Rev 1 & rev 2 query on 996 GT3

[gttastic]

I have 2 print-outs from 2 OPCs that I requested just before I bought the car(1) and during a routine service(2)

(1) OPC Silverstone: 13,000 miles - number of ignitions, range 1 = 2966 343.0h
number of ignitions, range 2 = --
operating hours counter = 346.2

(2) OPC Leeds: 20,000 miles - number of ignitions, range 1 = 2966 343.0h
number of ignitions, range 2 = --
operating hours counter = 628.6

Can anybody tell me what the figures mean?

Thanks in advance.

[thegoose]

Range 1 is redlining it to the point the rev limiter cuts in, range 2 can only be achieved as a mechanical over-rev (i.e. changing down too early and making the car/wheels/transmission turn the engine faster than the rev limiter allows).

It would seem your read out is good, with no range 2's whatsoever and not having been on the rev limiter since you bought it.

Good to see the OPC providing this info without being asked too

[Tino]

But wow! a rev 1 every 4 miles before you bought it!
ETA i'm probably reading it very wrong

Edited by Tino on Wednesday 22 April 09:49

[GT03ROB]

Tino said:

But wow! a rev 1 every 4 miles before you bought it!
ETA i'm probably reading it very wrong

Edited by Tino on Wednesday 22 April 09:49

Think you read it wrong:

2966 ignitions / 6 cylinders = 494 revs
494 rev / 8500rpm = 3.5 secs against the rev limiter

not much really, maybe 5-6 times it's been red lined.

[Murcielago_Boy]

What's the problem with it hitting the rev-limiter?

[Rude-boy]

Murcielago_Boy said:

What's the problem with it hitting the rev-limiter?

Nothing at all if you hit the limiter and then change. that's what it is there to save you from.

It's when you breach the rev limiter (ie a full bore 3rd to 2nd when you meant to go to 4th) that you can cause damage. Commonly known as a mechanical over rev iirc.

[gttastic]

GT03ROB said:

Tino said:

But wow! a rev 1 every 4 miles before you bought it!
ETA i'm probably reading it very wrong

Edited by Tino on Wednesday 22 April 09:49

Think you read it wrong:

2966 ignitions / 6 cylinders = 494 revs
494 rev / 8500rpm = 3.5 secs against the rev limiter

not much really, maybe 5-6 times it's been red lined.

GT03ROB,

Would the number of ignitions always be divisible by 6?

How does 494 revs @ 8500RPM equate to 3.5 seconds?

How does 3.5 seconds against the rev limiter equate to 5 or 6 red line attempts?

[spikeyhead]

There are only three ignitions per revolution on a six cylinder four stroke engine.

[Rude-boy]

gttastic said:

GT03ROB said:

Tino said:

But wow! a rev 1 every 4 miles before you bought it!
ETA i'm probably reading it very wrong

Edited by Tino on Wednesday 22 April 09:49

Think you read it wrong:

2966 ignitions / 6 cylinders = 494 revs
494 rev / 8500rpm = 3.5 secs against the rev limiter

not much really, maybe 5-6 times it's been red lined.

GT03ROB,

Would the number of ignitions always be divisible by 6?

How does 494 revs @ 8500RPM equate to 3.5 seconds?

How does 3.5 seconds against the rev limiter equate to 5 or 6 red line attempts?

I'm sure he will come back to you but iirc.

Think about taking it to the red line and then changing, how quick on the draw are you? This is a GT3 so the chances are it as seen a track or two, and therefore had a fair few full bore changes. I would guess you would be no more than a tenth or 2 on the limiter, perhaps less. Then again you could be shooting past a line of traffic in 3rd and miss the change to 4th as you are looking to pull back in, etc and be on the limiter for half a second.

I would guess yours has been to the limiter between 10-30 times.

Edited by Rude-boy on Wednesday 22 April 11:06

[GT03ROB]

gttastic said:

GT03ROB said:

Tino said:

But wow! a rev 1 every 4 miles before you bought it!
ETA i'm probably reading it very wrong

Edited by Tino on Wednesday 22 April 09:49

Think you read it wrong:

2966 ignitions / 6 cylinders = 494 revs
494 rev / 8500rpm = 3.5 secs against the rev limiter

not much really, maybe 5-6 times it's been red lined.

GT03ROB,

Would the number of ignitions always be divisible by 6?

How does 494 revs @ 8500RPM equate to 3.5 seconds?

How does 3.5 seconds against the rev limiter equate to 5 or 6 red line attempts?

