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      04-30-2018, 11:53 AM   #23
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>> 40mph in a 400+ hp
650hp (at least advertised)

good point about seeing hands. i don't know where to mount the camera. will do if i can

in have telemetries but did not impose on the video.

next track days are May 11,12 and 13.
i will take everything into consideration and report back.

decided to go full soft on SB to get datapoints.

i am not trying to win a race, so making one change at a time is fine by me

Someone already advised about not trying to win HPDE days :-)
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      04-30-2018, 12:00 PM   #24
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Quote:
Originally Posted by rhyary View Post
>> 40mph in a 400+ hp
650hp (at least advertised)

good point about seeing hands. i don't know where to mount the camera. will do if i can

in have telemetries but did not impose on the video.

next track days are May 11,12 and 13.
i will take everything into consideration and report back.

decided to go full soft on SB to get datapoints.

i am not trying to win a race, so making one change at a time is fine by me

Someone already advised about not trying to win HPDE days :-)


Mount the camera with the headrest posts. I used to do this with the Tackform mount since it would let you see the windshield, your hands, and the steering wheel quite easily with a GoPro. The headrest posts also dampen a lot of vibration so the video quality will remain smooth.

The reason I asked about telemetry is because you could, in theory, use something like an AIM Solo or similar device to calculate the amount of understeer (via a math-channel) and quantifiably show how much you are removing with the sway bar and tire adjustments.
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      04-30-2018, 12:13 PM   #25
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I have what RaceAddict recommend.
Dual GPS (10Ghz) and OBDLink WiFi using iPhone.

I no longer have headrest posts.
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      04-30-2018, 12:40 PM   #26
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Quote:
Originally Posted by rhyary View Post
first, I got the springs mixed up,
so 750 front 900 rear.

The car does not feel stiff.
Rear is non coil over. JRZ recommended staying like the stock config.

I have the JRZ 14-52 (4-way)

JRZ made the spring recommendations based on informations I gave them for my objectives. It is not my daily driver, but it is comfortable on the street when I dial everything to soft after track day.

Weight is with 165 driver and half tank.

Tires are currently Yoko ADO8R

I will dial back the sway bars. they are still set to when I had the stock ZCP.
4-way, huh? That's quite a formidable suspension. On an enthusiast forum such as this one, I would say you will find very few people that can give you firsthand/expert suspension tuning advice on a 4-way suspension. The price tag alone limits the number of people that will have any experience with that kind of thing.

I've personally watched a race technician, who also is a pro driver, tune a JRZ 3-way suspension at Buttonwillow. My friend hired him to show up at the track, drive the car and tune the setup. This pro driver is currently sponsored, actively races and gets tv time. He is a test driver of race slicks for Pirelli. And he is a full race mechanic. He travels with race teams and provides tech support. When I tell you that this guy knows his stuff, I do not say that lightly. It took him several sessions on track and two hours to get the suspension dialed in. And when he was done, the car felt quite different (better) to my friend. I'm saying this because if you invested $14k into a 4-way suspension, I would REALLY recommend you find a pro like that and do the same. It will be money well spent. Anything short of that, and you are not using your investment to the fullest. In fact, with all those adjustment possibilities, it's more than likely that the setup is wrong and it's holding you back.

But regardless of the suspension, given the AD08 tires you run, my personal feeling/opinion (based on my experiences) is that the 750 is still too high on the front. (I know others will argue with me.) Let's put it this way----I have a supercharger in the nose of the car that adds around 100 lbs up there that I don't think you have, I have full aero on the car including splitter, 67" wing, canards, hood vents and even cutting holes in the fenders, I run full 305-square Pirelli slicks on the car, and our cars weigh basically the same. Due to these factors, I would argue I demand more out of my front end than you do at the moment----I'm weighing it down more, I'm pressing on it harder with aero and gripping more than you. Even with all this, I'm using 600 lbs springs in the front. When I tried 750 lbs in the front, I could not make the car stick. We talked about this on my build thread. (Starting with Post #417: http://www.m3post.com/forums/showthr...ht=750&page=19 ) (And I believe most people would say that my car sticks to the ground pretty good.)

Anyway, if you are going to put the highest-end equipment available on your car, I respect that and I think it's great. But I think you need to make the full commitment and get some seriously pro help to dial it all in. This is beyond a sway bar setting. If a seasoned pro takes hours to dial a 3-way in, then any hobbyist who goes to the track once a month, will spend years sorting out a 4-way, if they ever even do it at all.

