Historic Group C/GTP - Pre-Season Tyre Test

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Tyre King
Yeah I agree with that assessment Marty!

I am going to suggest just that ammendment to Chris in the LMS.
My GT-One would be pitting every two laps, even with hard boots on the rear, at Le Sarthe and maybe every lap at the Ring.:crazy:

I've been running these cars @ 1.065 Hp/Kg as that figure is stock for two of them.
Jag - 894Kg / 914Hp (std) / 951Hp in test (Spot on @ 1.064) - 2'53.682
89C - 900Kg / 908Hp (std)/ 954Hp in test (Slightly low @ 1.060) - 2'53.259
92CP-900Kg / 939Hp (std)/ 958Hp in test (1.064) - 2'53.363
88C - 850Kg / 906Hp (std) / 906Hp in test(stock @ 1.065) - 2'53.372*
C9 - 893Kg / 927Hp (std) / 955Hp in test (slightly high @ 1.069) - 2'51.858
787 - 830Kg / 791Hp (std) / 886Hp in test (slightly high @ 1.067) - 2'51.373
905 - 750Kg / 799Hp (std) / 799Hp in test (stock @ 1.065) - 2'57.746*

* no changes to P/W figures
Neil
Click to expand...

Could i suggest .. there are 4 cars that need to have their ptw ratios .. ''adjusted'' .

88CV should be : 892kg/951hp .. 1.066
C9 should be : 901kg/955hp .. 1.059
787 should be : 896kg/949hp .. 1.059
905 should be : 825kg/870hp .. 1.054
 
Could you include some times to back up the adjustments, please Phil?

Bare in mind the figures you have quoted from me are not the adjusted one's after Le Sarthe testing, they are the initial ones at the start of testing there.
These are the ones that were adjusted.
Car__weight__Power__Hp/Kg

Jag - 894Kg / 951Hp - 1.064
89C - 900Kg / 954Hp - 1.060
92CP-900Kg / 958Hp - 1.064
88C - 850Kg / 906Hp - 1.065
C9 - 928Kg / 945Hp - 1.018
787 - 805Kg / 815Hp - 1.012
905 - 750Kg / 918Hp - 1.224

Neil
 
This is my observation:

1. cars that exhibit excessive tire wear need the kg. reduced until it is compatibile with others

2.cars that seem to be too good on tire wear and may have an advantage...increase kg.

Tire wear needs to be balanced so all cars not only pit equally but also that the handling on the laps just before pitting are pretty equal. Example: ...part of the Jag's problem was tire wear on lap 4 was off, and the car was almost undriveable on the pit in lap (5). Times on the pit in lap and lap 10 were 4- 5 seconds slower than the previous laps.

Reducing the initial kg setting corrects that tendency.
 
Hello Guys! I seemed to have struck good luck as I found wireless internet at the hotel I'm staying at. Only trouble is that my time is limited, so my posting is limited too. Anyhow, how's the testing with the Minolta Toyota been?
 
Tyre King
Could you include some times to back up the adjustments, please Phil?

Bare in mind the figures you have quoted from me are not the adjusted one's after Le Sarthe testing, they are the initial ones at the start of testing there.
These are the ones that were adjusted.
Car__weight__Power__Hp/Kg

Jag - 894Kg / 951Hp - 1.064
89C - 900Kg / 954Hp - 1.060
92CP-900Kg / 958Hp - 1.064
88C - 850Kg / 906Hp - 1.065
C9 - 928Kg / 945Hp - 1.018
787 - 805Kg / 815Hp - 1.012
905 - 750Kg / 918Hp - 1.224

Neil
Click to expand...

Neil,

Yes, the above P/W settings are what I have been using for the GVS testing.

Increasing the Jag's P/W ratio from 894Kg/951HP will be necessary in order for it to remain competitive. However, at 804Kg/904HP, the Jag exhibited 3rd gear wheel spin and spun out on a few turns where previously it had not.

So, I compromised by reducing both Kg and HP to 876Kg/932HP. At those settings, the Jag is both faster and has a bit better tire wear. P/W ratio at these settings is 1.064.

I have no individual lap times, however, I was able to improve my final time by 10 secs when compared to our initial settings of 894/951. I also tested at 804/904, but again, with my driving style, the P/W was too much for me to handle and the Jag would spin out.

