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John's not so cheap thrills, 90 1.6 with subaru td04

Old Yesterday | 02:45 PM
  #201  
curly's Avatar
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Hand position alone isn't the root of the problem. While yes, you should be around 9:00 and 3:00, the bigger problem is how much you HAVE to turn the wheel. It may be a track thing, it may be a car thing, it may be a tire thing, or it may be a driver thing.

I'll give you an example: Years ago I did a track day and was constantly shifting at 5000rpm. Couldn't tell you why. A few months later I was on the dyno and made a disappointing 150hp, and it fell on it's face above 5000. Ended up buying an Artech 3" exhaust, re-dyno'd, and made close to 200 a little above 6000 without any other changes. My point is I intuitively found the best shift points by feeling the power band, and I believe that's what you're doing with your hands.

Look into your sway settings, shock settings, tire pressures throughout the day, alignment, rake, diff, etc etc. My guess is you've got a lot of understeer dialed into one of those things, and it's really hurting you, at least at that track. Do you have another video from another track that maybe you can compare to?

Finally, in a fully caged car, I would suggest at least some gloves, always long pants, and a Hans, can't tell if you're wearing one in that video. From your footwell photos, I'd also ditch all plastic trim pieces, and since the dash is pulled, remove all the firewall insulation. Refer to roda's photos, there's nothing there except metal, which doesn't melt and burn you as easy as plastic.
Old Yesterday | 03:33 PM
  #202  
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You're a Saint, Curly. Another cat for sure! Your analogy makes perfect sense, and now I've got something to work with at least - figure out what's causing the understeer that both you and Fireindc mentioned. I can have Jeff and his crew help with that part. I think. I make videos of pretty much every session so I can do some comparisons as well.

Funny you should mention the plastics - I was looking at Roda's pictures and going, "Huh, I should pull that stuff out of my car too now that the car is home." Even more reasons to keep it for a bit before sending it off to Jeff's for repairs/adjustments/heatproofing.

Regarding clothing, I always make a point of wearing 100% cotton shirts, long pants, and underwear, with a leather belt and 100% wool socks and SFI rated shoes when I'm on the track. If I'm in the Miata (which has a harness) then I was using a Zamp 2A HANS https://www.zamp-racing.com/series2A until last weekend when I finally caved and upgraded to one of the new (to me) Simpson Hybrids https://www.simpsonraceproducts.com/...s/HSLRG11PAFIA
On cold days I add an inner layer of CarbonX or Traqgear undergarments.
I actually own two (rather old) complete firesuits - a Simpson and a G-Force Pro - but it has never, ever been cold enough that I've been willing to wear them. Heat Exhaustion is A Definite. Having my street car burst into flames, not so much (although I have been taking the above preventative measures regardless.) I've had a set of Simpson gloves rattling around my helmet bag for at least a year, but given my 'druthers I prefer bare hands on the steering wheel so I can better feel what's going on with the car. I had pretty much resigned myself to wearing them moving forward though, since I literally got a blister on the palm of my right hand from fighting with the shifter last weekend. (And I can't touch the transmission tunnel with bare skin after a run, and hand protection is pretty much always a good idea, etc, etc.)
Old Yesterday | 05:08 PM
  #203  
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Originally Posted by curly
...Do you have another video from another track that maybe you can compare to?...
Here's a video I've shared previously, actually - same car, probably the same tires, back in December on the Radford (formerly the Bondurant) track. If you think I was twisting my hands around a lot on Firebird West, you're going to just love this one. There's an even more extreme example after the 2-off.


If I'm interpreting this correctly this means it wasn't the track.

Tires: I've been aiming for about 27psi hot for the Contis - the pyrometer seems to show temps in the middle and outer edges that are at least within the ballpark of each other; Inner edges have been showing hotter on all four tires. Admittedly that's probably a few minutes after the car is back in the pits though - I don't have an opportunity to take a pyrometer to the tires any earlier.

Alignment: I've had the shop aiming for the vicinity of what the previous owner used because I have no idea what I'm doing:
Example 1
Example 1

Example 2
Example 2
Old Yesterday | 05:27 PM
  #204  
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IMO when you go off in that video it looks like you're at the limit of the tires grip which is when it starts understeering and instead of backing off the throttle you just add more steering lock and the car continues to plow forward.

My guess is that you're simply misjudging how much steering you need, especially in the video from last weekend. I believe you mentioned the tires were squealing a ton from the fresh pavement, but it seems to me like it might just be from using way too much steering angle.

*Obligatory I don't claim to be an excellent driver or analyst
Old Yesterday | 07:04 PM
  #205  
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Originally Posted by SimBa
IMO when you go off in that video it looks like you're at the limit of the tires grip which is when it starts understeering and instead of backing off the throttle you just add more steering lock and the car continues to plow forward.
This... in too hot, and instead of slowing you're just inputting more steering lock and plowing around. The Radford clip is what happens when you push this too far. I don't have any video from West, but looked a couple of spec Miata onboards, and there are a couple of turns at West where they're reaching as much as 180* of steering angle, but only briefly before unwinding past the apex. You're going past 180* and holding it there as the car plows... Hands at 9 and 3 and slow down your inputs.
Old Yesterday | 07:12 PM
  #206  
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Originally Posted by SimBa
...it might just be from using way too much steering angle.

