Cooling issues with S52 swap and AC and pusher fan

[HoustonF34]

I went through a lot of the build forms but didn't see a clear answer to my problem.

92 325i vert with 99 S52, 5 speed from same M3. AC from donor car installed and works great.

E30 temp gauge shows hair over 1/4 at highway speeds. Doesn't matter if AC is on or off.

Temp gauge goes to 1/2 in town as long as traffic is moving. Having AC on helps because there is an E30 M3 pusher fan on AC condenser.

With AC off
Stop and go traffic or any high rev low speed horse play gauge goes to 3/4 quickly. Hasn't overheated yet but pretty sure getting caught in traffic jam or autocross would cause her to overheat.

With AC on gauge reads hair over 1/2 sitting still. (Used to go to 3/4 but I custom fit an e30 325 shroud. Few cuts to get around new position of the S52 fan.

Also failed emissions on high Nox low speed 15mph. Standard was 970ppm and she blew a 2277ppm, but passed by 10 ppm at high speed 25mph.

99 M3 S52 100k about 15k in E30.
Original 325i radiator.
clutch fan, with shroud
AC condensor installed in front of radiator with pusher fan, only comes on when AC is on.

What I would like to do is get new aluminum rad and nice electric puller fan.
Does anyone know a good combo that fits?
Bigger radiator and thin fan or same size radiator with bigger fan?

Living in Houston AC has to stay. Not sure if leaving rad/clutch fan and bigger pusher fan on the condenser and rad would be enough.

any advice or set up that is known to work would be great
Thanks

[HoustonF34]

https://www.youtube.com/watch?v=gakU4_rdBiU

[dude8383]

Something tells me your clutch fan isn't working at idle well.

[sublimation]

What temperature thermostat do you have ? My S52 with AC and E36 M3 rad runs at 3/4 with a spal pusher which is about 205-210 degrees when IR'd on the thermostat housing. 200-210 is within running condition of the later model motors.

I'd suggest correlating what your cluster shows you to another reading - either IR on the thermostat housing or a secondary gauge.

[exhaust]

Agreed that it sounds like your mechanical fan isn't doing its job. Is the clutch good? And blades broken?

As for a radiator/puller combo, Mishimoto E36 radiators have a good reputation as do Z3M radiators although they might be a little big if you're keeping AC.

http://store.bimmerworld.com/spal-electric-fans-p1160.aspx

Go through those fans and find the 16" low profile puller. You'll need mounts as well unless you can fabricate something.

[mpowerful]

Yeah check your fan clutch. I run nearly same setup and its ample cooling with a/c in new orleans. I had issues last summer running warm but it was naggling shit like heater hoses were on backwards and tiny coolant leak through the thermo housing where lift hook bolt goes through. Once i had that all sorted everything has been perfect and it has been a really hot summer over here in nola. Hottest it ever gets is just a hair past center.

[HoustonF34]

Thanks for your help everyone. I tested the Clutch fan this morning and it is not working.

Sounds like SPAL electric is better than fixing Clutch fan?

[dude8383]

Thanks for your help everyone. I tested the Clutch fan this morning and it is not working.

Sounds like SPAL electric is better than fixing Clutch fan?

I'd say that the clutch fan is far more capable at keeping the car cooler. The power loss is negligible especially since you've got an S52 in there.

Ever customer car that I've built with a 24v gets a diesel fan clutch because it eliminates any worry of the car overheating in NYC heat.

[zcenterb]

I went with Spal 16 high perf. Pusher for my S50. No AC though. And no mechanical fan. I am running a Stewart's water pump and a Mishimoto radiator though. I have a Autometer water temp gauge and I've never seen it crack 195, even on a 100 degree day with spirited driving.

[dude8383]

I went with Spal 16 high perf. Pusher for my S50. No AC though. And no mechanical fan. I am running a Stewart's water pump and a Mishimoto radiator though. I have a Autometer water temp gauge and I've never seen it crack 195, even on a 100 degree day with spirited driving.

You're in VT :P

I've got a Stewarts pump as well and in NYC traffic that lower temp switch on the aux fan is always kicking on to keep things cool. I don't have my radiator side electric fan hooked up yet though.

A car with a/c will generate a shit ton more heat though so that mechanical fan really does a great job keeping temps in check :up: