LMDh (DPi regulations version 2.0)

[canaglia]

Originally Posted by joeb

In an article on Road and Track about the new Caddy engine they had this info on engine regulations that I hadn't seen before:




Any idea how loud the cars are currently? is that 110 decibels similar or a reduction?

hard to say... for what it can help, I had some trackdays experiences and I found out that porsche 911 gt3rs is one of, if not the loudest road car, being in the range of sligtly over 100db... I've seen also some gt3 races and 911 gt3r was quite loud as well... anyway considering that like current dpi, next year lmdh will probably rev between 7000-8000rpm and that will have longer exhausts too, I think they will be quiter than a 911 gt3rs taken as reference. The thing I didn't understand of that sentence is:
will lmdh have 630hp + momentary ERS +40hp boost or will be 670hp all the time with reduced power from ICE when ERS is activated?

[deggis]

Originally Posted by joeb

Any idea how loud the cars are currently? is that 110 decibels similar or a reduction?

Similar if not the exact same wording. It measured at certain distance (15m or so from the edge of the track)

Applies to WEC too.

WEC once apparently accidentally uploaded a document containing noise measurements from a practice session to the Alkamel timing site. All of the LMP2s, Porsches and Fords constantly exceedeed the limit (the same 110) and maxed at about 115 db.

[joeb]

Originally Posted by deggis

Similar if not the exact same wording. It measured at certain distance (15m or so from the edge of the track)

Applies to WEC too.

WEC once apparently accidentally uploaded a document containing noise measurements from a practice session to the Alkamel timing site. All of the LMP2s, Porsches and Fords constantly exceedeed the limit (the same 110) and maxed at about 115 db.

Classic!

[broadrun96]

Originally Posted by joeb

In an article on Road and Track about the new Caddy engine they had this info on engine regulations that I hadn't seen before:

More interesting is the allowance of variance in the ICE/hybrid balance. What's to stop a team from running near zero hybrid and just on the engine? I'm assuming durability but it's 40 hp and the target of 644-697 hp doesn't seem outlandish for teams to get from the engines discussed so far. But just me thinking based on the words of one member of one manufacturer management

[S griffin]

I wonder how many teams will be able to exploit this rule? Seems there are quite a few open areas on the hybrid rules. But there's nothing wrong with that, just gives teams more of a technical challenge. Let's hope the rules work after what has been a tough time for the series

[canaglia]

Originally Posted by S griffin

I wonder how many teams will be able to exploit this rule? Seems there are quite a few open areas on the hybrid rules. But there's nothing wrong with that, just gives teams more of a technical challenge. Let's hope the rules work after what has been a tough time for the series

Honestly it seems like a big grey zone becaus so far I never heard or read anything like that from other lmdh manufacturers statements... honestly I always assumed lmdh were going to be 630hp all the time + 40hp during ERS boost and not variable power from ICE as hybrid LMH cars use to work.
Also because since cadillac is going to use same 5.5L or however another NA LT derivated motor, how can a NA engine may do something like that? With turbo engine is easily achievable just lowering turbo pressure for that range of seconds, but for NA would be quite more complicated unless to use a specific revlimiter maybe ?

[carbsmith]

Both hypercar classes are on a defined power curve at all times through torque sensors, with drive by wire the quick and dirty way is to just reduce throttle opening when the ERS is active.

[PhilipR]

What are the chances we end up with similar outcome as in 2017?
The Cadillac was so much more earlier in development that it was class of the field for most of 2017 even with BOP. Could we have similar situation with the Porsche being clearly ahead for 2023?

No complaints if this happens, just a curiosity

[hondafan37]

Originally Posted by PhilipR

What are the chances we end up with similar outcome as in 2017?
The Cadillac was so much more earlier in development that it was class of the field for most of 2017 even with BOP. Could we have similar situation with the Porsche being clearly ahead for 2023?

No complaints if this happens, just a curiosity

I have the feeling that both the Cadillac and the Acura will be an evolution of the current DPI, even the Acura image looks similar to the current one.

[PhilipR]

Originally Posted by hondafan37

I have the feeling that both the Cadillac and the Acura will be an evolution of the current DPI, even the Acura image looks similar to the current one.

But still heavier car - hybrid system integration might cause some headache that Porsche might be more advanced into solving them.

Are they both carrying same engine forward? Somehow I remember Cadillac saying they will have a new one but I might be wrong

[joeb]

If anything Porsche will have the upper hand because they have been on track testing much earlier than any of the other LMDh cars.

