LS1 Questions

[86tank]

Asking this for lay. On his motor he had all the breather and vacuum lines ran like they where supposed to be factory. Whenever it would get off camber it would start smoking pretty bad and then we had somebody (can't remember who it was) tell him that it would do that if they where ran like factory. Now when you get the motor in a higher rpm range it is blowing oil from somewhere under or around the intake. Don't know if the routing of the breather lines has anything to do with that but when we changed the routing of them. So anybody got any ideas on where to look on how to route all the breather and vacuum lines or done this to a ls1? Just tryin to see if anybody else has ran into anything like this.

 

[wizzo]

the smoking most likely is oil from pcv system going back into the intake via the vacuum line. i ran mine through a "catch can" then back to the intake that way you still get the vacuum for crank case ventilation but you keep oil from getting back to the intake.

oil at high rpms, could it be valve cover gaskets? i had an issue with mine pushing oil out around the dipstick while we were dyno tuning it. we took the pcv and opened up the hole in the bottom of it and the oil leak went away.

 

[1TONZR2]

here is my system....got the idea from Wyatt.



works great and never smokes.

Brian

 

[patooyee]

I just wrapped my vent line around an intake tube 3 times to form several loops. The most oil that can ever make it into the intake that way is one loop's worth. If I roll completely upside down it will smoke for about 30 seconds after I right the rig. It doesn't matter how long I leave it upside down for because only one loop can fall in. I have no issues in any other circumstance.

There are valleys and crevices inside the intake where oil can get trapped for periods of time and then finally get drawn in either by lots of vacuum (high throttle) or tilting side to side / forward, back.

 

[lay]

So the question I have now is. Don't run them to the intake and run it thur a catch can and block off the intake ports?? Or run them to the intake with a catch can???

 

[crawlin85cj]

I've been going a little more simple with good results. I added a good PVC from a gen1 SBC with the valve covers oriented with the PVC in the front. Rather than an oil cap I used a breather. It seemed to work pretty well.

The famed and patent pending Wyatt method is about as sure fire as can be not to allow oil into the intake if you have the room to plumb it in.

 

[wizzo]

So the question I have now is. Don't run them to the intake and run it thur a catch can and block off the intake ports?? Or run them to the intake with a catch can???

run the pcv to the catch can then to the intake