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Porsche Motorsport Division X51 PowerKit (320 PS/235KW)

That's a good point!

Who was right then?

Loser will need to push twenty in the stream at the bottom of the garden and say six Hail Marys!
 
Apparently we'll have to wait for the book and buy the answer.

Certainly I have read as much as I can find in Porsche books, Porsche forums and google in general.

One thing for sure is I wasn't there, so I only have what I read to go on, and until I find another source, that won't change.

There really isn't a great deal written about the original X51.

Even Porsche were tight-lipped about it in the brochures and price lists of the time, I know as I have now collected 1998 to 2005 996 brochures in electronic or hard-back variety.

Perhaps I should approach PCGB (the club and the car importer) and see what info or leverage they have on the factory.

I know I asked for the 996 X51 production numbers and the factory said they didn't even keep a tally of that during the production run. :dont know:
 
Yeah but no but..

What if you're wrong? You'd have to pay the penalty.

I would leave it if I were you mate, this bloke sounds like he knows what he's talking about... :roll:
 
Thanks, my next job then.

In fact, I think I have found where I am spending this August:
photo.JPG


:puh:
 
More piccies:

Crated X51 (fitted after nonX51 died):

LostatSea028.jpg



X51 modified oil pan partition box (larger alloy baffles with aperture valving) vs standard small plastic baffled box - AKA "High G sump":

DSC_2018flj.jpg
 
GT4 - what are the similarities & differences between your X51 and the 3.6 X51? How is your power delivered - the 3.6 power hike seems to exist only in the top 1.750rpm, not too useful unless you are in to well illegal speeds, also some gear shifts (at red line) result in falling below this power band...
Is the 3.6 X51 engine also a whisker less unreliable than the standard?
 
Is it worth fitting any individual parts in isolation or do you need the full blown package?

For example is there a benefit to the modified oil pan on a standard 996?
 
OMG it's another Anoraknophobia Nervosa Outbreak(ANO) being the Porsche X51 Mutant Strain on 911uk.com :lol:
 
doulas bader said:
GT4 - what are the similarities & differences between your X51 and the 3.6 X51? How is your power delivered - the 3.6 power hike seems to exist only in the top 1.750rpm, not too useful unless you are in to well illegal speeds, also some gear shifts (at red line) result in falling below this power band...
Is the 3.6 X51 engine also a whisker less unreliable than the standard?

The kit is effectively identical (except where outlined: eg 3.6 pistons are NOT changed, and Turbo/widebody nosed vehicles do NOT get the centre rad).

The underlying engines differ as per standard 3.4 to 3.6: VarioCam Plus, longer stroke, different cooling chambers, updated IMS, modified DME etc.

None of these directly affects the X51 substitutions.

I found the mid-range response better too.

The 3.4 X51 produces its peak power LOWER down the rev range than a non-X51.

The 3.4 X51 develops more torque than the non-X51.

Whereas the 3.6 X51 produces its peak power at the same rpm as a non-X51.

The 3.6 X51 develops NO more torque than the non-X51, additionally, what torque it has is developed later.

The comparative performance specifications are:

3.4
Power: 300 PS @ 6,800 rpm
Torque: 258 lbft @ 4,600 rpm
Idle speed: 700 rpm
Rev limit: 7,300 rpm
Top Speed: 174 mph (280 kph)
Acceleration: 4.8s 0-60 mph (5.2s 0-100 kph)
3.4 X51
Power: 320 PS @ 6,600 rpm (corresponding to 252 lbft)
Torque: 266 lbft @ 4,750-5,500 rpm
Idle speed: 800 rpm
Rev limit: 7,400 rpm
Top Speed: 179 mph (287 kph)
Acceleration: 4.6s 0-60 mph (5.0s 0-100 kph)