Caddy is utilizing a new 5.5 litre engine in their car and a new chassis for all, so we are just going to have to wait a few more months until the mandatory IMSA tests for all manufacturers this fall.

[seanyb505]

I thought tests were starting in July? Maybe somewhere stupid hot and humid

[broadrun96]

Originally Posted by seanyb505

I thought tests were starting in July? Maybe somewhere stupid hot and humid

Think they are required to be a Road Atlanta after Petit to start the IMSA testing together fun. I think they are all targeting a summer test plan on their own

[joeb]

Originally Posted by seanyb505

I thought tests were starting in July? Maybe somewhere stupid hot and humid

Originally Posted by broadrun96

Think they are required to be a Road Atlanta after Petit to start the IMSA testing together fun. I think they are all targeting a summer test plan on their own

Yes and a December test at Daytona is also mandatory:

https://sportscar365.com/imsa/iwsc/i...ting-timeline/

[seanyb505]

At least two tests have been scrapped. Somewhere in the buckeye state and one in the steel capital.

Last I knew lmdh was destined for the bumps (have to respect them) next month. Unfortunately life takes a new turn. Who knows where any lmdh will hit US soil first. I won't.

[Coach Ep]

Originally Posted by joeb

Yes and a December test at Daytona is also mandatory:

https://sportscar365.com/imsa/iwsc/i...ting-timeline/

Joe, I don't believe the post Petit test is mandatory as not all manufacturers might be ready to run their new car

“Will everybody be ready in October and go to [Road] Atlanta? They may be, but the reality is maybe we won’t because we’re also trying to schedule the appropriate homologation timeline of each individual manufacturer.”

The Daytona one early December most definitely is mandatory.

Originally Posted by seanyb505

At least two tests have been scrapped. Somewhere in the buckeye state and one in the steel capital.

Last I knew lmdh was destined for the bumps (have to respect them) next month. Unfortunately life takes a new turn. Who knows where any lmdh will hit US soil first. I won't.

Sebring, Tuesday July 12th. Just around the corner. I'm expecting Porsche, probably Cadillac and maybe Acura to be there but it's too early for BMW for sure.

[joeb]

Originally Posted by Coach Ep

Sebring, Tuesday July 12th. Just around the corner. I'm expecting Porsche, probably Cadillac and maybe Acura to be there but it's too early for BMW for sure.

That is soon, I'm not sure anybody has even had a rollout besides Porsche.

[tomcug]

https://sportscar365.com/lemans/wec/...letes-rollout/
As expected, looks nowhere near as cool as those promotional photos we've seen before.

[joeb]

Originally Posted by Coach Ep

Joe, I don't believe the post Petit test is mandatory as not all manufacturers might be ready to run their new car


The Daytona one early December most definitely is mandatory.





Sebring, Tuesday July 12th. Just around the corner. I'm expecting Porsche, probably Cadillac and maybe Acura to be there but it's too early for BMW for sure.

Originally Posted by joeb

That is soon, I'm not sure anybody has even had a rollout besides Porsche.

Originally Posted by tomcug

https://sportscar365.com/lemans/wec/...letes-rollout/
As expected, looks nowhere near as cool as those promotional photos we've seen before.

This is a great string of 3 posts where they all tie together nicely!



sent during haircut

[tux]

Hello, today Cadillac released a video of their car testing. Yes it sounds glorious.

https://twitter.com/CadillacVSeries/...ixM_l7gsuhK21g

[hondafan37]

Shakedown this week for the Acura ARX-06 LMDh

https://en.endurance-info.com/auto/a...arYjy0x9F-xRwY

[joeb]

Originally Posted by tux

Hello, today Cadillac released a video of their car testing. Yes it sounds glorious.



https://twitter.com/CadillacVSeries/...ixM_l7gsuhK21g

That does sound good, I'm just wondering if they could frame that shot any tighter so we get a smaller view of the car?

sent during haircut

[S griffin]

I do love the sound of it, certainly can't wait to see it driven in competitive anger. Great to have Cadillac in the series

[veeten]

Originally Posted by hondafan37

Shakedown this week for the Acura ARX-06 LMDh

https://en.endurance-info.com/auto/a...arYjy0x9F-xRwY

Can't wait to see and hear that car in action.
What Acura (Honda) should do is invite some teams to watch and get their reactions. It should make it easier for them to make, at least, 2 more to run in the WEC.

[seanyb505]

Hmm