two tranny coolers instead of one

#1 01-27-2002, 07:19 AM

I was just curious about this that's why I wanna discuss this. I have read that an extra tranny cooler cools down transmission fluid by 20%. But how about if we put two extra tranny coolers in series, which will cool down tranny fluid by 40%?? will it be more effective. How about if we put 5 , it will cool it down to 100%, will it be exellent?? What do you guys think??

Beav · #2 01-27-2002, 07:41 AM

There's a little thing called More's Law that covers this: If this much is just right, more is better (close enough to get the point across.)

The transmission needs to get to a specific operating temp in order to perform properly, if overcooled it may become difficult to reach that temperature.

Beav

#3 01-27-2002, 07:45 AM

I thought about that, but I couldn't figure out that how much is just right? where can I find More's law, I would love to read how much is just right ??

Beav · #4 01-27-2002, 08:16 AM

More's Law is a generic term for someone trying to enhance the performance of an item by increasing its recommended specification(s) to a point where it actually does more harm than good.

I think the general consensus here is a cooler with a 19,000# rating is adequate. If you really wanted to see if it is I would start with that size and also install a temp gauge. If you find the gauge indicating high temperatures then add more cooling.

Beav

immortal_suby · #5 01-27-2002, 04:07 PM

I have 2 coolers on each SVX. One is the B&M that almost everyone here uses and the other is a perma cool with an electric fan. When we climbed up the peak at the smokies meet I still pegged the temp gauge - even with 2 coolers and the fan running. I think it was around 70 degrees that day.

I have monitored temperatures on the stock cooler alone (horrifying), a B&M(not much better), and a dual setup B&M and perma-cool on 2 different SVX's now.

It is too much cooling in the winter - I usually unplug the fan in november and turn it back on when the average temp is back up to the 60's. But with the fan unplugged in the cool weather the tranny will reach a high enough temperature to lock up the TC until it gets down below about 20 degrees on the highway. In city driving th tranny easily gets to 150-170 degrees.

It would be overkill up north. Again this winter I drove to NY and in the 10 degree weather on the interstate doing 85mph the tranny cooled down enough to unlock the TC - not good. In the north I would run only 1 cooler with a fan on it.

You really do need the fan for city driving. The tranny does not cool down without forced air in stoplight to stoplight 35mph driving. I do not think the radiator fans draw enough air through the radiator and condenser AND a tranny cooler to be effective. Again - this is with a cooler in front of both (I have not tried putting the cooler in between them) and I have run this setup on 2 SVX's now.

I used to run only the B&M 19000GVW and it did not cool enough. The tranny would normally get up to 220 in stop and go driving and keep going up unless I got up to a high enough speed to lockup the TC for a while and cruise.

Jamsvx · #6 01-27-2002, 06:39 PM

I have always been curious with regards the temperature of the SVX transmissions and how they are actually measured.

Where in the transmission is the sensor/probe/thermocouple (sp?) inserted to obtain the transmission temperature readings?

I ask since a temperature gauge, in addition to the transmission cooler, will be the first thing to go on my SVX when I get one...oh..hang on....there are pigs flying across the sky!!! *re: Jamsvx in an SVX*

Thanks

Jamsvx

nubs · #7 01-27-2002, 08:12 PM

I also have two coolers in the same basic configuration as immortal_suby.My gauge probe is located in the Permacool filter housing which is inline before any of the coolers.Pictures in my locker.
In city driving temps can still go as high as 210 The fan cooled cooler has a switch on it so I can turn it off until needed. I do not think it is overkill in the least. Until you have a gauge in your car you will never see what is actually needed to keep your tranny cool enough.

#8 01-27-2002, 11:12 PM

I didn't get one thing, you guys might think that I am stupid, but I am still learning. What is TC and what does locking and unlocking of TC means ??
hey mike, How much did both of your coolers cost and about how much did you pay for the installation ??

