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Hey all I have just purchased a an r34 sedan car has a 3076r with all supporting mods (fmic, inj, afm etc)

Also has a "heavy duty" radiator.....it has standard top tanks but core looks to be about 40 mm thick (standard is around 15mm)

when driving normaly the temp sit in the middle of the of the factory gauge (my other standard r34 sits in the same place)and the aftermarket gauge which is in the top radiator hose sits about 100 but when I drive it a little bit hard ie full boost a few times up to 100km or so it heats up to about 110 120t is this normal to have quite vast temp changes with such little hard driving or am I being paranoid?

Im only worried because my old silvia had a similar set up but ac was removed and had a thick koyo radiator temps never went above 90 on a 30 degree day no matter how hard I drove it

should I look at getting

transmission cooler

oil cooler

alloy radiator ?

any imput would be apprecated thanks Ben

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Transmission and oil cooler won't lower the water temperature...

100 seems rather high? My temp gauge sits at around 70-75 during everyday driving, doesn't make much difference what the outside temperature is. Gets maybe as high as 90 if I'm flogging it around. That's with a triple core alloy radiator though.

I've got a R33 with a 3076R and mine never gets that hot. It'll run around mid 80's to low 90's at the track on a 30+ degree day. All my cooling system is completly stock too. I would be looking at either the themostat, how far is it opening? The fan, not sure if 34's are still mechanical fans, but check your belt tension and fell how much air its blowing as the clutch on the fan may be not locking up. Biggest issue if it has a bigger rad is it using the cowling? If theres no cowling this can cause serious air flow issues and not draw enough air through the rad.

  On 05/04/2011 at 11:32 AM, ltcree said:

I've got a R33 with a 3076R and mine never gets that hot. It'll run around mid 80's to low 90's at the track on a 30+ degree day. All my cooling system is completly stock too. I would be looking at either the themostat, how far is it opening? The fan, not sure if 34's are still mechanical fans, but check your belt tension and fell how much air its blowing as the clutch on the fan may be not locking up. Biggest issue if it has a bigger rad is it using the cowling? If theres no cowling this can cause serious air flow issues and not draw enough air through the rad.

So should I give one of these a go? http://www.justjap.com/store/product.php?productid=16888&cat=&page=2

How do i tell if the fan is locking up I just had a look and it spins quite freely

You guys over there have stolen the good weather so no surprise something like this is coming up :)

Forget thermostats mate. Stock is fine.

What you need to do first is get the radiator out, give it a good flush and a refill with distilled water and so on. I believe you can get them flow tested too so this would be a good idea.

Also the FMIC could not really be flowing much air and blocking which will also cause issues.

If giving it a solid flush and so on does not work, then you'll need to invest in a decent radiator. By saying the one you have now looks as if it has stock header tanks, then i'd be dubious of it being aftermarket.

A decent 40-45mm ally radiator from somewhere like Race Radiators (a melb mob, just as an example)... Will almost certainly fix the issues.

HOWEVER don't go for the fix immediately, best to know what is the issue first.

  On 05/04/2011 at 10:35 AM, Hanaldo said:

Transmission and oil cooler won't lower the water temperature...

100 seems rather high? My temp gauge sits at around 70-75 during everyday driving, doesn't make much difference what the outside temperature is. Gets maybe as high as 90 if I'm flogging it around. That's with a triple core alloy radiator though.

Do you have a low-temp thermostat as well?

My experience with a stock R34 and brand new thermostat is that it sits pretty solid between 88C & 90C in most situations. The R34 thermostat doesn't open until 85C and fully open by 95C from what I recall.

My 2c =

Put a new thermostat (OEM) and a factory radiator in it. Im confident this will fix the issue.

As Ash said, intercoolers can be a problem. I had an older model JJR core on a car of mine a few years back and had all world of trouble.

  On 06/04/2011 at 2:17 AM, jrm said:

Do you have a low-temp thermostat as well?

My experience with a stock R34 and brand new thermostat is that it sits pretty solid between 88C & 90C in most situations. The R34 thermostat doesn't open until 85C and fully open by 95C from what I recall.