Ok as pointed out by others, I'm a dumb st , so lets say it's divided by 3 so 1000 revs

1000/8500 = .1176 x 60secs = 7secs

I'd guess you'll hit against the limiter for around half a second, maybe less thats still only around 15-25 times. Anyone thats driven a GT3 knows it ain't difficult to bounce off the limiter especially in 2nd gear. I really wouldn't be worried about it.

[robmug]

gttastic said:

I have 2 print-outs from 2 OPCs that I requested just before I bought the car(1) and during a routine service(2)

(1) OPC Silverstone: 13,000 miles - number of ignitions, range 1 = 2966 343.0h
number of ignitions, range 2 = --
operating hours counter = 346.2

(2) OPC Leeds: 20,000 miles - number of ignitions, range 1 = 2966 343.0h
number of ignitions, range 2 = --
operating hours counter = 628.6

Can anybody tell me what the figures mean?

Thanks in advance.

The 343.0h figure is that last time a stage 1 overrev was recorded. operating hours counter is the total number of operating hours. So, the car hadn't hit the limiter (stage 1) between 343 hours and 628.6 hours.

It also tells you that the average speed of the car at 20,000 miles was 31.8 mph (20,000/628.6)

As stated above, the key figure is the stage 2, as that is the mechanical over-rev on a downshift.

[Rude-boy]

robmug said:

It also tells you that the average speed of the car at 20,000 miles was 31.8 mph (20,000/628.6)

Poor show for a GT3

[Hereward]

Rude-boy said:

It's when you breach the rev limiter ... that you can cause damage. Commonly known as a mechanical over rev iirc.

I've done that in a Dodge Viper at the end of Revett Straight at Snetterton, changed down too early.

[asbo]

Very interesting reading.

I dread to think what the figures on mine would look like...

[lightweight]

At the risk of devaluing my car(not that it will be for sale in the UK) it had a rev range 2 at 16 hours. James at Parr was amazed at this , and just how much power that it puts out at 50,000 miles! go figure.

Rev range 2 is not always terminal!

Edited by lightweight on Wednesday 22 April 14:32

[gttastic]

Thanks for the info so far guys, but does anybody specifically know what the various figures relate to? I'm not worried, just curious.

[GT03ROB]

gttastic said:

Thanks for the info so far guys, but does anybody specifically know what the various figures relate to? I'm not worried, just curious.

NOt quite sure I understand the question, but I'll try to explain.

Rev range Type 1 is when you hit the rev limiter. Type 2 is when the engine revs above the limiter, becasue the limiter will not work if you drop into too lower gear, as the engine is being revved mechanically by drive from the wheels.

All the number of ignitions is is the number of times the cylinders have fired against each case above.

[gttastic]

GT03ROB said:

gttastic said:

Thanks for the info so far guys, but does anybody specifically know what the various figures relate to? I'm not worried, just curious.

NOt quite sure I understand the question, but I'll try to explain.

Rev range Type 1 is when you hit the rev limiter. Type 2 is when the engine revs above the limiter, becasue the limiter will not work if you drop into too lower gear, as the engine is being revved mechanically by drive from the wheels.

All the number of ignitions is is the number of times the cylinders have fired against each case above.

I understand the rev range 1 & 2 differences bit but how many times has the engine hit the red line limiter (on the way up)? 2966 times, 988 times, 494 times, another figure?

343.0h - I take it this was the last time that it was red lined? And has not been red lined since?

[GT03ROB]

gttastic said:

GT03ROB said:

gttastic said:

Thanks for the info so far guys, but does anybody specifically know what the various figures relate to? I'm not worried, just curious.

NOt quite sure I understand the question, but I'll try to explain.

Rev range Type 1 is when you hit the rev limiter. Type 2 is when the engine revs above the limiter, becasue the limiter will not work if you drop into too lower gear, as the engine is being revved mechanically by drive from the wheels.

All the number of ignitions is is the number of times the cylinders have fired against each case above.

I understand the rev range 1 & 2 differences bit but how many times has the engine hit the red line limiter (on the way up)? 2966 times, 988 times, 494 times, another figure?

343.0h - I take it this was the last time that it was red lined? And has not been red lined since?

Correct re the 343hrs, you won;t know how many times it's been red lined, it can't be calculated precisely from the data. The estimates we've given of being in the range 15 - 30 is as good as you can get from that data. It's not hundreds, it's very unlikely to have been single figures.

[BLKROKT]

Type 2's are not only mechanical. If you have a remap that increases the limit, Type 2's will register every time you go over the factory-set point. I never even once mis-shifted my car down and ended up registering thousands of Type 2's. Just something to keep in mind.