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Noticed yesterday driving home on the highway, that my water temp was just shy of the second line, right before the H line (aka bloody hot) and the oil temp sitting just at half.

Has been really warm in Victoria here, but I've done a little research and was just looking for a few opinions:

1. Looking at replacing the thermostat first as I know the car had its 100k timing belt/water pump done from the previous owner - is there a specific thermostat I should be using? Part number would be great.

2. Having the radiator completely flushed, cleaned and replacing the thermostat professionally (hence wanting them to fit the right one) - how much does a flush usually cost?

I have recently fitted a POD (Apexi Power Intake) and am waiting on my cold alloy housing, so is the POD sucking in hot air also a contributing factor or no?

If there's anything else I'm missing here, fill me in. Driving a R34 GTT 2001, basically stock.

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Hey Mike,

First search on google for "r34 gtt thermostat part number" came up with: Part number for R34 GTT 82degree thermostat should be 21200-V7205 - and that is from SAU

Having PODS fitted shouldn't make your radiator non-existant. Most likely its either of three things: thermostat, waterpump or the radiator.

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Hey Mike,

First search on google for "r34 gtt thermostat part number" came up with: Part number for R34 GTT 82degree thermostat should be 21200-V7205 - and that is from SAU

Having PODS fitted shouldn't make your radiator non-existant. Most likely its either of three things: thermostat, waterpump or the radiator.

Yeah, I found this one just now from Kudos http://www.kudosmotorsports.com/catalog/coolant-thermostat-nissan-skyline-25gt-25gt-25gt-rb25de-rb25det-p-423.html which should be fine.

Just didn't know if most just went to supercheap (I fu&@$ing hate supercheap) and grabbed a generic one.

What's a typical price for a flush would you know? I'm not an expert, but I'm not a beginner, just don't want to get ripped. Expecting 100-120?

My advice when getting a thermostat is to get one that doesn't use a rubber seal around the valve. I think the genuine Nissan ones do and I had one in my car. When I changed it I found that the rubber seal around the valve was dislodged and holding the valve partially open all the time. The result was the car running 15 degrees cooler than normal operating temp. It was like having a Nismo thermostat which is not ideal for most road cars.

Go to Super Cheap or Repco and take the old one to make sure they measure the dimensions and temp rating and pick a new one without any rubber parts on it. I think I ended up with a Tridon or similar after market one that is all metal construction.

Now I'm torn between getting a flush and thermostat vs just getting a new radiator.

Stock rad has been fine for me ever since I've owned the car. Worried money from the flush/Thermo could just be going to a new rad

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Make sure you get a thermostat that opens up at 76 degrees.. not the R34 GT-t one which opens up like at 82 degrees or so.

Then invest in an eBay radiator, the likes of ASI or Worley work perfectly fine (better than stock) on a street and light track car.

Now I'm torn between getting a flush and thermostat vs just getting a new radiator.

Stock rad has been fine for me ever since I've owned the car. Worried money from the flush/Thermo could just be going to a new rad

Your stock radiator is around 10 years old.......those cores only last a certain time, 10 years is about it for efficiency. A new radiator is a definite plus IMO.

Standard Japanese radiators are anorexic.

I suppose they weren't really tailor made for the Australian climate huh.

All in all, SAU has taught me that buying parts from eBay is a bad time, apart from radiators? If anyone can reccomended a decent one, doesn't need to be race quality, that'd be cool (pun intended!).

I had Splitfires basically forced down my throat when I was looking at coils and that turned out really well so I trust you guys, you hear.

ASI or Worley direct

then make sure you file down the sensor bung for the overheat thermofan and you'll be sweet.

Don't go more than 43mm if you want to run your stock shroud without it collecting your fan blades at high RPM

I had my Cooling Pro cleaned a few months back for $150. Justjap were out of stock at the time, and the radiator dude said that unlike most of the chinese crap he sees the Cooling Pro was decent. Price on the R32 one is now only $239 - was ~$320 when i bought mine. So yeah, agree you should get a new one.

