Apex996

Saw this X51 on Ebay, supposedly out of a 40th Anniversary Edition.

http://www.ebay.com/itm/2004-Porsche...-/152124180943

Was interested until I saw it had no scavenge pumps in the heads.
Thought only the X51 add-on kits came without the pumps and that all cars delivered with X51 from the factory would have it. Am I mistaken?

Fracture

answer might be here

http://www.911uk.com/viewtopic.php?t=60293

Schnell Gelb

That is a very interesting link !
As far as the scavenge pump (upgrade) is concerned, JFP recently commented about a [B]North-West Passage[B] in the X51 mods/upgrade. JFP may have the knowledge to clarify the O.P's. question
http://www.911uk.com/viewtopic.php?t=60293
for photos and diagrams:
see post by GT4 on Wed Mar 18, 2015 12:08 pm
and Steve R Sun Apr 05, 2015

Apex996

Great link and one I have not visited in years. Thanks!
The linked "After Sales Training" document suggests that on the 2004 USA 40th Anniv. model did not have the scavenge pumps.

The engine of the special model “40 years 911” is an increased power version based on the 911 Carrera 3.6 liter M96.03.

Engine Modifications:
• Intake air manifold with modified cross section
• Adapted intake runners
• Exhaust manifold with larger cross section and optimized flow characteristics
• Cylinder heads with optimized inlet ports
• Camshafts with greater valve stroke on inlet side and modified inlet/exhaust valve timing
• Inlet valve springs adapted to increased valve stroke
• Modified bulkhead box in oil pan
• Additional radiator
• Modified map for the DME control unit

No mention of the pumps.

jhbrennan

40 AE also does not have "additional radiator" - I'm assuming the reference is to the third radiator that was part of the X51 (non-AE) package. Am curious though if the 40 AE (and C4S) X51 having the turbo front end also have larger capacity turbo radiators??

Ahsai

Yes, my impression is the upgraded scavenge pump only applies to the 3.4 x51.

Slakker

My track car came with a "2nd oil scavenge pump on 4-6 cylinder head (X51 oiling kit)". I haven't taken the time to figure out how it was added. This is on an '06 factory replacement 996.1 3.4L engine.

Apex996

Best part of the UK site thread:

The M96 [996 engine] would support a lateral force of 0.8 g, which meant at least half of the clients using the 996 on the track wouldn't have a problem. But if you used slick tires, the fastest drivers could have oil starvation. We couldn't allow that--it was totally the wrong image of Porsche. So Ampferer designed the GT3 engine for the Cup series.
- Horst Marchart

There you have it. .8g, right from Porsche. Car magazines consistently tested bone stock 996's pulling over .9g in magazine tests. The GT3 pulled over 1g. So Porsche knew they had an engine that was incapable of oiling at the car's physical limits. Sigh.

Apex996

How to add the pump is well documented. I was just under the incorrect assumption that 3.6L 40th Anniv. cars from the factory had it. The pump is still available from Porsche for a minor fee ... $3604 MSRP.

alpine003

I was in the same boat at one point and almost bought an x51 from an engine builder and then realized the pumps were optional add on's which I didn't know at the time. I initially thought all of them came with the pumps as well.

Yeah I thought the same thing when I first read it awhile ago.

Slakker

Ouch!!!!

Slakker

Stupid question but do scavenge pumps and accusumps solve different problems?

alpine003

Basically solves same kind of lubrication problem but different oiling method.

Apex996

Accusump provides oil to entire circuit via solenoid activated switch when pressure drops below preset threshold. (Note, there is a delay between switching threshold and full pressure buildup)

The X51 scavenge pump removes pooled oil from the cylinder head that is trapped during hard cornering.

The baffled sump is supposed to hold oil against the pump pickup.

The best solution so far is a horizontal tray just above the oil pickup that traps a LARGE enough volume of oil below it to feed the pump through even the longest of high G corners.

This type of pan is made by Bodymotion, LNE and Mantis. The Mantis looks to be the best bang for the buck. Just an observation as I have no affiliation.