[s-cars] Oil and Turbos

[djdawson2 at aol.com]

 Manny,
The cooler I bought (Summit) had mounting tabs on it that worked nicely for the old IC location.  I think I used one original mount point, and drilled the second.  On the outboard side of the cooler, I just made one small mount out of flat stock to keep it from bouncing, although it was pretty secure just using the 2 inboard points.

I ran the oil lines along the same path as the wiper fluid hoses... I used wire ties, and insulated using strips of silicon pressure hose to keep the SS lines from rubbing anything else.

All in all, it was an easy project that took little time to complete.  It also added about a quart to the overall system capacity, which was helpful as well.  I've had it for a good 4 years... no problems ever.

Dave


 


 

-----Original Message-----
From: Manuel Sanchez <manuelsanchez at starpower.net>
To: Scott Justusson <qshipq at aol.com>; djdawson2 at aol.com; audi list <s-car-list at audifans.com>
Cc: Tom Green <trgreen at comcast.net>
Sent: Wed, 25 Mar 2009 6:31 am
Subject: Re: Oil and Turbos









Thanks for the info Scott. 
 

Dave when you mounted your cooler in the old IC location did you use any of the stock mounting bits or did you have to fab up all the brackets? How did you route the new oil lines? 
 


Regards, 
 

-Manny 
 

95.5 ur S6 Avant (mostly RS2'd) 
 

On Mar 24, 2009, at 10:44 PM, Scott Justusson wrote: 
 

> 

> Audi wrote the book on all this 
turbo/oil stuff, specifically 

> co/authored many SAE papers on the subject, before and after > watercooled 

> turbos/synthetic oils. Specific to this topic ---  See 880258 "The 

> development of a Severe Turbocharger Bench Engine Test" and 860103 > "The 

> third-Generation Turbocharged Engine for the Audi 5000 CS and 5000CS 

> Quattro", and 970922 "Development of Modern Engine Lubrication > Systems". 

> 

> 

> Relevant Info to this thread: 

> 

> 860103 - Running I5 turbo motor, the temps of the piston ring with 

> watercooling are 190C, temps of the turbo bearing housing 120C. 

> Shutdown kills engines if the water circulation circuit is not 

> functioning.  Without water cooling the numbers are 260C PR and 140C 

> TBH.  On shut down, the non water cooled temps go to 360C PR and > 250TBH 

> within 2 minutes of heat soak. 

> 

> Rule:  Make sure your after run pump is working.  Regardless, some 

> idling before shutdown never hurts. 

> 

> Manny, leakdown of </=10% is good, =/>20% is bad.  Do compression > check 

> first.  IME, the 25 row oil cooler is a good match for the I5 > 20vt.  At 

> 90+F track day running an S car hard with a 25 row cooler, I > observed a 

> peak of 120C, and by the time we got to back into the pits the temp > was 

> at or under 100C.  For a dedicated track car a 36 row is better, but 


> overkill (read tough to get up to 100C) for daily driving.  > Altitude and 

> an FMIC, might be better with the 36 row, but that's a big dog to > stuff 

> under the hood of the dog house. 

> 

> Specific to the concerns on oil temps in other cars, the rule of thumb 

> is you want the oil temp to reach 100C to burn off the moisture in the 

> oil.  Since all Audi turbo cars come with 100C oil cooler thermostats 

> from the factory, this should be a non issue on the AAN. 

> 

> HTH and my .02 

> 

> Scott J 

> 

> 

> -----Original Message----- 

> From: s-car-list-bounces at audifans.com 

> [mailto:s-car-list-bounces at audifans.com] On Behalf Of Tom Green 

> Sent: Tuesday, March 24, 2009 7:15 PM 

> To: djdawson2 at aol.com 

> Cc: manuelsanchez at starpower.net; s-car-list at audifans.com 

> Subject: Re: [s-cars] Oil Temperature 

> 

> I just know better than to touch any of this stuff when it's hot. 

> But, I am sure that the oil temps are high enough to coke conventional 

> oil at 150ºC, and at that inlet temperature, it would be hotter in the 

> turbo.  What was engineered to work just fine for 50K miles is 

> not necessarily just fine at 150K miles.  The advantages of synthetic 

> are proven for the turbo applications, which is what I wanted to 

> convey. 

> 

> I think Manny's OEM cooler can keep up with 
the RS2 if it is in good 

> condition.  Most I see have coils almost filled with oily dirt on the 

> outside.  Insides can be nasty also, so I would check the present oil 

> cooler out before opting to buy an aftermarket system.  Perhaps 

> he needs a bigger cooler.  I certainly don't want to suggest that 

> Manny needs to "back off" on any of his sessions.  : > ) 

> 

> Tom 

> 

> On Mar 24, 2009, at 6:44 PM, djdawson2 at aol.com wrote: 

> 

>> I think the bearing section of the turbo is, without question, the 

>> place where oil temps are highest... hence the after-cooling pump. 

>> 

>> 

>> -----Original Message----- 

>> From: Brett Dikeman <brett.dikeman at gmail.com> 

>> To: Tom Green <trgreen at comcast.net> 

>> Cc: Manuel Sanchez <manuelsanchez at starpower.net>; Scarlist 

> <s-car-list at audifans.com 

>>> 

>> Sent: Tue, 24 Mar 2009 2:29 pm 

>> Subject: Re: [s-cars] Oil Temperature 

>> 

>> On Tue, Mar 24, 2009 at 3:36 PM, Tom Green <trgreen at comcast.net> 

>> wrote: 

>> 

>> 

>> 

>>> At the turbo, the oil probably reaches the flash point, so that 

>> can't be good. 

>> 

>> 

>> 

>> I'm not sure what the relevance of flash points are, but the flash 

>> 

>> point of 15w50 Mobil1 is 235C; 455F.  The coke point of most 

>> 

>> synthetics is even higher.  In a water-cooled-center-
section k24, you 

>> 

>> think the oil is heated by a differential of more than 100C from the 

>> 

>> coolant?  These cars were designed to work just fine on dino oil... 

>> 

>> 

>> 

>> One would think oil sees the hottest surfaces around the 

>> 

>> pistons/rings/cylinder wall. 

>> 

>> 

>> 

>> Brett 

>