IMSA 2018 Roar Before the Rolex 24 - Jan. 4-7

[joeb]

Combined session laptimes can be seen here

http://results.imsa.com/Results/18_2...by%20Class.PDF

9/11 top times were Caddy's.

The new slower Caddy's have beaten last year's pole time by over a second. Don't recall conditions during that session.

[joeb]

Core got dinged with a sandbagging penalty for sandbagging because Bennett was too slow. Wtf? He doesn't have the same pace, the team wasn't being slow on purpose.

http://sportscar365.com/imsa/iwsc/da...ay-notebook-2/

[broadrun96]

Well they don't do it from on track speed do they? Thought they required access to the team electronics and decide on management restrictions from that info?

Maybe Core just isn't as good at it as Penske/Joest/ESM/etc?

[Accident]

Originally Posted by canaglia

Best solution: IMSA should force GM to drop the V8 and suggest them to use the V6 twin turbo from the cadillac gt3.

No.

[FormulaFox]

Originally Posted by canaglia

BTW can someone confirm if this pic tells the truth?



is daytona speedtrap placed so far away from first corner brake point ?

Speed traps have to be set far enough back to be sure they catch everyone before braking to get anything close to accurate data. It is rare the speed trap that can truly catch the fastest cars at their top speed - especially the fastest cars in a multi-class series.

I don't specifically know if that's the speed trap's location, but it makes sense for it's location to me. Far enough away from the braking zone to get everyone, close enough to it that most cars will be as close to their top speed as possible.

[Purist]

Also, given how close they are to V-max anyway, and the degree of the curve in the tri-oval, most cars aren't going to pick up much more speed after that trap location.

And I was just thinking about it again, but going back to the last time Prototypes ran these times on the road course, I think the exit of the chicane was slower in 1992-93. (They adjusted it for the 2003 season.)

[joeb]

Originally Posted by broadrun96

Well they don't do it from on track speed do they? Thought they required access to the team electronics and decide on management restrictions from that info?

Maybe Core just isn't as good at it as Penske/Joest/ESM/etc?

Good point. And I misread what I read earlier thinking Bennett was the one driving. But that being said..... I would like to know what exactly raised the suspicion of the officials.

[Lagunaseca_4life]

Something doesn't feel right about esm's and penske's performance.i think they should of done better,especially esm given how well they ended the season.

[Articus]

Originally Posted by Lagunaseca_4life

Something doesn't feel right about esm's and penske's performance.i think they should of done better,especially esm given how well they ended the season.

It's debatable what the value of this experiment was other than the pit stalls. On the one hand you have Felipe Nasr driving like he's got absolutely nothing to lose (for better or worse...) and then you have teams like Penske, ESM who just quite frankly are not interested in destroying a car in the barriers for the sake of some pit stalls. Could some people have gone faster, sure. I don't think the Penske, ESM, Mazda drivers drove that session like it was F1 Qualifying at Monaco. Whereas Nasr did. and track temps can play a role with the various setups. You cannot force anyone to go faster than what they are comfortable with.

[Purist]

To say nothing of the fact that Daytona is kind of an outlier in terms of the tracks in IMSA, or in top-tier sportscar racing, period. It's like Le Mans in that respect, though for some different reasons, but both do have a large proportion of the lap taken up by unusually long straightaways/flat-out stretches.

My point is, performance and setups at Daytona won't really be totally applicable anywhere else on the calendar.

[Turbodcc]

Are there any top speed results from the weekend?

[Victor_RO]

Originally Posted by Turbodcc

Are there any top speed results from the weekend?

http://imsa.alkamelsystems.com/Resul...actice%207.PDF

[knighty]

is there a web link to the boost figures that IMSA allowed the turbo cars to run at the test?........think I found it:

https://competitors.imsa.com/sites/d...vision_1_0.pdf

Acura 3.5L V6 = 1.769 BR......resultant capacity = 6.19L

Mazda 2.0L I4 = 2.661 BR......resultant capacity = 5.32L

Nissan 3.8L V6 = 1.832 BR......resultant capacity = 6.96L

So based on that it looks like Mazda over-achieved with a small capacity engine, and Nissan have a potentially very powerful engine.......the Acura is allowed to hold max boost for a very long time (4400-6000rpm), but the others are just allowed a single peak, 7150rpm for Mazda, and 6000rpm for Nissan

Dare I say Nissan and Acura may be holding back a bit.

[canaglia]

nothing strange, is quite normal that small displacement engine needs more turbo boost.
At the end considering that the engine revs up to 8800rpm (after that basically the engine becomes NA) guess that torque max release of AER-mazda engine should be in the range of 520-540Nm between 6500-7500rpm. If you ask me, unlikely the engine pushes 600hp.

