Essential cooling mods?

[Tim818]

@Randizzle88 aren’t you guys working on a cooling hood for the FK8 Civic over at Evasive?

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[iqbad]

Someone before me in this thread was thinking in the same direction as me, why don’t we just implement water spray cooling?

From my experience talking to the local tuners here in Sweden, they claim that side mounted oil cooler helps a lot for the cooling issues. Now, outgoing oil temp is usually much higher than water temp, probably closer to 130degC. If we use the existing washer pump, put a small 3-way ball valve on the outgoing pipes, we could redirect and spray Intercooler and oil cooler with water during hard track use. Porsche gt2rs uses this!

Then a small logic that in parallel runs the pump based on for instance oil cooler inlet temp. We could even PWM the pump slowly. The cooling effect would by very high when these hot parts are sprayed.

I think maybe I will just build a kit like this for myself, just have a bit too much at work right now.

 

[oak]

Surprised no one has mentioned removing the upper hood rubber seal against the windshield cowl. Probably the easiest and most bang for the buck. Full flow ventilation. Takes all but 30 secs to remove.

 

[Akuto]

Surprised no one has mentioned removing the upper hood rubber seal against the windshield cowl. Probably the easiest and most bang for the buck. Full flow ventilation. Takes all but 30 secs to remove.

Wouldn't that cause air to move inside the hood and cause hood lift and possibly disturb the heat extractor vents in the air which in turn causes more heat in the engine bay? That affect is called cowl induction, the point where the hood and the windshield meet is a high pressure zone which has turbulent air that tumbles. Cowl induction hoods give this high pressure zone a way to escape, and in that case, into the hood through the opening and channeled towards the carburetor, which is then somewhat acts as a "forced" or "ram" style induction. Since our cars don't use this method or have a top mount intake inlet, we would just see hood lift and turbulent hot air under the hood

 

[Caestus]

I haven't tracked my CTR, as I have a purely track racecar for that (1995 EG with K24/20 frankenstien and BW EFR 7163 turbo). I've owned it since 1997 and it's been a racecar since 1999, first racing in H1 Honda Challenge (with a stock K20) and later converted to the K24/20 and turbo for GTA timeattack and hillclimbs etc). acceptable coolant temp is up to 220. at 235 the warning light comes on (hondata kpro controlled). at 240 I slow down and do cooldown laps to let it recover. acceptable oil temp is up to 260. at 280 I start to worry. at 300 I do cooldown laps. I have a large fluidyne oil cooler and a large radiator but in 90+ deg temps she will overheat in about 5 mins of hard laps. but typically thats 2-3 laps and thats all the tires are good for anyway (295-35-15 hoosier A7s). thats at about 500 whp level. I run 5w-40 Ardeca synth or Motul synth oil. oil looks great even after two weekends hitting 260 deg (shows no signs of real stress); after 2 weekends I change the oil and filter and its ready to go again.

I think the main issue with the CTR is air flow through the grill and through the radiator and exhausting out from under the hood. I had the same issues with my EG; gotta get the air in and out. I cut openings in it and ducted off the radiator and sealed it up so that air can't get around it and escape without going through the rad. that SCCA race guy that I saw at NJMP wasn't overheating and he had done the Ebay grill and cut holes in his hood and installed some cheap vents and he said that that had basically solved his overheating. he added the oil cooler to keep the oil temps below 280 and the turbo blanket because it helps with underhood temps.

Great information. Thank you!

 

[oak]

Wouldn't that cause air to move inside the hood and cause hood lift and possibly disturb the heat extractor vents in the air which in turn causes more heat in the engine bay? That affect is called cowl induction, the point where the hood and the windshield meet is a high pressure zone which has turbulent air that tumbles. Cowl induction hoods give this high pressure zone a way to escape, and in that case, into the hood through the opening and channeled towards the carburetor, which is then somewhat acts as a "forced" or "ram" style induction. Since our cars don't use this method or have a top mount intake inlet, we would just see hood lift and turbulent hot air under the hood

hood lift? haven't experienced any as of yet. Im no expert but from examining the engine bay the hot air that would normally build up in the engine back of the bay would quickly be exhausted with the rubber strip removed. from what I can tell it would be a rather smooth laminar flow out the back of the hood.

 

[TypeSiR]

hood lift? haven't experienced any as of yet. Im no expert but from examining the engine bay the hot air that would normally build up in the engine back of the bay would quickly be exhausted with the rubber strip removed. from what I can tell it would be a rather smooth laminar flow out the back of the hood.

One can do a test but I’d use a shorter streamer than the video. The guy did have a cowl induction hood (reversed hood scoop) vs a normal hood so the effect is magnified.

 

[GeezR]

Eric in Sweden: My turbo'd '05 Evo came with a water sprayer for the intercooler. I'd push the button on straight stretches during track days. I never noticed a difference since, unlike the CTR, the Evo had more than adequate engine bay cooling.

 

[oak]

One can do a test but I’d use a shorter streamer than the video. The guy did have a cowl induction hood (reversed hood scoop) vs a normal hood so the effect is magnified.

thanks for the vid it's clear with the streamers the induction is visable. either way the airflow, down and out or up and out Im sure the heat will get exhausted from the engine bay with out the weather strip. maybe someone inclined can take some engine bay temps with and with out weather strip. it would be interesting to see what if any temp differentials.

