ehall

I like the sump question. Consider this a "sump bump". I'd also like to know about how the sump thig works, byt that I mean in for example, racing engines with an extra custom (dry or wet?) sump system. I get the purpose, I think, which would be to ensure continual lubing of the bearings at high rev/ hard cornering, but what's the diff, and what is considered the optimal set up if you had the need/cash?

ehall

Also in additon to the turbo question can someone explain "trim". (okay smart asses, not that kind! The kind in a turbo!)

Oh and thanks for the Corky Bell book tip. That will be purchased tonight.

Jeremy Himsel

Our cars are not dry sumps, the new ZO6's are and they involve a remote oil tank, evacuation system etc. Read up on the new ZO6 as some of the articles I've read about them all have better explantions of a dry sump then I have the time to write. You could always google it like Danno........

Rob 3

Dry Sump vs. Wet Sump.
A wet sump is what a typical sedan engine has. Its a deep pan that collects the oil as it runs through and down the engine with the pickup from the internal pump immersed in the oil in the pan, thus a wet sump.
A dry sump system runs a shallower or shorter oil pan with a specific location for oil collection and an external pump to scavenge the oil from the collection area which is then pumped into a separate container, often with a baffel in the container to help prevent aeration or oil foaming, definitely a bad thing. The external pump also pumps the oil from the separate container back into the engine from the collector or container thus giving a constant supply of oil at the proper pressure.
There are a couple advantages for a dry sump, one is help prevent the afore mentioned aeration of the oil, another is a lower mounting of the engine in the chassis of the car giving a lower center of gravity and theoretically, better handling. The engine can sit lower because the collector of the oil at the bottom of the engine needs only just enough clearance for the rods on the crank since the pan no longer needs to be the repository of the oil volume for the engine, so the crank centerline can be lowered closer to the ground. And if the oil isn't there for the rods to smash into, you don't beat it into a foamy frenzy. Dry sumps also help prevent oil starvation in high G situations. A wet sump, or having the oil pickup in the resevoir of oil in a typical oil pan, if unbaffeled, can alloy oil to wash away from the pick up in high G conditions, this gives momentary oil starvation, which can ruin the engine.
I just wish I was more organized in my explanation, but I hope this helps.
And I don not believe the sumps in the 951 are a dry sump system.

DDP

Jeremy, I would really like to know when Danno googled some info. How do you know this? And when did this happen? Thanks

Jeremy Himsel

There have been several times in the past where he's posted things as his own that I've read elsewhere. Sorry but I didn't keep notes of each instance. It really just made me laugh, especially when people post back on how smart he is because he posted it and they thought it was his own "original" idea. Plagerism at its finest.

Here, Chris Prack caught him as well....

https://rennlist.com/forums/showthre...ht=chris+prack

zerMATT951

I'm not entering into the Danno vs John debate, I'm sure they are both very capable "tuners", but when I clicked your link above and read the thread, there were no posts whatsoever by Danno. Your message above indicates that Danno was caught plagiarizing, where is that example? I'm a curious guy and would like to be enlightened... there are implications that "someone" (no names were mentioned) was "looking at" John's chips... nothing else.

APKhaos

Back to our scheduled programming..........dumb questions follow:

After the rebuild, I filled the PS system with generic PS fluid. Turns out that was a good thing, because there was some residual parts washing fluid in the system, and the fluid is contaminated. Need to drain it.
- there is a banjo bolt union at the bottom of the rack. Will opening this drain all the fluid?
- the owners manual specifies Dexron ATF - good old hydraulic fluid, not specific power steering fluid. I guess this is right, so what's the difference [if any] between PS fluid and AT fluid??

Porsche-O-Phile

I'd use what's specified. I don't remember where I heard this but supposedly ATF helps to enlarge / swell rubber seals, which is always useful on our leak-prone power steering systems. Personally I'd just assume ditch mine and go manual, but that'll be a later project. . . Anything that makes the underside of my car gooey must die.

APKhaos

Jeff,
After pushing the carcass around without an engine for a few weeks, and loading it on and off the trailer with manual steering and a small wheel, I'm loving the PS all over again!

I'm surprised how good the 951 PS is on the track. It was one thing I thought would have to go, but its definitely a keeper. No major leak problems yet - so far, so good.

ehall

There is nothing in my thread that says "Pleases start another Danno pissing contest." Take your crap somewhere else, like to one of the other three Danno pissing contests. Jeremy answered a related topical question, and made a comment. If you want to respond to the comment PM him. Otherwise keep that crap on some other (ie...your own) thread. Thank you.

Now, thanks for the sump info. That makes a good bit of sense.For racing it really makes sense, as opposed to a street app. where it would, under normal conditions, be overkill. The info on PS is also good to know. I had the belt get wet one cold night, in a parking lot, so I can't imagine driving one of these tanks without.

special tool

Wudn me

ehall

"Wudn me"

Nope.

Matt H

With the manual rack they are actually not bad to drive without PS. With the power rack and no fluid they are very difficult to get moving, once moving they drive pretty well.

Converting to manual can be done for a few hundred dollars.
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Bengt Sweden

Almost correct. The pressure actually increases much more due to the temperature increase. The pressure increase is proportional to the CR raised to 1.25. If it was only air and if there was no heat exchange with the surroundings the pressure would be proportional to CR raised to 1.4.
If all the heat was dissipated to the surroundings to achieve the initial temperature, the original statement would be correct (provided 100%VE).
Sorry to complicate things.
Bengt