I'm surprised that the Jag seems to wear its tires out so quickly for Gt3E. I must not be pushing as hard. My style is to push the car as fast as possible without causing excessive tire wear. Then again, I'm always finish near the bottom of the lineup. :ouch:

Phil
 
I agree with both of you on the adjustments needed for the Jag to be competative with the other cars.

I have (like Phil) have been playing with the weight of the Jag to get better tyre-wear. The problem is, that you also have to decrease the Hp by the right amount, or the tyres burn faster than before.

So,
I have kept the P/W ratio @ 1.064 and recalculated it for every reduction in weight.
The results are ambiguous at best.
As the weight drops off, the handling improves, and so does the tyre-wear(slowly), but as the power drops in tandem the lap times don't actually get any faster.
I think that the only way to get this car competative, is to give it enough power to keep up, and use harder tyres on the rear.

I know that may sound stupid, and counter-productive, seeing as most are saying that it is a tail happy b;tch to drive at the best of times.
But I drove the MacLaren last season, all season long I was having problems with the rear tyre-wear if I tried to use the same compound front and rear.
So I decided to use harder rears and learn how to drive the car that way.
And I didn't do badly at all (even if I do say so myself)

It just takes a little getting used to, and it makes the car oversteery, BUT, it also means that the car corners like a dream. You just have to moderate the throttle a little better than if you are on mediums, on the exit of corners.
But overall, the improvement in lap times is worth the extra effort and care required.

If you find that your fastest laps in the Jag, are when the fronts are green, and the rears are yellow, then you will find having harder rears on the beast is very similar in feel. The rear drifting slightly in the corners negates the understeer, and the car goes round corners faster.

Try it, you'll see what I mean. Unless it's my tyre-king driving style that lets me do this, not the actual physics of the thing, then you won't! ;)

Neil
 
ERacer
Updated test results for Grand Valley Speedway Test (fastest-to-slowest):

Toyota 88C-V (850Kg/906HP) - final time 16'47.344

Sauber C9 (928Kg/945HP) - final time 16'52.722

Mazda 787B (805Kg/815HP) - final time 16'54.530

Nissan R92CP (900Kg/958HP) - final time 16'56.149

Jaguar XJR-9 (894Kg/951HP) - final time 17'19.036

All cars set at RM/RM (strong tire wear), 350 gearing, pitted at end of lap 5.

Based on these settings, at this course, the Nissan R92CP, Sauber C9 and Mazda 787B match up well.
Click to expand...

EDIT: Jaguar XJR-9 (876Kg/932HP) - final time 16'53.044

And now the Jag matches up well. This also resulted in comparable, if not better, tire wear than the other above cars. Again, based upon my driving style. The only car in my test which ran significantly faster was the Toyota. I would be happy in the Jag at 876/932 knowing I may need harder tires for the longer races.

We still need to fine tune the Toyota, but otherwise I'm satisfied with the Jag at 876/932 and the other cars at the above P/W settings. Perhaps we should put all the cars through one more test at a different track before the series begins.

Any thoughts? 👍
 
Well, that's better than it was, for sure.....still needs a dose of power added to bring it on par.

I've been running 16:30's with the Jag.....that's why the tires wear a lot faster, if I slowed down to 16:50's, I'm sure it would act totally different in almost every way. But, I'm running a pace that suits me and that I'm comfortable with in all the cars.....trying to use the same pace with each of them.

I'd like to run some of the other cars later, but based on what others are doing, there are still two cars that seem to have a clear advantage. I think I'd add weight to both of them for starters.:) 💡
 
Gt3Emperor
Well, that's better than it was, for sure.....still needs a dose of power added to bring it on par.

I've been running 16:30's with the Jag.....that's why the tires wear a lot faster, if I slowed down to 16:50's, I'm sure it would act totally different in almost every way. But, I'm running a pace that suits me and that I'm comfortable with in all the cars.....trying to use the same pace with each of them.

I'd like to run some of the other cars later, but based on what others are doing, there are still two cars that seem to have a clear advantage. I think I'd add weight to both of them for starters.:) 💡
Click to expand...

