IMSA Race Road America 2015

[J Jay]

Originally Posted by BullMan

Quite a strange maneuver. Pulled onto the grass on the left side of the circuit, then drove nearly 90 degrees across and stopped on the circuit on the right side.

I assume that he thought the car was going to stop just before the kink but as it rolled on he decided to get off the line. Otherwise I'm as clueless as you are on why he didn't just leave it in the grass.

[J Jay]

I'm surprised the 350Zs didn't work together to deal with Hindman off the restart. Yes Zacharias is catching the #13 Cayman but the 3-4 laps it took to get past the #46 and the sister car might cost them the win.

Edit - Yep, that's a race lost for Zacharias. Congratulations for the Rum Bum guys though, holding on just enough (!) at the end.

[MoMedic9019]

Originally Posted by Rcz

Seems so foggy today.

It's not foggy, so much as lightly hazy and overcast.

[Accident]

Ugh, as if it wasn't hard enough to avoid the Conti spoilers at SC365.

[Pandamasque]

BoP wins qualifying.

[jasonjessica09]

Originally Posted by Pandamasque

BoP wins qualifying.

The gap between the P and GTLM pole winners has shrunk by almost 3 seconds from last year to this year too.

[Artur]

Originally Posted by J Jay

Edit - I'm listening without sound so if it was something else ignore me.

how did you do that?

3s from P to PC, another 3s to GTLM and then, 7s to the GTDs

GTDs are too slow, imho. What's the reason for it, weight, power, something else?

[Deleted]

As with everything they've been bopped to perform at that level, are not full to GT3 yet, and also have crappy Contis against the confidentiality-Michelins/Falken in GTE

Wasn't the last time Ganassi got pole last year also the time when they were bopped to top in quali

[TF110]

Probably those pathetic tires and aero cuts. That Viper must be close to 1400kg.

[Rcz]

For fun the LMP900s of old seem to get around in the 1:51s to 1:54s. Never thought DPs would ever get so close. Imagine if they had those better tires.

[joeb]

The race should be exciting tomorrow if the conditions are wet or mixed. The protos were beyond slow yesterday in the wet which could put the gtlm cars at the sharp end if we see rain again.

[MoMedic9019]

Originally Posted by joeb

The race should be exciting tomorrow if the conditions are wet or mixed. The protos were beyond slow yesterday in the wet which could put the gtlm cars at the sharp end if we see rain again.

Rain is no longer in the forecast, which means, locally, it'll be a deluge.

[Mike Hedlund]

The track is around 2 seconds faster than last year because of the repaving.

-mike

[Artur]

Originally Posted by Chiana

As with everything they've been bopped to perform at that level, are not full to GT3 yet, and also have crappy Contis against the confidentiality-Michelins/Falken in GTE

What do you mean by confidentiality in GTE? Are the continental tires "open" in GTD? By open I mean as in LMP2 where the tire doesn't belong to the manufacturer, so rivals can access the product and research. I know that in LMP1 the tire has confidentiality, ie, Michelin owns all tires and they are all returned to them after used. They(Michelin) said, in a PR, that their LMP2 tires don't have the secret chemical ingredients because the regulation set the tires as open, meaning it can eventually end in a rival's hands.

Continental shouldn't be that bad, though. They are only behind Michelin, Bridgestone and Goodyear on profit and R&D investment. Falken Porsche qualified 1,5s behind Bamber(the other Michelin Porsche did no fast lap).

I can't believe Continental would be worse than Falken, unless the tire rule really means "open product"

I read this from Mike Hedlund, DragonSpeed Ferrari driver in Pirelli World Challenge :

“The GTLM and GT3 cars have a lot more downforce so you tend to roll a lot more speed through the entry and middle part of the corner compared to a GTD car. GTD cars tend to square off more corners in order to get rotated early and back to the power since they can’t roll the same speed through the corner. The horsepower and weight is very close between them all. Driver aids don’t help much in terms of lap time, just makes them easier to drive close to the limit.”

If the difference in downforce is that significant for lap time, I imagine how quick that Ford GT will be next year

Well. official numbers:
http://www.imsa.com/imsa101/car-classes

GTLMs are even heavier, but have 50HP more

Yeah, I think the Contis are really opened, ie, with poor compounds. 7s if too big even considering the other factors.

EDIT: Oh my, I wrote that before seeing the above post. What a coincidence!

I hope the quote is correct, Mike

[BullMan]

Originally Posted by Artur

What do you mean by confidentiality in GTE? Are the continental tires "open" in GTD? By open I mean as in LMP2 where the tire doesn't belong to the manufacturer, so rivals can access the product and research. I know that in LMP1 the tire has confidentiality, ie, Michelin owns all tires and they are all returned to them after used. They(Michelin) said, in a PR, that their LMP2 tires don't have the secret chemical ingredients because the regulation set the tires as open, meaning it can eventually end in a rival's hands.

Continental shouldn't be that bad, though. They are only behind Michelin, Bridgestone and Goodyear on profit and R&D investment. Falken Porsche qualified 1,5s behind Bamber(the other Michelin Porsche did no fast lap).

I can't believe Continental would be worse than Falken, unless the tire rule really means "open product"

I read this from Mike Hedlund, DragonSpeed Ferrari driver in Pirelli World Challenge :If the difference in downforce is that significant for lap time, I imagine how quick that Ford GT will be next year

Well. official numbers:
http://www.imsa.com/imsa101/car-classes

GTLMs are even heavier, but have 50HP more

Yeah, I think the Contis are really opened, ie, with poor compounds. 7s if too big even considering the other factors.