Seraph · #9 01-27-2002, 11:16 PM

I am assuming that you guys are installing the coolers in // instead of series right?

humm... got to get those too..

Lwin

#10 01-27-2002, 11:21 PM

I have been thinking aobut series, but how would prallel work? I am sorry if I annoy you guys very much but I haven't been dealing with cars for a long time.

#11 01-27-2002, 11:23 PM

hey mike, one question for you, how did you get that SVX writing on your wheel's hub cap??

1994SubaruSVX · #12 01-28-2002, 07:37 AM

i personally did not trust the stock tranny cooler. i bypassed it completely and opted to rely strictly on the cooling performance of my b&m. i installed it in the optimum position which is in front of the radiator and condensor.

i have had no trouble and the car runs great. i dont think there will be a cooling solution that is perfect in all conditions. the goal is to try an minimize the time the tranny is at high temps. i feel like i have done that, especially over stock and my stock tranny cooler kept my transmission alive for 60,000 miles. i feel like with the b&m cooler it should give me at least 60,000 but hopefully much more due to the obviously better cooling charateristics.

nubs · #13 01-28-2002, 02:49 PM

Quote:

Originally posted by ravi
hey mike, How much did both of your coolers cost and about how much did you pay for the installation ??

The one that is in front of the radiator is a B&M 70255 which I paid around $45.00 for. The one in the fender well is one I got at a salvage yard from an Explorer.It is exactly like the B&M . The fan is a radiator cooling fan from a Hyndia.I just grafted them together and mounted them in the drivers side fender well.

I do all my work myself, so I can't say what it would cost.

Quote:

Originally posted by ravi

hey mike, one question for you, how did you get that SVX writing on your wheel's hub cap??

I filled in the Subaru letters,repainted and cut out some SVX logos by hand and stuck them on.

immortal_suby · #14 01-28-2002, 05:37 PM

I have the same B&M 70255 and they are around $45. The fan cooled ones I use are perma-cool# 12511. I got the first one direct from perma-cool for almost $150 and the second from Summit (the middleman) for only $112. Go figure! Any cooler with electric fan will do, this one was easy in that it comes as a complete kit but I have to mention that I am on my second electric fan on my SVX. I drove to NY last year in the dead of winter and had not disconnected the fan. The salt, ice, debris, etc from the trip destroyed the fan motor bearings and I had to buy a new one. I drove again this year but disconnected the fan and then cleaned it once back in the south before running it again and have not had a problem with it.

I used a perma-cool filter kit on one car and a summit kit in another - they are identical and about equally priced - i think it was around $30. Both are installed before any cooler to get a true reading of how hot the tranny fluid is and have a pre-drilled hole to put in the sensor for a temp gauge. I bypassed the stock tranny heater on each car and run the B&M and then the perma-cool in series.

TC is the torque converter - think of it as the clutch in your automatic tranny. It allows for slipping between the engine and tranny so you don't bark all 4 tires loose (or break something) when the car shifts. The slipping creates friction which generates alot of heat. The torque converter will "lock up" above a certain temperature (around 150 on my temp gauge) an speed (around 40-45mph) when the tranny is in drive - basically like disengaging (or is it engaging? - this damn wine in a box is messing with my head) the clutch - creating a solid/viscous lock between engine and transmission. In those conditions the tranny will actually start cooling down. For a technical explanation ask beav or do a web search.

Of course, I have to mention that all this is a band-aid for the real problem - this tranny produces alot of heat. From what I have read here the modification of the valve body by level 10 cures this ailment and eliminates the need for an aftermarket cooler altogether.

#15 01-29-2002, 05:39 PM

I am a newbie, SVX for 30 days, 122,000 miles and a factory rebuilt trans @ 110,000 miles. I have read the posts about B&M coolers but my tranny guy sez " no room." I have changed the fluid to RedLine synthetic and the filter but feel the need for further protection as I consider a mild turbo kit. Any help, pics appreciated.