Rev Range data not possible on tip

[DeeKay17]

Asked a well-known used car dealer (who deal exclusively in prestige cars based just outside London) for some DME data of a 997.1 Tip I was looking to purchase from them.

I was told categorically that rev range information is not possible from a Tiptronic, only the manuals have this data on the DME. Surely this isn't correct?

Dealer also reluctant to give me the DME mileage to compare to the dash.

Alarm bells ringing anyone?

[mollytherocker]

Why do you need the rev range data? You cant over rev an automatic.

[Far Cough]

I seem to remember reading that some auto ( pdk ) cars have shown over revs ! although I do admit it does seem counter intuitive

[sportsandclassic]

Hello,

The engine control module is the same for manual and automatic cars so the rev range data is available on both variants.

As for automatic transmission over rev it is possible if the car leave the ground like over a hump back bridge and it will start logging data into the rev ranges as the car is fully loaded and then it looses all traction with the road so over revs past the electronic limiter. Seen this happen before but as a rule there are far less over revs present in automatic cars.

Mike

[Tom 911V]

Mike is absolutely correct, I've seen this too.

Tom 911Virgin

[mollytherocker]

Well, I stand corrected. Im surprised that the limiter doesnt stop the overrev, but you guys know much more than I do!

[supermono]

But hang on, the engine alone provides acceleration to itself once the ignition is cut there is no more acceleration no matter how quickly it was accelerating before the cut.

Acceleration doesn't have inertia.

It's like saying if you throw a ball really really really hard it can carry on accelerating just after it leaves the hand.

I'm sure overrevs get logged because I'm sure the ECU is buggy from direct experience. I don't buy this overrevving by fast acceleration / missed gear / taking off story

However I do believe the dealer is lying about the data availability.

SM

[porkyspecialist]

SM has a point, I would love to know why the hard limiter would not work regardless of whether the wheels were on the ground or not. I half understand the downhill fast/spin backward argument, but I really can't see a real world situation that this would happen on so many tips, so to me the DME must have an inherent fault with the logging & is bugging out.

Just my 2p.

[BertBert]

supermono said:

But hang on, the engine alone provides acceleration to itself once the ignition is cut...

that would be making the assumption that an ignition cut is absolute and happens when you think it does. Physics isn't necc that accommodating. TO the OP, I'd walk. The dealer is telling you porkies which means that they are at least muppets. Probably muppets with something to hide.
Bert

[DeeKay17]

Just by way of update, despite telling the dealership that Porsche confirm rev range data is available on the tip and a promise by them to provide if it is indeed possible, no info provided.

Clearly they don't want to sell to me or have something to hide on that car!

[Rockster]

DeeKay17 said:

Just by way of update, despite telling the dealership that Porsche confirm rev range data is available on the tip and a promise by them to provide if it is indeed possible, no info provided.

Clearly they don't want to sell to me or have something to hide on that car!

My WAG is the odometer has been tampered with and the DME over rev range counters and the run times and total engine run time would make this obvious.

Walk away. Remember there is always another car.

BTW, a Tip can have over revs. My tech friends tell me if the car is driven down a hill, a steep hill, the engine can be over rev'd even though the rev limiter will cut fuel to the engine.

[mollytherocker]

Rockster said:

My WAG is the odometer has been tampered with and the DME over rev range counters and the run times and total engine run time would make this obvious.

Walk away. Remember there is always another car.

BTW, a Tip can have over revs. My tech friends tell me if the car is driven down a hill, a steep hill, the engine can be over rev'd even though the rev limiter will cut fuel to the engine.

I can see how that would be possible but who in the hell would let it do that?

[EuroSag]

As said above, I think this is more a question of run time vs odometer reading, rather than anything to do with over-revs.

Might be worth trying to contact a previous owner to tally up the miles, or better, just walk away. There's plenty of cars out there.

[Rockster]

mollytherocker said:

I can see how that would be possible but who in the hell would let it do that?

The same type of person who'd miss a shift from 3rd to 4th and instead grab 2nd in a manual equipped car?

[Guyr]

Rockster said:

The same type of person who'd miss a shift from 3rd to 4th and instead grab 2nd in a manual equipped car?

Maybe, but there's a big difference between finding an unlikely and rare slight technical over-rev in a tip/pdk car which probably went about 100 revs over the limit at max verses a manual 'oops wrong gear scenario' where the engine went to 10,000rpm.

I would check for over-revs on a manual car, but personally wouldn't bother on a pdk/auto.

[Rockster]

Guyr said:

Maybe, but there's a big difference between finding an unlikely and rare slight technical over-rev in a tip/pdk car which probably went about 100 revs over the limit at max verses a manual 'oops wrong gear scenario' where the engine went to 10,000rpm.

I would check for over-revs on a manual car, but personally wouldn't bother on a pdk/auto.

Well, I would check for over revs in a Tip. While someone blasting down the Matterhorn and zinging the thing to 10K is not likely one gets confirmation there's nothing scary. Besides the reading gives one the total engine run time and that is used to sanity check the odometer.

Also, the engine might have been "tuned" and the rev limit raised.

[IanHug]

Rockster said:

Also, the engine might have been "tuned" and the rev limit raised.

Good point I think some of the chipping that goes on does raise the rev limits.

[alexisn]

My DME shows 4 ign 'sparks' in the over rev range, it's a tiptronic, not significant I feel. The most significant concern is the bore condition, I would never but a 996/997 until a bore inspection was carried out, it would take a massive over rev to damage or throw the rods on a Porsche. The mileage reading can be compared to the total distance travelled as recorded by the DME, but bear in mind that the DME records in Kms.