 

[Akuto]

hood lift? haven't experienced any as of yet. Im no expert but from examining the engine bay the hot air that would normally build up in the engine back of the bay would quickly be exhausted with the rubber strip removed. from what I can tell it would be a rather smooth laminar flow out the back of the hood.

The silver metal tray at the back end of the hood has vents that lead to the side vents, that is how our hoods deal with air build up in the back, it uses the louver effect to work

 

[Gansan]

thanks for the vid it's clear with the streamers the induction is visable. either way the airflow, down and out or up and out Im sure the heat will get exhausted from the engine bay with out the weather strip. maybe someone inclined can take some engine bay temps with and with out weather strip. it would be interesting to see what if any temp differentials.

I don't think it's as simple as that. First, it's not really engine bay temps that are our main concern. We want to get rid of heat from the hot coolant because that's what is overheating and ruining our track time. (And oil too, but the two are thermally connected.) In fact if we had a super good cooling system that efficiently dumped all the heat out through the radiator, the air in the engine bay would be super hot and yet the engine internally would run nice and stay at the right temperature. We care more about the inside of the engine where the heat is generated and the metal is many hundreds of degrees hotter than the outside of the engine block.

Let's talk about what we want for the best cooling function of the radiator. We want high pressure air in front of it, and low pressure behind it. For creating high pressure air, we have the blunt front end of the car going through the air and this is very effective. All we need is to make sure the grille is open enough to apply that high pressure zone of air to the radiator. The Civic grille has that big wide bar across it and so that's why the Ebay grille seems to work better. They do that because it lowers drag and it's fine for street driving. The grille itself will cause a pressure drop as the air passes through it. Each bar and strand of mesh leaves a small wake behind it and that reduces the high pressure before it gets to the radiator. There is also ducting that seals the sides of the radiator so that less air goes around and more goes through the fins. This is good.

Next we want to lower the pressure in the engine bay so that the air is pulled through the radiator fins. We have fans that pull air through the radiator by sucking it through. We have low pressure under the car and some air escapes down and around the undertray cover. Air also leaves through the fender vents, which are positioned in a low pressure zone. The same amount of air exits as enters, so if you open the front grille up, you will get better results by finding more exits for that air also.

Now as the video above showed, if we open up the back of the hood so that high pressure at the windshield is coming forward into the engine compartment, this is the opposite of what we want. The rubber seal is improving cooling if this is the case. We do not want to bring more air forward when it is going to fight the air that is trying to come through the radiator. I think hood louvers would help. Switching out the hood scoop for a vent or something like the Varis hood would help.

 

[Akuto]

I don't think it's as simple as that. First, it's not really engine bay temps that are our main concern. We want to get rid of heat from the hot coolant because that's what is overheating and ruining our track time. (And oil too, but the two are thermally connected.) In fact if we had a super good cooling system that efficiently dumped all the heat out through the radiator, the air in the engine bay would be super hot and yet the engine internally would run nice and stay at the right temperature. We care more about the inside of the engine where the heat is generated and the metal is many hundreds of degrees hotter than the outside of the engine block.

Let's talk about what we want for the best cooling function of the radiator. We want high pressure air in front of it, and low pressure behind it. For creating high pressure air, we have the blunt front end of the car going through the air and this is very effective. All we need is to make sure the grille is open enough to apply that high pressure zone of air to the radiator. The Civic grille has that big wide bar across it and so that's why the Ebay grille seems to work better. They do that because it lowers drag and it's fine for street driving. The grille itself will cause a pressure drop as the air passes through it. Each bar and strand of mesh leaves a small wake behind it and that reduces the high pressure before it gets to the radiator. There is also ducting that seals the sides of the radiator so that less air goes around and more goes through the fins. This is good.

Next we want to lower the pressure in the engine bay so that the air is pulled through the radiator fins. We have fans that pull air through the radiator by sucking it through. We have low pressure under the car and some air escapes down and around the undertray cover. Air also leaves through the fender vents, which are positioned in a low pressure zone. The same amount of air exits as enters, so if you open the front grille up, you will get better results by finding more exits for that air also.

Now as the video above showed, if we open up the back of the hood so that high pressure at the windshield is coming forward into the engine compartment, this is the opposite of what we want. The rubber seal is improving cooling if this is the case. We do not want to bring more air forward when it is going to fight the air that is trying to come through the radiator. I think hood louvers would help. Switching out the hood scoop for a vent or something like the Varis hood would help.

Yup, thats why I recommend the Trackspec louvers for those who dont want to buy a brand new hood and are ok with cutting the oem one

 

[Tim818]

PTP is about to release this, sits on top of the downpipe:

 

[Akuto]

PTP is about to release this, sits on top of the downpipe:

I thought PTP already had a downpipe blacket?

 

[Tim818]

I thought PTP already had a downpipe blacket?

They use to make a custom one for the grp downpipes, not sure if you can buy the blanket separately without buying the downpipe

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