MR2 Roadster Owners Club

I have seen water temps creep up steadily on closed/slow track, so I'd like to upgrade my cooling system. Easy you say, there's at least two performance radiators available: Mishimoto (52mm core, quality?) and Koyo KL010929R (53mm core).

I have another condition though: I want to keep my A/C. And this is where it gets complicated.

I haven't found much data on if mentioned performance radiators work together with A/C condenser, as they're a lot beefier (read somewhere Mishimoto requires cutting slam panel too).

So I need some help from first hand: is anyone running one of those together with A/C? Any slam panel cutting necessary?

Also, are there any alternatives I have missed?

Cheers!

Bonnet scoop and ducting to help pull the air through the radiators and reduce resistance?
If it's also a daily, can always have a 2nd bonnet with the scoop. If it's just for track it can be any old colour and in whatever state. Peanuts from any breaker.

What state is your current rad in?
When did you last change coolant?
How is your water pump?

I've never track driven a 2 but I ran an SP240 kit with a water cooled turbo and it never had any issues with cooling.

Quote from: 1979scotte on January 31, 2021, 17:29What state is your current rad in?
When did you last change coolant?
How is your water pump?

I've never track driven a 2 but I ran an SP240 kit with a water cooled turbo and it never had any issues with cooling.

Forgot to mention it's 2zz with limiter at 8600, and on slow tracks (less flow) and keeping it in high revs makes it even hotter. Higher speed tracks there's no issue that I recall of.

Water pump was changed 4-5 years ago, fluid 2 years ago. Rad is original but no leaks.

Quote from: shnazzle on January 31, 2021, 17:27Bonnet scoop and ducting to help pull the air through the radiators and reduce resistance?
If it's also a daily, can always have a 2nd bonnet with the scoop. If it's just for track it can be any old colour and in whatever state. Peanuts from any breaker.

Interesting idea! If it was full track toy then I'd go ahead, but I want to keep it road friendly and keep the frunk too.

Quote from: inside on January 31, 2021, 17:50

Quote from: shnazzle on January 31, 2021, 17:27Bonnet scoop and ducting to help pull the air through the radiators and reduce resistance?
If it's also a daily, can always have a 2nd bonnet with the scoop. If it's just for track it can be any old colour and in whatever state. Peanuts from any breaker.

Interesting idea! If it was full track toy then I'd go ahead, but I want to keep it road friendly and keep the frunk too.

As I said, track bonnet with the ducting built into it. Then all you need to do is remove the frunk bin and put the track bonnet on

Quote from: inside on January 31, 2021, 17:49

Quote from: 1979scotte on January 31, 2021, 17:29What state is your current rad in?
When did you last change coolant?
How is your water pump?

I've never track driven a 2 but I ran an SP240 kit with a water cooled turbo and it never had any issues with cooling.

Forgot to mention it's 2zz with limiter at 8600, and on slow tracks (less flow) and keeping it in high revs makes it even hotter. Higher speed tracks there's no issue that I recall of.

Water pump was changed 4-5 years ago, fluid 2 years ago. Rad is original but no leaks.

I would buy a cool parts rad from ebay and see if that makes a difference they are so cheap.

I have a Japan parts on the V6 and it wasn't a straight fit even though it was for a zzw30.

I don't remember ever hearing anybody with a 2zz complaining of high temps on track.

Last time I had temp issues it ultimately turned out to be head gasket.

Also don't forget your oil. An oil cooler can also bring those temps down on track. 
If I were tracking a car frequently I'd consider it a must have

Quote from: shnazzle on January 31, 2021, 18:39Also don't forget your oil. An oil cooler can also bring those temps down on track.
If I were tracking a car frequently I'd consider it a must have

I have oil cooler and it works a treat! Just water is creeping up.

Oh and not only do I have a bigger rad than stock I have a charge cooler radiator too so I can't see you not being able to make it all fit even if you have to fab some brackets up or something.

 I do not know the kind of thermostats our cars use but I did hear of thermostats only partially opening up that exhibits the same behavior of creep when the engine is stressed otherwise this shouldn't happen as our cooling systems are quite robust with some using the factory radiator for other engine swaps with larger displacements.

