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SCCA National Champtionships- The RunOffs in Sonoma 2018 - Countdown

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SCCA National Champtionships- The RunOffs in Sonoma 2018 - Countdown

 
Old 10-11-2018, 01:30 AM
  #61  
dr bob
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If you aren't going to shorten the rod or raise the top mount, you'll need to install a taller bump stop rather than shorter. To protect the shock from bottoming and blowing the seals. Or raise the ride height so the shock is protected, or raise the spring rate so the shock is protected. Your goal, as I shared above, is to avoid hitting the bump stops and avoid bottoming the shock.
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Old 10-11-2018, 12:03 PM
  #62  
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Originally Posted by dr bob View Post
If you aren't going to shorten the rod or raise the top mount, you'll need to install a taller bump stop rather than shorter. To protect the shock from bottoming and blowing the seals. Or raise the ride height so the shock is protected, or raise the spring rate so the shock is protected. Your goal, as I shared above, is to avoid hitting the bump stops and avoid bottoming the shock.
I was talking to the koni repair folks about why this is a problem. they didnt seem like they were convinced that the shock body was contacted with enough force to do damage. there are some pretty tall bump stops now, and prior, for the life of the shocks , there was this litttle bumpstop that was made of a light foam that i dont think it did anything but cushion direct contact.

what about cutting that big rubber bushing in half? wouldnt that solve the issue? that way, i would get near 2" more travel as long as the adjusters could make up the difference.

dont know if i can do much other than raise the ride height a bit, especially since there is one part of the track that crushes the outside wheel and suspension. however, stiffening the sway bar will do that same thing too. (there is no where near any spots on the track , or any track for that matter where compression is tested enough to get the shock to bottom out. i have hours of fender-cam to show this. its all on the high speed , compression curves so swaybar changes could fix this.
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Old 10-11-2018, 01:13 PM
  #63  
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UGGGG just spoke to Performance Shock Inc at Sonoma Raceway........turns out the shock is fine... i was the way i was compressing it. since it is not gas, but only oil, when i was compressing it on its side, the oil doensnt flow properly and makes it feel like the shock is dead. turns out, they put it on the shock dyno and everything is fine at all settings. so, they will hog out that perch for the bump stop to fit and that will give me a few " more travel before it hits the bump stop. well, got the bump stop issue fixed, and the shock on its way back to me today . On the road Monday to the largest race in the world!

still a weird characteristic....... that means you cant use koni shocks on high banking?
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Old 10-11-2018, 01:46 PM
  #64  
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that means you cant use Koni shocks on high banking?
No, not at all. The banking converts what would have been inertial forces throwing you off the track into "gravitational" forces, more down than out. Your motor oil will stay in the sump at speed, and your trans fluid, and your shock fluid.
NOTE: if you slow down on the track (yellow flag) get down on or near the apron... staying on the high bank at low speeds can move all your motor oil away from the pickup.

BTW, how banked is that track? I apologize if you already mentioned it and I missed it. Daytona was 37 degrees, and very hard to walk on. A hoot to drive on at speeds!
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Old 10-11-2018, 01:57 PM
  #65  
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that was a little tongue and cheek. it just seems weird that the shock wouldnt work on compression on its side. i guess if you have to slow way down on the banking, you might not have much suspension, or if you are a using downforce to drive on the side of a tunnel, you might have a problem.

i dont know what the banking was at California speedway, but it seemed pretty steep. (probably not as much as daytona) however, there is no real banking at sears, but some long high speed turns (carousel)

lets see what we have when the shock is back on the car tomorrow and ready to go racing!

mk

Originally Posted by Carl Fausett View Post
No, not at all. The banking converts what would have been inertial forces throwing you off the track into "gravitational" forces, more down than out. Your motor oil will stay in the sump at speed, and your trans fluid, and your shock fluid.
NOTE: if you slow down on the track (yellow flag) get down on or near the apron... staying on the high bank at low speeds can move all your motor oil away from the pickup.

BTW, how banked is that track? I apologize if you already mentioned it and I missed it. Daytona was 37 degrees, and very hard to walk on. A hoot to drive on at speeds!
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Old 10-12-2018, 07:58 PM
  #66  
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I found a way to stiffen up the 928 suspension..



