924Board.org

ideola · Joined: 01 Oct 2004 Posts: 15550 Location: Spring Lake MI

Why is there no mention anywhere on this site of oil pan baffles??? Is there a mechanical reason that pan baffles can't be used on our cars? I'm specifically interested in the 931...so perhaps some of the turbo oil line plumbing is an issue?

This technique is used by all the big block guys here in Motown to prevent the crank from having to slosh thru the oil...which seems like a particularly good thing on a small 2L that uses 15W50 oil! I am planning to put a scraper in on the wide body project, but I'd like to know if there is any reason a baffle system in the pan wouldn't be advisable.

I understand that for some folks, the cost of having a custom baffle setup welded into the aluminum pan might be a deterrent...but at this point, I'm more interested in what the conceptual mechanical objections might be...
_________________
erstwhile owner of just about every 924 variant ever made

bass gt · Posted: Fri Aug 10, 2007 3:50 pm Post subject:

No objections at all!! I have the sumps in my race engines baffled.
Next up is a windage tray, to seperate the crank from the oil.
Do it, it makes sense

Steve
_________________
Front Wheel Drive is the Devil's work.

Cedric · Joined: 27 Aug 2004 Posts: 2806 Location: Sweden

I´ve got a scrapter in the turbo engine wich i´m building at the moment.

www.crank-scrapers.com/

He can help you with windage tray. He wanted to borrow my engine block to do the measuring but unfortunatley i´m at the other side of the atlantic. Ask him, hi might have it done by now. and for the baffels, the original pan isnt that bad. I havent had any problem with oil starvation. And i have done lots of laps on several race tracks on race rubber without any problems.
_________________
1980 924 Turbo
www.instagram.com/garagecedric/

924RACR · Posted: Fri Aug 10, 2007 9:12 pm Post subject:

As noted, the stock pan is very good in this regard - it's not a POS stamped steel bucket like the local stuff. That plus the crank scraper or windage tray, you're in pretty good shape - though I personally recommend an accusump for true race use.
_________________
Vaughan Scott
Webmeister
'79 924 #77 SCCA H Prod racecar
'82 931 Plat. Silver
#25 Hidari Firefly P2 sports prototype

ideola · Joined: 01 Oct 2004 Posts: 15550 Location: Spring Lake MI

Yeah, I've talked to the guys at Crank Scrapers, and I'm having them make a custom scraper. My crank has been stroked, and my rods are custom made as well, so I want the scraper profile to match precisely.

I have a friend who is a welder by trade. He has all kinds of metal stock available to him (most of which he won't charge me for), and he has MIG & TIG in his mobile setup, so I can have him do any sort of custom fabrication I need for less than union-scale hourly rates. I'll probably have him help me with the baffling.

The biggest bang-for-the-buck route seems to be scraper+baffles+accusump (VS, I was already planning to go with the 3-qt. Canton setup). A dry sump setup just seems to be too expensive ... by my estimates, a complete system would end up costing somewhere in the neighborhood of $2500.

However, Kevin Johnson @ Crank Scrapers recommended that I investigate a "Racing Vacuum Pump" available from GZ Motorsports. Based on what I've read, these units increase the atmospheric vacuum in the crankcase, which is theoretically beneficial for a high-boost application like mine. The cost appears to be about half that of a dry sump, but about double the scraper-baffle-accusump approach. Any opinions on this approach???
_________________
erstwhile owner of just about every 924 variant ever made

Min

ideola · Joined: 01 Oct 2004 Posts: 15550 Location: Spring Lake MI

Min

Smoothie · Posted: Sat Aug 11, 2007 11:40 am Post subject:

Interesting concept (sprayers), but something's telling me that they'd be a lot of extra work and complication (or are they something that just fits in place of the squirters that're already there?). Detonation and other piston stressors would be much more effectively handled from the other side with intercooling, water injection, high octane, correct timing, etc., right?
_________________
"..it's made in Germany. You know the Germans always make good stuff."

'82 924T, US version, dark green metallic, 5 speed Audi 016G gearbox

Lizard · Posted: Sat Aug 11, 2007 1:53 pm Post subject:

I wouldnt bother with the squirters, they cause airation problems,

I also wouldnt bother dry sumping the 924 engine as it doesnt have the rod bearing issues the 944/928 engines have.
_________________
3 928s,

Min · Posted: Sat Aug 11, 2007 1:57 pm Post subject:

Smoothie · Posted: Sat Aug 11, 2007 4:00 pm Post subject:

Min · Posted: Sun Aug 12, 2007 7:03 am Post subject:

ya, I knew those were there, however, I'd be concerned about the amount of fluid they are actually sending at the piston. I'd be interested to know.

Min
_________________
Custom means it didn't come from a box.
1980 n/a with EDIS and Megasquirt II Injection. 7 different colors and counting.

Min · Posted: Sun Aug 12, 2007 7:04 am Post subject:

oh, and on the rebuild I just did, they were plugged full of carbon on all rods. I had to clean them out.

Min
_________________
Custom means it didn't come from a box.
1980 n/a with EDIS and Megasquirt II Injection. 7 different colors and counting.

Smoothie · Posted: Sun Aug 12, 2007 7:49 am Post subject:

Very good point, then they should be cleaned out whenever possible - when rebuilding or just replacing the con rod bearings from the bottom..

Another thing occurs to me - that those squirters would probably only give one quick squirt per revolution (spm's = rpm's

) as the hole in the cranks' con rod journal passes the hole in the con rod, right?
_________________
"..it's made in Germany. You know the Germans always make good stuff."

'82 924T, US version, dark green metallic, 5 speed Audi 016G gearbox