You're not running a standalone ecu are you?
As said above, overheating is not something we see often.
If you are running a standalone or some kind of modification that is causing the car to run lean, that may be causing temperature to increase.
Just as an example, when I ran my piggyback leaner I would often get to 93-94deg. When I switched back, it would never go beyond 91.

Worth trying a low-temp thermostat?

Sard are the usual go-to on the 4EFTE but I've just brought in a Billion one for one of my own builds.

Quote from: shnazzle on February  1, 2021, 07:42You're not running a standalone ecu are you?
As said above, overheating is not something we see often.
If you are running a standalone or some kind of modification that is causing the car to run lean, that may be causing temperature to increase.
Just as an example, when I ran my piggyback leaner I would often get to 93-94deg. When I switched back, it would never go beyond 91.

Yes ecumaster with wideband. It is running a bit leaner because stock was very rich. It also runs higher revs and lower lift point, imho the revs contribute a lot too. I didn't have this creep on stock ecu... But then again, I don't have the issue on higher speed track.

Quote from: Jay on February  1, 2021, 09:44Worth trying a low-temp thermostat?

Sard are the usual go-to on the 4EFTE but I've just brought in a Billion one for one of my own builds.

I thought about it, but I feel like it's just a band aid. I'd rather have better cooling capacity that engages later, so the temperatures are better during daily use too.

Quote from: 1979scotte on January 31, 2021, 18:23

Quote from: inside on January 31, 2021, 17:49

Quote from: 1979scotte on January 31, 2021, 17:29What state is your current rad in?
When did you last change coolant?
How is your water pump?

I've never track driven a 2 but I ran an SP240 kit with a water cooled turbo and it never had any issues with cooling.

Forgot to mention it's 2zz with limiter at 8600, and on slow tracks (less flow) and keeping it in high revs makes it even hotter. Higher speed tracks there's no issue that I recall of.

Water pump was changed 4-5 years ago, fluid 2 years ago. Rad is original but no leaks.

I would buy a cool parts rad from ebay and see if that makes a difference they are so cheap.

I have a Japan parts on the V6 and it wasn't a straight fit even though it was for a zzw30.

I don't remember ever hearing anybody with a 2zz complaining of high temps on track.

Last time I had temp issues it ultimately turned out to be head gasket.

Cool parts looks really cheap! But it's in UK, which means high shipping costs and now also taxes.. And I'm not doing the work myself, so I'd just rather do it right the first time without experimenting too much.

I've now found a supplier in Germany for Koyorad KL010929R for about 290 gbp with shipping. I'm getting closer to deciding for this one.

Quote from: Dev on February  1, 2021, 07:25I do not know the kind of thermostats our cars use but I have head of thermostats only partially opening up that exhibits the same behavior of creep when the engine is stressed otherwise this shouldn't happen as our cooling systems are quite robust with some using the factory radiator for other engine swaps with larger displacements.

Thanks for chiming in from the US! I recall your posts from spyderchat :)

Is there a way to check thermostat is fully opening? I guess I could make sure that radiator is super hot when this happens by touching the hoses there?

I've also heard the thermostat is quite a hassle to reach with engine in the car?

Quote from: inside on February  1, 2021, 10:19

Quote from: shnazzle on February  1, 2021, 07:42You're not running a standalone ecu are you?
As said above, overheating is not something we see often.
If you are running a standalone or some kind of modification that is causing the car to run lean, that may be causing temperature to increase.
Just as an example, when I ran my piggyback leaner I would often get to 93-94deg. When I switched back, it would never go beyond 91.

Yes ecumaster with wideband. It is running a bit leaner because stock was very rich. It also runs higher revs and lower lift point, imho the revs contribute a lot too. I didn't have this creep on stock ecu... But then again, I don't have the issue on higher speed track.

Higher speed generally does cool better. 

It's something I'd definitely look into tbh. Overfueling on overrun for example will allow your cylinders and exhaust to cool before pelting it down the straight again. 
RRR are definitely well-versed in this, if you want to pay them a visit. 
Running lean will absolutely be hammering your temps.

