Torque output was one of the motivations for Porsche to make the unprecedented move to a 4.2L block in the RSR; the short dump side exhausts were apparently also torque-motivated.

In an early interview during the race, Estre said that #92 suffered from poor acceleration off the corners; the way he conveyed the info led me to believe that the Porsche was deficient in race trim vs what the team expected, not that it was an inherent competitive disadvantage vs. the remainder of the class due to BOP.

 

While turbo may be easier to keep in optimal rev range.. in racing series like these isn't BOP by far greatest factor? You can make any car competitive with any other car almost right?

 

Yup. All the turbo vs non-turbo arguments might have merit if there weren't BOP.

RSR won Spa WEC race, with the drivers complaining about having to conserve fuel through the race, i.e., they couldn't run flat out due to BOP fuel restrictions.

As for Le Mans BoP:

"However, the Aston has been given a slight increase in turbo boost across all RPM levels compared to its configuration in the 2019 race, along with a 1-liter increase in fuel capacity.

Porsche’s 911 RSR-19, which will be making its Le Mans debut, has been given a minimum weight of 1286 kg with a 30.0 mm air restrictor.

It is a 20 kg increase and 0.3 mm reduction in power compared to the previous-gen Porsche that competed at Le Mans last year but is similar in weight and comparative power output in the 2019-20 FIA World Endurance Championship races, which utilizes an automated BoP system."
https://sportscar365.com/lemans/wec/...g-regulations/

The outcome should hardly have come as a surprise to anyone....

 

This article contains quotes from several Porsche drivers and engineers; there may be duplicates with the OP.

https://www.motorsport.com/lemans/ne...paign=widget-1

None of them reference BOP, which makes me believe that the unexpected lack of straightline pace is attributable to something else in the team’s view.

For an example of BOP, the Porsches weight 100 kg more than the BMWs in IMSA GTLM. 100 kg is substantial, of course.

 

On the issue of the 4.0 liter engine, RSR vs. 991.2 GT3: this is from September 2017 Excellence magazine:
"For the 991.2 GT3 we adopted the 9A1 4.0 liter motor from the 911 RSR race car, which has been proven to be strong and reliable in competition"
"If it does not break during a 24-hour endurance race, it will not break in normal road use"
Modified for road use into what the engineers call 'the 9A1.5 Spec' - steel crankshaft, lower friction, 13.3:1 compression ratio, Titanium connecting rods and forged lightweight pistons. Crankshaft has larger bearings.

It's a hell of an engine. I'm excited for the 992 GT3, definitely.

 

I never said it wasn’t an impressive engine. You, however, characterized it as “nearly identically save a few changes for road use.” I wouldn’t be proud of broadcasting that degree of credulity.

 

Agree with all of these things. However, to my knowledge, you could build an RSR engine out of a GT3 street engine - it's not what Corvette were doing in years past, running a different block alltogether.

RE: BOP, Porsche got hosed. The car has been fast at all rounds up to this point. However, both the European and American teams have lost points due to many un-Porsche like things (small reliability issues, absent-minded driving, and bad luck). The RSRs have consistently been towards the front this year, but haven't been able to capitalize. We know straightline speed is not its forte, something that we've seen at Daytona and now Le Mans. Le Mans was going to be tough if they were looking to penalize Porsche because of their speed AND it happened to coincide with a circuit not suited to the car.

RE: going turbo - bad idea assuming a consistently fair BOP. More weight, more complexity, worse weight distribution balance, and fuel economy would be ??? This sort of runaway in terms of BOP is not supposed to happen. The regulators screwed up and took Porsche out of the game, while the other manufacturers sandbagged in qualifying. I'm not sure how Porsche determine optimum engine size, but Manthey was running a 4.4 liter Mezger engine in endurance racing years ago. I'm not sure why the guys stopped at 4.2 in this engine. They need the flattest possible torque curve to keep touch with the turbo cars.

RE: the side dump exhaust, I was always under the impression that the shorter the pipe off the header, the more "open" the flow and therefore the more tailored it is to high horsepower. I thought the two-into-one systems that exit in the rear created better backpressure and thus more torque. Happy to be corrected, but could this be the reason that we're seeing Porsche testing a center-pipe exhaust a Monza earlier?

 

I had thought the same, but one of the drivers told me last fall (when the car was still testing) that the new car “sounded like ****” but that the side exit exhausts were primarily for torque. I seem to recall an article mentioning the same thing, but I can’t find it.

The “new” center exit exhaust is apparently for customers who will be running the side exit RSRs privately once they move into vintage racing - it’s quieter than the side exit setup, which is unmuffled.

 

No Mid Ohio for Porsche factory team

https://sportscar365.com/imsa/iwsc/p...from-mid-ohio/

 

Ohhh...we lost...now we'll pout until we get a BOP adjustment in our favor. Sad...

 

The Wuhan Flu is messing up a lot of racing. My CT-based shop won't provide support or transport for this weekend's International GT race at VIR due to Covid restrictions. It's all bit mind-numbing; fine to race in WV at Summit Point but no go for next door at VIR. I'll be happy when all this is in the rearview mirror.

Now about that Charlotte Motor Speedway comment??

 

I had not heard anything regarding the comment you’re referencing:

Quote:

Despite rumors of the program being terminated altogether, five races early from its planned end, Sportscar365 understands the team plans to be back in action next month at Charlotte Motor Speedway.

I have been to nearly every major IMSA race held in the past 5 years, and I have a very good relationship with the head of Porsche’s VIP hospitality offerings in North America. Porsche is planning to have a small setup at Petit Le Mans, a setup at Sebring, and nothing for Daytona in January per a conversation that I had with him this week. I also know one of the Germans who works on motorsport business development for Formula E and WEC (he also used to work in the LMP1 program). I have reached out to him to see how he’s enjoying his post-Le Mans quarantine, but haven’t heard anything yet.

I plan on being at Petit Le Mans next month, but I’m hardly interested in paying ~$2K to go to Sebring (tickets, flights, lodging, rental cars) for an experience that won’t feature WEC, will have outside hospitality on the Fangio terrace (it is very, very loud given all the concrete), and will require masks at all times apart from when eating and drinking.

 

From the referenced article:

"Bamber, meanwhile, has been reassigned to a KCMG Porsche for the Nürburgring 24 this weekend, as one of several replacement drivers to support Porsche’s effort in the race.

Despite rumors of the program being terminated altogether, five races early from its planned end, Sportscar365 understands the team plans to be back in action next month at Charlotte Motor Speedway."

 

Oh, my comment was about them dropping the rest of the season - which is “unfounded” based on someone I know on the team. The Charlotte Roval event is a GT-only replacement for Lime Rock; they announced it awhile back.

 

Yawn. Give me the component differences then.