Radiator upgrade

[bdi_fc]

I've been searching the e36 forums on bimmerforums.com and found the following options:

• Zionsville 33mm Aluminum radiator
• Pwr 40mm core radiator
• Fluidyne 38mm Aluminum radiator
• Pwr 57mm core radiator

Links:

http://www.absoluteradiator.com/ProductPage.asp?idProd=53

http://www.zionsvilleautosport.com/store/shop.mv?Screen=PROD&Store_Code=6134&Product_Code=NP-ALLOYRAD&Category_Code=CCSE30

My S52 swap heats up to just before the 3/4 mark on the e30 gauge in stop and go LA traffic.
I swapped the thermostat and aux fan switch to 80C sensors.

Questions:

• Am I correct in thinking the e30 gauge is more accurate than the e36 gauge? Doesn't it reflect more variations as opposed to the e36 overheat gauge?
• The e36 motor comes by default with an 88C thermostat, is it safe to assume that the car is running cool with the 80C and the e30 gauge reflecting under 3/4?
• Which radiator should I switch to to improve cooling? From what I read on BF.C, the zionsville and other smaller core radiators just offer better end tanks that are aluminum instead of plastic. The only way to improve cooling is to improve the transfer material (aluminum) and increase the core size, right? Shouldn't I switch to the PWR 57mm then?
• As it stands with the OE 89 e30 radiator, it's close to the engine. Any thin aux fan recommendations?
• Would it be better to stay OE on the radiator and just get a nice puller fan?

Thanks!

[BimmerToad]

I hate LA traffic for that, along with other obvious reasons ;)

I don't have any experience with upgraded radiators, but I would highly recommend installing a pusher fan infront of your radiator. I installed the thinnest 16" Spal fan I could find, and wired it up to a thermostatic switch on the radiator. Once the needle reaches just over half, the fan turns on and keeps the bay cool. I wired it to the AC aux fan circuit, so the AC cabin switch turns on the fan too, which is fortunate since somehow the connection to the thermostatic switch has failed.

With the fan on, in traffic, I'm about 4 needle thicknesses below 1/2 way (if that makes any sense), and I'm running Water Wetter, and about a 25% coolant mixture.

Installing a fan ahead of the radiator also frees up room between the timing case and the radiator.

[Erick]

I'm about to get an all aluminum SR20DET Koyo radiator... the measurements are fairly similar, 57mm core and the inlet/outlet are in the exact same location. It's not as tall as the stock radiator, so I can mount my oil cooler under it and finally put my high beam back on.

Flex-a-lite fans will replace the fan clutch.

[matt]

Clutch fans. You all need them.

[Erick]

The clutch fan wont fit with the 57mm radiator. At least not by my estimates.

[bdi_fc]

So, you all suggest dumping the stock pusher and upgrading to something else?

Any recommendations on how to mount that while keeping the A/C condenser?

No way the clutch fan will fit, especially if I upgraded radiators.

[bdi_fc]

Thinnest electric fan I could find online is a SPAL low-profile fan that is 2.05" deep.

I just went out to my car and measured from the distance from the front of the VANOS and the radiator and it is about 2". I notice that with the e30 radiator top support bracket, there is about a half inch or less of space between the condenser and the radiator. Can this gap be closed?

I'm thinking if I offset the fan a bit, I can avoid any clearance issues.

[matt]

So, you all suggest dumping the stock pusher and upgrading to something else?

Any recommendations on how to mount that while keeping the A/C condenser?

No way the clutch fan will fit, especially if I upgraded radiators.

There are fans that fit.

Fan > upgraded radiator

[bdi_fc]

I purchased the 30100400 spal fan.

• 16"
• Straight Blade
• Puller
• 2.05" deep
• $65.95
• bracket & strap mounts $10.00 30130011

[Mike B.]

That fan is actually 3.39" deep when you count the depth of the motor. Check the .pdf specs here - http://www.slickcar.com/pdfs/16Fans.pdf

[bdi_fc]

That fan is actually 3.39" deep when you count the depth of the motor. Check the .pdf specs here - http://www.slickcar.com/pdfs/16Fans.pdf

Those specs don't apply the fan I purchased (30100400).
These do:

http://www.spalusa.com/fans/automated/tech_sheets/0400-0401.pdf

[Erick]

There are fans that fit.

Fan > upgraded radiator

If you're going to do fan alone, then might as well leave the clutch fan with the stock shroud and all that. Wire a switch to the A/C fan and just run water on the cooling system (unless you're in a part of the country where it actually gets ridiculously cold... and even then... use water for summer time)

I figure if you're going to change the radiator, the fan must be upgraded at the same time. One is pointless without the other.

[matt]

What I'm trying to tell you is that an electric fan is not an upgrade over the stock clutch fan.

[bdi_fc]

What I'm trying to tell you is that an electric fan is not an upgrade over the stock clutch fan.

I disagree.

• The clutch fan is limited to spinning at the engine speed.
• The clutch fan drags on the overall engine.
• The clutch fan is larger and takes up more space.

Even if the airflow is the same, there are ancillary benefits to the e-fan over the clutch fan.

[Erick]

I disagree.

• The clutch fan is limited to spinning at the engine speed.
• The clutch fan drags on the overall engine.
• The clutch fan is larger and takes up more space.

Even if the airflow is the same, there are ancillary benefits to the e-fan over the clutch fan.

Many e-fans cannot flow as well as the clutch fan at higher rpms.