Bit of an update: cruising home, around 28, driver beside me on the highway being a bit of a tool, overtaking me and matching speed so I peg it in front of him, take it to 170.

Shortly after my water temp again went up to the high line. I dunno why, but I figured if it's thermostat related, I'll crank on the heater on full.

Sure enough it started to drop eventual to the halfway mark. Can someone explain why or just a coincidence?

Make sure you get a thermostat that opens up at 76 degrees.. not the R34 GT-t one which opens up like at 82 degrees or so.

Why? This is silly. The GTT is designed to run at 82 degrees, not 76 degrees.

Temp gauge going up to H means you are seeing 110 degrees water temp. Something is seriously wrong, either your water pump is f**ked, your radiator is blocked, or the thermostat is broken and only partially opening.

I have the stock rad and thermostat in my GTT, giving it arseholes around Eastern Creek and the actual water temp gradually crept up from 85 degrees normal operating up to 100 degrees after about 8 hard laps. Never went higher than 100 and the stock gauge was still showing half way ie normal.

If you are seeing hotter temps because you've upgraded your engine power levels the first step is a thicker radiator. Keep the thermostat standard, the radiator is what gets rid of your waste heat. A bigger one will do that job better. Stable temps are better for your engine, the way to get this is with the correct thermostat for your engine and a big enough radiator to get rid of the heat load you're putting into it.

Why? This is silly. The GTT is designed to run at 82 degrees, not 76 degrees.

Temp gauge going up to H means you are seeing 110 degrees water temp. Something is seriously wrong, either your water pump is f**ked, your radiator is blocked, or the thermostat is broken and only partially opening.

I have the stock rad and thermostat in my GTT, giving it arseholes around Eastern Creek and the actual water temp gradually crept up from 85 degrees normal operating up to 100 degrees after about 8 hard laps. Never went higher than 100 and the stock gauge was still showing half way ie normal.

If you are seeing hotter temps because you've upgraded your engine power levels the first step is a thicker radiator. Keep the thermostat standard, the radiator is what gets rid of your waste heat. A bigger one will do that job better. Stable temps are better for your engine, the way to get this is with the correct thermostat for your engine and a big enough radiator to get rid of the heat load you're putting into it.

Far by the beat advice I've received to date on any post I've made.

Only mods I've made are a currently unshielded pod Apexi power intake and Splitfire coils, so I'm leaning towards the thermostat or just the radiator in general. I know the pump was replaced at 100k, and I'm almost at 160k, so should still be good.

Been advised to hell and back as you can see to replace the radiator so was going to do the thermostat at the same time, but if it isn't the radiator, is it really worth upgrading I.e if it ain't broke don't fix it

Why? This is silly. The GTT is designed to run at 82 degrees, not 76 degrees.

Temp gauge going up to H means you are seeing 110 degrees water temp. Something is seriously wrong, either your water pump is f**ked, your radiator is blocked, or the thermostat is broken and only partially opening.

I have the stock rad and thermostat in my GTT, giving it arseholes around Eastern Creek and the actual water temp gradually crept up from 85 degrees normal operating up to 100 degrees after about 8 hard laps. Never went higher than 100 and the stock gauge was still showing half way ie normal.

If you are seeing hotter temps because you've upgraded your engine power levels the first step is a thicker radiator. Keep the thermostat standard, the radiator is what gets rid of your waste heat. A bigger one will do that job better. Stable temps are better for your engine, the way to get this is with the correct thermostat for your engine and a big enough radiator to get rid of the heat load you're putting into it.

how is it silly? you now have more head room.. most fuel compensation tables stop adding in fuel after 60 or so degrees... I will double check tonight for NEO motors when I'm home and on my laptop with Nistune open.

Better to have a wider range instead having only 20 degrees of movement before water starts to boil (yes throwing arbitrary numbers and not factoring in coolant and higher pressure raises the boiling point of water/coolant mix)

Even though the thermostat opens at 82, by the time you read and what not it's already close to 90 degrees.

Each to their own I suppose. To end this higher operating temps were mainly for emissions, economy and thus engine efficiency.

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