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      05-14-2018, 09:28 AM   #89
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I got clarification on the difference between the shaft compression and the HS compression. (High speed is on the remote canister)

Basically, I was told, that the shaft adjustment for compression is for changing grip & balance, and the high speed knob is use for controlling the movement of the chassis on bumps and jumps.

Because I am looking for "grip" and NYST is pretty smooth, I will keep the HS on F-4 and R-2 and will be experimenting with the shaft compression.

So next track days are June 2nd and 3rd
The plan for the morning sessions first day is to increase shaft compression on the front one click per session starting at click 4 until I can detect a difference. Then put front back to 4, and do in the afternoon same for the rear.

The plan is flawed because the relationship between the front and the rear are linked. But it is good enough to understand the effect of the shaft compression settings.

As a reminder, the goal is to improve the slow 40mph turns at NYST.
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      05-14-2018, 12:06 PM   #90
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Quote:
Originally Posted by rhyary View Post
I got clarification on the difference between the shaft compression and the HS compression. (High speed is on the remote canister)

Basically, I was told, that the shaft adjustment for compression is for changing grip & balance, and the high speed knob is use for controlling the movement of the chassis on bumps and jumps.

Because I am looking for "grip" and NYST is pretty smooth, I will keep the HS on F-4 and R-2 and will be experimenting with the shaft compression.

So next track days are June 2nd and 3rd
The plan for the morning sessions first day is to increase shaft compression on the front one click per session starting at click 4 until I can detect a difference. Then put front back to 4, and do in the afternoon same for the rear.

The plan is flawed because the relationship between the front and the rear are linked. But it is good enough to understand the effect of the shaft compression settings.

As a reminder, the goal is to improve the slow 40mph turns at NYST.
Do have the black m3 with m stripes on the side and gts wing by an chance?
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      05-14-2018, 12:21 PM   #91
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Quote:
Originally Posted by cherry-m3 View Post
Quote:
Originally Posted by rhyary View Post
I got clarification on the difference between the shaft compression and the HS compression. (High speed is on the remote canister)

Basically, I was told, that the shaft adjustment for compression is for changing grip & balance, and the high speed knob is use for controlling the movement of the chassis on bumps and jumps.

Because I am looking for "grip" and NYST is pretty smooth, I will keep the HS on F-4 and R-2 and will be experimenting with the shaft compression.

So next track days are June 2nd and 3rd
The plan for the morning sessions first day is to increase shaft compression on the front one click per session starting at click 4 until I can detect a difference. Then put front back to 4, and do in the afternoon same for the rear.

The plan is flawed because the relationship between the front and the rear are linked. But it is good enough to understand the effect of the shaft compression settings.

As a reminder, the goal is to improve the slow 40mph turns at NYST.
Do have the black m3 with m stripes on the side and gts wing by an chance?
I do
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      05-14-2018, 03:08 PM   #92
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Check out tire deflections on Fast right corner.
A 275 is flexing so that the rim is actually sticking out. Perhaps this is what road tires do or just cheap ones?
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      05-14-2018, 03:48 PM   #93
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Originally Posted by rhyary View Post
Check out tire deflections on Fast right corner.
A 275 is flexing so that the rim is actually sticking out. Perhaps this is what road tires do or just cheap ones?
I was there Friday, and caught one of your spins before the hairpin in the back. Your rear looks really stiff.

I also caught some of your dirt after wheelie hill
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      05-14-2018, 03:55 PM   #94
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Quote:
Originally Posted by cherry-m3 View Post
Quote:
Originally Posted by rhyary View Post
Check out tire deflections on Fast right corner.
A 275 is flexing so that the rim is actually sticking out. Perhaps this is what road tires do or just cheap ones?
I was there Friday, and caught one of your spins before the hairpin in the back. Your rear looks really stiff.

I also caught some of your dirt after wheelie hill
Correct.
That was after I adjusted the rear one more click to see what happens. And it did :-)

On Friday I also had the rebound too slow, I already wrote about it above.
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      05-14-2018, 11:10 PM   #95
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If your throttle and brake data is somewhat accurate, might want to consider cleaning up your pedal inputs. Especially need to address the coasting. Make sure you slow the car enough so that you can be on the throttle at apex.

Unless you're trailbraking after a long straight into a throw away corner.

