M35 Stagea Replacement Radiator

[Mattl2]

Hi, this is my first post on these forums but I have been driving a blue ARX for a bit over a year & have found plenty of usefull information on here already. Anyway a few days ago I had my top radiator tank split next to the fill cap as as happened to a few other owners going by the posts I found. I ordered the following radiator from ebay a few days ago expecting it to fit with a bit of cutting etc but after dusting off the dremmel I have just bolted it in with everything fitting back on perfectly with no modifications or cutting needed. Even the fan shroud fitted straight back on. It has the built in transmission cooler like the stock radiator too.

http://www.ebay.com.au/itm/220872242160?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649

It's a Koyo radiator part number RA1305AL. The service from the ebay seller was also great with it arriving on my doorstep the day after ordering & it only cost $330 delivered. Cheers, Matt.

[Commsman]

Hi Matt,

Thanks, I've saved that seller, just in case. That was very helpful for your first post .

[prince_skyline]

I bought the same Koyo one just a couple of weeks ago (same model number) - direct V35 Skyline replacement with no modifications required

Bought it from Radiator Centre for $238.70 delivered . This is online price with free delivery nationwide. Mine was delivered next day!

https://www.radiatorcentre.com.au/

https://www.radiatorcentre.com.au/radiators?body=350GT+Coupe+2d&id=9005&make=Nissan&model=Skyline&model_code=V35&transmission_type=Auto&year_range=2001+-+2008

Edited December 1, 2011 by prince_skyline

[prince_skyline]

Forgot to say........Welcome Matt!!!

Edited December 1, 2011 by prince_skyline

[zei20l]

my all alloy radiator was about $220 + delivery from china.......

[Commsman]

Way to make Matt feel bad for spending a few bucks more than he needed too, Doh!

It's ok tho, I reckon there's no one on here that hasn't found the same or equivalent part cheaper afterwards, at least once.

[bigkevracer]

I think if Matt found one that fitted without modding that's a win.

IIRC Iain's fit after he'd cut half the front end apart...

[zei20l]

the V35 radiator for 3.5L will need cutting anyway, its not that much. the 2.5L will bolt in fine

sorry, i should have mentioned that there is a whole thread for this radiator issue

however, that price is still decent for an OEM part!! the factory radiators on IM for M35 are still over $3250 + delivery + taxes blah blah, probably $600 by the time it gets here

[Mattl2]

the V35 radiator for 3.5L will need cutting anyway, its not that much. the 2.5L will bolt in fine

sorry, i should have mentioned that there is a whole thread for this radiator issue

however, that price is still decent for an OEM part!! the factory radiators on IM for M35 are still over $3250 + delivery + taxes blah blah, probably $600 by the time it gets here

The radiator I bought was listed as being for a 3.5L V35 & it bolted straight in. That's why I posted this thread as all the previous threads on M35 radiators said you would have to do some cutting to fit a 3.5l V35 radiator. Maybe it's just the Koyo 3.5L that is a direct fit. I looked for a 2.5L one first but could not find any for sale in Australia. I guessed somone would have the same radiator cheaper but I needed one asap & ebay is just about the only place I could order a radiator at 10pm & have it delivered to my house the following morning. Cheers, Matt.

[Daleo]

I've been looking at all of these single core replacements, has anyone seen a 2 core replacement in Aus?

Also a little off topic; what kind of temperatures are people seeing on OEM style radiators? I mean actual temps; not just where the needle sits. Possibly a question for Informeter users.

I'm seeing low to mid 90s with the air con on with 30 deg ambient temp. But if I give it a hiding; I can push it over 100 deg. It does recover, but I'd like to see it lower; maybe peaking in the low 90's, as I can see it struggling once we get some hotter weather.

I had my Informeter in last summer and I remember hitting 104 once, on an extremely hot day; but I'm talking low 40's.

[scotty nm35]

I still find the temps on the big Mishimoto to be around the same as your oem one, I may have to put the low temp thermostat back in once the Fcon is tuned as I really dont like seeing over 100.

And lucky you dont have the oil temp sender hooked up Dale, 120 degrees comes up very quick after a squirt even with the oil cooler.

[whitestag]

If I baby it from cold it likes 84-88. Hot day normal driving 90-93. Ac puts it 95-96 ish and hills push it up depending on how steep and how long. Highest I've had was 107 going up the steep hill on way up Newcastle in traffic. Decided old PAC would be better for both us lol.

I only worry if it's going over 97-98. As I been told by a few that it can handle till 110 or so before you asking for trouble.

[zei20l]

i hit 112 a few weeks ago on that really hot day in sydney, i had the AC on. which i turned off once it got that hot.

need to get that 54mm radiator in

[Daleo]

Ok, thanks for the feedback guys; sounds like I'm in the "normal range" then, thought I might have needed a new rad sooner than later.