And we haven't even begun to delve into how alignment affects all this.....
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      04-30-2018, 01:20 PM   #27
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750/900 does seem like a pushy setup, especially for staggered tires (and wheels?).

What is your front camber at? You could try more depending on how you are working the tire.

It sounds like you want to soften both front and rear bare. You only need to soften the front bar if you want to see how it handles with more rear bias. Soften both might net zero, or make things worse.

Keep in mind, soften the front bar will make it more difficult to put down power on exit.

I agree with others, driving line and technique may help, and possibly other suspension changes too.
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      04-30-2018, 03:52 PM   #28
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>> I have a supercharger in the nose of the car that adds around 100 lbs up there that I don't think you have...

But I do.

>> ...I respect that and I think it's great. But I think you need to make the full commitment and get some seriously pro help to dial it all in.

I am happy to get input from you and other form members. You guys are pros enough for my needs.

I plan to maximize every bit of equipment i bought. The only difference between me and a race driver is that I have patience and I can take all summer long to perfect the system one click at a time. In fact I don't mind taking few summers to do it. I DON'T have to win anything this weekend or any other weekend.

I enjoy trying and experimenting and changing. So the more ways, the merrier . And while i may go slower or faster, I assure you I enjoy every minute I spend on the track.

I enjoy the input from you, anyone and everyone and I hope to share my experiences, if I have something to share.

There is no point talking about money on public forms. So let's talk about technical, opinions and feelings and keep money out of it. How much things cost is public information. But what it means to each individual is not the same and I consider this a private matter.

Make sense?
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      04-30-2018, 03:58 PM   #29
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Quote:
Originally Posted by rhyary View Post
Here is the link to a hot lap.
When you hear the tires, I need more traction.
After one lap I am catching up to Nismo GTR before turn 3.
As soon as we finish righthand turn 3 notice how the GTR takes off and establish a serious gap between turn 3 and 4. I then catch him again at turn 6 and he give me a point by after wheelly hill. What a nice driver.

Turn 1 and 2 are off camber. From your video you're turning early at the flag, entry speed is carrying your right front onto the crest. Turn later on 1, Apex 2 is the one you should be shooting to hit.

Remember its a motorcycle track, some turns are designed with 2 wheels in mind.
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      04-30-2018, 04:05 PM   #30
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>> 750/900 does seem like a pushy setup.

correct, and it is pushy on purpose.

What is your front camber at?
-2.5 and I can push it in a bit more. I may just do that to see what happens

My tire temp were the same on the onside and the inside of the front tires with aaaalmost the same wear. a bit more on the outside.

the tire center as about 20-30 degrees colder
170-130-160 degrees outside to inside.

Hot 38psi. I am going to try 36psi hot.

because of the temp, i don't want to change the camber yet.

as a data point, coming down from 131 to 41 mph feels great, including trail braking into the apex. so don't want to change alignment yet.
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      04-30-2018, 04:11 PM   #31
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>> Turn 1 and 2 are off camber.
Correct if you turn late. I am turning in before the off camber. If i go further, I am in much worse off camber

yes.... the apex becomes the second carb. I tried that and it was not better.
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      04-30-2018, 04:54 PM   #32
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My thoughts are that you simply need to tweak all the variable for more front end grip. When I went through that process I maxed out front camber (about -3.8 is all I could get) and went to a square setup with bigger, stickier tires. Finally, I added a rear wing and massive front splitter. Now my turn in is great and on fast rounders I get a little pushy if I'm really on it. But, that's to be expected since I'm essentially at full weight.
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      04-30-2018, 06:01 PM   #33
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>> When I went through that process

did you enjoy the process?

I do. I am learning a lot as I do one thing at a time.

once I finish the SB thread here, I will open another thread about the next thing.

I hope they won't run out of Internet before I finish posting all my questions
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      04-30-2018, 06:21 PM   #34
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Do you have any plans to run WGI?
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      04-30-2018, 06:28 PM   #35
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Quote:
Originally Posted by rhyary View Post
>> When I went through that process

did you enjoy the process?
As my track buddies will confirm, I'm pretty impatient when it comes to results. I want to go as fast as my tolerance will allow (which is sometimes greater than my driving skills). I don't need to feel every little change along the way. I simply hate understeer (or anything else that holds me back for that matter).
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      04-30-2018, 07:31 PM   #36
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Quote:
Originally Posted by ThunderMoose View Post
Do you have any plans to run WGI?
Yes. I don't know when.
I rather sort out my suspension at NYST first.
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      05-01-2018, 07:04 AM   #37
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Sometimes it's just the track feature? The car can't be perfect everywhere on any track, so rather than tweaking the setup significantly for this one track and compound turns, I would opt for adapting my approach and like Rich said get on that outside rear tire. In other words, my fear in attempting to "solve" this one issue I have might (likely) result in now introducing issues elsewhere I'm not interested in having (like mid-corner in a 100mph sweeper being loose).

Rich's description reminded me of driving an E36 M3 Euro track/race car about 10 years ago at VIR South course. The turn into the infield section off the main back straight is called "the bitch" for good reason. I used a semi-double apex routine on that corner, trail-braking very hard into it, turning in and then you get mid corner on maintenance throttle and the car wants to push more while at the same time from there to track out the track drops away off camber - fun. In that mid corner push area, I would left foot brake a nice smooth push with a smooth throttle lift coupled with a slight opening on the wheel to rotate the car just enough to get into my 2nd apex and then smoothly roll on the beans out of that modified S50B32. The car responded perfectly resulting just the right amount of slight yaw under full power through track out. What initially felt awful in that car turned into the most fun corner each time the whole weekend.

This particular car had been setup by a high level pro driver, so I guess I had the bias that any issue with it was my fault, lol...and it was.

Anyway, my first choice would be to work on my approach on sections as described, but with your experience you likely have already been doing that. Perhaps brainstorm more options or better yet have someone else you trust to drive to the car without giving them any bias up front.
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      05-01-2018, 02:05 PM   #38
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>> The car can't be perfect everywhere on any track, so rather than tweaking the setup significantly for this one track and compound turns.

My approach is first to learn my suspension, not learn the track. So I keep the track constant and make changes to learn the effect of every suspension change.

Should I bother asking about my 3mm spacers or do you guys need a break?
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      05-01-2018, 02:06 PM   #39
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Improving 40mph turns

>> The car can't be perfect everywhere on any track, so rather than tweaking the setup significantly for this one track and compound turns.

My approach is first to learn my suspension, not learn the track. So I keep the track constant and make changes to learn the effect of every suspension change.

Should I bother asking about my 3mm spacers or do you guys need a break?
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      05-01-2018, 02:15 PM   #40
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Quote:
Originally Posted by rhyary View Post
>> The car can't be perfect everywhere on any track, so rather than tweaking the setup significantly for this one track and compound turns.

My approach is first to learn my suspension, not learn the track. So I keep the track constant and make changes to learn the effect of every suspension change.

Should I bother asking about my 3mm spacers or do you guys need a break?

I think what the other poster meant was that you can't tune the suspension to be ideally setup for every single corner on a given course. It's always going to be a compromise.
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      05-01-2018, 02:47 PM   #41
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>> It's always going to be a compromise.

it is what I love about it. It is never get boring. Even if you stay on only one track.
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      05-01-2018, 02:48 PM   #42
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When were those temps taken and by whom and how long after a hot lap? Those are rookie numbers you need to pump those numbers up (or you’ve taken them after a cooldown lap). Somethjng is weird with the center that cold.
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      05-01-2018, 03:08 PM   #43
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Quote:
Originally Posted by rhyary View Post
>> Turn 1 and 2 are off camber.
Correct if you turn late. I am turning in before the off camber. If i go further, I am in much worse off camber

yes.... the apex becomes the second carb. I tried that and it was not better.
I've been on NYST many times and tried both methods. It just changes angle of attack.
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      05-01-2018, 03:12 PM   #44
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I can't tell without throttle input displayed, but you're a little stabby with the throttle in mid-corner. You're off throttle, then test the waters with a stab and then lift really quick. 3 quick movements pushing the car further off your line. (As pictured earlier) On longer turns you need to find the throttle input that equals the amount of grip available and stay with it. If it's not fast enough gently apply throttle. You're still a bit too egger, your fun is out weighing your fast. Also, you're trying to flow, rather than approach each turn uniquely. Ideally, you want to maximize the track so you're accelerating/braking in as straight of a line as possible while finding the smallest apex for each turn.

This video does a great job simplifying driving lines and WHY they are what they are.
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