I wouldn't focus on corner speed. You probably could hit the apex on all of the those turns doing 50mph. The problem is you'd be scrubbing speed from the apex to exit so you're max speed on the next straight will be much lower. Let's say you take a late apex, you're at 35mph at the apex. It is likely that you'll have a higher max speed since you're on the throttle longer.

I would argue corner speed is semi irrelevant.

Quote:
Originally Posted by rhyary View Post
Check out tire deflections on Fast right corner.
A 275 is flexing so that the rim is actually sticking out. Perhaps this is what road tires do or just cheap ones?
Do what you must...how are you making judgements to tune your suspension when you clearly don't understand slip angle?

Again, fix the driving first...just my opinion. Just as a point of reference, I haven't touched the adjustments on my TC Kline Konis in over 50 track days.

https://en.wikipedia.org/wiki/Slip_angle
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      05-15-2018, 12:38 AM   #96
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while on the subject of tires, you mentioned using a tire pyrometer a few times and talked about temperature spreads. i've learned that temperature of the tire tread isn't super relevant. you basically have to come into the hot pits as you complete a hot lap and have someone right there waiting to take temps. even then, it isn't super important. mostly because by the time you come in, get your pyrometer out, etc., the tread temps have largely dissipated throughout the tire carcass. i was told this by a more experienced driver i met at a track day who actually had a tire pyrometer (longacre, very nice), and this was reaffirmed in a "tune your car's handling webinar" i listened to with ross bentley and jeff braun (experienced race engineer).
i was glad to become bestowed with this info before i dropped $300 on a pyrometer. it is a tool that has its place, but only if used properly. even when used properly, it is a small piece in the puzzle of tires, tire temps, and pressure.

the tire manipulation in the picture is normal and natural to an extent. since you're running 19's your margin of error is going to be slimmer on tire pressure. you have less sidewall to play with, and getting it just right is going to be tougher. its good that you are taking track temps and it sounds like you are really enthusiastic about it and have good attention to detail. keep it up and experience will come. don't be afraid to experiment with tire pressures as well.
another thing i learned in the suspension tuning webinar was an air dryer. it essentially uses a filtration device to take humidity out of the compressed air you are putting into your tires. this was nothing new, just something i hadn't thought of yet. another option is nitrogen, but that is a little more inconvenient than $25 worth of parts for the in-line air driver that goes on your compressor. since you already have all the other neat gadgets, this might be something to look into if you haven't already. drain and fill your track tires with the dry air and it should help deal with some fluctuations in temps.

i highly suggest you email ross bentley (speedsecrets.com) and ask him for access to the recent "tune your car's handling" webinar. you won't be able to ask questions (it was live), but the six hours of content is well worth it.
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      05-15-2018, 02:45 AM   #97
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The TrackAddict Brake indicator is calculated and very inaccurate. I think the throttle is more accurate. It is not Aim DL by any mean.

I am taking tire temps to see the distribution of heat across the the 275 to verify camber. especially on the passenger front. regardless of the correct temp, do you think the tire surface cool in significantly different between the inside and outside?

All the comments about my driving are accurate and I am working on it. I am slowing too much into the corners. I am practicing by running higher gears so I can hit the gas and not worry about spinning out. I hit turn 18 multiple time at 48mph and there is no reason to take it below 50mph. Last year I was at 43-45 range. Same at turn 1, i am trail braking into it but too much. I trail brake into every corner. some just to establish habit, some for real.

I mainly practice now getting rid of cruising between off the brakes and on the gas. It is better then last year, but far far from perfect. I watched many YouTube videos in the winter that shows driver feet work.

