.

 

I found when running my electric water pump that the cooling is far more effective than the stock water pump. This is because the water flow rate can be held high at all RPMs and the higher the flow rate the more effective the cooling. I measured the temp at the entrance to the head and exit from the block and with the EWP at 50% pwm I saw less than 1 degree Celsius difference. Mind you the water is flowing fairly rapidly, even at 50% pwm.

If you remove the thermostat on the stock system the engine will run far cooler on a track and that's because the thermostat even when open is a restriction point. Ignore all that BS about the pressure differential a thermostat creates, that's just wrong. If you are a running a stock car on the track a lot, you don't need the coolant re-route or anything like that. The direction and path of the flow only matters if the coolant is flowing slowly through the engine. If it's pumped through at pace the temperature differential is dropped to less than a few degrees, plus there are no stagnant areas. All you need is to bypass the thermostat when at the track and make sure your radiator is getting clean airflow.

Has anyone made a bypass kit?

 

I disagree with your assertion that water flow negates the need for a reroute but let's just agree to let that one lie.

I do agree that increased water flow improves cooling. During my build I sourced a high flow motorad thermostat and drilled two 1/4" holes where the bleed holes were to get additional flow. Because of my improves radiator setup the car would never warm up past 120 degrees. My setup is far from stock, but it opened my eyes to how cyclical the heat load can be on a cooling system. On a stock system with a bypass you would have to pull onto track with a relatively cold engine and beat on it to get it up to temp. You would also get some pretty wild wings in temp depending on ambient conditions and track speed.

An improved setup might be too have dual high flow thermostats, either in a custom housing or just run a reroute and the stock route and merge the two outlets.

If I was designing the system from scratch I would have a radiator bypass loop, this way you have full coolant flow and a steady minimum temp.

 

I never found a thread dedicated to ducting so I figured this would be the most logical place to ask a intercooler / radiator ducting question.

I spent way too much time over the last few days fabricating ducting in the nose of my 91 in hopes of improving my on track cooling issues.

I've got a Percision 350 intercooler and I'm upgrading to a TSE crossflow radiator with a single 13" Spal low profile fan to clear my RB hollow bar and bar brace. No AC and I just pulled the power steering out. I'm making about 170hp with 10psi on my modified Greddy kit.

I used a bunch of 6" aluminum flashing and about a 1/2" a roll of foil tape. I'm going to use weather stripping to complete the seal from the back of the "box" to the radiator.

My question is if I should duct the back of the IC into the radiator to keep air from going around the back of the IC on its way to the radiator? I was thinking that if air from the intake was building up in front of the radiator it could impeed the air trying to travel through the IC fins. However, this will also presumably make an IC sized rectangle of air in the middle of the radiator that is not as cool or fast as it first has to go through the IC.

I want to figure this out before I finish up and permanently install the radiator.

your input would be greatly appreciated. I'll be putting my mesh stone guard grill in front of the opening.
A little air can pass under the IC but there is a good opening above that covers about half of the top of the radiator.
Here you can see there is about a 1-1.5" gap between the back of the IC and the front of the radiator.
The back of the box lines up the finned area of the radiator but not wide enough to hit the side tanks. This is the edge where I'll put weather stripping to seal up to the radiator

 

.

 

Allow the air to go around the intercooler to the radiator.

 

Thanks for the feedback. I guess considering that the intercooler is rated at 2X the HP than my little turbo setup can make and it's in the best position to get blasted by air, making sure as much air as possible is hitting the radiator is the most critical.

I'm definitely thinking about venting the hood at some point as well as an oil cooler. Since my next track day is on May 3rd and I always seem to run out of time on car projects I'll probably just concentrate on getting the new radiator back in, doing a coolant flush, and looping my depowered rack lines.

I also have to get a new digital temp gauge in (this will be my 3rd one) because the other ones would give me normal temp and then suddenly climb to crazy high temps. Very frustrating! The only thing I can seem to rely on is when my MS2e from MSLabs starts flickering and then blinking the check engine light. The stock gauge barely starts to move when my MS is telling me to shut it down and take a cool down lap. I definitely need a more obvious way to track my temp.

 

Monitor oil temps.

And water temp sensor placement can cause strange jumps at times due to thermostat opening and closing, depending upon the presence of bypass holes. So can air pockets in the system. The sensor won read right if the coolant isn't touching it, then will jump up when it does.

 

The aftermarket water temp sensor is mounted in the BEGI coolant reroute spacer on the back of the head just before the thermostat. I've backed it out with coolant in the system in hopes of releasing any trapped air but it didn't make any difference. (Of course the engine was cold at the time so it probably wasn't super effective)

Since I'm going to refill the system again with the new radiator, how high over normal over normal do I need to raise the front end? The last time I did it I drove the front end up on Rino ramps (I'd say about 9" under the front wheels) with the cap off until the engine warmed up enough to open the thermostat. Do I have to get it up more significantly than that to get any bubbles out?

On the same subject of coolant, I'm going to use water and a water wetter after I do the coolant flush. I read on a bottle of Lucas Oil Super Coolant that you should not use distilled water unless you are doing a 50/50 mix with antifreeze (https://lucasoil.com/products/proble.../super-coolant )

 

I've not heard of anyone recommending against distilled until this. Our tap water will eat through the copper piping in home plumbing in 10 years. We must plumb with pvc. It will eat a radiator or heater core in a few years.

 

I want to know why too.

 

Do you own The Magic Funnel™? It works with the TSE rad and you want it in your toolbox.



Buy that, block rear wheels, get the nose up as high as you are comfortable raising it (we got the exo off the ground like 2' with @gesso's giant 4x4 jackstands, lol) apply funnel, fill with coolant, let it run for like ~10 minutes, observe the magic, win at cooling system refill.

And the Mazda FSM & Owners Manual also state you must use antifreeze as well

Cooling system is something like 6.2 quarts? I personally use a gallon of distilled water, a bottle of Redline Water Wetter, and then top it off with premix. There is just enough antifreeze in there to keep the inevitable becauseracecar coolant system corrosion in check (and also help me sleep during the 3 nights a year we get below freezing) but not enough ruin everyone's weekend should I pop my cooling system on track.

 

With the magic funnel you don't even need to raise the nose.

--Ian

 

Yeah, but its more fun my way.

(plus it took forever without the nose elevated, and I'm both lazy and impatient)

 

With a reroute I think raising the nose risks trapping air in the front of the head.

 

I have a reroute and a TSE rad -- magic funnel did it with about 5 minutes of idling and no nose raising.

--Ian

 

+1, I now use the funnel and leave the car level.

 

I go back and forth between the nose raised and not raised. Generally it depends on if the car was on jack stands or not.

​​​​​​​My method is to let the fans cycle on and off 3 times and then call the system burped.

 

My TSE radiator just got delivered, it's massive. Still need to order a fan, and a turbo blanket to add to my arsenal which includes a 25 row TSE oil cooler. Hopefully it'll be enough to beat the heat at the track.

 

You don't want a turbo blanket. Use a stock fan.