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[EX_stream_tuna]

wow, he really could be on to something.  His data and his theory intersect with my theory, which was that it was fitting the correct tire, but the wrong sub-type of tire.  The main correction being that it's possibly fitting the correct tire class/subclass, but not the correct wheel size and so less of a contact patch.  That would result in more noise and less grip, more heat and more wear!

It is extremely plausible that when PD fixed the tire width bug at the source where you actually fit the wheels on the car, they did not realize a similar fix needed to be applied to the pit-stops.

I'm going to msg MastrGT to make sure he sees your post, Chrome!

[MasterGT]

OK, I saved a copy of the screenshot, however, there are changes happening at the PSN now that will likely affect how I can or should report bugs. I hope to have this cleared up shortly, at least by tomorrow. Regardless, I will send this in ASAP.

[RoninTuna]

In the mean time I'll go through some of my replays with a fine tooth camera and see if the idea can be confirmed or denied visually.

[dlrws6]

I don't think it is the case.  At least not visually speaking.  I've taken photos of the 69 Camaro race car that I can post later.  Also the 2000 Camaro SS which I have been using as a test car has same size tires front and back.  I also question his results since he shows no info regarding tire wear.  I want to try and duplicate his results.

I might should also dig up my GTP user id and password.

More later gotta work now.

[EX_stream_tuna]

I don't think it is the case.  At least not visually speaking.  I've taken photos of the 69 Camaro race car that I can post later.  Also the 2000 Camaro SS which I have been using as a test car has same size tires front and back.  I also question his results since he shows no info regarding tire wear.  I want to try and duplicate his results.

I might should also dig up my GTP user id and password.

More later gotta work now.

Good point about the tire wear.  Maybe he was doing it with wear off and only looking at lap times.  Laptimes wouldn't suffer as much if wear was not on.

Maybe you could repeat his tests as closely as you can with wear on normal or fast?  I like the idea of using Motegi Speedway.  Seems scientific and shit.  (read, "controlled")

[dlrws6]

I don't think it is the case.  At least not visually speaking.  I've taken photos of the 69 Camaro race car that I can post later.  Also the 2000 Camaro SS which I have been using as a test car has same size tires front and back.  I also question his results since he shows no info regarding tire wear.  I want to try and duplicate his results.

I might should also dig up my GTP user id and password.

More later gotta work now.

Good point about the tire wear.  Maybe he was doing it with wear off and only looking at lap times.  Laptimes wouldn't suffer as much if wear was not on.

Maybe you could repeat his tests as closely as you can with wear on normal or fast?  I like the idea of using Motegi Speedway.  Seems scientific and shit.  (read, "controlled")

While working for the last 4 hours I’ve had some thoughts.
First off you make some good points Ex and it leaves me with some questions that I have not yet tried.  Can you change tires with the tire wear set to off?  If not is there any affect just going down pit road? Otherwise yes I would like to try and replicate the situation exactly and see if I get the same thing, plus check tire wear. I’ll have to go back and look but if he used Motegi speedway I have concerns about his data since it is a very wide oval and lap times can really vary depending on the driving line and I personally find it hard to be consistent there.
I actually think Daytona would be a better test track  to eliminate as many variables as possible but it can get real boring going around and around with no one else on track.

Also in regards to car performance PD may have given us the best tool to see what is going on pre vs. post pit stop.  The data logger, assuming it is possible to load a replay into it that has the tire wear bug in affect. I have not used it yet so I do not know its capabilities and limitations.

Perhaps I can play with this after the race tonight along with re-read his post to collect all the settings he used to test the cars.

In a way as long as you don’t dwell on the impact the bug has on racing, it is a fun little puzzle to try and sort out.

[EX_stream_tuna]

Thanks.

Loading laps into the data logger is tricky, because it only accepts "best lap replays", and so you'd have to probably do test drive mode, and make SURE that your best lap was the one that would reveal something useful in the editor.  Then, probably start a new session and make sure that new session's best lap is the other example you want to compare.

They should allow you to load up longer replays and isolate the laps you want to examine..

[dlrws6]

Thanks.

Loading laps into the data logger is tricky, because it only accepts "best lap replays", and so you'd have to probably do test drive mode, and make SURE that your best lap was the one that would reveal something useful in the editor.  Then, probably start a new session and make sure that new session's best lap is the other example you want to compare.