3.6
Power: 320 PS @ 6,800 rpm
Torque: 274 lb ft @ 4,600 rpm
Idle speed: 670 rpm
Rev limit: 7,300 rpm
Top Speed: 178 mph (285 kph)
Acceleration: 4.6s 0-60 mph (5.0s 0-100 kph)
3.6 X51
Power: 345 PS @ 6,800 rpm (corresponding to 268 lbft)
Torque: 274 lbft @ 5,000 - 6,000 rpm
Idle speed: 670 rpm
Rev limit: 7,300 rpm
Top Speed: 181 mph (290 kph)
Acceleration: 4.5s 0-60 mph (4.9s 0-100 kph)


Porsche 996 3.4 Tequipment Brochure said:
[about the 3.4 X51]
A characteristic of the new engine is its continous power development, particularly at higher engine speeds above 5,000 rpm.

Porsche 996 3.6 Carrera Brochure said:
[about the 3.6 X51]
The X51 results in greater outright power at higher engine speeds as well as a more dynamic, free-revving response.

The sound of the car is also enhanced, particluarly in conjunction with the optional sports exhaust system.
 

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baptistsan said:
Is it worth fitting any individual parts in isolation or do you need the full blown package?

For example is there a benefit to the modified oil pan on a standard 996?

It is a very popular mod in the US to fit the additional third radiator for racing/tracking (to both Boxsters and 996).

Additionally, often the High-G sump is fitted too (again for racing/tracking purposes).
 
the strain you refer to, Wizard, has been rendered extinct by critical-mass innoculation. The new strain is currently endemic but once the secrets of the X51 become commonly known to a certain number a mass epidemic of pandemic proportions will occur. See the values of the X51 versions of the 996 rise through the stratosphere as punters learn that this mod gives a power benefit impossible to gain by remapping/induction kits/other after market tatt!!! Meanwhile the 'cooking' 996? Doomed to greater depreciation I fear, which if I recall will have your ilk opening another bottle of decent Pomerol??
 
doulas bader said:
GT4 - what are the similarities & differences between your X51 and the 3.6 X51? How is your power delivered - the 3.6 power hike seems to exist only in the top 1.750rpm, not too useful unless you are in to well illegal speeds, also some gear shifts (at red line) result in falling below this power band...
Is the 3.6 X51 engine also a whisker less unreliable than the standard?

Sorry, in my explanation above, I may have not been clear. The diffrences in power delivery are down to the underlying engine and its tunable envelope.

Although the mechanical upgrades are basically the same, the DME remap (and indeed base code) will be quite different.

The DME went from 7.2 (or 5.2 if not eGas) to 7.8.

This is a far more capable unit (from an ECU point of view).

Found a scruffy power deliver chart for 3.6 X51 too (with the odd torque displacement to higher revs):
 

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Thanks GT-4 - most illuminating and explains why I couldn't find the centre rad on my Anniversary car (no extra safety margin on cooling for me, then - why did they leave the centre rad out on my car?).
Do you have the 3.6 X51 power curve comparison in a format I can download?

I reckon your 3.4 X51 would be a nicer car to drive than the 3.6X51... I had a 3.4 and it felt a lot more alive and lythe than any 3.6 I have driven (I know, it is very much lighter). Also your power gain must be far more useable. Plus your engine will be more bullet proof if you upgrade your IMS (no 3.6 coolant channel issues/longer bore hot points). The 3.6X51 seems to be more like an after thought and less 'designed' from the ground up like that of the 3.4, hence power stuck on to end of rev range (? more ECU trickery than mechanical improvements, plus the standard 3.6 already has a huge chunk of mid range torque that the 3.4 didn't, making increase more difficult) and a power curve that no longer matches the gear box ratios (ie redline up changes result in dropping out of the power band in the 3.6 X51). Also Porsche have engineered in a huge sound difference at 5,750 rpm which makes the power step 'feel' greater than it actually is (looking at the flat-ish curve showing increase in BHP whilst the tourque declines at revs over 5,500. Woa is me, I have bought a Porsche/DMS tat-mobile!! What are the respective 0-100mph times?
 
any owner who has this option fitted has won a watch but it was an expensive/eye watering option from the factory.

X51 cars are fetching up to £2k more :thumb:
 

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