Nissan and HPD figures should be very similiar; both in the 640-650Nm range. HPD keeps max torque release for longer, nissan gets some extra Nm

[Makaze]

Penske holding back about 1/2 second(my educated guess) but that still puts them down 1/2 second.(Honda needs a little more boost lower in rev range or less weight)

At Daytona the LMP2 and Turbo Engine DPi needs to be about .1-.15 faster than Caddy DPi in qual to have a chance in the race because in race trim and traffic the Caddy is going to be a beast.

[carbsmith]

Ideally the speed trap would probably be slightly closer to the tri-oval, but that's pretty much as deep as you can put it without the trap times being warped by what line a car is using anyways.

[canaglia]

Originally Posted by Makaze

Penske holding back about 1/2 second(my educated guess) but that still puts them down 1/2 second.(Honda needs a little more boost lower in rev range or less weight)

At Daytona the LMP2 and Turbo Engine DPi needs to be about .1-.15 faster than Caddy DPi in qual to have a chance in the race because in race trim and traffic the Caddy is going to be a beast.

Honestly how can you improve so much lmp2 performances?
oreca 07 didn't get any development/updates and ligier and dallara (riley/multimatic is a joke) got waiver just to achieve, at best, the same oreca level.
To me is quite unlikely that lmp2 can do better than mid-high 1.36.
The only help can come from bop if IMSA decides to cut 30kg, making 900kg the min. weight for lmp2 and give extra ballast do cadillacs.

[Akrapovic]

Better hope the Caddy isn't sand bagging, lol.

[kvenom]

Even if they aren’t the torque advantage is going help them immensely

[TF110]

Originally Posted by canaglia

Honestly how can you improve so much lmp2 performances?
oreca 07 didn't get any development/updates and ligier and dallara (riley/multimatic is a joke) got waiver just to achieve, at best, the same oreca level.
To me is quite unlikely that lmp2 can do better than mid-high 1.36.
The only help can come from bop if IMSA decides to cut 30kg, making 900kg the min. weight for lmp2 and give extra ballast do cadillacs.

Tires and setup. Understanding of the car will give you more time. Tires don't seem to be on the table for improving so the setup is left. But that's somewhat limited as well with the specific wing angles etc.

[MaskedRacer]

If there is no rain for the 24 race itself. I think we could be in a for a run with few safety car periods. No LMPC cars certainly helps. It seemed that those machines would stall easily. Where as DPI, GTLM, and GTD. If a car spins or gets in trouble they can get back to the pits. With that and the intense pace that the leaders will set, there could be a decent attrition rate in prototype and GTD especially. We got a 50 car grid to start and it could finish with under 34 cars maybe just due to mechanical attrition.

Everybody praises the reliability of the cars now which is true, but lets test them when they don't get a break from having safety cars every hour.

[joeb]

Originally Posted by MaskedRacer

If there is no rain for the 24 race itself. I think we could be in a for a run with few safety car periods. No LMPC cars certainly helps. It seemed that those machines would stall easily. Where as DPI, GTLM, and GTD. If a car spins or gets in trouble they can get back to the pits. With that and the intense pace that the leaders will set, there could be a decent attrition rate in prototype and GTD especially. We got a 50 car grid to start and it could finish with under 34 cars maybe just due to mechanical attrition.

Everybody praises the reliability of the cars now which is true, but lets test them when they don't get a break from having safety cars every hour.

Interesting point about attrition increasing with fewer cautions. I'm not so sure we will see fewer cautions. I think we will continue to see a lot of cautions due to the pro drivers in Protos and GTLM taking a lot of chances to stay ahead (or with) the competition. There are so many competitive entries in protos that they will be fighting hard to get around lapped traffic and there are bound to be some coming togethers.

[joeb]

IMSA released the pit and garage allocations based on Roar qualifying.

http://sportscar365.com/imsa/iwsc/im...-for-rolex-24/

Penske chose not to have their 2 cars next to each other in case they need to come in at the same time.

[Akrapovic]

Some interesting choices for pit slots, yeah. CORE at the front is nice.

I did a couple of fun articles about what we learnt during the Roar. It's just testing, but it's worth speculating about.

http://theracingline.net/2018/imsa/w...rn-prototypes/
http://theracingline.net/2018/imsa/w...-24-learn-gts/

[Damian Baldi]

Originally Posted by Akrapovic

Some interesting choices for pit slots, yeah. CORE at the front is nice.

I did a couple of fun articles about what we learnt during the Roar. It's just testing, but it's worth speculating about.

http://theracingline.net/2018/imsa/w...rn-prototypes/
http://theracingline.net/2018/imsa/w...-24-learn-gts/

Nice articles, thanks for sharing them.

On the prototypes side, I think both Ligier and Nissan didn't get much improvement from the aero update. Who knows why, maybe they need to find a different setup yet, or the upgrade desn't help for Daytona, but it works on twisted tracks. Both kind of cars were a bit far from the top. Another mistery for the list of hiden truths.