Sounds good! Let us know how you make out with those two cars. 👍

ERacer
 
Just managed to get a 16'24.952 in the Jaguar! :)

Absolutely on the limits of the rear tyres, made a couple of minor mistakes, but no big ones.

These are the settings I used, RM/RM, 250(ahem! I mean..) 350Kph, +3% power @ 941 Hp, -6 Wt @ 840 Kg, P/W ratio @ 1.120 Hp/Kg, NO TCS.

Still a real handfull, and really took all of the Tyre-King in me to keep the rears from spinning up.
Here's the splits and tyre info.....

L1 - 1'42.723 - rears green by 1st tunnel, fronts still cool at end of lap.
L2 - 1'35.156 - both now green, but fronts being cool at start cost time.
L3 - 1'34.474 - rears light green, fronts still green.
L4 - 1'34.171 - rears now yellow, fronts still green.
L5 - 2'00.253 - rears now red/orange and losing traction by T2, fronts yellow,
Pitted, wheels up @ 8'12 ish.
L6 - 1'43.536 - From now on everything to do with the tyres is 3/4 lap later.
L7 - 1'33.358
L8 - 1'33.753 - missed apex at entry to 1st tunnel, hense lost .4
L9 - 1'33.585
L10- 1'33.944 - rears just starting to go off at final corner.
Total : 16'24.952!

Some else please test these setting and see what you think.

Neil
 
I better go back and check my settings on the Minolta, they're the stock settings right, cause I ran a 16'16.xxx last night with RM/RM's and one pit. Somehow there's something wrong, maybe I changed the weight but I don't remember doing so. Oh well, I'll just rerun again tonight, double check my HP and weight. I'm allowed one hour a day in the seat for the next week or so.
 
Drew22
I better go back and check my settings on the Minolta, they're the stock settings right, cause I ran a 16'16.xxx last night with RM/RM's and one pit. Somehow there's something wrong, maybe I changed the weight but I don't remember doing so. Oh well, I'll just rerun again tonight, double check my HP and weight. I'm allowed one hour a day in the seat for the next week or so.
Click to expand...

Yeah mate, that car should be stock, according to the testing at Le Sarthe.

Minor adjustments may need to be done after this test, I'll give that one a go now.

Neil
 
Yeah, I ran a 16'16.845, hotlap of 1'32.199, I know the HP was correct but can't verify weight. We won't have that problem in GT5 since all race times, weights and HP are automatically uploaded. At least that's how GTHD is.
 
It's nice to see you back in the seat man !
I've yet to turn a wheel in this thing since we left the short course. The guys have been doing one hell of a great job on the testing aspect... bueno amigos ! ... now it's time to go see what the Mazda and I do compared to the rest of you mugs !
 
Drew22
Yeah, I ran a 16'16.845, hotlap of 1'32.199, I know the HP was correct but can't verify weight. We won't have that problem in GT5 since all race times, weights and HP are automatically uploaded. At least that's how GTHD is.
Click to expand...

I think that some weight added is the order of the day, I have comparable lap-times as you do Andy. Approx 1 second faster a lap than the Jag, but the tyre wear is even worse than the Jag IMO.

The extra weigh should have two benefits, it should slow it down some in the corners (cos this thing is really front-end grippy), and it should also improve the rear tyre life by reducing the P/W ratio.

I'll keep trying.

Neil
 
Just spent the last while trying, and I mean trying, to get the tyre wear/performance balanced in the Minolta.

Nearest I can get it, lap-time wise, to the Jag is 816Hp/850Kg.
And the race time would be comparable too, if I could finish a race that is.

Can I buggery get the rear tyres to last more than 4 3/4 laps before the thing is running on the rims!
Even with TCS on, I can get the first 5 laps in (really twitchy on last 1/3 of L5), but keep crashing out on the final lap (no doubt pushing too hard in the first half of the lap and using up the last of the tyres:dunce: ).
Torque and chatter are the problem, and I can't think of any way to get rid of the chatter.
The torque can be reduced by lowering the Hp, but then it isn't competative anymore.

