when I bought the car.
After rolling the Vega a couple of years ago I installed the engine and trans in the Camaro.
Still using the Moroso water pump drive because Overheating was never a problem and I could circulate the water through the radiator in the staging lanes with the engine off to cool it quickly if needed.

Saturday, the Electric motor gave up and shorted out on the return road.
That was the first time run so I had time to R&R the electric set-ups cog pulley and install a stock water pump pulley and belt. Then ran the second time run.

I turned 11.518 @115.41 with a 1.5902 60' in the left lane on the first time run.
I turned 11.546 @115.38 with a 1.6084 60' in the right lane on the 2nd time run.

Looking at the incremental and MPH's it appears that the Engine driven water pump (AKA Stock) is as efficient as using a Moroso electric water pump drive. As far as ET, MPH, and HP is concerned.

First round I had 1 1/2 cars on my opponent at the stripe. I ran 11.51 @ 112 getting out of it so I wouldn't break out, but I did on my 11.54 dial-in.
He ran 11.06 @ 112 on his 11.04 dial-in. His normal MPH is 121 My bad for leaving a 1.5 car margin. As he could see he wasn't going to catch me so he dumped even more that I did. My R/T was 0.0290 vs 0.0904

73RS
07-20-2009, 02:47:43 PM
I always wondered about those electric water pumps, they really pull some amps and if your running an altenator those amps being pulled by the pump are then being made up by the altenator. Good info, thanks.

Twisted_Metal
07-20-2009, 03:20:14 PM
The power is never free.
I'm glad to see the stock stuff still works well in a direct performance comparison! :D

It would be interesting to unplug the alternator and run on the battery alone for a pass.
I'm curious if any voltage drop would cost you more in ignition performance than the alternator load itself.

Mwilson
07-20-2009, 04:36:41 PM
The power is never free.
I'm glad to see the stock stuff still works well in a direct performance comparison! :D

It would be interesting to unplug the alternator and run on the battery alone for a pass.
I'm curious if any voltage drop would cost you more in ignition performance than the alternator load itself.


I took off my alt belt once and picked up 1/10

Twisted_Metal
07-20-2009, 05:34:22 PM
I took off my alt belt once and picked up 1/10

If it's worth that kind of gain..... Why only once?

Todd80Z28
07-20-2009, 05:46:28 PM
If it's worth that kind of gain..... Why only once?'cause he didn't want to end up with a dead battery?:innocent:

Mwilson
07-20-2009, 06:51:41 PM
'cause he didn't want to end up with a dead battery?:innocent:

Yep! I ran a string of 12.04-12.06 about 10 passes and I said I wonder what would happen if I took the belt off, I wanted an 11.XX so bad. Very next pass only difference was alt belt off and I ran 11.94 my first 11sec pass ever!

GoldenOne7710
07-20-2009, 08:15:59 PM
Yep! I ran a string of 12.04-12.06 about 10 passes and I said I wonder what would happen if I took the belt off, I wanted an 11.XX so bad. Very next pass only difference was alt belt off and I ran 11.94 my first 11sec pass ever!
Dang....how much did that belt weigh???:confused:

Mwilson
07-20-2009, 09:14:42 PM
Dang....how much did that belt weigh???:confused:

bout 200lbs lol, I assume it was the drag on the engine, Ive done it a few times in the past and always gained around 1/10 so I had to do it being so close to 11's at the time.

vegas1974z28
07-21-2009, 01:22:40 AM
I lost my belt after the burnout...Ran a 10.81 on a 10.84 slamming on the brakes...mph was like 110.

But HHott you only run the electric h20 to cool bt rounds right? I have a spare motor I keep in the truck...just in case. And guess what happened....I lost the cog and the belt one night..lol Yeah I just have not had good luck lately.

muscl car
07-21-2009, 06:48:09 AM
you could do this old trick we did back in the 70's .......... find the alternator field wire and splice in a toggle switch in your dash somewhere .when you get ready to run the 1/4 just hit the switch and you'll easily drop your ET by a 10th or more

Simon@London
07-21-2009, 08:33:05 AM
you could do this old trick we did back in the 70's .......... find the alternator field wire and splice in a toggle switch in your dash somewhere .when you get ready to run the 1/4 just hit the switch and you'll easily drop your ET by a 10th or more

The old school guys know all the tricks.

And to think people always wondered what all those spare toggles on the dash were for.

Mwilson
07-21-2009, 09:29:44 AM
you could do this old trick we did back in the 70's .......... find the alternator field wire and splice in a toggle switch in your dash somewhere .when you get ready to run the 1/4 just hit the switch and you'll easily drop your ET by a 10th or more

I used to have one in my car, when I got to the ned of the staging lanes id flip the switch shut the car off then restart and when I came through the lights Id flip it on.
Ive run the moroso drive kit as well for 10 yrs original motor & belt, been considering swapping to conventional belt pully lately just for the heck of it but the car runs so cool and I can cool while its off.