T-Cooler sizing, too big? too little?

[spf_lexus]

Just built a hybrid 4.7 I call the 1.5uzfe, with a raised stall speed, expecting 9psi of boost on an ATI Procharger and expect 350RWHP-375RWHP on my stock R341E tranny and need to know if it's possible to run a T-cooler that's too large. I am getting ready to rebuild mine as it's got 210,000 miles and it's due. I will keep my TC as the fluid had no particles in it and no signs of wear. I plan on a rebuild kit + shift kit + T-Cooler. I see truck/hauling coolers with GVWR ratings for hauling and didn't know if I could overdo it.




I have dual 14'' electric fans and wanted to mount my cooler between the radiator and fan, so naturally wanted a 14''x11'' cooler I saw so that I could keep everything packaged nicely. I just don't want to "over-cool" mine and plan to run the stock radiator T-cooler after my aftermarket one in effort to keep the lowered temps within operating temps. Would this work using the stock cooler?



Any help appreciated

Sean

 

[StacytheBloke]

Hi,

I'm running one of these. (B&M are very big in motorsport particularly drag racing meaning they make quality components)

http://www.bmracing.com/PRODUCTS/Automatic-Transmission-SuperCoolers

this cooler has and inbuilt thermostatic bypass that ensures the atf comes up to optimal temp and stays there, no danger of over cooling.

You can also get thermostatic valves as an external item however that would clutter up a simple install.

Also they are made from pressed alumium, meaning they are really tough, (vital for my off road use)

Got mine off ebay, very reasonably priced.

Stacy

 

[spf_lexus]

Thanks Stacy, I was leaning towards the plate/fin type anyway so I'll do some homework on the B&M's, but do the these units have this bypass built into the cooler itself? Or is it somehing plumbed into the lines?

 

[Tonyd]

Hi Stacey,

Long time no hear, is your build finished yet?

I've got a transmission oil cooler within the end tank of my radiator, which means that in theory the engine water, engine oil (cooled by the factory engine oil to water cooler) and auto gearbox transmission fluid should all be at the same operating temperature as the water cools both engine and tranny oil.

My question regards the circulation of the transmission oil through the cooler? Is it pumped using normal gearbox pressure (which I assumed it was), or does it simply rely on convection?

Cheers,

Tony

 

[stevechumo]

The tranny cooler will definitely help with a limitation. The A341E will break at around 330-380 rwhp/rwtq. Mine already did after a week although I have an extra tranny cooler. A complete rebuilt tranny with hi-performance parts is required.

 

[spf_lexus]

Steve, where are you finding these parts? Been on the hunt for a week atraight and no dice. I was going to at least rebuild but refuse aftermarket rebuild kits, only toyota rebuild... and they run $900 in parts alone. I plan to be easy on her until X-mas break, then I will do something more permanent.

I did read about reybestos kevlar clutches but could not verify if they fit the a341e. Could barely find rebuild kits, just hope this 29,000gvwr cooler will prolong this thing a little. I had a full flush done at 200,000 and the fluid was cherry red and no signs whatsoever of metal/wear to speak of.

 

[stevechumo]

It's a secret. :laughing: I bought a complete overhaul kit from Alto. This kit is not for the OEM replacement, but it's a hi-performance kit instead. It's called Red Eagle kit. I also just talked to a local tranny mechanic and he seems to know what to do about this tranny. I'll take my tranny to him this weekend for him to rebuild it. He said he also could modify the valve body.

Don't spend the money on any OEM replacement. I guarantee a brand new OEM tranny will break with a little over 350 rwtq. Even an extra cooler won't help much. Itself alone is only good for towing or minor increase in torque. You're talking about nearly doubling the torque to 100%. I'll let you know how it'll turn out in a few weeks. My car only has 378 rwtq and it broke pretty much right away.

 

[gmacrae]

If you run the aftermarket trans cooler inline before the stock radiator cooler that will at least ensure the fluid passes thru the the stock cooling/heating system before it gets put back into the trans pan. So if for some reason your aftermarket cooler cools the fluid to below operating temp, the radiator cooler will bring the temp back up to where it should be. This will also reduce the amount of heat being put into the cars cooling system.