Rb Engine Track Work Temp.

[SS8_Gohan]

A supercar will maintain 68deg for its sighting lap, 78deg sitting on the grid maybe rise to 80deg when the lights are on then drop to 68-70 for the entire race.

68-70 water temps for a V8 supercar in race conditions? that's impressive... and you're saying you can achieve similar with road cars in track conditions?

[GTSBoy]

Of course you can. It's just a combo of big enough radiator and decent airflow in and out. V8 Supercars have a reasonable undertray, at least part of which is aimed at getting the radiator exhaust airflow out of the engine bay properly.

Of course they are only having to deal with the waste heat from an X hundred HP engine, not also running an intercooler and air con condensor as extra heat loads out front, so that makes it a bit easier. All we have to do is work on sealing up the gaps around the sides so the air can only go through, etc etc.

[battery]

E85 dropped my average temp from 80-85 to 65-70, thats with the stock 76(or is it 78) degree thermostat and stock rad.

[scotty nm35]

I'm guessing your temp sensor is in the return flow back to the engine, after the radiator? Otherwise the minimum temps would be greater than the thermostat opening temp. (unless it is drilled or faulty)

My car saw 122 degrees water temp at Sandown on a 30 degree day, after only 3 laps. This is taken at the outlet of the head at the back of my VQ. If I measured the temperature at the radiator outlet it would be much lower obviously, and I wouldn't be so worried. I still have to try blocking the sides to force air through the coolers, that should help me. Otherwise I may have to resort to a water spray kit I guess.

Running 500hp on a 2.5L is going to generate much more heat than a 500hp NA 5L imo.

[battery]

I'm guessing your temp sensor is in the return flow back to the engine, after the radiator? Otherwise the minimum temps would be greater than the thermostat opening temp. (unless it is drilled or faulty)

Nope stock location, i have an aftermarket sensor/gauge and also the standard sensor which I read off the power FC. Seemed weird to me at first too, I thought the thermostat was faulty but I spoke to Trent and he reckons its normal?!?! Apprantly his laurel does the same thing.

Im changing the hoses soon so ill test in some water on the stove, seems crazy to think that the water is sitting stagnate and the oil system alone is cooling it.

[Dale FZ1]

E85 dropped my average temp from 80-85 to 65-70, thats with the stock 76(or is it 78) degree thermostat and stock rad.

Under what conditions? Presuming road use.

[Risking]

A V8 engine is designed to run at those temperature for extended periods, clearances and tunning is done to suit. It is possible to make an RB run at those temps but by design they are not ideal at those temperatures.

We dont run a thermostate, the coolant to the head is controlled and air bleeds are critical. The pumps speed is what ultimatly decides the coolant temperature.

Radiator ducting is paramount to the cooling systems effectivness. Without the front bumper and the couling they will over heat within a couple of laps.

Here is an intake recently done for a 180sx im building. It incorporates the intercooler obviously but has un upper cavity that provides fresh air to the radiator as well as radiated heat from the cooler.

Ill rip the bumper off a super car today and take a photo of the couling and what they use.

The undertray is nothing at all compared to what some people do with skylines.

They use a short tray to create a low pressure at the rear edge and assist drawing air away from the engine bay instead of trapping it in.

Splitter angle also effects the cooling system on a supercar, if they are set wrong it deflects air away from the intake duct and kills air flow over the radiator

[DVS JEZ]

Love seeing cars like that at ur shop. Makes me druel in jealousy

[bigmikespec]

A V8 engine is designed to run at those temperature for extended periods, clearances and tunning is done to suit. It is possible to make an RB run at those temps but by design they are not ideal at those temperatures.

We dont run a thermostate, the coolant to the head is controlled and air bleeds are critical. The pumps speed is what ultimatly decides the coolant temperature.

Radiator ducting is paramount to the cooling systems effectivness. Without the front bumper and the couling they will over heat within a couple of laps.

Here is an intake recently done for a 180sx im building. It incorporates the intercooler obviously but has un upper cavity that provides fresh air to the radiator as well as radiated heat from the cooler.

Ill rip the bumper off a super car today and take a photo of the couling and what they use.

The undertray is nothing at all compared to what some people do with skylines.

They use a short tray to create a low pressure at the rear edge and assist drawing air away from the engine bay instead of trapping it in.

Splitter angle also effects the cooling system on a supercar, if they are set wrong it deflects air away from the intake duct and kills air flow over the radiator

I worked with C&R Racing to come up with a radiator design that would adequately support 700hp and their issue was the frontal area was simply not enough. We did manage to get pretty close with a better core and kept all oil cooling separate from the radiator. Proof will be in testing... some time in 2013 I hope!

[Risking]

Love seeing cars like that at ur shop. Makes me druel in jealousy

I've got to have a chat with you shortly about tuning that car. It's off to paint shop next week than final assembly.

[DVS JEZ]

Sure thing mate. U have my number

[STATUS]

if setup correctly you should be able to lap continuously.... not cheap but its possible.

this 350rwkw car will lap in mid 30+ degree weather and stay under 95c even after 15 hot laps (last year he did a whole 25min session @100%... much to my amazment).

