Go Back   Rotary Car Club > Tech Discussion > RX-7 2nd Gen Specific (1986-92)

RX-7 2nd Gen Specific (1986-92) RX-7 1986-92 Discussion including performance modifications and technical support sections.


Welcome to Rotary Car Club.

You are currently viewing our boards as a guest which gives you limited access to view most discussions and access our other features. By joining our free community you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is fast, simple and absolutely free so please, join our community today!

If you have any problems with the registration process or your account login, please contact contact us.

Reply
 
Thread Tools Display Modes
Old 11-19-2011, 01:25 PM   #1
sen2two
KTEC
 
sen2two's Avatar
 
Join Date: Jan 2009
iTrader: (2)
Posts: 642
Rep Power: 0
sen2two is on a distinguished road
Default electric water pump on the street

Every now and again I want to drive my car on the street to meets and shows. It's legal and with the muffler it's not that loud, but I have a smaller radiator and electric water pump. anyone ever have any problems driving on the street with a similar set up? Motor is a stock un-ported 13b with stock turbo.






__________________
what I have:
1985 Gs:12a All motor Drag car - 1973 Rx2: Play car
What I had:
93 Touring: TRADED - 91 Coupe: TRADED - 90 GTU: RHD - 88 10AE: SOLD - 87 Base: SOLD - 86 Base: SOLD - 1985 GSLSE - 85 Gsl: SOLD - 80 Gs: TRADED - 1972 Rx2
sen2two is offline   Reply With Quote
Old 11-19-2011, 06:07 PM   #2
Monkman33
Still Building my FD
 
Join Date: Jun 2009
Location: Pasco, WA
iTrader: (1)
Posts: 255
Rep Power: 16
Monkman33 is on a distinguished road
Default

my weekend warrior/autocross car will have an ewp setup. I am also going to have a warning system in stages if my water temps start rising too high to let me know of a water pump failure.
__________________
Uh.... hi.
Monkman33 is offline   Reply With Quote
Old 11-20-2011, 10:21 AM   #3
730RWHP12A
Rotary Fanatic
 
Join Date: Mar 2008
Location: chatsworth, california
iTrader: (8)
Posts: 349
Rep Power: 17
730RWHP12A is on a distinguished road
Default

what kind of pump is it?
__________________

rotaryshack.com
730RWHP12A is offline   Reply With Quote
Old 11-20-2011, 01:51 PM   #4
sen2two
KTEC
 
sen2two's Avatar
 
Join Date: Jan 2009
iTrader: (2)
Posts: 642
Rep Power: 0
sen2two is on a distinguished road
Default

Meziere inline pump. I believe it flows at 20 GPM and I am using -16 hose and AN fittings.
__________________
what I have:
1985 Gs:12a All motor Drag car - 1973 Rx2: Play car
What I had:
93 Touring: TRADED - 91 Coupe: TRADED - 90 GTU: RHD - 88 10AE: SOLD - 87 Base: SOLD - 86 Base: SOLD - 1985 GSLSE - 85 Gsl: SOLD - 80 Gs: TRADED - 1972 Rx2
sen2two is offline   Reply With Quote
Old 11-22-2011, 08:30 AM   #5
730RWHP12A
Rotary Fanatic
 
Join Date: Mar 2008
Location: chatsworth, california
iTrader: (8)
Posts: 349
Rep Power: 17
730RWHP12A is on a distinguished road
Default

Quote:
Originally Posted by sen2two View Post
Meziere inline pump. I believe it flows at 20 GPM and I am using -16 hose and AN fittings.
you will be fine
__________________

rotaryshack.com
730RWHP12A is offline   Reply With Quote
Old 11-20-2011, 04:37 PM   #6
Mazdabater
FC3S
 
Join Date: Jun 2010
Location: Townsville, QLD, AUS
iTrader: (0)
Posts: 326
Rep Power: 15
Mazdabater is on a distinguished road
Default

Correct me if I'm wrong but isnt the main point of an ewp to keep the flow constant at its most efficient point? As opposed to a belt driven pump that varies at rpm, I would have thought it would be better on the street as your pumping more fluid at idle.
Mazdabater is offline   Reply With Quote
Old 11-20-2011, 07:57 PM   #7
Monkman33
Still Building my FD
 
Join Date: Jun 2009
Location: Pasco, WA
iTrader: (1)
Posts: 255
Rep Power: 16
Monkman33 is on a distinguished road
Default

http://www.stewartcomponents.net/Mer...Code=ElectPump

This is the one I have on order. It has a controller on it so it varies the flow based on current temperature.