*Obligatory I don't claim to be an excellent driver or analyst
Thanks for taking a stab at the situation SimBa! You've really helped me understand what/why folks are saying what they are.
I think this is why Curly was unleashing expletives about the lack of spinning or even oversteer. Based on what he was saying, my impression is that on a properly set-up car if you crank the wheel too far over then the back end is coming around. The fact that I can turn the wheel that much, that fast, and the car just howls and plows means there's something impressively jacked about the car's setup.
At least I think that's what is being said. Honestly l just drive the thing. This mechanical stuff is very clearly not something I'm good at, but I'm trying to improve.
Old Yesterday | 07:36 PM
  #207  
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It took me a while to realize that if I turn the steering wheel more and the car doesn't turn more, it means the front tires are overloaded and I'm going to fast, regardless of how much speed I feel that the car should be able to carry.

If the car's setup is more prone to understeer, like yours looks to be, then the rear isn't going to come around, the car will simply plow forward. Once your past the limit of the tires' grip then no amount of additional steering lock is going to help. Similar to what happens if you lock the brakes up.

At that point you'd want to unwind the steering a bit to let the tires regain grip and slow the car down (gently lifting off the throttle and/or moving onto the brakes) to put more of the cars weight into the front tires, which should help with grip some. Just make sure not to be too quick on that transition because then the weight transfer will cause the rear to pendulum around.

That's my somewhat rushed assessment. I really like playing rally sim's for this kind of stuff because you're usually having to use the brakes and gas to pitch and balance the weight of the car.
Old Yesterday | 09:38 PM
  #208  
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It's not that you should spin if you turn too much, but you're able to mash the gas, with 180* of wheel, and zero complaints from the rear.

You're for sure over driving the car, but IMO (amateur opinion), some of your driving should induce a bit of oversteer.

Alignment looks fine, what are you ride heights? Diff? Sway bars and settings? Hot tire pressures?
Old Today | 03:44 AM
  #209  
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I'd suggest you put an experienced fast driver in the car, and get a diagnosis and suggestions from them. Get some priorities sorted, and you can do the important stuff first, and chip away at the rest.
Old Today | 01:20 PM
  #210  
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Originally Posted by Gee Emm
I'd suggest you put an experienced fast driver in the car, and get a diagnosis and suggestions from them. Get some priorities sorted, and you can do the important stuff first, and chip away at the rest.
Wise words, Gee Emm - I'm working from a prioritized list currently -
1) Prepping the car to paint the cage (probably just going to do rustoleum semi-gloss clear - has the advantage of not hiding any issues with the cage if something develops.)
2) Adding/sealing ductwork to try to get those engine temps down
3) Handing the car to Jeff to do more heat abatement for the cockpit (heat shield in the transmission tunnel) and fix a few mechanical items. If they can figure out a clever way to add that footwell intrusion brace in then that will happen too.

All of the handling/setup stuff is being added to the list but isn't at the top - I need to keep from melting stuff first, and I can't even put the car back together fully until the cage is rustproofed somehow.

I really do like the suggestion of having an experienced fast driver take it out and make suggestions - I'll see if I can make that happen next month!
Old Today | 04:36 PM
  #211  
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Since I have a few minutes between tasks here are a few comparison screenshots I grabbed. On the left are shots of the maximum wheel position for a few corners during the very first session of the weekend. The track was stone cold because we were the very first group out. Same goes for my tires. I had never driven the track before (even in simulator because no one has modeled it yet) so the early lap this was taken from was about 20 seconds slower than my best time for the weekend, and this is a 1.1 mile track! There was no pushing. Heck, one of my friends from the track said I took so long to go around he thought I pulled off or got lost.
The pictures on the right are from my fastest lap of the weekend, aka the video with all the screeching a few posts ago. (Not the one where I kept falling off of the track - that was a different track and I was under the influence of Rich.)
I grabbed screenshots of what appeared to be the greatest degree of rotation for the steering wheel (excluding twitches) for each corner. Yes the apex changed and so the screenshot locations differ somewhat, but the intent was to capture how much I needed to turn the wheel to get the car around the corner. I think I did an acceptable job of that in these shots.
So let's see what we've got:
Picture 1: The track map for reference
I'm the map!
I'm the map!

Corner 1: a gentle left turn that I can take full-out as I discovered by the time the video was taken.
A bit more turn-in but pretty close
A bit more turn-in but pretty close

Corner 12 - a U-turn onto what I refer to as "The Octopus"
What, maybe a 15' difference?
What, maybe a 15' difference?

Corner 7 - another relatively sharp corner exiting the Octopus
Eh, a few degrees more
Eh, a few degrees more

Corner 5 - entering the main straight
Whoa, Doggie!  Break out the seedlings Martha because we're plowing a field!
Whoa, Doggie! Break out the seedlings Martha because we're plowing a field!

Corner 4 - an extremely sharp turn at the end of the main straight
Martha!  Git yerself more seedlings!
Martha! Git yerself more seedlings!

Bonus shot: Note the front tires are not completely sideways, contrary to what they sound like in the video.
At least everything is pointed in the correct direction
At least everything is pointed in the correct direction

In summary, it appears that (with the exception of when I was obviously overdriving the car immediately before and after the main straight) with the way the car is set up currently I really do need to turn the wheel that much to traverse the corners on this track.
Old Today | 07:35 PM
  #212  
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FFS, lose that wing! Leave the aero until you have sorted the car and the driver.

A big wing, that far out the back is a surefire recipe for terminal understeer. NOBODY who has seen that car, and not given advice along these lines is be trusted again. Ever.
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