They should allow you to load up longer replays and isolate the laps you want to examine..

That would be nice, but I think I can work with Best lap replays as long as the modes they are available in will allow me to change tires.

[no_affiliations]

The most intriguing, and seemingly easily most replicable,  thing  I see here is the change in speed vs. RPM.  A change in top speed would indicate change in wheel (or tire) size, since no other driveline changes are apparent.  Or a bug with calculation of tire/wheel sizes.  Or something related but much more complex.

[EX_stream_tuna]

The most intriguing, and seemingly easily most replicable,  thing  I see here is the change in speed vs. RPM.  A change in top speed would indicate change in wheel (or tire) size, since no other driveline changes are apparent.  Or a bug with calculation of tire/wheel sizes.  Or something related but much more complex.

someone (I believe in the PSN thread dealing with this topic) mentioned the very physics-based possibility that the RPM differences and top speed are related to decreased grip during accel, therefore less accel.  That matches perfectly with the increased tire noise.

[no_affiliations]

The most intriguing, and seemingly easily most replicable,  thing  I see here is the change in speed vs. RPM.  A change in top speed would indicate change in wheel (or tire) size, since no other driveline changes are apparent.  Or a bug with calculation of tire/wheel sizes.  Or something related but much more complex.

someone (I believe in the PSN thread dealing with this topic) mentioned the very physics-based possibility that the RPM differences and top speed are related to decreased grip during accel, therefore less accel.  That matches perfectly with the increased tire noise.

Physics based how?  Acceleration and top speed are different things.  Changing the outer diameter of the wheel and tire changes the relationship between RPMs and speed.  I guess the proposal is that the tires are slipping even at maximum speed, but constant slippage would destroy these tires with heat way faster than is being seen.  If the proposal is that they aren't slipping but somehow apply less power, they wouldn't reach the RPM limit, they would simply stop accelerating at a lower speed, with an RPM relative to that speed. 

[EX_stream_tuna]

The most intriguing, and seemingly easily most replicable,  thing  I see here is the change in speed vs. RPM.  A change in top speed would indicate change in wheel (or tire) size, since no other driveline changes are apparent.  Or a bug with calculation of tire/wheel sizes.  Or something related but much more complex.

someone (I believe in the PSN thread dealing with this topic) mentioned the very physics-based possibility that the RPM differences and top speed are related to decreased grip during accel, therefore less accel.  That matches perfectly with the increased tire noise.

Physics based how?  Acceleration and top speed are different things.  Changing the outer diameter of the wheel and tire changes the relationship between RPMs and speed.  I guess the proposal is that the tires are slipping even at maximum speed, but constant slippage would destroy these tires with heat way faster than is being seen.  If the proposal is that they aren't slipping but somehow apply less power, they wouldn't reach the RPM limit, they would simply stop accelerating at a lower speed, with an RPM relative to that speed. 

ummm... because time is a factor?  If you don't accelerate it takes an infinite amount of time to reach top speed.

[no_affiliations]

If time's the factor, it would not achieve the same RPM.  Same RPM with less speed = change in driveline/tire outer diameter.  Less RPM with less speed = less acceleration.  If the problem is slippage, there should be some acceleration still happening as the wheel speed equals the engine's speed, if it's lack of acceleration the RPMs should be lower.  There's no physics-based reason for it to be otherwise. 

[dlrws6]

I have not yet recreated the test from the planet but since I had to do some racing at Daytona I decided to play around there. Also it turns out that you can still change tires even wear turned.  Below is my spread sheet of the results at Daytona without tire wear... yes I ran out of paper.




Up next a photo study of a messed up car.

Edit: Strike that. Its more trouble than I thought it would be. 

[EX_stream_tuna]

If time's the factor, it would not achieve the same RPM.  Same RPM with less speed = change in driveline/tire outer diameter.  Less RPM with less speed = less acceleration.  If the problem is slippage, there should be some acceleration still happening as the wheel speed equals the engine's speed, if it's lack of acceleration the RPMs should be lower.  There's no physics-based reason for it to be otherwise. 

possibly.  I was reading the suggestion as meaning that they were not reaching the top speed or top RPM they were in teh same race, same straights.  If that's the case, though, it could merely be that there wasn't enough time to get enough speed or top gear into max RPM by the time they had to begin braking.

Again, just a misunderstanding of what the other was trying to type.  I wish it wasn't so easy for this to happen