[Fot] valve cover venting

[Jack W. Drews]

The major hot rod suppliers sell a kit for this. It includes a pair 
of pipes to weld into your exhaust headers, two one-way valves to 
prevent backfires from blowing off your valve cover, and some misc 
parts. Real cheap at something like $50..

I did this early on in my vintage career and when I mentioned it on 
the net I got royally flamed. It's against the SCCA rules. I could 
never understand the objection - after all, if you blow an engine, 
you put the oil directly on the track. I never saw oil coming out of 
my tailpipe. I took mine off - Joe left his on and continues to leak 
less oil with the kit than without.

More substantive info, however, comes from my local speed shop. They 
run a NHRA national championship engine and do a lot of dyno work. 
They recently tested two systems that do this. One system uses a GM 
air pump and pulls a negative pressure -- on their engine it added 20 
hp to a 500 hp engine. That kit is commercially available for about 
$500. They also tried the exhaust-sucked system and found it added no hp.

I still like it, though. Data be damned.

uncle jack