oil pressure.. Dry sump. - Page 3

*gaboonviper85* · 11-05-2009, 09:55 PM

Quote:

Originally Posted by IJ.

Would if they were genuine Clevite 77's

(you really need to stop stating things as absolute Goon)

The holes are open at idle when the pump is struggling to maintain pressure and they do make a difference.

I don't mean to state it as fact....I mean to question how that is possible...in my head I can't see it happening without tacking the oil system itself...if it does effect pressures then is it in a good way (more flow) or bad way (something chokeing flow)...

Although I honestly don't see how clevites would increase psi...maybe reduce psi but improve flow...so if you care can you explain how a bearing (clearanced properly) will increase pressure without hindering flow...

*wiseco7mgt* · 11-06-2009, 02:35 AM

Really i think the whole issue is the squirters and the remote filter setup, just as Ian confirmed. Yes i did use clevite 77 bearings from suprarich back in late 2006 for the build. Any doubts of me giving dodgy numbers i can make a vid for you of my rpm and autometer pressure gauge.
Don't forget this whole thread was to benefit people who were interested in a dry sump setup and maybe we need to get on topic as this idea interests me as well for future projects. Has anyone built a dry sump for there 7m? and if not what is required?.

**IJ.** · 11-06-2009, 02:53 AM

Quote:

Originally Posted by gaboonviper85

I don't mean to state it as fact....I mean to question how that is possible...in my head I can't see it happening without tacking the oil system itself...if it does effect pressures then is it in a good way (more flow) or bad way (something chokeing flow)...

Although I honestly don't see how clevites would increase psi...maybe reduce psi but improve flow...so if you care can you explain how a bearing (clearanced properly) will increase pressure without hindering flow...

Genuine 77's aren't round so even if you clearence them correctly they're going to leak more Oil than a regular bearing.

It's a Moot point as Clevite don't make 7M bearings these days.
(the egg shaped bore is what makes them desirable as it promotes an Oil wedge to form when the crankpin is unloaded)

gary_808 · 11-07-2009, 04:04 PM

Quote:

Originally Posted by wiseco7mgt

Really i think the whole issue is the squirters and the remote filter setup, just as Ian confirmed. Yes i did use clevite 77 bearings from suprarich back in late 2006 for the build. Any doubts of me giving dodgy numbers i can make a vid for you of my rpm and autometer pressure gauge.
Don't forget this whole thread was to benefit people who were interested in a dry sump setup and maybe we need to get on topic as this idea interests me as well for future projects. Has anyone built a dry sump for there 7m? and if not what is required?.

I dont think they have works realy well took bout 15 mins to make il get the pics up soon

***suprarich*** · 11-10-2009, 04:34 PM

For a dry sump system, you can adjust the pressure by using and external oil pressure regulator. Making a bolt on dry sump system for a mk3 with a 7m is on my to-do list for future SIP products. Don't use these fiqures for your street car, but Gary runs 85 psi of oil pressure on his dry sump system on the Malta Dragster. His motor uses a very large oil clearance, thus the need for pumping so much oil, to which hi psi is the secondary effect.

IJ is more than right about the aftermarket rods changing your oil pressure. The oil feeding through the crank comes out of the big end of the rod. So aftermarket rods have different big end widths, which makes a tighter rod side wall to journal side wall clearance than others. Smaller big end width means the oil comes out of the bearing more easily.