Hey guys. After 3 or 4 hot laps at Cayuga road course or Dunnville, my car’s coolant temp starts creeping up. This is even while having the heater on full blast. I have also tried lowering my upper rad hose and using a coolant additive called water wetter. Both of these attempts didn’t do shit.
This is my setup:
Any suggestions?
Its probably a way too fat shitty FMIC casuing your issue.
The FMIC is a rather small Precision cooler that doesn’t black the rad too much.
grab an oil cooler.
itll drop your engine temps a good 10 degrees
Could try:
maybe you water pump tensioner mine did that (ka24de) and it only went up when i ran the car semi hard
x2 - except if you really want to be ballin’ hard find a mark VIII fan. I have only ever found one left in a jy and I pulled it asap, and is on my s13.
I can also sell you a taurus 3.8 fan if you need - they’re not very easy to come by either.
Ahem… the fan’s shouldn’t be coming on / don’t do shit while your DRIVING at 20-150kph…
Or just stop trying to keep up with me rammy. ;p
Ahem… the fan’s should be coming on / do lots of shit while your “After 3 or 4 hot laps at Cayuga road course or Dunnville”…
I didn’t realize you had a car at the track Dusty :P…
I’ll try some of the suggestions in this thread. Hopefully something works. I miss being able to go around the track as long as I wanted in my stock KA.
Try out a Nismo t-stat. I know it seems simple but how are you bleeding your system?
I picked up one of these: 
It makes bleeding the system a whole lot easier. I sealed up a lot of the gaps around the radiator and it made my system a whole lot more efficient. Try making some cooling panels.
I had a similar issue. Except i got taurus fan. I m switching to altima fans. And i re bleed the entire radiator system.
Let me know what helps you man.
Are you using an aftermarket temp gauge??? Alot of people tend to believe that their cars are overheating at the track by seeing a rise in their stock temp gauges when 99% of the time its nothing to worry about.
the stock gauge is very poor and sensitive for measuring true temps as it rises drastically even a little over normal operating temps which is normal on a race track…
best way to monitor your temperature is by installing a good after market water temp guage that actually shows you degrees C/F…
anyway fans are usually the culprit especially on an SR with a koyo rad,good luck
+1. Exactly what Dustin said.
Best thing you can do is ducting and making sure your coolant is properly bled as well.
Create ducting after the FMIC and make sure that all the air is forced through the rad. Do you still have the factory grey “sponge” inbetween your radiator and the rad support? If not, make something up. Also, try getting one of those radiator shrouds that come on stock SR rads.
You could also try getting a NISMO thermostat if those thing’s don’t help you.
Fans don’t help you while you’re driving. When you’re idling or driving 10kph it does.
1 question
Why did’nt you stay with the stock crank fan?
It could be a couple of things: Bad T-stat, Bad temp gauge , (most likely tho) The bleeding process? It takes time to bleed a coolant system and patience.
Ill bring my spill free funnel when I get back and do it for you. after its fixed you have to come to the track and settle this. muahhhahahah lol (its nick by the way )
I have seen people do water pumps and bleed a system in under 3 mins and I’m like what the fuck with 80% coolant too! lol
Are you running all water or 50/50?
Aren’t they the same fan motor? I thought just the blade design and shroud was different.
Either way, I’ve made a semi-simple electronic circuit that uses a 1992 Sentra rad fan switch and a 1987 Z31 a/c condensor fan switch and I have the two stage taurus e-fan running on my z31, and for the 500km that I’ve been beating on the vg33et (0 psi for break in), I’ve never seen the temp on my new racing rad go over the half way mark on the gauge. and the oil temp is rock solid at the middle.
if you can keep the water at the proper temp for most of the time the oil will have a tendency to stay cooler and might negate the effects of needing to plumb oil cooler lines, to even further inhibit air to the radiator by putting it infront of the FMIC (if that’s where s13 ppl put them?).
I think the taurus fan pushes something like 2500cfm on low and 4000cfm on high, and my circuit makes the low speed turn on at 189 and off at 182 F, and the high speed turns on at 212 and off at 200 F. I did this with two sensors and two 70 amp relays, and it’s been good for 2 weeks now.
I’ve never seen it go to high speed.
My advice would be to try and duct as much air and seal off gaps at the front of the car leading to the rad, and use aluminum tape temporarily in small places that air will go through to see if it helps, then build something better once you’ve solved the issue. And upgrade to the Taurus or the Mark VII fan if it’s better. I know the Taurus one will suck the leaves off the pavement on low and stick them to your rad (which is why I put black windscreen infront too, to protect my 500 dollar custom rad from rocks and stop leaves from getting in behind my bumpers and rad.
Also try and run a bit more water in your mix (the coolant won’t do much in the weather we’re having lately) 30 % coolant in this temperature as of late is fine and will extract more heat per volume of fluid pumped.
The FMIC may not be the problem, I think it’s the air going around the rad rather than through it. seal it up.
Mark VIII (P# RF123) fans do not have the same motor as the Taurus 3.8 fans, and they have 18" blades compared to 17". Output is said to be 3000+ CFM on low and up to 4900 on high 
Similar RF125 fans use a Lincoln motor on a taurus 17" fan, which still gives good CFM, but not RF123 output. RF24 and taurus fan’s are the ford motor on the 17" blades which put out something like you said 2500 low and 3900 high.
Maximum draw on startup for either is still under 45 amps I believe, with average high draw of 30-35 for the bigger RF125 motor, 25-30 for the RF123.
Sounds like you have a solid setup though, I’m overbuilding the hell out of mine, but yours is more than enough - is the Z31 switch ballin’ or why did you choose it?
I chose the Kouki Z31 because I like the look and the 80’s raw feel that the Z31’s have over the 240sx’s, the immense torque I’ve got from the vg33 (and I’m currently at 0psi for break-in, too!), and because I just think it’s a cooler car over all.
The fan setup I have uses two 70amp relays in a home electrical box that is hidden beside the radiator, behind my oil catch can, which is a stainless thermos. LOL. You would never know, and the engine detail takes away attention from that area anyway.
Not sure what the term “swithc ballin’” means… ?
As for the fan datum, thanks for that. I think my next purchase will be the larger Mark VIII fans. Which cars use the RF123 motors on their fan assemblies?
The only car i’ve heard of is the lincoln mark VIII and there is a truck running the same fan but I forget which, sorry.
I’m an idiot and missed the part where you said you had a z31 - i took it as you were only using a z31 switch ->> “switch ballin” means nothing lol
good call on the stainless house box never though about using one of those but I may look into it when I do up a solid relay setup.
Pics of z31? pm me lol we just did a vg30t z31 in my shop for my buddy, so I got an interest in them atm 