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Old 10-12-2018, 10:35 PM
  #67  
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Originally Posted by mark kibort View Post
I found a way to stiffen up the 928 suspension..
This is extra funny thinking about certain people who will not realize you are kidding.
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Old 10-13-2018, 01:34 AM
  #68  
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Originally Posted by Hacker-Pschorr View Post
This is extra funny thinking about certain people who will not realize you are kidding.
hahahhaaa

I asked the koni repair guy if he had ever heard of this before, he said no.... seems natural..... i said, "what the heck do you use to roll the car around when the shocks are removed? i just worried that the 800lbs would crush the Scandinavian bookcase wood . it gives it the ride that Harley, "HardTail " feel.

What was the last joke picture i posted where a few thought i was serous?
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Old 10-13-2018, 03:30 AM
  #69  
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I wooden use that. Knot on the track anyway. Just goes against my grain.
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Old 10-13-2018, 01:28 PM
  #70  
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Originally Posted by dr bob View Post
I wooden use that. Knot on the track anyway. Just goes against my grain.
But, you wood use it to roll the car in to the garage.
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Old 10-13-2018, 02:00 PM
  #71  
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Mark --

Kind of a tangent, but... In hibernation season my car sits on stands on dollies so I can roll it around. You can do similar with even the cheapo harbor freight wheel dollies with a little 4-by-x something cribbing. I screwed on a rubber foot, like you find for small cabinets and such at the hardware store. Pokes through the hole in the lift pad to index the pad to the support. That way you can roll the car around to your heart's content, even sideways, to work on it or place it against a wall as I do when stored. The little $8 movers dolly with a few 4x sections on it might do in a $pinch if the floor is smooth/even.
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Old 10-13-2018, 10:22 PM
  #72  
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Originally Posted by dr bob View Post
Mark --

Kind of a tangent, but... In hibernation season my car sits on stands on dollies so I can roll it around. You can do similar with even the cheapo harbor freight wheel dollies with a little 4-by-x something cribbing. I screwed on a rubber foot, like you find for small cabinets and such at the hardware store. Pokes through the hole in the lift pad to index the pad to the support. That way you can roll the car around to your heart's content, even sideways, to work on it or place it against a wall as I do when stored. The little $8 movers dolly with a few 4x sections on it might do in a $pinch if the floor is smooth/even.
Thanks.. when i put the nice floor in... been planing to do some remods for years now, that might come in handy. however, the car is never in hibernation.

Btw, checked alignment , camber at 2.2 degrees front and 2.75 dgrees rear.... toe 0, and ride hight about 118mm. probably raising a little higher at Sonoma , already up from 110mm.
why did you want me to check aligment after the shock change, or was that just a double check before the runnoff advice.
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Old 10-14-2018, 03:18 AM
  #73  
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Check the alignment after ANY change that might affect ride height. Toe changes pretty dramatically with even small vertical travel when the suspension is so far from design height. You've already raised it 8mm from where you last aligned it, and plan to go even higher, so it will be toed in from what you have been seeing. The zero toe offers what feels like better initial turn-in, but any actual "advantage" disappears quickly once the weight settles and the outer tire loading is completed.

I restocked my aluminum box tube supply so I can make a new/better fixture set. Another winter project.

----

My suggestion for the dollies to roll the car around is for the ability to move the car while in the middle of a project. The fact that I do it for hibernation is for example only. I can roll it around without taking it outside, from its storage spot to the workbay. A smooth floor might be slightly better than the porcelain tile I have out there now, but not by much; I used 1/8" grout lines so the dolly wheels do't really drop in much. Anyway, it's an easy and inexpensive option that offers a possible solution to moving the car around when suspension tires wheels whatever are not installed.
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Old 10-16-2018, 02:10 AM
  #74  
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Bob,
All checked.. should be good. ill have a couple of tries to play with the shock settings ... plus maybe one time per session if something is obvious. lots of new things going on, but the tires are the most dominant change that should yield some good things in handling.
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Old 10-16-2018, 02:27 AM
  #75  
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Here are some of the results for my group and a few others today in testing. https://www.race-monitor.com/Results/Session/6532903



https://www.scca.com/events/1992733-...on-grp-1-run-3

Last edited by mark kibort; 10-16-2018 at 02:57 AM.
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