Quote from: inside on February  1, 2021, 10:23

Quote from: 1979scotte on January 31, 2021, 18:23

Quote from: inside on January 31, 2021, 17:49

Quote from: 1979scotte on January 31, 2021, 17:29What state is your current rad in?
When did you last change coolant?
How is your water pump?

I've never track driven a 2 but I ran an SP240 kit with a water cooled turbo and it never had any issues with cooling.

Forgot to mention it's 2zz with limiter at 8600, and on slow tracks (less flow) and keeping it in high revs makes it even hotter. Higher speed tracks there's no issue that I recall of.

Water pump was changed 4-5 years ago, fluid 2 years ago. Rad is original but no leaks.

I would buy a cool parts rad from ebay and see if that makes a difference they are so cheap.

I have a Japan parts on the V6 and it wasn't a straight fit even though it was for a zzw30.

I don't remember ever hearing anybody with a 2zz complaining of high temps on track.

Last time I had temp issues it ultimately turned out to be head gasket.

Cool parts looks really cheap! But it's in UK, which means high shipping costs and now also taxes.. And I'm not doing the work myself, so I'd just rather do it right the first time without experimenting too much.

I've now found a supplier in Germany for Koyorad KL010929R for about 290 gbp with shipping. I'm getting closer to deciding for this one.

Didn't realise you were outside the UK.

If you want a Koyo go for it. Or a mishimoto.
My car previously had a mishimoto and that developed a leak.
I'm still not convinced that is the cause of your problem.
I am no mechanic but have helped changed two rads and coolant on driveways with basic tools its very easy.

Quote from: shnazzle on February  1, 2021, 11:48

Quote from: inside on February  1, 2021, 10:19

Quote from: shnazzle on February  1, 2021, 07:42You're not running a standalone ecu are you?
As said above, overheating is not something we see often.
If you are running a standalone or some kind of modification that is causing the car to run lean, that may be causing temperature to increase.
Just as an example, when I ran my piggyback leaner I would often get to 93-94deg. When I switched back, it would never go beyond 91.

Yes ecumaster with wideband. It is running a bit leaner because stock was very rich. It also runs higher revs and lower lift point, imho the revs contribute a lot too. I didn't have this creep on stock ecu... But then again, I don't have the issue on higher speed track.

Higher speed generally does cool better.

Running lean will absolutely be hammering your temps.

Running lean at high rpm is a good way to experience knock and all the danger that brings.

Quote from: 1979scotte on February  1, 2021, 11:51

Quote from: shnazzle on February  1, 2021, 11:48Higher speed generally does cool better.

Running lean will absolutely be hammering your temps.

Running lean at high rpm is a good way to experience knock and all the danger that brings.

Didn't say lean! Just leaner than stock, which was very rich. (Forgot the exact numbers)

But you all make a good point, it's also something I can easily check again as I have wbo2.

I've always contributed higher temps to higher revs that come with standalone - higher rev range where you spend most of the time on track. I guess it can also be running leaner. Or both.

¯\_(ツ)_/¯

Quote from: inside on February  1, 2021, 10:31

Quote from: Dev on February  1, 2021, 07:25I do not know the kind of thermostats our cars use but I have head of thermostats only partially opening up that exhibits the same behavior of creep when the engine is stressed otherwise this shouldn't happen as our cooling systems are quite robust with some using the factory radiator for other engine swaps with larger displacements.

Thanks for chiming in from the US! I recall your posts from spyderchat :)

Is there a way to check thermostat is fully opening? I guess I could make sure that radiator is super hot when this happens by touching the hoses there?

I've also heard the thermostat is quite a hassle to reach with engine in the car?

 They say you remove it then boil it in water to check to see it fully opens. Considering the location its better to just exchange it with a new factory one. I do hear they can be hard to have enough clearance but so many have gained access.

 I just remembered. There is a situation where some 2ZZ swap people have encountered as a source of overheating.
 It is believed that the 2ZZ  water jackets sits higher than the 1ZZ due to the nature of the position of the engine. This creates an issue at the coolant reservoir allowing it to take in more air.
 The expansion tank is not just for holding coolant it also dissipates the air in the system constantly by burping its self.

