I don't know enough about transmissions to know better, but can I swap out the steel cooler lines with something a bit bigger in diameter for improved flow to the cooler? I was thinking something in braided staniless, that I can route away from the headers and along the frame rail to the cooler and back. Pros and Cons appreciated. As well as suggestions for which lines to use, since I think you are not supposed to use fuel-grade hose.
250 psi??? Are you serious? I have been running rubber fuel line for the last half of mine into and out of the cooler for the past 5 years. One of the lines bent and rubbed on something (I don't remember what, pulley, maybe?) and rubbed a hole in the metal line, so I cut it off and hoseclamped 3/8 or 7/16 fuel line in place. I KNOW fuel line is not rated for anything near 250 psi! I can get efi braided line, if someone doesn't chime in and say that the trans fluid will eat it up. I used to have several feet of braided NOS line, which was a solid plastic lined with the braided stainless. It was probably rated pretty high.
I think the orifices in the case where the lines connect are too small for that to make a difference, unfortunately. Unless perhaps the bigger lines will slow down the flow through your trans cooler and maybe that will help...
I was thinking about the orfice sizes also. I am also thinking about the heat. I suspect the line coming out of the trans will be pretty hot. My opinion is that I would rather have less rubber hose as possible. I wish I had my origional steel lines as they came from the factory myself. Only 4 connections and no rubber to blow.
Hmmm.... Good points. I still have most of the steel line, just the last 8" before and after the cooler is rubber. I don't know at this point, but I gotta figure it out over the next couple of weeks.
My lines have been 100% rubber for some time now. I put brass barb fittings in the trans and ran I think it was 5/16" trans cooler line, maybe even 3/8". My steel lines were mangled, and my reasoning was I wanted as few connections as possible since I only run an external cooler and they had to be rubber at that point to connect to it anyway. I may eventually go back to steel, I never intended for this arrangement to be permanent, but so far it's not given me the slightest bit of trouble and I drive it every day. My trans temp gauge has never gone over 200 even in the most extreme conditions. (3 hr drive in 95+ heat) Usually it's about 160-180. I also have a deep finned aluminum pan, so that might make a difference.
I would say that the use of proper type hose is key to longevity. My luck is it would rupture or split while I was showing off lol. Knowing the temp probobly gives some ease to the tension of the unknown.
Yeah, I wouldn't have used anything but "transmission cooler hose." Auto Zone and O'Reilly both sell it by the foot. (I know 'cause I had to go both places to get enough of it!)
NAFORD got me hooked on using braided. It just looks so much more professional that what my bended tubing would end up looking like...