Gives me time to first try a lower temp Nismo thermostat, and look into a slightly thicker core, there are some good options around that shouldn't break the bank, so I can do that when it suits.

It is interesting, my GSXR1000 runs around 86deg, but will go to 107deg before the thermo even switches on, and at the track it; routinely sees 104deg on the in lap after a session. This is very similar to my last bike (CBR929) I rode it with a pillion, for 5 hours, in 46deg heat with the gauge on 106deg the whole time and I had no issues on the day, or in the 5 years I owned it.

If you're seeing the same kind of temps with the big mutha rad in yours Scotty, in addition to an oil cooler; Perhaps our prevailing attitudes on cooling systems need a bit of a rethink?

Because for all the variation in temp, the needle barely moves; like not even half a graduation! This makes me wonder if these kind of temps are to be considered normal; at least from a manufacturers point of view. I mean if 104deg was a disaster; I'd expect the gauge to give a little warning? Sustained high temp are a no, no for sure; but maybe we need to revise our understanding of the "normal" range?

I think I'm going to reset my Informeter warning alarm at 104 which is my current high point.

Perhaps ignorance truly is bliss...

[slippylotion]

Manufacturers don't make the temp gauges very sensitive to temp fluctuation for a reason. If it moved an increment for every degre temp increase owners would straight on the phone complaint their car is overheating.

I'm keen to find out if there is an affordable twin core option available rather than the stocking 16mm core.

Edited December 3, 2011 by slippylotion

[Daleo]

Manufacturers don't make the temp gauges very sensitive to temp fluctuation for a reason. If it moved an increment for every degre temp increase owners would straight on the phone complaint their car is overheating.

I'm keen to find out if there is an affordable twin core option available rather than the stocking 16mm core.

That's sort of my point; but if the gauge didn't move, and then spontaneously overheated, I'd reckon there would be a few calls too. There will always be an "acceptable range" we are likely to be operating within it; but making judgements based on cars we've owned prior.

I'd still like to see the car going nothing over 100deg; regardless of ambient, as Scotty said.

Koyo do a 36mm dual core version of their plastic end tanked V35 radiator; I think this will be a viable option; but I'm not sure if it has the heat exchanger in the bottom tank (not that it bothers me). Inlet, outlet and Rad cap are in the oem positions. I'd imagine there will be some trimming required; but virtually everything except direct replacement will.

I'd like to do that rather than go to the "Full Race" spec 52mm cores; I think they can end up actually restricting airflow through the core. You see this particularly in the R32-R34's (particularly GTR's) with generic 52mm all alloy aftermarket rads. Go back to an OEM; all good.

The 36mm Koyo is readily available in the US; I haven't looked locally, but a Koyorad distributor should be able to get it.

[zei20l]

when mine hit 112 the needle was over the halfway mark, normally it sits a little below the halfway mark

AFAIK all VQ radiators have the inlet and outlet in the right position, the radiator cap may not be. Z33s have them in a different position.

[PN-Mad]

Just to add my 2 cents, I think that the big core rads are a bit of a trick. I've heard that sometimes they are so big, and non restrictive that the coolant can pass right through them without being in them long enough to have a cooling effect. That is why the expensive big brands have a two, or even three pass system.Hence why you see cars with big rads still overheating.

[Daleo]

when mine hit 112 the needle was over the halfway mark, normally it sits a little below the halfway mark

AFAIK all VQ radiators have the inlet and outlet in the right position, the radiator cap may not be. Z33s have them in a different position.

Yeah; so the gauge defintitely does provide some feedback, if you pay attention. The one I've been looking at has the rad cap in the right spot.

Just to add my 2 cents, I think that the big core rads are a bit of a trick. I've heard that sometimes they are so big, and non restrictive that the coolant can pass right through them without being in them long enough to have a cooling effect. That is why the expensive big brands have a two, or even three pass system.Hence why you see cars with big rads still overheating.

I think you're right Alex, most aftermarket cores use much thicker wall, larger bore tube; mainly because it's cheaper, and easier to work with; which also has the effect of leaving a lot of laminar flow in the tubes.

The laminar flow is basically dead water in contact with the radiator tubes that doesn't really move, while a moving column of water runs down the middle. This minimises the cooling efficiency of the effectively larger core because most of the water isn't coming into contact with the wall; shedding its heat.

The thinner tubes in OEM radiators promote turbulent flow; the water effectively tumbles along the tube getting the maximum amount of contact with the wall of the tube; which maximises any cooling effect.

Also, using thinner tubes allows you to fit more tube surface area into a thinner core, which flows more air.

[scotty nm35]

Mine is at least twin pass as one end of the top tank was cold and the other hot when I checked, just after the thermostat opened.

The other thing to remember, my cooling system now holds twice the water which is another can of worms.