Also, I want to be able to run the pump after the engine is off for even cooldown.

Plus, this has a max flow rate the should exceed the max needed flow.
__________________
Uh.... hi.
Monkman33 is offline   Reply With Quote
Old 11-21-2011, 10:34 AM   #8
sen2two
KTEC
 
sen2two's Avatar
 
Join Date: Jan 2009
iTrader: (2)
Posts: 642
Rep Power: 0
sen2two is on a distinguished road
Default

Quote:
Originally Posted by Mazdabater View Post
Correct me if I'm wrong but isnt the main point of an ewp to keep the flow constant at its most efficient point? As opposed to a belt driven pump that varies at rpm, I would have thought it would be better on the street as your pumping more fluid at idle.

Not really. Its to reduce friction on the crank to gain more a few more HP. Especially in the top end of NA cars.
__________________
what I have:
1985 Gs:12a All motor Drag car - 1973 Rx2: Play car
What I had:
93 Touring: TRADED - 91 Coupe: TRADED - 90 GTU: RHD - 88 10AE: SOLD - 87 Base: SOLD - 86 Base: SOLD - 1985 GSLSE - 85 Gsl: SOLD - 80 Gs: TRADED - 1972 Rx2
sen2two is offline   Reply With Quote
Old 11-21-2011, 12:48 PM   #9
Pete_89T2
Lifetime Rotorhead
 
Pete_89T2's Avatar
 
Join Date: Apr 2010
Location: Elkton, MD
iTrader: (1)
Posts: 874
Rep Power: 15
Pete_89T2 is on a distinguished road
Default

^These are both valid advantages for an E-water pump. Being able to control flow rate independent of RPM helps to optimize the efficiency of the cooling system, all other things being the same, and switching to an EWP should get you a net reduction in parasitic loads at the crank. I say "net reduction" because the electrical power needed to run an EWP isn't free - the alternator will have to work harder (more drag on the crank) to produce that power. The question is does the increase in parasitic drag from the alternator get offset by a larger decrease in parasitic drag from the mechanical water pump?
Pete_89T2 is offline   Reply With Quote
Old 11-21-2011, 02:11 PM   #10
My5ABaby
Sigh.....
 
My5ABaby's Avatar
 
Join Date: Feb 2008
Location: Murfreesboro, TN
iTrader: (6)
Posts: 2,377
Rep Power: 19
My5ABaby will become famous soon enough
Default

Quote:
Originally Posted by Pete_89T2 View Post
^These are both valid advantages for an E-water pump. Being able to control flow rate independent of RPM helps to optimize the efficiency of the cooling system, all other things being the same, and switching to an EWP should get you a net reduction in parasitic loads at the crank. I say "net reduction" because the electrical power needed to run an EWP isn't free - the alternator will have to work harder (more drag on the crank) to produce that power. The question is does the increase in parasitic drag from the alternator get offset by a larger decrease in parasitic drag from the mechanical water pump?
And to expand on it, is the offset even worth it?
__________________
1986 Sport: 132k miles, 5A (Sapphire Blue Metallic), Tokico Blues, Racing Beat Springs, Custom LED tailights (only S4 LED tails in the world), SSR Mark II, Racing Beat exhaust, S5 black interior, Rotary Resurrection rebuild at 120k miles

Community Service Manual

RotorWiki

"Imagination costs nothing; we could build square locomotives or fly to Mars" - Felix Wankel

Yesterday is history, tomorrow is a mystery, but today is a gift. That is why it is called the "present."
My5ABaby is offline   Reply With Quote
Old 11-21-2011, 02:17 PM   #11
sen2two
KTEC
 
sen2two's Avatar
 
Join Date: Jan 2009
iTrader: (2)
Posts: 642
Rep Power: 0
sen2two is on a distinguished road
Default

Dynos have proven to give up to 20 whp when switching to an electric water pump at the top end of high rpm engines like PP 12a's and 13b's.

