Trans cooling for C4 how to plumb it?

[billtroth]

I want to make sure my new C4 and converter don't run too hot so I bought a Derale "Electra-Cool" unit.  I went on line to get some opinions on where to plumb into my car. I found a lot of opinions but no clear consensus on which of these options works best. 
1. Don't use the engine radiator cooler ( my Ron  Davis radiator has one ), just use the Derale.
2. Route the fluid from the trans to the radiator cooler first then through the Derle cooler with its fan running continuously.
3. Route the fluid from the Derle cooler ( either with or without the fan running ) first then through the engine radiator cooler.

I am leaning with the #2 option and put a thermostat switch on the Derale to turn on the fan at about 210 degrees.

If anyone is running an electric fan trans cooler in conjunction with the car radiator cooler in their drag car and can share experience please let me know.

[plovett]

On my C6 I used your option number 2.  You can read opposing opinions on the net, of course.  I like running it through the radiator first and then auxiliary cooler.  That way the different fluids in in the car get up to temp faster.  If the coolant heats up faster than the transmission fluid, then it helps the transmission fluid get to temp faster.  And vice-versa.  Though I know the engine coolant heats up faster in practice.  Then you have the auxiliary trans cooler to take some heat out before it gets back to the transmission.  Having the two coolants running together in the radiator helps to moderate extreme high or extreme low temps.    It makes sense to me.

I've had my car plumbed that way for years with no issues.  I don't know if it is the best way for all circumstances.  It has worked for me.

Oh yeah, I don't have a fan on my auxiliary trans cooler.  Just FYI.

JMO,

paulie

[JamesonRacing]

Bill,

I have the trans cooler in the trunk of my Fairlane.  Deep pan on the trans to gain some volume, then hard lines into the trunk, B&M Super Cooler with a fan on it.  I have a thermal switch for the fan so it kicks on when the fluid is hot.  Back in the pits I just crack the trunk and let any hot air exit.  In a drag only car, you generate heat for less than twelve seconds, so you're fine so long as you have adequate fluid volume and a way to manage the peak temperature. 

The advantage is that you don't have to run lines up to the busy part of your car, you don't have anything blocking the radiator, and there's a couple pounds now in the back of the car rather than being right on the nose. 

[Falcon67]

Don't bother with the radiator.  Run the fan/cooler combo if you have room for it.  I would NOT use a auto temp control on a drag car - make it a manual switch.  Fan loads on the alternator can impact your ET if you are running on a dial in.  On the cars here, I use a large 3/4" aluminum cooler positioned in front of the radiator so the main fan pulls air across it.  I don't see trans temps approaching 180 except in the summer and in the later rounds.  I run a 4200 stall in a 3000lb car and it comes back about 150 from a pass, starting at barely showing on the temp gauge heading to the lanes.  If I need more cooling, I carry a blower to blow air on the trans for a while, then idle the car.  This is a rare condition - ground still 100F at 9 PM and 4 cars left.

I use a 16 pass Derale unit on the dragster - Powerglide, high stall - very hard to get that trans hot unless hot lapping in later rounds so I seldom run it other than switch it on after a pass and let it run while I motor back to the pit.  If your door car makes heat, then run the cooler the whole pass or do the same - switch it on when returning to the pit.  Run it in staging, switch off when heading for the burnout box. 

ALSO - make SURE you have a quality gauge and the correct compatible temp sender.  Autometer has more than one and I found myself chasing high indicated trans temps in the dragster - 180~200 after a pass - only to find out the wrong sender was in the pan.  One day finally shot trans with a laser to check the temp and found that "180F" was more like 130F.

[mbrunson427]

When we used to run the '64 Fairlane drag car, we ran it just the same as you explained in your option #2. We didn't do it with the idea that we were adding additional cooling capacity, but figured that the additional fluid volume in the radiator couldn't hurt. It had a deeper pan too. The setup was probably a little overkill, but never ran into a problem.

We got into a debate when we were installing it about what temperature reading was more important, supply or return from the cooler. Uncle Doug wanted to know whether or not the cooler was doing its job, and I was concerned about the leaving fluid temp from the transmission. We finally said screw it and put a temp sending unit on both and had a toggle switch where you could flip between either reading. Of course it wasn't necessary, but it was kind of fun to look at on the return road.