John Veninger

Maybe with a simple catch can, but it works with a good separator using a small return line to the pan. The cam towers on a 16V motor should not be used for venting or returns.
I have many DE's, and actual races with different setups to confirm it works.

Carl Fausett

We got back late from Blackhawk Farms Raceway last night - I do not have any data graphs or pics yet but will try to add them soon.

Blackhawk (for those who do not already know) is a 1.9 mile road course that runs CW with 6 right-handers including a small carosel, and 4 left-handers.

We ran 3 practice sessions and 4 timed races at 6 to 8 psi of boost with no oiling problems at all. I was/is ecstatic. I kept checking the dipstick and just could not believe it - after every practice session and after every race - my oil level on my stick never moved. I never added oil to it all day.

Ran out of gas on one event - pitchin' and gulping out of the corners - we put another 10 gallons in the tank and went back out. All toll, I put 15 gallons of gas thru it - but put it back on the trailer at then end of the day with the same amount of oil I came with! Very Happy.

I took 3rd place in my race group, and 10th overall of a 115 cars that raced.
The two cars that beat me were supercharged Mustang Cobras.

More info for those that want it:
>I was running 15w-40 Rotella motor oil.
>Only 450 miles on this motor, Hour meter says 5 hours - rings are still not quite all the way bedded in.
>The Accusump EPC is set to 40 psi... that means it will not add oil to my oil pan unless my oil pressure drops below 40. Hot motor (190+ deg oil temp) at idle I have 55 psi, more when I rev it (of course)
>I was actively downshifting before corners, but not engine-braking. I really did not change my driving style at all - I decided to just drive "normal" and let whatever happens happen.
>I carried my shifts to 6500 RPM or less.

Carl Fausett

I respect your expertise, John, you know that. But I want to say that Boosted is different. I raced my 928 for a year as a newbie and never had to even think about oil control. It never was an issue.

But boosted? Woah - a whole different ball game in controlling crankcase ventilation.

...and as Kevin Johnson and I have said elsewhere.... we SC 928 guys are not alone. You can log on to almost any forum and there will be threads ad libidum about pressuring the crankcase after SCing and what to do about it. I have read the SC Mustang forums, the SC Chevy forums, the SC Diesel racers forums - they all talk about it.

I think what IS unique to us is - that we take this problem under boost, and add it to the already rich discussion of 928 2-6 bearing and/or crankshaft failure, and it muddys the facts and the solution a bit.

GlenL

I recall my enthusiasm after trying my setup at Heartland park. That's 2.4mi and 14-18 turns depending on who's counting. I think the windage/foaming problem is related to 8+ second full power straights. Then bearing failure is hard stops and turns at the end of those runs.

I'm hoping you've got it solved.


What's "ad libidum" mean?

Carl Fausett

I agree with you, Glen, one event isn't much, its just all I have that I can report on today.
One SEASON without an oil prblem under boost - THAT will be something.

On the other hand, before these changes I couldn't even get one event done under boost without baby-sitting the catch can after every few laps.

Carl Fausett

Here is a clip of some race data from Saturday....

Note that:
> I was revving to 6500 RPM, with a peak of 6900 RPM
> we were regularly pulling 1.1 G's in the corners with a peak of 1.2 G's
> we were regularly hitting .7 G's braking
> and .4 G's in acceleration with a peak of .6 G Acceleration

Just wanted you to know I was throwing the oil around pretty good....

SwayBar

Carl, glad to hear your engine is behaving so far. As Glen found out, a really good test is running the car at Road America, and PCA Chicago is in town Labor Day Weekend; are you participating?

Dictionary.com is really easy to use:

http://dictionary.reference.com/search?q=ad+libidum

Carl Fausett

I spelled it with a 'd' instead of a 't'

ad libitum

adv : without advance preparation; "he spoke ad lib"

My next event with this car is "928's at the Autobahn" and is only 3 weeks away.

SwayBar

Sterling, I'm sure it's in this thread somewhere, but are you running the entire kit, or just a partial one? If it's partial, which pieces are you using?

mark kibort

the Evo that i race with (450rwhp 4x4) runs a couple of seconds faster than i do in my unmodified 928. however, when his waste gate stuck, i was running 1 second faster, but even before it blew he was running only .5 second faster. we were all running down the carrocel at 1.5gs braking near 1g.
according to his $10k motec data aquisition system.


MK

smiffypr

Can anyone twll me how much the Mann-Hummel Pro Vent costs?

Smiffy

John Veninger

928 Specialist sells the Mann-Hummel Pro Vent for $125.00
https://www.928gt.com/default5.htm

smiffypr

Thanks Kevin and John. As some of you know I have been experimenting with home-made oil separators, and the current experiment is quite similar to the Mann-Hummel thing. Hopefully I will get the current experimental one finished in time for a track-day this Saturday, but I probably won't. I did think that it might be more sensible to just buy the M-H thing than fabricate my own design, but at US$125 plus shipping (from US or Europe), I can probably get my own made in ally or ss for less money here in NZ.
Smiffy

Carl Fausett

I have a barely-used one (two races on it) that I'll sell for $50.

smiffypr

Carl, are you selling it because:
1) it just doesn't work
2) it can't take positive pressure
3) it doesn't have sufficient capacity?

If you included shipping to NZ for the $50, I would be interested.

Smiffy