  Someone on Spyderchat found the solution was to add a restrictor to the tank  to allow the bleeding of bubbles in the system by not allowing the expansion tank to level down.

 The other way of handling this is to overfill the expansion tank so that the coolant level is higher. If the full level marker is at the halfway position  when cold then fill it up to 3/4. There is no harm in overfilling as it will just overflow out excess. 

 I would try this first and see if it solves the issue. I would also go on Spyderchat and read up on the solution as it is well documented and discussed. 

Quote from: 1979scotte on February  1, 2021, 11:48

Quote from: inside on February  1, 2021, 10:23

Quote from: 1979scotte on January 31, 2021, 18:23

Quote from: inside on January 31, 2021, 17:49

Quote from: 1979scotte on January 31, 2021, 17:29What state is your current rad in?
When did you last change coolant?
How is your water pump?

I've never track driven a 2 but I ran an SP240 kit with a water cooled turbo and it never had any issues with cooling.

Forgot to mention it's 2zz with limiter at 8600, and on slow tracks (less flow) and keeping it in high revs makes it even hotter. Higher speed tracks there's no issue that I recall of.

Water pump was changed 4-5 years ago, fluid 2 years ago. Rad is original but no leaks.

I would buy a cool parts rad from ebay and see if that makes a difference they are so cheap.

I have a Japan parts on the V6 and it wasn't a straight fit even though it was for a zzw30.

I don't remember ever hearing anybody with a 2zz complaining of high temps on track.

Last time I had temp issues it ultimately turned out to be head gasket.

Cool parts looks really cheap! But it's in UK, which means high shipping costs and now also taxes.. And I'm not doing the work myself, so I'd just rather do it right the first time without experimenting too much.

I've now found a supplier in Germany for Koyorad KL010929R for about 290 gbp with shipping. I'm getting closer to deciding for this one.

Didn't realise you were outside the UK.

If you want a Koyo go for it. Or a mishimoto.
My car previously had a mishimoto and that developed a leak.
I'm still not convinced that is the cause of your problem.
I am no mechanic but have helped changed two rads and coolant on driveways with basic tools its very easy.

I too ran a Mishimoto rad (2ZZ, had to cut the slam panel) which developed a leak. Very frustrating.

Replaced with an OEM Koyo rad, and have had zero issues since.

Quote from: Alex Knight on February  2, 2021, 07:19

Quote from: 1979scotte on February  1, 2021, 11:48

Quote from: inside on February  1, 2021, 10:23

Quote from: 1979scotte on January 31, 2021, 18:23

Quote from: inside on January 31, 2021, 17:49

Quote from: 1979scotte on January 31, 2021, 17:29What state is your current rad in?
When did you last change coolant?
How is your water pump?

I've never track driven a 2 but I ran an SP240 kit with a water cooled turbo and it never had any issues with cooling.

Forgot to mention it's 2zz with limiter at 8600, and on slow tracks (less flow) and keeping it in high revs makes it even hotter. Higher speed tracks there's no issue that I recall of.

Water pump was changed 4-5 years ago, fluid 2 years ago. Rad is original but no leaks.

I would buy a cool parts rad from ebay and see if that makes a difference they are so cheap.

I have a Japan parts on the V6 and it wasn't a straight fit even though it was for a zzw30.

I don't remember ever hearing anybody with a 2zz complaining of high temps on track.

Last time I had temp issues it ultimately turned out to be head gasket.

Cool parts looks really cheap! But it's in UK, which means high shipping costs and now also taxes.. And I'm not doing the work myself, so I'd just rather do it right the first time without experimenting too much.

I've now found a supplier in Germany for Koyorad KL010929R for about 290 gbp with shipping. I'm getting closer to deciding for this one.

Didn't realise you were outside the UK.

If you want a Koyo go for it. Or a mishimoto.
My car previously had a mishimoto and that developed a leak.
I'm still not convinced that is the cause of your problem.
I am no mechanic but have helped changed two rads and coolant on driveways with basic tools its very easy.

