i dont agree.If serviced and inspected periodically there is no problem.Even at monster powered road/circuit time attack carsQuote:
Originally Posted by Mirek
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i dont agree.If serviced and inspected periodically there is no problem.Even at monster powered road/circuit time attack carsQuote:
Originally Posted by Mirek
I don't agree either. You can have a look in rally results from anywhere in the world. Fact is that gr.N cars are less reliable than purpose-built 4WD cars especially in long and rought events. The most common mechanical problems are definitely those of drivetrain - I would say mostly gearboxes and driveshafts and most of these problems happen on first gear which means it's related to the torque extremum.
i didnt said that N cars are more reliable than purposed build cars.I said about Nikaras evo 9 rear differential.Quote:
Originally Posted by Mirek
And if they are well serviced and inspected there is no problem.
For safety reasons, everywhere I went they change the gearbox at the overnight service on Gr.N cars, some wealthier teams even the rear diff. Many times (i.e. especially on evets with a lot of hairpins) even with these precautions the cars are breaking their transmissions a lot of times. But obviously, good maintenance helps this matter, but that's just a part of the deal IMO.Quote:
Originally Posted by dimviii
At Acropolis rally they didnt changed diffs and gearboxes every day,even the top teams with winning cars.Maybe 1 time.But that was same for wrc cars also.Quote:
Originally Posted by TWRC
To say that they are unreliable after some 20+ years winning championships worldwide at national and world championships is not true.
About the rallies with hairpins i dont agree.If it is inspected,well maintened with right fluids inside,and right preload there is no way to broke after 150-200 stage km.Yes the stress is bigger,specially at asphalt,but a well fixed diff will not have a problem.
Gear boxes are not oem parts but Quaife,Drenth Samsonas etc A fresh serviced one have not problem for 3 days rally at wrc level.
Because is not a sequential,big role plays the guy who uses it for right use.
Two things as Dimviii says:
1) user
2) maintenance
But like to add that a snow rallysurface for me looks more nice to the car than hairpins/tarmacrallies.
Dimitris, as TWRC wrote teams here in CZ also often change differentials in overnight service. Even with the best cars such as Pech's Evo they did so. Many also do other pre-caucious measures such as careful starts into the stage without locked central diff.
The example with Acropolis. You write maybe once. But they can't change them more times as FIA rules don't allow You to have more than one spare (if I'm not mistaken).
so you say that a diff at an evo N car will not cope a regional rally thats why they will change it?
Yes at Acropolis with these restrictions they dont have problem to finish and win rallies.Much more kms than 1 day at regional rallies, much more heat,and much more preload for gravel use.
No, I mean that there have been issues with drivetrain reliability with some 600 Nm of FIA engine hence the frequent pre-caucious changes of the diffs and that the logic tells me that with even higher torque the reliability must be worse. To which extend I can't tell but it can hardly stay same.
Video of Veiby from Tahko Rally: https://www.youtube.com/watch?v=j7XP06DpJok
By the way are those really Lancers WRC Step.1 used in FRC?