Stock Neo thermostats are 82deg

  On 06/04/2011 at 3:51 AM, GTScotT said:

My 2c =

Put a new thermostat (OEM) and a factory radiator in it. Im confident this will fix the issue.

As Ash said, intercoolers can be a problem. I had an older model JJR core on a car of mine a few years back and had all world of trouble.

Ditto, as I've said in other threads, I had a cheapo china radiator and while it was nice and thick, it used to heatsoak horribly, tossed it in favour of a GTR radiator and had no more dramas.

  On 06/04/2011 at 2:17 AM, jrm said:

Do you have a low-temp thermostat as well?

My experience with a stock R34 and brand new thermostat is that it sits pretty solid between 88C & 90C in most situations. The R34 thermostat doesn't open until 85C and fully open by 95C from what I recall.

It's stock as far as I know, I haven't put in anything aftermarket. Small chance that it has an aftermarket one in it from Japan but I wouldn't know for sure.

Your thermostat could be stuck/blocked, replace this first (it's the cheapest and easiest)

check-temps again

Replace the radiator with something that slides right in.

While you are at it replace all the water hoses. yep..ALL of them.

Have a beer and never worry again about over heating.

Hottest I've seen my car is 88掳C when driving in heavy traffic in 40掳 days(R33) but R34 will get a few degrees warmer.

Anything over 95掳 is too hot, ever.

Yeh 95 isn't that bad. With coolant and a properly pressurized system, you're no where near boiling point. I've seen my water temps hit 110 during a track day, have seen full on race cars reach as high as 160 degrees without damaging anything.

Anything over 95掳 is too hot, ever.

  On 07/04/2011 at 7:25 AM, bubba said:

No, it's not.

Maybe EVER was too strong a word. If you get above 95掳 simply by doing a few 0 -100 sprints then you have a problem and need to address it.

The R34 was designed as a slightly higher temp RB25 than the R32/R33 for efficiency.

Increasing the coolant temp ~10掳C roughly doubles the pitting and deposit formation and therefore results in faster wear on water pump impellers, heater cores, dissimilar metals, etc. People may think high temps haven't damaged anything simply because nothing has broken immediately, but parts in the cooling system and gaskets get damaged.

Edited by simpletool
  On 07/04/2011 at 8:03 AM, simpletool said:

Anything over 95掳 is too hot, ever.

Maybe EVER was too strong a word. If you get above 95掳 simply by doing a few 0 -100 sprints then you have a problem and need to address it.

The R34 was designed as a slightly higher temp RB25 than the R32/R33 for efficiency.

Increasing the coolant temp ~10掳C roughly doubles the pitting and deposit formation and therefore results in faster wear on water pump impellers, heater cores, dissimilar metals, etc. People may think high temps haven't damaged anything simply because nothing has broken immediately, but parts in the cooling system and gaskets get damaged.

Isn't it every 10 degrees over the maximum coolant operating temperature halves the engine life expectancy? Not sure what that maximum temperature is on an R34, but it would surely be much higher than standard water boiling point.

  On 07/04/2011 at 8:03 AM, simpletool said:

Anything over 95掳 is too hot, ever.

Maybe EVER was too strong a word. If you get above 95掳 simply by doing a few 0 -100 sprints then you have a problem and need to address it.

The R34 was designed as a slightly higher temp RB25 than the R32/R33 for efficiency.

Increasing the coolant temp ~10掳C roughly doubles the pitting and deposit formation and therefore results in faster wear on water pump impellers, heater cores, dissimilar metals, etc. People may think high temps haven't damaged anything simply because nothing has broken immediately, but parts in the cooling system and gaskets get damaged.

Do you have evidence to back up your scaremongering?

I agree that if you're reaching 95deg after a couple of hard jaunts up to 100kmh there is an issue that likely needs to be addressed.

Telling people that reaching 95deg is OMG GOING TO REDUCE THE LIFE OF EVERYTHING THE COOLANT TOUCHES, is scaremongering.

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