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spuggy spuggy is offline
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Join Date: Jul 2003
Location: Glorious Pac NW
Posts: 2,828
Originally Posted by sand_man View Post
I never idle it. As soon as I turn the key, away we go. *HOWEVER*, I NEVER boost a cold engine. I normally wait about ten to fifteen minutes...or until the oil temp needle is at the top of the first block on the bottom of the gauge.
Sorry, what tempurature would that be, roughly? My gauge is numbered and doesn't look like that...

I stay around 3,000 RPM maximum until oil temp reaches 125 (I think - it's the unnumbered tick between 80 and 170 on my gauge), then I'll rev to 4,000 - but still carefully avoiding boost at this point.

I'll boost once the oil gets a little over 170 - which, with a FMOC, is about as high as it might get without boost on a cool day anyway...

As for cool down, I'm normally able to slowly cruise a few blocks through my enighborhood, and then it idles for a few moments in the garage while I have a peak undermeath the engine.
Yeh, the nearest place to my house I can boost is a good 5 miles away, so I don't sweat the cool down much, even without a turbo timer circuit..

Although I have seen someone say they run the motor up a little (i.e. 1400 RPM or so) just before shutdown to ensure the turbo scavenge pump clears any additional oil.

Originally Posted by bkreigsr
I just let it sit long enough to get out and close the garage door, then get back in and head out.
Revs stay between 2,000 and 3,000 until the oil gets to 170 deg.
Both you guys raise something that interested me, the topic of driving off almost immediately - and instrumentation differences...

NathanUK said in another post that oil pressures are limited to 5 bar. All the photos I've seen of the "druck" pressure gauges calibrated in bar, they look like they ONLY read as high as 5 - is this correct?

See, my oil pressure gauge reads up to 120 PSI (8 bar)... When I initially start the motor, I run it @ 2000 RPM (for good oil flow). Oil pressure reads 100 PSI (6.7 bar). A little more RPM will make the gauge read higher - it definately isn't limited...

PO told me to be careful not to run up the pressure too high in this stage.

After a few seconds (maybe 15-20, maybe a little longer, say, 30 if it's really cold), the oil pressure will blip downwards to 75-80 PSI or so for the first time - I believe this is the internal engine thermostat opening and returning the hot oil in the case.

After another 20-30 seconds, you start to see a succession of downward blips - I normally wait for 3-4 very close together (5-6 seconds) and then select gear and prepare to pull away.

If I sat there and continued to run @ 2000 RPM, about another 10-20 seconds would probably be enough that the oil pressure would be a constant 75-80 PSI (i.e. the engine thermostat was completely open, because any oil entering the motor gets hot enough on the way through to keep it open).

I'm pretty sure that running the motor up to 3,000 RPM in the first minute of starting it would create pressures that would exceed the ability of my 8 bar pressure gauge to display it. Just thought I'd mention that...
'77 S with '78 930 power and a few other things.
Old 11-08-2007, 07:49 AM
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