Hi guys,
On my '89 with the 727 auto, I have the factory water cooler on the side of the block, and the factory one up front at the radiator. Is this enough for weekend warrior drag racing? Do I need to add in a 3rd cooler with a fan, or would a deep trans pan be a better choice? I wasn't sure how well the stock coolers worked.

Also, my owners manual doesn't show the cooler up front at the radiator, only the one on the side of the block. Is the front one part of an add on for a tow package or something?

Thanks,
Jason

 

Don't know the 89 models that well... but the front tranny cooler is usually added as part of the towing package!

My Mag Hy-Tec Deep Dish Pan adds 4 qts and helps a lot to kep thinks cool, IMO.

RJ

 

I would go with an addon cooler with a fan. Think of drag racing the same as towing. Your most likely to be trying boosted launchs. That builds heat fast in a converter. With little air flow threw the front cooler. You could overheat the trans.

Rig the fan controll on a toggle switch. Let the egnie idle in netural for a while after each run to cool everthing down.

 

2nd RowJ ..

Deep pan will give you better cooling. And it was fun at the trans shop after they installed my 47RH telling them I needed 4 1/2 gallons of trans fluid.....
I've noticed that I can place my hand on the pan ( checking for leaks ) after driving it somewhat hard where before I couldn't.
I installed a trans cooler behind the grille to replace the 'cooler' thingy they have in there...It does require you cut the grille inserts in half ( on my '93 ) but I think it's worth it..

 

I think it would be enough because lets say you boost launch so your sitting at the lights you wait for lights to change for a max of 10 Seconds if that, once you launch your going to have air flow and a 1\4 mile or 1\8 mile your shutting down pulling back around and shutting the truck off or leaving Idle so i don't think it will be to bad, Best thing to do is to get a trans gauge and just watch it. try it with out and then if it gets to hot you know you need extra.

 

It's been my experience that a 100* increase in transmission fluid temp equates to approx .10 seconds longer ET (in the 1/8th mile).

If you're into boosted launches, learn how that particular Christmas tree works. At Dunn-Benson for example, the blue light at the top of the tree, if it's flashing, those in control aren't ready. I typically just pre-stage until the blue light goes steady. Having seen that, I'll inch forward tripping the second set of staging lights building boost as as soon as I can knowing the race is fixing to be on.

Sitting there with full race boost waiting on the other driver will lose the race for you. The fluid in the converter is getting hot VERY fast. Hot, thin trans fluid won't hook-up as well as cooler, thicker fluid will.

Further, it's been my experience that a fan assisted cooler will substantially out perform the OEM cooler up front when it comes to cooling things down after a pass.

NOTE!! Be sure to have your truck in neutral when cooling things off after a pass as putting it in park stops the flow of fluid through the transmission.

For racing purposes, one would do well to pinch closed one of the engine coolant hoses that feeds the heat exchanger under the manifold.

In my opinion of course.

 

You think the cooler on the block really heats it up more than it cools? Obviously, the best setup would be a deep trans pan and a extra cooler, but this is supposed to be a budget build for weekend fun. So I'm thinking of going with one or the other. I do plan to install a converter before I go really run it hard, as I know the stocker really heats things up being loose as it is. I figure that would be about the best $300ish bucks I can spend related to the tranny.

Jason

 

With the way the stock/OEM heat exchanger is plumbed to the water that's pretty-much circulating at the water pump, you're not gonna cool the trans fluid any cooler than the engine coolant coming from the radiator.

While it doesn't necessarily heat the trans fluid to the actual engine temperature, the heat exchanger is meant more to bring the trans fluid up to a minimum temperature when it's really cold outside. (Obviously, if the trans fluid goes above the engine coolant temp, then yes the heat exchanger cools the trans fluid.

Again, just pinch closed one of the two coolant hoses to stop the exchanger from adding heat during racing.


Again, no matter what you mod, when racing, idle the engine with the trans in neutral to keep the trans fluid moving through the plumbing (and to the cooler) when cooling things down after a pass..

 

On our old 91 we took the cooler off the block and just had the stock cooler up front,the trans temp never got over 170* on a run (1/4 mile). what do you plan on run in the 1/4 with your truck

 

Hopefully 13's. I don't plan on spending a huge amount of $$ on it, but I know 13's is within reach. Maybe I'll splice in a quarter turn valve inline to the cooler on the block so I can shut it off. Thanks for the tip on the idling in nuetral.

So trans pan or cooler? How about everyone cast their vote for one or the other...


Jason

 

My vote will be for a pan, holds more fluid and will cool at same time,

 

Yep, more fluid the better. Cheap, easy insurance. Worst case scenario it'll take longer to heat up. Go longer between changes, too.

 

Well, I reckon I'll be the stick in the mud and vote for the cooler.

(NOTE: The following numbers are off the top of my head therefore out of reach of the digits on my hands and feet).

- Having simply more fluid does not equate to more cooling effect.

When it comes to heat transfer between two things, in this case, hot fluid to cooler air (heat always moves to the cooler object), of the numerous facets effecting such, . . .

- The difference between a standard pan, and say a unit with four quarts additional capacity, amounts to the additional metal involved in making the pan deeper. For our discussion let's imagine the pan is 12" square. For our discussion let's say we can accomplish the additional capacity by making the pan 2" deeper.
- The four 12" sides adds up to 48". Making it 2" deeper means we're adding 96 square inches of surface area to the pan.


Now let's consider what might be the more commonly seen remote cooler with a fan. For the sake of our discussion, let's say it is a six-pass cooler using 1/2" OD pipe in an 8" x 10" x 1" finned assembly.

- If one were to straighten all the pipe, split it down one side, and unroll the pipe so as to make a single strip of metal we might have (again for the sake of easy discussion) a 1" wide strip that's about 70" long (six at 10" plus five U-bends at a conservative 2" long)


With comparing the surfaces areas thus far, we have approx 96sq/in for the pan vs the 70sq/in of the cooler's pipe.

Now add all the added surface area afforded the cooler with the addition of the fins. Figure perhaps 10 fins per inch of cooler. that's about 10" at 10 fins per inch or 800 sq/in.

That comes to roughly 870sq/in of surface area (8" x 10" x 1" finned assembly) compared to the 96sq/in of the pan.

That's a BIG difference in the world of thermal dynamics as the exchange of heat is by way of the surface area..

Also consider that the thickness of the metal effects the heat transfer rate. The typical aluminum pan is much thicker at the point of fluid to air transfer as compared to the thinner pipe. This is skewed even more by the fact that most of the coolers run copper pipe which thermally conducts heat better than a comparable unit of aluminum.


IMO, you'll get a much better bang for the buck with a cooler.



So say the voices.


Yes, I've been drinking tonight.

 

I am with BC on this one. Go external cooler with a fan and manual control of it.

 

sometimes i think we spend waaaaay to much time thinking of this stuff! no wonder my girlfriend thinks wer'e all nuts!