I too ran a Mishimoto rad (2ZZ, had to cut the slam panel) which developed a leak. Very frustrating.

Replaced with an OEM Koyo rad, and have had zero issues since.

You've ran yours on track for a long time Alex have you always had a bigger rad?
Any issues with temps?

Quote from: 1979scotte on February  2, 2021, 08:21

Quote from: Alex Knight on February  2, 2021, 07:19

Quote from: 1979scotte on February  1, 2021, 11:48

Quote from: inside on February  1, 2021, 10:23

Quote from: 1979scotte on January 31, 2021, 18:23

Quote from: inside on January 31, 2021, 17:49

Quote from: 1979scotte on January 31, 2021, 17:29What state is your current rad in?
When did you last change coolant?
How is your water pump?

I've never track driven a 2 but I ran an SP240 kit with a water cooled turbo and it never had any issues with cooling.

Forgot to mention it's 2zz with limiter at 8600, and on slow tracks (less flow) and keeping it in high revs makes it even hotter. Higher speed tracks there's no issue that I recall of.

Water pump was changed 4-5 years ago, fluid 2 years ago. Rad is original but no leaks.

I would buy a cool parts rad from ebay and see if that makes a difference they are so cheap.

I have a Japan parts on the V6 and it wasn't a straight fit even though it was for a zzw30.

I don't remember ever hearing anybody with a 2zz complaining of high temps on track.

Last time I had temp issues it ultimately turned out to be head gasket.

Cool parts looks really cheap! But it's in UK, which means high shipping costs and now also taxes.. And I'm not doing the work myself, so I'd just rather do it right the first time without experimenting too much.

I've now found a supplier in Germany for Koyorad KL010929R for about 290 gbp with shipping. I'm getting closer to deciding for this one.

Didn't realise you were outside the UK.

If you want a Koyo go for it. Or a mishimoto.
My car previously had a mishimoto and that developed a leak.
I'm still not convinced that is the cause of your problem.
I am no mechanic but have helped changed two rads and coolant on driveways with basic tools its very easy.

I too ran a Mishimoto rad (2ZZ, had to cut the slam panel) which developed a leak. Very frustrating.

Replaced with an OEM Koyo rad, and have had zero issues since.

You've ran yours on track for a long time Alex have you always had a bigger rad?
Any issues with temps?

I had the Mishimoto rad for a couple of years, and had it on track.

I did have a recurring intermittent issue with rising temperatures from time to time. This was eventually traced to the Mishimoto radiator which had developed a very small weep. This allowed air to ingress to the coolant system, which in turn allowed hot spots, and rising temperatures.

I've had zero issues on track with the OEM Koyo rad, and have done hundreds and hundreds of miles on track with it. Well recommended.

Quote from: Alex Knight on February  2, 2021, 11:19I had the Mishimoto rad for a couple of years, and had it on track.

I did have a recurring intermittent issue with rising temperatures from time to time. This was eventually traced to the Mishimoto radiator which had developed a very small weep. This allowed air to ingress to the coolant system, which in turn allowed hot spots, and rising temperatures.

I've had zero issues on track with the OEM Koyo rad, and have done hundreds and hundreds of miles on track with it. Well recommended.

Thanks for reply Alex, love some first hand experience!

Do you have A/C and do you have performance/alu or normal koyo radiator?

Quote from: inside on February  2, 2021, 12:20

Quote from: Alex Knight on February  2, 2021, 11:19I had the Mishimoto rad for a couple of years, and had it on track.

I did have a recurring intermittent issue with rising temperatures from time to time. This was eventually traced to the Mishimoto radiator which had developed a very small weep. This allowed air to ingress to the coolant system, which in turn allowed hot spots, and rising temperatures.

I've had zero issues on track with the OEM Koyo rad, and have done hundreds and hundreds of miles on track with it. Well recommended.

Thanks for reply Alex, love some first hand experience!

Do you have A/C and do you have performance/alu or normal koyo radiator?

No problem, happy to share.

I do have A/C, and a normal Koyo radiator. Think it was about £40ish from memory.