Man I fought that problem a few months back.
http://maliburacing.com/forum/viewtopic.php?f=2&t=78927
http://maliburacing.com/forum/viewtopic.php?f=2&t=78927
327mali said:theirs really only 2 reasons trans fluid comes out of the vent. A its over full.(it would have to be like 1 or 2 quarts over full for this to happen) and B your converter is going bad. i know you just said its a 4500 stall converter but #### happens and the converter could possibly going bad. as for the trans cooler not cooling enough that's absolutely wrong. a trans cooler that's 5x11 will cool 7x better then the radiator. and yours is 11x11. more then enough for a race car. only other thing i can think of is that your running like 2:97's in the rear and the converter doesn't ever lock up. but you would be a fool if you where running a race car with 2:97's with a 4500 stall converter
Malibuwagon80 said:I had this happen to me a while back. If you get up on the converter to hard it will push the dipstick up and fluid out. Get a hughes dipstick with the locking lever. You may be leaving at too high a rpm, are you loading the suspension? I've found I get my best 60's leaving at around 2k, its a 5k converter. Hope this helps!