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Using transmission cooling line in radiator for engine oil cooling

DTCMMLF

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Gentlemen. Checking on automatic transmission, the gurus say idle pressure can be from 20 to 50 psi and some pumps produce 100psi. Most v8 oil pumps that I am aware of produce 35 to maybe 70 psi max. Question is can one that has a 4 spd car use the trannie cooling lines in the radiator for engine oil cooling? I am checking with Champions tech folk to get a read on max pressure designed into their Aluminum radiators. Has anyone ever tried this? Can't be just me thinking this way!
 

silversedan

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i would think it would be too small flow wise. the transmission coolers have a lot smaller passages than the engine coolers I've seen.
 

DTCMMLF

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When you say smaller, I am guessing you are referencing the OD of the rubber lines connecting to the cooler. What is the ID of those lines? If it 3/8 or so, that is about the same size cooling line of my F150 trannie.... I have emailed Champion. We'll see what the 'Oracle' has to say. Thanks for your thoughts. I appreciate all comment and responses. Sometimes my gyros don't always spin up when throttled to max!!!!
 

NoCar340

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The stock transmission lines on muscle-era Chrysler products was 5/16", which I agree are a bit small for what you're attempting. The oil-cooler kit I bought for my non-E-body turbo project has hoses literally twice that size, but it replaces the oil filter with an adapter plate--literally all the engine oil goes through it before reaching the engine. Obviously want as much volume as possible in that situation.
It might be possible to route some of the oil through the radiator cooler, as sort of a bypass, but I can't think of a good take-off point to do so. The oil sender port seems an obvious answer, but left unrestricted there might be so much flow you'd potentially do the rest of you engine a real disservice. With some sort of flow restriction, the volume actually being cooled might not be enough to justify the effort. You'd almost have to route the outlet back to the pan; a return to a pressurized location would just result in no flow.
Another possibility would be coming off the back of a 90° filter adapter on the high side, then returning at the low side. The obvious downside to that is you've created a filter bypass allowing cool, but unfiltered, oil into the engine.

You're on the right track, though: A liquid-to-liquid heat exchanger is a ton more effective than liquid-to-air, and a sneaky, built-in one like that would be ideal.

One thing to consider: You don't want your oil at the same temperature as your coolant. There are recommendations regarding temperatures at which oil performs its best. I found the information years back, but if memory serves oil temps should be kept between about 225°-265°F. Too cold and you lose flow, as well as creating additional drag via pumping losses. Too hot and obviously the oil will break down more quickly. Based on the information I found, I decided to forego an oil cooler on both my drag-toy Valiant and my street-oriented Challenger. It did not change the plan to oil-cool the turbo engine. Compressors make a lot of heat.
 

DTCMMLF

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The stock transmission lines on muscle-era Chrysler products was 5/16", which I agree are a bit small for what you're attempting. The oil-cooler kit I bought for my non-E-body turbo project has hoses literally twice that size, but it replaces the oil filter with an adapter plate--literally all the engine oil goes through it before reaching the engine. Obviously want as much volume as possible in that situation.
It might be possible to route some of the oil through the radiator cooler, as sort of a bypass, but I can't think of a good take-off point to do so. The oil sender port seems an obvious answer, but left unrestricted there might be so much flow you'd potentially do the rest of you engine a real disservice. With some sort of flow restriction, the volume actually being cooled might not be enough to justify the effort. You'd almost have to route the outlet back to the pan; a return to a pressurized location would just result in no flow.
Another possibility would be coming off the back of a 90° filter adapter on the high side, then returning at the low side. The obvious downside to that is you've created a filter bypass allowing cool, but unfiltered, oil into the engine.

You're on the right track, though: A liquid-to-liquid heat exchanger is a ton more effective than liquid-to-air, and a sneaky, built-in one like that would be ideal.

One thing to consider: You don't want your oil at the same temperature as your coolant. There are recommendations regarding temperatures at which oil performs its best. I found the information years back, but if memory serves oil temps should be kept between about 225°-265°F. Too cold and you lose flow, as well as creating additional drag via pumping losses. Too hot and obviously the oil will break down more quickly. Based on the information I found, I decided to forego an oil cooler on both my drag-toy Valiant and my street-oriented Challenger. It did not change the plan to oil-cool the turbo engine. Compressors make a lot of heat.
Correct me I am wrong, reference BB, but my small blocks all have pipe threaded plugs in both the lifter galleys at the back of the block. I take mine out each time I get a block tanked for rebuild. Will eyeball my 440 tomorrow. Also, appreciate the oil temps as I did not know that, but if the thermostat is keeping the engine coolant temp at 190, not sure I am pushing the 230 rough average you mentioned. Anxiously awaiting Champion's response. And appreciate your thoughts. Always good to have another set of eyeballs and ears watching out for your engines health.
RBHawk....
 

NoCar340

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...if the thermostat is keeping the engine coolant temp at 190, not sure I am pushing the 230 rough average you mentioned...
Keep in mind, unlike the oil the coolant is not literally carrying the load and friction of engine bearings. The oil is in direct contact with almost everything that moves; the coolant is merely absorbing the heat through a cast-iron barrier. There are no cooling passages to the mains, rods, cam bearings, oil pump (which creates a lot of heat on its own), etc. so the oil runs much hotter than the coolant. How much hotter? Only a gauge can tell you for sure, but +40°-50° seems a pretty solid estimate.
 

silversedan

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When you say smaller, I am guessing you are referencing the OD of the rubber lines connecting to the cooler. What is the ID of those lines? If it 3/8 or so, that is about the same size cooling line of my F150 trannie.... I have emailed Champion. We'll see what the 'Oracle' has to say. Thanks for your thoughts. I appreciate all comment and responses. Sometimes my gyros don't always spin up when throttled to max!!!!
I was referring to the internal size of the cooler in the radiator, why would you want to put a restriction in oiling system of the motor? GM uses oil coolers on some trucks in the radiator tank but they are much larger than the trans coolers.
 
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