Radiator Suggestions

[iruvyouskyrine]

Hi all, looking for a decent radiator to chuck in my R32. I would like one that lets me retain the standard radiator shroud and doesn't cost me ridiculous amounts of money. Running a 52mm ebay special and would like to drop down to a ~42mm one so i can keep the shroud.

300+kw RB25DET Neo running ~20psi gets very hot on track. Was maybe 30deg ambient temp and was sitting around 92 at idle and got over 100 after 2-3 laps so i did cool down laps until it was back at low 90's. I am running a GKtech clutch fan also.

Any advice welcome, thanks!

[iruvyouskyrine]

Should note those figures are running with no bonnet or front bar, it was a good 5-6deg hotter with the bonnet on.

[scotty nm35]

100 degrees or more is fine for a hot day imo. You will probably find the track temp is 40+ so the radiator was doing a fairly good job. Getting the shroud back on should be a priority though, can you get something fabricated in alloy perhaps?

[Dose Pipe Sutututu]

RB25DET NEOs run 90 degree thermostats, see if you can fit a 80 degree one.. also check with Trent if he has mad any fuel corrections at 80 degrees, if he hasn't go for it

I bought the wrong thermostat and my car also sits at 90 degrees.. I'm using a dim sim 43mm radiator and on the track I don't go over 110 degrees with the water

[KiwiRS4T]

RB25DET NEOs run 90 degree thermostats, see if you can fit a 80 degree one.. also check with Trent if he has mad any fuel corrections at 80 degrees, if he hasn't go for it

I bought the wrong thermostat and my car also sits at 90 degrees.. I'm using a dim sim 43mm radiator and on the track I don't go over 110 degrees with the water

Changing the thermostat will make no difference whatsoever to track temps!

[Dose Pipe Sutututu]

Changing the thermostat will make no difference whatsoever to track temps!

I guess so, however what I was trying to get at is say at normal operating temps your car runs at 80 degrees, and then you bash it around the track you have more headroom before you hit say 120 degrees, where as if you're running a 90 degree thermostat you having less headroom.

I'm happy to stand corrected

[iruvyouskyrine]

I knew Neos ran hotter (to meet more stringent emissions standards?) than standard 25 but I still thought 110deg was excessive. Ideally I would like to keep it around 100 but if that is unreasonable without a huge cooling set up then ill just take reasonable steps to keep it down and monitor it.

So anything under say, 115 deg is fine while thrashing it around the track?

The other thing I was slightly worries about is how hot the intake plenum gets, I know it has coolant flow through the neck of it but it gets very hot, to the point of burning you hand if you leave it longer than a second. This is after a gentle 20 min cruise doing 100 on the highway.

[gotRICE?]

I had similar issues with my R33 runnning a GT30 and a 52mm ebay radiator. Although mine fit with the shroud.

Day to day it was the same, but on track i was only gettin 2-3 laps if i was lucky and hitting 100+ too.

I think the issue is having the inlet/outlet on the same side of the radiator. If you go too big with the water tubes i think the water drops through the radiator too quickly, and doesnt efficiently use the whole surface area of the core.

I always intended on moving the outlet to the opposite end and turning it into a Tri pass.

[jay-rod]

I knew Neos ran hotter (to meet more stringent emissions standards?) than standard 25 but I still thought 110deg was excessive. Ideally I would like to keep it around 100 but if that is unreasonable without a huge cooling set up then ill just take reasonable steps to keep it down and monitor it.

So anything under say, 115 deg is fine while thrashing it around the track?

The other thing I was slightly worries about is how hot the intake plenum gets, I know it has coolant flow through the neck of it but it gets very hot, to the point of burning you hand if you leave it longer than a second. This is after a gentle 20 min cruise doing 100 on the highway.

Anything 110 or under is usually fine.

My Neo topped out around 108-109 after about 5 hard hard laps. That is Without a shroud, Stock clutch fan.

I have wrapped all my intake/crossover pipe/intercooler piping in exhaust wrap, this was the best thing i did as i no longer get Heat soak.

[75coupe]

Wow and i was worried about 104 after 7 laps around mallala on a warm day, but im a non neo...

[34GeeTeeTee]

Hi all, looking for a decent radiator to chuck in my R32. I would like one that lets me retain the standard radiator shroud and doesn't cost me ridiculous amounts of money. Running a 52mm ebay special and would like to drop down to a ~42mm one so i can keep the shroud.

300+kw RB25DET Neo running ~20psi gets very hot on track. Was maybe 30deg ambient temp and was sitting around 92 at idle and got over 100 after 2-3 laps so i did cool down laps until it was back at low 90's. I am running a GKtech clutch fan also.

Any advice welcome, thanks!

I'm going to guess THIS is your problem not the radiator itself.... I have run a Triple Pass RacePace radiator and had no temp issues on hot days and texis etc... The minute i changed to the GKTECH fan i was overheating in 4-5 laps of EC.... I am going to swap back to stock fan and run again on the 26th, ill update my build thread with the results...

[Dose Pipe Sutututu]

I'm going to guess THIS is your problem not the radiator itself.... I have run a Triple Pass RacePace radiator and had no temp issues on hot days and texis etc... The minute i changed to the GKTECH fan i was overheating in 4-5 laps of EC.... I am going to swap back to stock fan and run again on the 26th, ill update my build thread with the results...

good to see some hard facts

then again the stock fan blades are larger, in terms of surface area so you would think it will/would move more air than a smaller fan.

