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Silly me: I bought a 944 for E-street Autocross

Old 05-15-2017, 10:50 AM
  #76  
edfishjr
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M030 struts going in. You can see the blue/white dot spring, which has 2 diameter transitions, both coil diameter and wire diameter change. A bit of the Tarret front sway bar is also visible.

For now, that's the stock bump stop.
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Old 05-15-2017, 11:33 AM
  #77  
burglar
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Wow wire diameter change? That sounds really expensive, is that common in the OEM?
Old 05-15-2017, 01:43 PM
  #78  
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Originally Posted by burglar
Wow wire diameter change? That sounds really expensive, is that common in the OEM?
According to Carroll Smith in Tune To Win, Porsche was the first to do it for racing.

Machine the dia. change first, then coil it.

I have no idea how common it is. That's why I had to find those specific springs to be legal.

The wire gets thinner at the top and larger coil diameter, both making the upper part softer. It also allows the standard upper perch to be used.
Old 05-16-2017, 12:49 PM
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New, M030 "green dot" front control arm caster mount vs. stock.

More rubber, not less! and a different, much cheaper, design. The stock has cut-outs in the rubber that would seem to allow more flex.

Update: I'm pretty sure that what was on there was not "stock", but the later 968 design that had much less rubber.
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Old 05-19-2017, 12:10 AM
  #80  
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This is what it looks like with the M030 front struts set as low as they will go.
Definitely some rake now, when it had become close to flat once I put all the camber in.

The front Konis are set in the middle (bump and rebound), borrowed Bilstein HD rears have more low-speed damping in both directions than stock and more than Koni Sport in bump (issues with the JRZs not all worked out yet) got the Tarrett front bar and the M030 20mm rear bar. Car is definitely stiffer.

Tomorrow I will raise the front a bit, probably about 1/4", just to be safe, and autocross it Sunday. Supposed to rain/storm, so I imagine I'll move the struts to full soft.

I've got the torsion bars for the rear in hand, now. I need to find the best possible write-up of how to index new bars to try to get it right the first time.
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Old 05-19-2017, 10:04 AM
  #81  
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Originally Posted by edfishjr
I've got the torsion bars for the rear in hand, now. I need to find the best possible write-up of how to index new bars to try to get it right the first time.
Not sure how the 944 rear works, but on the 911 I put an angle gauge (phone app actually) on the spring plate. There used to be a calculator tool that told you the angle for the desired height but it seems to have been lost to the ages. If you measure the angle the old ones produce you can probably guess pretty darn close with the new bars. At least you can get them equal height easily this way. How much stiffer are the M030 bars?

Also don't know if it's useful, but the 245-15 Rival S is now in stock at TR. Mine showed up yesterday.
Old 05-19-2017, 03:25 PM
  #82  
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Originally Posted by burglar
Not sure how the 944 rear works, but on the 911 I put an angle gauge... How much stiffer are the M030 bars?
I think 911/944 are pretty similar.

The 25.5 bar should be 38.6% stiffer than the 23.5
Old 05-20-2017, 12:02 PM
  #83  
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Tiny Rivals team member #2.
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Old 05-20-2017, 12:09 PM
  #84  
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Originally Posted by burglar
Tiny Rivals team member #2.
Do you have the 225's in front? I have a worn set of previous gen Rivals that are all 225's. I too have been waiting for the 245's for my 7&8x15 Fuchs. They are SHORT! Any impressions on performance yet?
Old 05-20-2017, 05:37 PM
  #85  
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225/245 on 15x7/15x9. Running them tomorrow, but on a crappy lot & it's supposed to rain.

So far, on concrete at least, other testing seems to be showing they're very similar or even slightly better speed wise to the RE71r, but much more tolerant of overdriving.
Old 05-20-2017, 07:56 PM
  #86  
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Originally Posted by burglar
Tiny Rivals team member #2.
Cool!

I have a friend who keeps commenting on how small my wheels look.
Old 05-26-2017, 01:32 PM
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Once you get the new tbars in you'll be able to get the whole car really low if you want to. Mine was pretty slammed (see my profile pic for reference)

Saw you're registered for Bristol; I'm registered in AS right now but I'm awful tempted to buy a plane ticket and try to bum a codrive with you instead of towing it all the way up there!
Old 05-26-2017, 04:29 PM
  #88  
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Originally Posted by knfeparty
Once you get the new tbars in you'll be able to get the whole car really low if you want to. Mine was pretty slammed (see my profile pic for reference)

Saw you're registered for Bristol; I'm registered in AS right now but I'm awful tempted to buy a plane ticket and try to bum a codrive with you instead of towing it all the way up there!
I've already offered my seat to someone else. Not sure if he registered, however...
Old 05-27-2017, 07:50 PM
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This shifting to 3rd is difficult! (Actually, it's the downshift back to 2nd that's tricky.)

Last weekend I beat one of the Miatas that beat me previously, but still lost to the brothers in the '99 Sport. But, I was closer. And data shows that on my fast run I made a mistake that I hadn't made previously that might have cost me the win.

For this last race I had both sway bars in, the M030 front springs and Koni struts, a set of borrowed Bilstein HDs for the rear, and stock torsion bars. You'd think this would be awful, but it was better than previously. I didn't have the front sway too stiff.

A front wheel bearing got noisy. Installing new ones now.

Next week I tackle the torsion bar swap.

And I am seriously researching bumpstops and bumpstop tuning techniques. The JRZ's (still a work in progress) have to have serious bumpstops that limit the travel to keep from self-destructing, so I'm doing the bumpstop thing sooner rather than later.
Old 06-05-2017, 12:34 AM
  #90  
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I finally won ES in my local region today, driving the 944 and beating both of the brothers in the '99 Sport Miata for the first time.

One or the other brother had taken the win in each of the first 3 events and 3rd was the best I'd done to date.

2 reasons stand out:

1) Yesterday we put on an advanced autocross driving school, headed up by Steve Brollier. (Steve has 4 Solo championships and 9 Pro-Solo.) The brothers were students in the school, while I was an instructor. The funny thing is, I think I got more out of it than they did, even though I didn't really get to practice the drills, just ride with the students and give feedback. This morning I was able to walk the course 3 times, develop a good driving plan, and put the lessons to work. (I didn't instruct the brothers. We joked about how it would be a conflict of interest!)

2) The car has been uncomfortably loose, so I got up early this morning and measured the rear toe. It was slightly toe-out. When last checked it was slightly toe-in. After all the disassembling and assembling I've done lately, this wasn't too surprising. I dialed in some negative toe and the car was much more stable. With the Tarret front sway bar set to full stiff the car is rolling a lot less and I was able to lower the rear tire pressures. Grip was increased and, for the very first time, the chassis could take all the grip that the tires were delivering without immediately going bonkers.

Still a lot more work to do and some key parts to install, but the car (and the driver) are getting faster. Lack of damping in the rear borrowed Bilsteins is causing the back end to actually start hopping up and down during max cornering at the location of highest grip on our site. (Where there's no sealant.) The JRZs + M030 torsion bars should fix that.

Last edited by edfishjr; 06-05-2017 at 12:22 PM.

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