Neutron

iTrader: (10)

Hi everyone,

First, I would like to preface this post. This is not a necessary mod! The factory water pump works great! Especially for a street car, which my car is. This is just a post on what I did and I am hoping someone finds it interesting.

For me, I really wanted the real estate provided by removing the water pump housing to do something unique with the turbo setup. I had already moved to an EWP and had done so years ago. Standard affair Davies Craig EWP150. Initially, as most probably do, I used the Davies Craig EWP controller which works well enough. Eventually I ditched the Davies Craig EWP controller in favor of controlling the pump from the HB output to SSR from the ECU. In either case, getting consistent temp control was very difficult. For a normal street car over cooling was a constant issue. With primetime driving here in AZ being September to early June, the winter months would often result in very cold engine temps. Any steady state driving on the freeway would result in temps in the low 130 to high 120’s no matter what the pump speed was set at. I obviously did not want pump speed duty cycle to be too low as this could cause misleading readings and inconsistent temps in the block due to a huge lack of flow. The dream scenario for me would have pump speed be 100% independent from engine speed and coolant temperature. That is what I set out to do and have accomplished.

The easiest way to accomplish this would be to incorporate a thermostat back into the coolant system. I originally tried this with the original Davies Craig EWP150 using an inline thermostat. Packing was just a nightmare to get right. Main thing for me is it was going to look horrible. After doing a little research, I found that Meziere offers remote EWPs with integrated thermostats with bypass built in! After getting measurements and going over how this may work with my fab guy, we determined it could work and would be the cleanest solution by far. The water pump in question is the 55GPM WP365S.

Truth be told, this was a lot of work to get right. My fab guy is amazing and knocked it out of the park. I have been driving on this setup for a few months now and could not be happier with the results. No matter the temp outside, coolant temps are high 180’s to low 190’s. So far my lowest outside temps were high 20’s and highest temps have been close to 90. Being in AZ, much higher temps will be coming soon.

Hopefully someone finds this interesting. Again, 100% unnecessary for just about anyone else but I am really happy with how this turned out.

Raw materials from Fab (Radiator is missing from this pic.)


Testing different pump vibration isolators. 70 duro

sorbothane bushing

sorbothane bushing

and

washers

washers

were a perfect fit and have a load rating way higher then the pump weight


Mocking up pump, mount and creating 16AN pump output coolant hose to engine and 3/4" coolant bypass


Mocking up outer radiator and v-mount ducting and undertray supports


New radiator back from getting black ceramic heat dissipation coating. Mocking up radiator ducting.


Mocking up top of the radiator with ducting and v-mount/air filter separation ducting


Prepping to seal radiator fan shroud


Mocking up radiator mounting with ducting


Top view of mocked up radiator mounting with ducting


Finishing making radiator input and output 16AN coolant hose.


Top view of finalized 16AN coolant hose routing and 3/4" bypass


Sealing up duct work and test fitting air filter

Neutron

iTrader: (10)

Bottom view of test fitting and sealing duct work


Bottom view of radiator with shroud and air filter protection plate


Fitting under tray


Burping the system and testing for leaks. Most of this was done with the car off.


Final engine bay after driving on the new coolant system setup for a few months

R-R-Rx7

iTrader: (24)

I have been debating switching to the DG EWP150 for a while but i have yet to do my homework properly.
thanks for this great write up. Very informative

TwinCharged RX7

iTrader: (14)

Nice work. What do you think made it uncontrollable without the thermostat? I’ve been planning do go electric, but figured running the pump at 5% volume or less via PWM control when the engine is under temp would work.

Neutron

iTrader: (10)

I'm certainly not an expert but there is a certain threshold in duty cycle where the pump is not going to respond, as in literally no flow through the block. I do not know exactly what that is but 30% was as low as I was comfortable going. This will lead to hot spots that you will not necessarily see in your temp sensor. I was probably being overly cautious but I do know having a ton of flow through the block while being able to regulate a constant temp is a good thing.

TwinCharged RX7

iTrader: (14)

Interesting. I was planning to use this pierburg pump (common on BMW). Will have to do some testing on how low it will flow. Had not thought about that.

mr2peak

What manifold are you using?

Carlos Iglesias

iTrader: (6)

First off, full marks on the idea, design, and execution!

For the other's considering EWP, do you know what the temp-to-pulsewidth/voltage programming was on your original DC setup. The DC controller uses is a variable voltage control system, though most ECUs use a Pulsewidth/duty cycle control of the coolant pump/fan. Since DC has become the defacto EWP in many builds, your feedback could be valuable to your gentle readers with similar concerns.

What about this setup... is the thermostat point adjustable? If so, could you share the set points and flow profiles (i.e. duty cucle/voltage to collant temp)?

Super innovative and the duct work is brilliant, so thanks for sharing.

Neutron

iTrader: (10)

It's a custom one off manifold. This turbo placement is not possible with the factory water pump housing.

Neutron

iTrader: (10)

Thanks for the kind words. I really appreciate it.

The original DC controller was the standard Davies Craig EWP and coolant fan controller. I personally had the controller target temperature set to 190F. Looking at the Davies Craig website, there is an updated controller so I was using their previous model.

