Now that I have a plan to tackle the fuel heating issue, it's time to come up with a plan for the other thing that's bothering me.
My catch can breather puffs smoke (vapor?) at hot idle. It's not a ton, but because the breather is sitting right at the corner of the hood, it's visible when the car isn't moving. That annoys me.
It's my understanding that some vapor from the catch can is nothing to worry about. I have a 1/4" of fluid on the bottom on the can. That is with about 200 miles and a few dyno pulls. I would be more concerned if the can was full, but I couldn't believe how little is in there.
I think the visible vapor is a combination of having 3 breather lines (one from each valve cover and one from the lower intake) as well as those lines being very short. Most guys have longer lines so that vapor gets a chance to settle along the lines and turn to liquid before it hits the breather.
My plan is basically to take the line from the lower intake and run it into the exhaust using a scavenging kit. The lines from the valve covers will still go to the vented catch can, but the third line will dump into the exhaust instead of going to the can like it does now. The scavenging line is supposed to pull about 3in of vacuum. Will my exhaust have enough airflow at idle to pull a vacuum through that line? I guess I'll have to try it to find out. From what I have researched, the crankcase would benefit from a little extra vacuum. A check valve will be used on the scavenging line to prevent exhaust backpressure at high rpm from pressurizing the crankcase.
This is all assuming that the lower intake line is the one pumping out the most vapor. I need to disconnect it from the breather first to find out.
Or am overcomplicating all this? Should I just disconnect the line from the lower intake and cap both ends and let the lines from each valve cover do their thing? Maybe my idea of three vent lines is just causing more trouble than its worth. The curious part of me still wants to see if scavenging the crankcase via the exhaust if effective on my setup.