[iruvyouskyrine]

Interesting. I do have a stock fan still sitting here, so may see how the GKtech one goes and if it's no good ill swap it for the stocker and see if it makes a difference.

I'm doing winton drift matsuri this weekend and i will be taking 2 radiators, 2 clutch fans and a set of twin thermos. Surely that is enough to keep it cool? hahaha

[Dose Pipe Sutututu]

^ just in case some dim sims go exploding LOL

I got a mate who insisted that GK Tech fans were awesome sauce (S15 owner duh!) so he invested in their fan, and radiator.. guess what? his water temps are now higher than his stock setup.. lol

he's going to wakefield with me next month, probably wise to bring along the stock rad & fan too lol

[34GeeTeeTee]

Interesting. I do have a stock fan still sitting here, so may see how the GKtech one goes and if it's no good ill swap it for the stocker and see if it makes a difference.

I'm doing winton drift matsuri this weekend and i will be taking 2 radiators, 2 clutch fans and a set of twin thermos. Surely that is enough to keep it cool? hahaha

Ill be swapping it off as my car is getting hot at idle and high speed yet not at cruise (I did 500kms on a hot day with no prob at all) so it really does lean towards the fan issue... The stock fan should pull more than enough air! I guess i swapped the the GKTECH as it was black and suited my engine bay but it will now get removed for a comparison!

I could be wrong, but pretty sure the fan is the main issue!

^ just in case some dim sims go exploding LOL

I got a mate who insisted that GK Tech fans were awesome sauce (S15 owner duh!) so he invested in their fan, and radiator.. guess what? his water temps are now higher than his stock setup.. lol

he's going to wakefield with me next month, probably wise to bring along the stock rad & fan too lol

Well on that note, the SR seems to respond REALLY well to the fans and there are plenty using them with great success, for some reason the RB setup does not seem to favour the fans! There is another thread on them where people are going back to stock... It is interesting!

I would suggest your mate with the S15 bleeds his cooling system properly and makes sure everything is working properly as the SR generally goes good with it!

[Dale FZ1]

Retaining the OEM under-engine splash tray goes a long way to helping maintain airflow through the radiator core at higher speeds. There has to be a pressure differential across the core before airflow takes the heat away.

[Daleo]

Ill be swapping it off as my car is getting hot at idle and high speed yet not at cruise (I did 500kms on a hot day with no prob at all) so it really does lean towards the fan issue... The stock fan should pull more than enough air! I guess i swapped the the GKTECH as it was black and suited my engine bay but it will now get removed for a comparison!

I could be wrong, but pretty sure the fan is the main issue!

I see the same gradual loss of temp control at low speed on my VQ25det using a GKTECH fan; once moving temps come down very quickly.

It could be running in the low 80's (Nismo thermostat and a large 2 core alloy rad with factory shroud) and slowly creep up until it is into the low 100's, then once back above 70km/h temps will drop straight back to low 80's again. Also sound like a bloody aircraft taking off; which I hate.

Fortunately I only paid $20 for mine (when they were selling pre-orders) so I won't be too upset to chalk it up to experience...

I don't think it is a coincidence Matt.

[34GeeTeeTee]

This was something i was also going to try! Thanks for the input Dale!!!

Retaining the OEM under-engine splash tray goes a long way to helping maintain airflow through the radiator core at higher speeds. There has to be a pressure differential across the core before airflow takes the heat away.

I see the same gradual loss of temp control at low speed on my VQ25det using a GKTECH fan; once moving temps come down very quickly.

It could be running in the low 80's (Nismo thermostat and a large 2 core alloy rad with factory shroud) and slowly creep up until it is into the low 100's, then once back above 70km/h temps will drop straight back to low 80's again. Also sound like a bloody aircraft taking off; which I hate.
Fortunately I only paid $20 for mine (when they were selling pre-orders) so I won't be too upset to chalk it up to experience...

I don't think it is a coincidence Matt.

Nice to know! Well not nice but good to see its not just me blaming the fan! Amazing how it just doesn't work for our engines yet SR's love them!

On that note, mine is quiet, most complain about the noise but i didn't really have that issue... Maybe i should buy a fan hub too just to be safe?

[Dose Pipe Sutututu]

Well on that note, the SR seems to respond REALLY well to the fans and there are plenty using them with great success, for some reason the RB setup does not seem to favour the fans! There is another thread on them where people are going back to stock... It is interesting!

I would suggest your mate with the S15 bleeds his cooling system properly and makes sure everything is working properly as the SR generally goes good with it!

yeah I'll give that a crack, I told him not to buy it but he's a GK Tech fan boy so he bought it along with a bunch of their suspension arms, after I specifically told him ONLY to buy the rear camber arms LOL

[34GeeTeeTee]

yeah I'll give that a crack, I told him not to buy it but he's a GK Tech fan boy so he bought it along with a bunch of their suspension arms, after I specifically told him ONLY to buy the rear camber arms LOL

I have the front castor arms, im a bit of a fan of them compared to the other shit Chinese ones i had lol