The Merize pump is using a 179F thermostat from a Chevy V8. It's very simple. As far as ECU setup, I am using PWM at 200hz, which the pump and SSR are very happy with. Warm up at 30% duty, which is still very strong on this pump. Running a max of 90% duty. Pump is honestly way more then a 2 rotor needs.

TeamRX8

iTrader: (2)

honestly, it sounds to me like it just needed the old racer trick; a plate with a properly sized hole in it where the t-stat would normally be. Because what you described is exactly what I recall was reported to happen without the “orifice” plate.

I thought it used to be listed on the Racing Beat website, but now it says not to do that and that free-flow is best . Could have sworn it was about the equivalent to a thermostat with the guts pulled out of the center. Which means it would be about the same or maybe a little less backpressure as a fully open t-stat. Maybe I’m completely wrong on it since I can’t seem to find anything to back it up.
.

Neutron

iTrader: (10)

You're right. some sort of restriction would work but im sure there some trail and error there. I did think about giving that a try. Ultimately I wanted to remove the water pump housing all together and knew just adding a thermostat back in was a good solution.

Neutron

iTrader: (10)

I was informed by someone that wanted to view the photos in this thread that all the links were broken. Turns out google changes the format and how imbedded links from google drive work. Every embedded photo I have to my google drive account is probably broken. Reposting the photos in this thread. I also do have an update which I will post when I get more time. I never did a follow up since I did not think anyone was really interested in this idea.

Raw materials from Fab (Radiator is missing from this pic.)


Testing different pump vibration isolators. 70 duro sorbothane bushing sorbothane bushing and washers washers were a perfect fit and have a load rating way higher then the pump weight


Mocking up pump, mount and creating 16AN pump output coolant hose to engine and 3/4" coolant bypass


Mocking up outer radiator and v-mount ducting and undertray supports


New radiator back from getting black ceramic heat dissipation coating. Mocking up radiator ducting.


Mocking up top of the radiator with ducting and v-mount/air filter separation ducting


Prepping to seal radiator fan shroud


Mocking up radiator mounting with ducting


Top view of mocked up radiator mounting with ducting


Finishing making radiator input and output 16AN coolant hose.

Neutron

iTrader: (10)

Top view of finalized 16AN coolant hose routing and 3/4" bypass


Sealing up duct work and test fitting air filter


Bottom view of test fitting and sealing duct work


Bottom view of radiator with shroud and air filter protection plate


Fitting under tray


Burping the system and testing for leaks. Most of this was done with the car off


Final engine bay after driving on the new coolant system setup for a few months

Slides

Just for those playing at home, at highway cruise convection is enough to maintain coolant flow through the system, you can throw a belt and not run over-temp. A bypass style thermostat that continuously circulates through the block and progressively bleeds to the radiator is ideal for consistent engine temperature. Some guys on Ausrotary.com worked out a round about way of doing it with a blanked factory housing and EWP a long time ago, obviously if doing it for packaging reasons you need an appropriate external unit and circuit layout.

The bleed port thermostat setup and old school racers not used to it is where all the old wives tales about coolant going "too fast" to absorb heat from the engine came from. These guys went from really basic bleed through thermostat systems where you could just terff the thermostat for full flow to block flow bypass systems, they removed the thermostat without blocking the bypass and wondered why they ran hot, funnily enough a fair bit of the flow took the shortest route back to the pump through the block still hot.

gracer7-rx7

iTrader: (16)

In case people were not aware of this, Sakebomb Garage @SakeBomb Garage has an electric water pump setup. They posted about this on the forum a few years ago when they released the product.
https://www.sakebombgarage.com/sbg-c...kit-fd3s-rx-7/

Neutron

iTrader: (10)

The point of this is not the EWP. That is pretty proven and has been around for quite awhile. I've used an EWP for over a decade. It's simply to show the the route I took to integrate a thermostat with bypass with an EWP. It's just a more reliable way to maintain a better operating engine temperature. I'll post an update when I have time. I tested a few revisions on this setup since the last time I posted.

TeamRX8

iTrader: (2)

deleted -unnecessary

gracer7-rx7

iTrader: (16)

Ah, got it. Didn't notice that with the SB product.

SakeBomb Garage

iTrader: (17)

We'll have a solution that keeps the thermostat in the next month Can't say much more but we're nearly done with production!

-SBG

Monkman33

iTrader: (28)

About time!

TwinCharged RX7

iTrader: (14)

Here is an easy option. $32

Neutron

iTrader: (10)

I have played with at least 3 different OEM inline thermostats and a custom inline thermostat. I could not get any of them to fit. It's probably has to do with my setup with a very large vmount radiator and IC. I would interested to see someone get one of these to work cleanly. Not at all trivial!

TeamRX8

iTrader: (2)

the pump isn’t cheap, or light, but it apparently does the job well.

this is another option; same as an inline oil cooler t-stat setup but rated to 50 gpm on water. Eliminates having a 3rd hose assembly

https://www.improvedracing.com/flow-...hermostat.html
.