What's The Diff?

[GTRMagic]

Final drive ratios may change at some circuits to reduce time spent bouncing off the rev limiter.

300km/h plus at Bathurst may be one of the unintended consequences!

Story Here

[peckstar]

will be interesting to see what this means at other parts of the track, a bit slower up the mountain maybe

[chavez]

Either the teams should be free to choose which ratio or if cost is a concern allow the teams to choose from a selection of ratios.

When NASCAR decided to set the ratios for the "rear gear" they at least made a selection of ratios (often only two) available for the team to choose. Not sure if this is still the case.

But bouncing off the rev limiter is really village Grand Prix stuff.

[Umai Naa]

It might invigorate some teams' engine program if anything.

Personally, I think its long overdue.

[Axeman444]

Originally Posted by chavez

...the teams should be free to choose ... from a selection of ratios.

wasn't this how it was several years ago?

[GTRMagic]

There are currently a series of 'drop gear' ratios in the series Operations Manual. There has been a suggestion that the list may be added to, for Bathurst at least.

Wonder how much harder it might be to get them off the line?

[Just Do It!]

Doesn't John Bowe hold the record down Conrod Straight in an OzEmail Falcon at 304 km/h??

[Razor]

The Need for Speed is real.

[F J Nedos]

Raise the rev limit to 8500rpm

[EL GT]

As long as the engine builders are happy my feelings are they let them run another 200rpm or 300 rpm track dependent to stop them hitting the limiter at in top. This is the solution rather than changing overall gearing as this starts another hornets nest. Only top gear can you exceed 7500 max. The other issue if I remember rightly was 300k changes insurance precedents and that's another reason they've kept cars under the 300 mark at Bathurst. This may not be an issue no more, I'm not sure.

[peckstar]

Originally Posted by EL GT

As long as the engine builders are happy my feelings are they let them run another 200rpm or 300 rpm track dependent to stop them hitting the limiter at in top. This is the solution rather than changing overall gearing as this starts another hornets nest. Only top gear can you exceed 7500 max.

I dont think thats as easy as you think. change of ratios simple. extra RPM massive engine changes as engines now need to do extra RPM

[GreenMachine]

Originally Posted by peckstar

I dont think thats as easy as you think. change of ratios simple. extra RPM massive engine changes as engines now need to do extra RPM

An extra 200-300 revs, in top only, at one(?) circuit, requires "massive" engine changes? Well, it certainly needs someone to tell the ECU that in 6th gear, the rev limit is x00 revs higher than in the other gears ...

I doubt it, that is less than 4% increase (ok, I understand M times Vsquared) but still, if these engines can't take an extra few revs occasionally, I would be amazed - disbelieving actually. It may shorten their TBOH when it is used, but I would wonder about even that.

[F J Nedos]

I am pretty sure the engines already rev higher than 7500rpm on downshifts... so let em scream on upshifts!

[GTRMagic]

Originally Posted by F J Nedos

I am pretty sure the engines already rev higher than 7500rpm on downshifts... so let em scream on upshifts!

Until they break valvesprings and everyone is up in arms about reliability...

[EL GT]

Originally Posted by peckstar

I dont think thats as easy as you think. change of ratios simple. extra RPM massive engine changes as engines now need to do extra RPM

Pecker,..use ya head mate as a veteran you should know the implications of changing the final drive ratios. Extra 200 rpm only effects conrod, final drive ratio change effects every sector of the track gear ratios are compromised everywhere and it will create a hornets nest.

[GTRMagic]

Change the ratio for 6th gear?

[FPV8U]

Make 6th too tall without adjusting the other gear sets will see the cars falling to far off the boil on the last upchange and struggle to match current speeds, maybe not an issue for the lead Ford and GM teams but Nissan in particular would get slaughtered on current form in that situation.

[EL GT]

Originally Posted by FPV8U

Make 6th too tall without adjusting the other gear sets will see the cars falling to far off the boil on the last upchange and struggle to match current speeds, maybe not an issue for the lead Ford and GM teams but Nissan in particular would get slaughtered on current form in that situation.

You're onto it mate

[Langers]

Originally Posted by F J Nedos

Raise the rev limit to 8500rpm

What a silly thing to suggest when cost control is so important. The dyno time alone to get the mapping right would not be quick or easy. Changing gear ratio is far more sensible, as long as shift points around the rest of the track are not ruined.

[Umai Naa]

Even if you just changed the final drive ratio, the engine gurus would still need to tweek the ECU mapping to keep the driveability in check.

The OHC engines are having enough issues with this as it is, with their much narrower torque window. Quite often, drivers have remarked on needing a lot more trailing throttle (burning more fuel, whole other problem!), to keep the things on the boil. If they fall off the curve, they're just a dog to get off the corner smartly.