So yes, its worth it.
__________________
what I have:
1985 Gs:12a All motor Drag car - 1973 Rx2: Play car
What I had:
93 Touring: TRADED - 91 Coupe: TRADED - 90 GTU: RHD - 88 10AE: SOLD - 87 Base: SOLD - 86 Base: SOLD - 1985 GSLSE - 85 Gsl: SOLD - 80 Gs: TRADED - 1972 Rx2
sen2two is offline   Reply With Quote
Old 11-21-2011, 02:49 PM   #12
My5ABaby
Sigh.....
 
My5ABaby's Avatar
 
Join Date: Feb 2008
Location: Murfreesboro, TN
iTrader: (6)
Posts: 2,377
Rep Power: 19
My5ABaby will become famous soon enough
Default

Quote:
Originally Posted by sen2two View Post
Dynos have proven to give up to 20 whp when switching to an electric water pump at the top end of high rpm engines like PP 12a's and 13b's.

So yes, its worth it.
Whut... My waterpump is using 10% of my HP?
__________________
1986 Sport: 132k miles, 5A (Sapphire Blue Metallic), Tokico Blues, Racing Beat Springs, Custom LED tailights (only S4 LED tails in the world), SSR Mark II, Racing Beat exhaust, S5 black interior, Rotary Resurrection rebuild at 120k miles

Community Service Manual

RotorWiki

"Imagination costs nothing; we could build square locomotives or fly to Mars" - Felix Wankel

Yesterday is history, tomorrow is a mystery, but today is a gift. That is why it is called the "present."
My5ABaby is offline   Reply With Quote
Old 11-21-2011, 03:08 PM   #13
Pete_89T2
Lifetime Rotorhead
 
Pete_89T2's Avatar
 
Join Date: Apr 2010
Location: Elkton, MD
iTrader: (1)
Posts: 874
Rep Power: 15
Pete_89T2 is on a distinguished road
Default

Quote:
Originally Posted by My5ABaby View Post
Whut... My waterpump is using 10% of my HP?
That does seem like a lot of power just to run a water pump... Sen2two, were the quoted dyno figures from a before & after test, where the only thing they changed between the two runs was the water pump?
Pete_89T2 is offline   Reply With Quote
Old 11-21-2011, 04:31 PM   #14
Kentetsu
RCC Contributor
 
Kentetsu's Avatar
 
Join Date: Feb 2008
Location: Grand Rapids, Michigan
iTrader: (1)
Posts: 530
Rep Power: 17
Kentetsu is on a distinguished road
Default

More importantly, was the pump actually running when they checked the dyno results? Maybe 20hp is what you get simply by removing the water pump from the equation altogether...




.
__________________
"Learn from the past, or it will become your future...."

'85 GS 12a + LSD/Sterling carb/Respeed coilovers/Respeed front swaybar/Respeed adj. rear spring perches/Illuminas/Bilsteins on rear

AutoX vids @ http://www.youtube.com/user/Kentetsu1
Kentetsu is offline   Reply With Quote
Old 11-21-2011, 05:23 PM   #15
sen2two
KTEC
 
sen2two's Avatar
 
Join Date: Jan 2009
iTrader: (2)
Posts: 642
Rep Power: 0
sen2two is on a distinguished road
Default

This was not done on my car. I've seen it done on various cars throughout the years. Rotary and piston alike.

There's a reason that almost all serious drag cars use them. My question is not if it works, my question is if a combination of a smaller radiator and the electric pump is enough to keep the car cool on the street.

I guess ill just take it for a drive and find out.

Also, a lot of drag racers have the electric pump hooked up to a switch along with the fan. This way you can do the pass and after you cross the line, you turn your fan and pump back on. Reducing the pull from the alternator during the radiator.
__________________
what I have:
1985 Gs:12a All motor Drag car - 1973 Rx2: Play car
What I had:
93 Touring: TRADED - 91 Coupe: TRADED - 90 GTU: RHD - 88 10AE: SOLD - 87 Base: SOLD - 86 Base: SOLD - 1985 GSLSE - 85 Gsl: SOLD - 80 Gs: TRADED - 1972 Rx2
sen2two is offline   Reply With Quote
Reply

Bookmarks


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -5. The time now is 02:45 AM.


Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Hosted by www.GotPlacement.com
Ad Management by RedTyger