I'm stumped! Sorry guys!:guilty:

Neil
 
To all who are testing these beautiful cars: Firstly, a huge 👍. As frustrating as it has been, especially for this first-timer, it has been an interesting and fun learning experience .... but it ain't over, yet. :banghead:

Grand Valley Speedway is a good test course - all types of turns, curves and a good straightaway too! GVS is also a tire-burner track, which is good for tire testing purposes.

Secondly, it may help our "equalizing" efforts if we step back a bit:

1. Even if all seven cars are equalized at GVS, we will not be able to equalize all seven cars for each and every track in this series.

2. Each car has a unique and irremovable set of characteristics, which may be an advantage or disadvantage depending upon the course being raced.

3. Over the course of the series each car should have a shot at the podium as long as we are both reasonably close in our equalizing efforts and mindful of each car's inherent characteristics.

Keep in mind, we just need to close the "inequality gap" a bit as each car has some equalization built into it which, over the course of the entire series, should give each car a good chance at a podium.

Example: the stock Toyota is fast and grippy and the stock Jaguar is slow and sloppy in comparison. But, there is a great equalizer already programmed into both cars - tire wear. So, its like the tortoise and the hare. We just need to be sure the gap is not too wide between the cars.

A huge thank you to both Neil and Darrell for providing the various P/W settings along with detailed lap times and vehicle stability analysis. :cheers: :cheers: I will defer to their tuning abilities.

Its important that everyone take out as many cars as possible and help with feedback and suggestions. Try out different P/W ratios.

Please refer to below P/W settings which are the adjusted initial settings for GVS, and which are currently being evaluated. Adjustments can always be made as the series progresses.

Toyota 88C-V (850Kg/906HP) - final time 16'47.344

Sauber C9 (928Kg/945HP) - final time 16'52.722

Jaguar XJR-9 (876Kg/932HP) - final time 16'53.044

Mazda 787B (805Kg/815HP) - final time 16'54.530

Nissan R92CP (900Kg/958HP) - final time 16'56.149

All cars set at: RM/RM, strong tire wear, 350 gearing

All cars had to pit end of lap 5.

* Please note, the Pug 905 and Nissan R89CP are missing as I do not own either car :( *


Respectfully,
ERacer
 
Del will do some proper testing of the 89C , C9 , 88CV and the 787 .. at what i think the ptw should be .. with all carrying roughly the same weight .

RL duties have kept me away from the PS2 for tooooo long ; but will get the laps in when i can .
 
Yeah, I'll be trying to get a little more time in here. I've been away in the GTPLMS Sonoma race trying to get a foothold established there. And a few other loose ends needed tidying.

Tyre King: I think you're on the right track with the Jag maybe a slight dial back on power might be in order. The Toyota tire problem maybe solved with a slight weight reduction. How are your times comparing between all the cars you've tested? Are they all close to compatible?

I agree with you, ERacer. Except, I believe the cars should be made as close as possible in overall times and tire wear at a common track like GVS and after that.....It's open to whatever the driver and track conditions dictate to adapt to the other circuits.
 
Gt3Emperor
I agree with you, ERacer. Except, I believe the cars should be made as close as possible in overall times and tire wear at a common track like GVS and after that.....It's open to whatever the driver and track conditions dictate to adapt to the other circuits.
Click to expand...

I agree with that 100% 👍
 
Jaguar testing Tyre King's suggested sets:

(840kg/941hp)

1:42.294
1:34.535
1:34.011
1:34.431
1:57.880 pit in

Tyre King's settings are pretty close to what's needed to put the Jaguar on fairly even footing with the rest of the field. My pace was pretty similar to his and it is closer to my test of the Nissan R92CP and the Toyota Minolta.

It's still a difficult beast to handle, but it's tire wear is comparable and it's pace is good. I'd vote for something pretty close to this for the Jag.

I'll run some more laps tomorrow.....my concentration is spent for tonight.

I'd hate to see any car be totally uncompetitive.:)
 
Took the Jag out at 941HP and 840Kg. It was difficult to keep from spinning out. I like to accelerate out of the apex but at those settings I kept spinning out of the turn. So, (+3) HP and (-3) Kg worked a bit better for me. However, not sure if speed is on par at +3 & -3.
 
After consultation with Nitro, this series will now be administrated by myself and ERacer.

Don't panic!

All will be well, just remember to always carry a towel.

More announcements in a day or so!

Neil
 
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