How much oil is normally supposed to collect in catch can?

I’ve had my car on the road since last friday. 6 days and about 400km of average driving (not hard, not soft). Drained catchcan today and filled half a large timmies cup. Friend said that was ab-normal. Running Redline 10w30 in a basically stock SR that has great compression across the board. Going to do a leakdown test tommorow, but I’m not expecting it to be bad. Possibly running too thin an oil?

You might consider trying 15w30, I’ve heard of a lot of the SR guys in the states where it gets hot using the thicker oil, there’s some really good discussions about it on Fresh Alloy. I’d wait on the results of the leakdown test first though.

I’ve heard of some of the Honda guys running mad boost filling their catch can on 1 run down the dragstrip, but I don’t care what they say, that’s too much.

If the leakdown test checks out, I’d say try the 15w30, but only for another 2 months or so 'cause it’ll start cooling off after that…

My car has pretty much no blow-by, like, my catch can wasn’t worth having installed, so I removed it. I have a clear hose from the T on the valve cover to the intake pipe, and it’s still clear, after about 10,000KM. My car pulls a solid 18-20inHG, and runs at a consistent 8psi.

/sorry for the Aahmed post, my keyboard didn’t have a breathalyser tonight… :S

I’m running .5 bar right now, which is what, 7.35psi? Car pulls steady 500mm/hg at idle, too tired to do the conversion right now, but theres no wild fluctuations in the reading. If it does fail a leakdown check, I’m looking at rings/pistons right, since some of the compressed gasses are seeping past the piston into the crankcase causing pressure and lots of blow by right? (I’m kinda rusty, my current garage job we dont do much engine work, so I get kinda rusty on my engine problem diagnostics) Guy who had the car before me had less oil in the catchcan after 8 or 9 months of running than I’ve had in 6 days, and all I’ve added is a FMIC and a BOV. I’m hoping the shop foreman still has his leakdown tester stuffed into the back of his toolbox somewhere. My friend who is a VW tech and a turbo guy also reccomended 15w40 when I told him my story. Thanks for the reply

Well, technically you could clear it up with just rings, but if you’re in there anyway, some decent pistons might not be a bad idea. Plus if you throw in some ARP hardware with that, you’ll have your bottom end built :smiley:

Let us know what the leakdown test looks like.