Relocating/Replacing CDR with Catch Can

[renjaminfrankln]

I cut down my 1st gen banks airbox on Saturday. Replacing the air filter with a cone style. I need to either fit the CDR on to a 3.5" aluminum pipe somehow, or I can use a catch can setup that was given to me by a friend. The catch can is intended for a smaller diesel, and I may be bottlenecked by 1/2" NPT threads. I was thinking I could use 5/8 heater hose and get some 5/8 barbs to 1/2" npt for the connections.

My question, is 1/2" NPT too small? I do not want to pressurize the crankcase and blow seals.

 

[The_Josh_Bear]

I cant say 1/2" is too small, but it sure has a much bigger chance of being inadequate. The area of a .5" tube is 4 times smaller than the same length 1" tube.

These engine have lots of blow by unless you run smaller ring gaps on the pistons. 3/4 NPT might be the way to go for oil rated hose and adequate flow volume.

Which brings up the heater hose-- exposed to oil vapor it WILL degrade over time. You might get a couple years out of it or better but it will fail. So that's your call, I went through all this recently with my charge air cooler install.

Oh and probably most importantly: whatever cone you're getting, make sure its awesome and big. I got a temp cone to get on the road for the fall and it was so restrictive that my entire charge air cooler setup was nearly pointless power-wise as the engine was starved.
Fast forward to installing a Big Honkin Air Filter and its WAY better. Totally worth it. And that's sucking hot air from under the hood, the stock cool air snorkel works great on the Ford/ATS setup, I don't know what your banks setup is like.

 

[Thewespaul]

1/2 is the minimum you can get away with, larger the better. Don’t use heater hose it will degrade in no time, I will be using -12 an oil lines on my catch can setup once the valve covers are finished being built.

 

[renjaminfrankln]

Duh, thanks for the reminders on the hose. I will make sure whatever I use is oil rated.

3/4" hose to 1/2"NPT male barb is going to be the most restrictive part.