Trans Cooler line size

[Mike67]

So I bought Hayden trans cooler with a fan. The line size is a 9/16 flare, I have 4an fitting in my case, would there be any issues with changing those to a 6an? Also the threads in the case appear to be straight, so I'm assuming that a 1/4" NPS is correct? Thanks

 

[R413]

The case threads are 1/8” pipe thread.

 

[wyrmrider]

you can install 1/4 npt in the case and drill the tailshaft when you rebuild the trans
if you put a pressure gauge on the trans output you will see that 1/2 inch hose is much less restrictive than 5/16 or even the later 3/8 tubing
Mopar went to 1/2 on the V10 and diesels for a reason
this is even more important with a loose converter for heat
and with the od trans to lube the thrustwashers in the od
there are other obvious mods

 

[Mike67]

you can install 1/4 npt in the case and drill the tailshaft when you rebuild the trans
if you put a pressure gauge on the trans output you will see that 1/2 inch hose is much less restrictive than 5/16 or even the later 3/8 tubing
Mopar went to 1/2 on the V10 and diesels for a reason
this is even more important with a loose converter for heat
and with the od trans to lube the thrustwashers in the od
there are other obvious mods

So I guess someone has already drilled the case for the 1/4, they are in the stock locations, not in the tail. The trans is already assembled and installed. Along with the cooler I've installed a Hughes deep pan as well.
I can get a 1/4" to 6an fitting, was just wondering if there would be an initial pressure drop going from the 1/4" to 3/8" (6an) and would it be a issue?
Thanks