Normal operating temps are around 88c.

[ssxRicho]

...A supercar will maintain 68deg for its sighting lap, 78deg sitting on the grid maybe rise to 80deg when the lights are on then drop to 68-70 for the entire race...

The $1-1,500 radiator will have a little to do with that as well I would imagine. Over the ebay or even jap spec units we run.

Ducting to awesome btw. Like a lot!

[Risking]

The $1-1,500 radiator will have a little to do with that as well I would imagine. Over the ebay or even jap spec units we run.

Ducting to awesome btw. Like a lot!

The radiator core does make a difference to them. I had problems with a leaking end tank at the join once and replaced the core with an adrad as it was quicker to get it running again.

The bloody thing ran at 88deg all day long. Was still cool enough but the flow charactaristics of the adrad and PWR cores was different. I still think if we changed water pump pulleys and made it suit the adrad it would have been fine and back to normal.

The core is about $400 from PWR the money's in the end tank fabrication and they are about 80mm thick.

Thanks, there was a bit of work in the ducting. Ill take a photo of the inside. There is a divider plate that directs half the air over the intercooler and directly to the radiator, fresh air to the radiator is the absolute key.

[kitto]

Interesting thread. Some good posts.

What is the ideal way to set up a normal RB cooling system if money (within reason) isn't too much of an issue. This is for dedicated hard track use.

By normal setup i mean, Radiator in the factory position, using a 76 degree thermostat, oil cooler, intercooler in front of the radiator etc.

Reason i'm asking is this is another task for me to do in the future when my car goes back together. I'd like to set it up properly the first time.

My current plans are;

- PWR radiator (42 or 55mm available from memory)

- Swirl Pot - Still unsure about the best way to set this up with the optimal bleeding points and so on. I have bought a GReddy unit.

- Full ducting for the intercooler / radiator and the oil cooler

- I am trying very hard to try and keep the clutch fan and shroud set up, but this may not be possible due to space. A quality thermo fan and duct set up may have to be fitted

- I plan to delete the factory heater core as well - just trying to work out how to demist the windows if i delete it.

- Splash shield under the engine to draw the air past the engine and effectively out of the engine bay

What else can be looked at and done to set this up correctly?

[Risking]

PWR radiator cant go wrong.

Im not a fan of the japanese headertank setups, I do my own headers but just make you beed the top of the radiator, high points of the head and have a main filler on it.

Ducting has been said before, do it right and most importantly try to get fresh air over the intercooler and to the radiator.

You can do something very similar to what I posted above on the GTR.

I dont like mounting oil coolers inbetween radiators and intercoolers if its possible to mount them elsewhere. If you must put it there then I always run a dedicated duct for the oil cooler so its radiated heat cant dispurse into the air between the cooler and radiator. Have a rearward couling that forces the air out under the radiator from behind the oil cooler. ( i think that makes sence?)

If its track only get rid of the fan all together, seriously its unessisary if you have the cooling system set up properly for a track only car.

Undertrays etc just do your reasearch I dont feel they are important as the radiator ducting but they certainly have a place.

Buy an electric heated screen for window demisting. They work great but are pricey.

[kitto]

Yeah once i had bought the Greedy header tank i wasn't super impressed with it.

So basically your idea of a head tank is;

Header tank is the main fill point for the cooling system - Is this entirely necessary? Bottom of header tank to the pump inlet of the engine, Bleed points from the top of the radiator and two? from the highest point on the head to the top of the header tank. Header tank houses radiator cap with overflow connecting here.

Are you able to just fill the radiator as per normal, once that is full, start filling from the header tank?

Ducting i will be able to sort out fairly easy. Shouldn't be too hard. I had intended to fit the oil cooler in front of the intercooler. I changed my mind a while ago and think i'll be mounting it behind the RHS of the front bar.

As much as i'd like to get rid of the fan, i do like the idea of keeping one. It may adverse the amount of air that is able to travel into the radiator at high speed. But at low speed / pits etc i think i'll greatly benefit from having one there.

Of course an under tray is not as important as the frontal ducting. But it does help guide the air better out of the engine bay correct?

Yeah, unfortunately no one makes electric heated windscreens or electric stick on kits for an R31 front wind screen.

[STATUS]

Rb loves simple header tanks too. Be sure to tap into the correct areas for it to be effective. My laurel with std r34 clutch fan and smaller pwr rad will not go over 93.

[ARTZ]

whats the right areas to tap into ??

[White GTS-T]

Here's a pic of the peak values I recorded at a drift day at Winton in 30+ degree heat. Although the oil temp was creeping up a bit in the afternoon after continues hard laps due to not having to stop at the dummy grid, the brand new Federals were giving away before I would have to pit. Set up is as follows:

RB20 making 220rwkw

Trust front bumper.

GT-R bonnet and grill.

Custom bash tray/undertray

Radiator air diversion plate.

No A/C

Greddy tube and fin intercooler

Koyo 52mm radiator.

RB25 fan shroud.

Rb25 Neo clutch fan and hub.

Nismo radiator cap.

HKS oil cooler with re-locator kit mounted in the RHF bumper .

Edited January 4, 2013 by White GTS-T