GTE is GTLM. IMSA just calls it something different for some reason. GTE tires may nearly all be Michleins, but each team has their own compound and tire makeup. That info is not shared. Continental tires are terrible pieces of crap. The series mandates that they have certain wear and grip characteristics. The Pirellis and Michelins a team can buy off the shelf and put on another GT3 car would blow the doors off the pitiful offering from Continental. Conti tires are spec tires. They're all the same. The different classes may have some differences though. I'm sure the P tire is different than the GTD tire.

Also, GTD cars are not real GT3 cars. They start out as GT3 cars, but the effective aero and driving aids are stripped from the cars. The aero pieces are replaced by useless junk from Crawford which means the cars have less drag, but less grip, so they're faster in a straight line, but not nearly as capable in the corners.

[Artur]

Originally Posted by BullMan

The Pirellis and Michelins a team can buy off the shelf and put on another GT3 car would blow the doors off the pitiful offering from Continental.

Do you know this for a fact or are speculating(and exaggerating with it)?

On the 24 of Nurburgring qualifying, the fastest car on Pirelli tires was a Bentley, which was 6s slower than the fastest Bentley on Michelins. They all run on 'closed' sets(tires returns to the manufacturer so that the secrecy in the compound is kept) afaik.

Can Pirelli, off shelf(which won't have their best compound which is already a lot slower than Michelin's to begin with), tires really "blow the doors" off the spec Continental?

If Contis are really this bad I think IMSA should do something about it and request a better product from them(I'm sure they are capable of and their street tires are usually among the top rated)

[HORNDAWG]

Originally Posted by Artur

Do you know this for a fact or are speculating(and exaggerating with it)?

On the 24 of Nurburgring qualifying, the fastest car on Pirelli tires was a Bentley, which was 6s slower than the fastest Bentley on Michelins. They all run on 'closed' sets(tires returns to the manufacturer so that the secrecy in the compound is kept) afaik.

Can Pirelli, off shelf(which won't have their best compound which is already a lot slower than Michelin's to begin with), tires really "blow the doors" off the spec Continental?

If Contis are really this bad I think IMSA should do something about it and request a better product from them(I'm sure they are capable of and their street tires are usually among the top rated)

It's a crock! The PCs got faster on the Contis vs the off the shelf spec Michelins they were on previously.






L.P.

[MoMedic9019]

Originally Posted by HORNDAWG

It's a crock! The PCs got faster on the Contis vs the off the shelf spec Michelins they were on previously.

Because they were softer than the rocks Michelin was supplying.

Actual rubber versus granite is a big change.

[BullMan]

Originally Posted by Artur

Do you know this for a fact or are speculating(and exaggerating with it)?

On the 24 of Nurburgring qualifying, the fastest car on Pirelli tires was a Bentley, which was 6s slower than the fastest Bentley on Michelins. They all run on 'closed' sets(tires returns to the manufacturer so that the secrecy in the compound is kept) afaik.

Can Pirelli, off shelf(which won't have their best compound which is already a lot slower than Michelin's to begin with), tires really "blow the doors" off the spec Continental?

If Contis are really this bad I think IMSA should do something about it and request a better product from them(I'm sure they are capable of and their street tires are usually among the top rated)

Yes, it's a known fact that the tires Conti supplies are slow compared to pretty much everything else.

[Deleted]

We shouldn't really be blaming Conti for the crap product that their name is handing to teams.
a) They are made by Hoosier
b) NASCAR-IMSA doesn't care of quality control as long as the sponsoring marque in question pays them
c) The known P2 tire fiasco that the series is allegedly preventing the company from fixing
d) It's a spec tire so performance doesn't matter, it's not like the series is allowing actual contest between classes anyway

[HORNDAWG]

Originally Posted by BullMan

Yes, it's a known fact that the tires Conti supplies are slow compared to pretty much everything else.

No it is not, as there is/was clear evidence from within the ALMS in 13 on the LMPCs.






L.P.

[Accident]

Originally Posted by Artur

GTDs are too slow, imho. What's the reason for it, weight, power, something else?

Part of is who qualified the cars. Lindsey is an amateur driver, but with Pumpelly in the car it most likely would have been faster and a smaller gap to the GTE cars... How much smaller the gap would be I'm not sure of though.

[Mike Hedlund]

Originally Posted by Chiana

d) It's a spec tire so performance doesn't matter, it's not like the series is allowing actual contest between classes anyway

Actually, it does matter. Go look back at my twitter feed from a few weeks ago where I tested GTD Continentals and the PWC Pirellis (hard compound, same as what's ran in BES/BSS) on the same day on my 458 GT3 spec at Road Atlanta (along with the #63 GTD car running at the same time).

Continental probably could make a comparable tire, but they don't make enough different build/constructions (not compounds) of the same tire to work on different cars. The series is the only one to blame for that.

Also as for the quote of mine used above -- the GTD regs have changed considerably since the 2014 season began. The cars are much closer to GT3 spec now (minus the electronics and the joke of a rear wing).

-mike

[chernaudi]

It has to be said that the Michelin LMPC tires, from what I understand, were basically almost treadless (shaved) DOT-spec tires. Being based off road-legal compounds means that they'd take forever to wear out, but were seemingly made out of concrete by comparison with an actual race tire.

The Continental/Hoosier rubber is an actual race tire built for racing in terms of construction and compound.

And don't get confused with DOT-spec. That means that the tires use a tread compound (and probably other items) based off of a street legal tire, but the tire itself isn't well suited (and often are illegal) for street use. Hoosier make that disclaimer for their DOT-spec drag racing slicks.

[carbsmith]

Considering how close the FLM09 is to a full blown P2 car the low performance of its original spec tire was probably fairly intentional.