rb cooling question

[platez808]

i just finished my swap.. i have a sII rb25det in my s13. for the cooling, i'm currently running a a fat huge aluminum gtr radiator (had to cut/bend the lower radiator support and drop the power brace things to make it fit) with dual FAL pullers, stock hoses, no ac condensor, fmic, i'm assuming a stock thermostat, and right now running a radiator flush and water mix to clean everything out because the crap pouring out of the motor when i got it was a nice muddy red color..

the thing is that i'm still running the stock s13 gauge cluster (i know that the water temp gauges on the stock clusters are JUNK but atleast they give a rough idea on the temp for now), and after letting the car warm up and even driving it around with the fans on, the water temp needle doesnt even move. today i ran without the fans to see if there would be any movement and it actually went up to 2 bars, but as soon as i turned the fans on it dropped back to the position where it seemed like my gauge is broken.

1) Is my gauge broken? (it worked pretty well with my old motor swap about a month ago)2) Is my sensor broken?3) Are my sensor and gauge compatible? if not what should I use?4) Is my cooling setup that badass and just way too efficient for my own good??5) Is everything I'm seeing in terms of my temps shown by my gauge normal and RB25s just run that much cooler naturally compared to SRs?

Thanks ahead of time.

[rb240det]

Well you are correct the stock gauge is absolute crap. I would invest in a good aftermarket water temp gauge. The stock gauge on my first swap would show the need at the 3/4 mark, while the Autometer gauge showed my true temp hovering around 180*. Don't rely on the stocker...

[lexrob]

You don't have to go with a expensive one. Autoguage makes mechanical ones for like 15$ which are just as accurate. Your paying for ease of installation with electronic. Not to say the defi ones are not magnificent!!!!

[rb25det250sx]

well, the stock temp sensor on the Rb dont read correctly for the stock temp gauge. mine reads about halfway. and its about the right temp, because any higher and it starts boiling... mayb its to high, i need to get a aftermarket temp gauge tho..you should do the same.

[burnin240sx]

did you take the temp sensor out of the KA and put it in the RB? that is one reason. but the stock gauge reads hot at like 220 when it's too late. Get one of the $20 gauges, it's ugly but beats blowing up your ride.

[platez808]

alright so i swapped out the rb coolant temp sensor with the one from my KA and it works as it should.. it warms up and the needle goes to the third bar and stays their at cruising and when the fan is on while not moving..

but i figure that i should use an aftermarket one...

will aftermarket electrical water temp gauges work with the stock sensor? if you have to use a different sensor where is a good place to put it and how? how would a mechanical gauge hook up too?

[skylinegtr20]

What do you mean by "fat huge aluminum GTR radiator", like a koyo, mishimoto or PWR?

fmic isn't part of the same cooling system

i just finished my swap.. i have a sII rb25det in my s13. for the cooling, i'm currently running a a fat huge aluminum gtr radiator (had to cut/bend the lower radiator support and drop the power brace things to make it fit) with dual FAL pullers, stock hoses, no ac condensor, fmic, i'm assuming a stock thermostat, and right now running a radiator flush and water mix to clean everything out because the crap pouring out of the motor when i got it was a nice muddy red color..

the thing is that i'm still running the stock s13 gauge cluster (i know that the water temp gauges on the stock clusters are JUNK but atleast they give a rough idea on the temp for now), and after letting the car warm up and even driving it around with the fans on, the water temp needle doesnt even move. today i ran without the fans to see if there would be any movement and it actually went up to 2 bars, but as soon as i turned the fans on it dropped back to the position where it seemed like my gauge is broken.

1) Is my gauge broken? (it worked pretty well with my old motor swap about a month ago)2) Is my sensor broken?3) Are my sensor and gauge compatible? if not what should I use?4) Is my cooling setup that badass and just way too efficient for my own good??5) Is everything I'm seeing in terms of my temps shown by my gauge normal and RB25s just run that much cooler naturally compared to SRs?

Thanks ahead of time.

[platez808]

What do you mean by "fat huge aluminum GTR radiator", like a koyo, mishimoto or PWR?

fmic isn't part of the same cooling system

as far as company that made the radiator, i didnt see any marings on the radiator so i dont know what company made it (nor do i care.) All i do know is that it is much taller than s13 radiators (which is why i had to make the modifications to fit it) and just as thick if not thicker than the koyo that i did have before in my SR swap.

haha.. and i know very well that the fmic isn't part of the cooling system.. but what i do know is that the location of the fmic, size, angle, or just the fact that you have one can greatly affect the airflow to the radiator thus affecting cooling which is why i found it important to list it in my thread, but i'm sure you only meant to help me by educating me in the inner workings of turbocharged internal combustion engines
Modified by platez808 at 5:19 PM 8/26/2009

[lexrob]

I mounted my mech temp gauge in the long hose under the intake. I just got 5/8 hose, couple brass fittings from LOWES and clamper her on. Kind of ghetto looking but it works. I think it read a little low like 150 crusin and 180-190 idle. Im going to use water/Water Wetter haha "good for -30deg." More like -10 according to importtuner Rb's are supposed to run HOTTT!!(((in 240's))) but i have no problems just precautionary.

Stock looking plastic end cap rad. but has koyo stamped on it....???? it works good.

[l0nestar]

WOW!The RB sender will not work with the KA cluster. Upgrade to a decent electric gauge or use an inline hose adapter + mech gauge.

Personally, I tapped my factory manifold in the same place that factory temp sender was located. All that I use from my factory cluster is the tach and fuel level.

I upgraded my entire system to a Defi Link-Meter solution. (boost, EGT, coolant, oil press, oil temp) I like it, it works.

I had a ProSport electric water-temp gauge. it worked.

I would have replaced the thermostat with a new one while I had it apart. Easy Fix.

Also, the "muddy red color" is iron oxide (a.k.a. RUST) Your using a cast IRON block.. this is somewhat typical for a motor that has been setting for a while.