I am not sure if this is a right approach but I take many laps mostly on 5th gear. That allows me to concentrate on entry speed and timing of brakes and gas. it turns the car into a Miata so no lap records.
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      05-15-2018, 05:09 AM   #98
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Quote:
Originally Posted by rhyary View Post
I am taking tire temps to see the distribution of heat across the the 275 to verify camber. especially on the passenger front. regardless of the correct temp, do you think the tire surface cool in significantly different between the inside and outside?
the race engineer in the webinar acknowledged the pyrometer as a tool in the right conditions if used properly. it was talked about as a small piece of the puzzle, but definitely not a tell-all tool. i was surprised he seemed to not utilize one at his level of expertise.
the biggest emphasis was correct tire pressure for the present track conditions. don't let a pyrometer (potentially being used in a less efficient manner) dictate camber.
don't be concerned if the passenger front is a little hotter. the info is useless since you would never run more camber on one side than the other. you're better off using that energy to pay closer attention to tire pressure.
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      05-15-2018, 06:07 AM   #99
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Quote:
Originally Posted by roastbeef View Post
Quote:
Originally Posted by rhyary View Post
I am taking tire temps to see the distribution of heat across the the 275 to verify camber. especially on the passenger front. regardless of the correct temp, do you think the tire surface cool in significantly different between the inside and outside?
the race engineer in the webinar acknowledged the pyrometer as a tool in the right conditions if used properly. it was talked about as a small piece of the puzzle, but definitely not a tell-all tool. i was surprised he seemed to not utilize one at his level of expertise.
the biggest emphasis was correct tire pressure for the present track conditions. don't let a pyrometer (potentially being used in a less efficient manner) dictate camber.
don't be concerned if the passenger front is a little hotter. the info is useless since you would never run more camber on one side than the other. you're better off using that energy to pay closer attention to tire pressure.
How do you quote only partial text?

I settled on 40psi hot coming off the track.
I tried 42,40,38 and 36

I understand that the temp and PSI measurs I am taking are not ideal since I have to come off the track into the paddock. But I don't have a crew coming with me to HPDE days. So it is what it is.

I guess I will never win my HPDE days, but that's ok. :-)

Being in the technology business for 30 years I am forced to learn new technology on a yearly basis. So I am not new to learning complicated, difficult, often complex dependency type issues. It is a second habit and fit my personality.

However, I prefer to learn on my own the first 50-75% and seek education, instruction and classroom for the last 20%. This way I have the context to absorb what I am been taught.
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      05-15-2018, 06:25 AM   #100
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once you hit the quote button, it takes you to the screen where you type your message. simply delete the text you don't want. i use it to keep posts shorter and more direct to what i'm responding to.

Quote:
Originally Posted by rhyary View Post
I understand that the temp and PSI measurs I am taking are not ideal since I have to come off the track into the paddock. But I don't have a crew coming with me to HPDE days. So it is what it is.
i know, that is the point. tire pressure is more telling and more important than a pyrometer reading across a tire's tread. tire tread temps can be off because of to much pressure. you can check with a pyrometer and adjust camber all day long and still have a tire pressure problem.

keep an eye on the tread grain and how the tire is wearing. is the outside edge getting chewed up (too little camber)? is the inside edge scrubbing away too early and you can't seem to brake like you used to (too much camber)? most of the time, this is a tire pressure issue.
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      05-15-2018, 09:24 AM   #101
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Tire treads are wearing evenly, finally, on all four. If you look at the picture I posted of the tires, you can see the patch is on the road pretty evenly. I am on the gas there. In the full picture you can see the inside tire is half the width on. At NYST the passenger front take most of the beating so switched left to right will even them out.

In the picture, I am doing this right hand segment
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      05-15-2018, 10:07 AM   #102
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Quote:
Originally Posted by roastbeef View Post
while on the subject of tires, you mentioned using a tire pyrometer a few times and talked about temperature spreads. i've learned that temperature of the tire tread isn't super relevant. you basically have to come into the hot pits as you complete a hot lap and have someone right there waiting to take temps. even then, it isn't super important. mostly because by the time you come in, get your pyrometer out, etc., the tread temps have largely dissipated throughout the tire carcass.
You want something like this which ties into an existing datalogger and actually reads tire temps across the entire width of the tire in real-time:

http://izzeracing.com/products/tire-...m-systems.html


Overlaying the temperature graphs with the other AIM data can really help you see the relationship between tire stress and a given corner. It's truly amazing.

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      05-15-2018, 12:42 PM   #103
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Sorry, but I think someone should really teach you some forum manners. You troll the shit out of the guy, completely ignore the facts and hard data, make repeated baseless and nonsensical claims/statements (NO, you cannot accelerate to the point just shy of terminal understeer with MDM on, and NO MDM does not grind on the rear wheels) and ultimately admit (which anyone reading this thread deduced in 10 seconds) you have no idea what you are talking about. Then, after he finally expresses his complete and total frustration now you want to be friends????

Do you even track bro?
I just want to say again, I'm sorry I upset Dogbone. I really wasn't trying to give anybody a hard time, or troll.

