2019-20 ACO/2020 IMSA GTE/GTLM regs changes?

[chernaudi]

I've been reading that the 992 Porsche 911 RSR (called 911 RSR-19) and the C8R Corvette are being developed to newer ACO/IMSA GTE/GTLM regs. Are these rules much different than the 2016-present rules, or a tweaked set of regs? And what's supposed to be different?

[MaskedRacer]

Originally Posted by chernaudi

I've been reading that the 992 Porsche 911 RSR (called 911 RSR-19) and the C8R Corvette are being developed to newer ACO/IMSA GTE/GTLM regs. Are these rules much different than the 2016-present rules, or a tweaked set of regs? And what's supposed to be different?

Don't think GTE regs have changed since 2016. Otherwise you'd see Ferrari come out with a new car by now. The C8 is Corvette's first crack at it since 2016. Porsche is well Porsche, they update and come out with new models all the time. More frequently than anybody else.

[Mike E]

The 2016 regs are still current, with some minor amendments, as published on Thursday 04 July.

Article 11: Eligibility
"In the group LMGTE AM only cars having 1 season old or fully in compliance with the specifications of the previous season car will be admitted."
'Season' replaces 'year' because of the Superseason overlap.

Article 333: Lubrication
Oil radiators redefined as heat exchangers.

Article 401: Fuel tank
"Location - Original location may include alternative energy storage volumes integrated in the road car primary structure and provided that the road car structure remains unmodified and the volumes are external to the driver compartment (Hybrid battery location). "
In other words, if the road car has a hybrid system, the location of the battery can be considered as part of the original fuel tank location.

Article 404: Fuel flow metering (new rule)
A homologated "Fuel Flow Meter" (Technical List n°45) must be integrated into the fuel system according to the specification included in Appendix and the supplier instructions.

Article 503: Lighting system
An optional additional auxiliary lighting equipment may be homologated providing that the bodywork shape remains identical.

Article 605: Diff and final drive
Limited slip diff: Preload adjustment must be passive and only possible with the use of tools.
Oil cooling: Oil radiators redefined as heat exchangers.

Article 701: Axle parts
Subframes: The steering rack, the engine supports and the gearbox supports may be mounted on the subframe.
Ballast may be mounted on the subframe.

Article 804: Steering
Power steering: Cooling of the power steering fluid is authorized.

Article 901-1: Interior
Additional equipment permitted inside the cockpit: electronic equipment was previously to be contained in boxes with screwed covers removable with tools. This requirement has been removed.
Interior equipment must be able to withstand a deceleration of 25g without
detaching.

Article 902: Exterior
Glazing: The rear window may be replaced by a non-transparent material provided that it fulfils any other requirements stated in the present regulations (i.e. fire resistance, leak-proof, etc…).

Article 1002: Safety seat and safety harness
Something about seat mountings...

[hondafan37]

Fehan pushing for GT Convergence.

https://sportscar365.com/lemans/wec/...t-convergence/

[chernaudi]

I do agree that at least the cars should be convertible from one spec to another. However, we know why we have things like the mid-engine 911 RSR and such. It was due to ACO rules changes allowing for stuff like big volume front and rear diffusers similar to what GT3 cars were starting to run. This was mostly so the ACO can claim to have the fastest production based GT cars in the world currently.

What I don't understand is why didn't the ACO, if they were so concerned about speed gaps to GT3 cars, give GTE/GTLM cars stuff like front fender louvers and some more freedom regarding air extractors with the front and rear fenders. And also, since GT3 cars can be BOP'd up to 550bhp, why not give GTEs a similar power bump? I'd even go as far as letting GTEs run carbon brakes, since in the long run the cost difference between carbon and metal rotors probably isn't much different.

[MaskedRacer]

So could the Porsche 911 RSR and Corvette C8R be considered "convergence killers"?

[broadrun96]

Originally Posted by MaskedRacer

So could the Porsche 911 RSR and Corvette C8R be considered "convergence killers"?

I think less so than others, both of those teams would build new cars if needed for new convergence rules in 2 seasons. And think Fehan would in a second to try a build up the business with Vette GT3s, but would GM let them is the age old question.

[chernaudi]

I wouldn't consider them convergence killers. Especially the Porsche, given that the 992 RSR will probably be out by 2022.