Yes sir, I do track three different BMWs covering model years 1979 to 2013, but I only have about 80 track days under my belt so far.

If you ever want to track on the east coast, let me know, we do a couple open practice days a month with full flagger and EMT support at Summit Main.
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      05-15-2018, 07:00 PM   #104
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Quote:
Originally Posted by rhyary View Post
The TrackAddict Brake indicator is calculated and very inaccurate. I think the throttle is more accurate. It is not Aim DL by any mean.

I am taking tire temps to see the distribution of heat across the the 275 to verify camber. especially on the passenger front. regardless of the correct temp, do you think the tire surface cool in significantly different between the inside and outside?

All the comments about my driving are accurate and I am working on it. I am slowing too much into the corners. I am practicing by running higher gears so I can hit the gas and not worry about spinning out. I hit turn 18 multiple time at 48mph and there is no reason to take it below 50mph. Last year I was at 43-45 range. Same at turn 1, i am trail braking into it but too much. I trail brake into every corner. some just to establish habit, some for real.

I mainly practice now getting rid of cruising between off the brakes and on the gas. It is better then last year, but far far from perfect. I watched many YouTube videos in the winter that shows driver feet work.

I am not sure if this is a right approach but I take many laps mostly on 5th gear. That allows me to concentrate on entry speed and timing of brakes and gas. it turns the car into a Miata so no lap records.
What you need to is a consistent car and your driving will get better much faster. Otherwise, you're constantly adjusting your driving as the car is behaving differently.

Experience has told me you can really only focus on and improve one small aspect of your driving per session.
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      05-15-2018, 08:03 PM   #105
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Quote:
Originally Posted by dparm View Post
You want something like this which ties into an existing datalogger and actually reads tire temps across the entire width of the tire in real-time:

http://izzeracing.com/products/tire-...m-systems.html


Overlaying the temperature graphs with the other AIM data can really help you see the relationship between tire stress and a given corner. It's truly amazing.

that is pretty incredible, thanks for sharing. it really illustrates and reaffirms (in my opinion) the almost uselessness of a tire pyrometer. the real time tread temps fluctuate quite a bit.
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      05-16-2018, 05:34 AM   #106
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What you need to is a consistent car and your driving will get better much faster. Otherwise, you're constantly adjusting your driving as the car is behaving differently.

Experience has told me you can really only focus on and improve one small aspect of your driving per session.
Thank you for your sound advice.

Consistence car is not my objective this year. This year my objective is to try as many settings as I can and see if my butt can tell the difference. I can tell that changing the sway bar was a good thing. Perhaps I will even go to the softest settings on the front sway bar later this summer.

Per JRZ clarification, the shaft compression tune the grip, that helps as this is what I am after. It helps because I am going to keep the HS and rebound constant and focus on the shaft (Front and Back). I am happy with the rebound for now.

For now, I also gave up trying to beat my 1:37.x from last year. It sounds that you are all collectively agree the best lap time comes from a better driver and I am totally agree with the collective wisdom.

At a pace of 1:40-1:43 I can push the car enough to be safe and learn the suspension.

I also gave up winning my HPDE days as I can see plenty of cars that are faster then mine. Oh well, there goes the dream.
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      05-16-2018, 09:27 AM   #107
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that is pretty incredible, thanks for sharing. it really illustrates and reaffirms (in my opinion) the almost uselessness of a tire pyrometer. the real time tread temps fluctuate quite a bit.

Yeah, I saw this in a seminar with the inputs into RaceStudio. Crazy seeing it overlaid with the track map and suspension rebound and everything. They were talking about using it to understand how to tune the camber and other suspension settings for a given track.
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      05-16-2018, 03:34 PM   #108
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OP you should buy Ross Bentleys Speed Secrets ebook called shocks for drivers. It's like 3 bucks and covers a bunch of these topics
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      05-19-2018, 05:23 PM   #109
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i highly suggest you email ross bentley (speedsecrets.com) and ask him for access to the recent "tune your car's handling" webinar. you won't be able to ask questions (it was live), but the six hours of content is well worth it.
I just ordered the Ultimate.
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      05-19-2018, 05:55 PM   #110
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He has a weekly podcast that is quite good as well. I'm more of an auditory learner and I like to listen several times, so that is what appeals the most to me. Th book is great though.
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