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F-Body Road Racing and Autocross Forums _ General Discussion _ Need opinions on a lot of questions
Posted by: FASTFATBOY Mar 12 2013, 02:41 PM
Keep in mind this is NOT a dedicated track car, it is a full on street car( I long hauled the Power Tour with it, and may do it again) that gets track day'd.
Keep in mind, I did my first event with a good seat in the car and it was very cold 45* high. Dunno if this was the reason for the push or not but I pushed the car further than I ever have that weekend as it was much easier to drive it hard.
I have Strano springs, 1 LE front bar, stock rear bar, Koni Da on front SA on rear, UMI rotojoints on rear, LCA relocation brackets. UMI frame connectors.
I am debating going after more grip. Since I put a seat in the car I realize whats going on with the car when you push it hard.
275 NT-01/ R888 vs a 315 NT-05, I am looking at cost, I have 2 sets of 17x9.5 wheels. If I move to a 315 I will have to buy all new wheels/spacers/studs and consider wheel bearing wear. The 315 NT-05 is a cheaper tire than the 275 NT-01 or R888 and will last longer I would think. Thoughts on which has more grip and life?
I have noticed a push, it has always had one but now seems much worse on high speed corners .
More rear bar help this?
More camber help this?
Am I trying to enter the corner with too much speed?
I only have 1.1 camber in the front as thats all I can get with stock stuff....I am killing the left front outer edge of the tire.
If I slot the lower control arm holes will I have enough tie rod end to set toe? They look way out now.
Would you buy offset LCA bushings and slot, or one or the other?
Or buy a shorter upper control arm?
I feel I need at least 1.8 camber but how will this effect street tire wear?
Anyone used the Global West front lower control arm bushing kit? Thoughts?
Thanks guys all opinions welcome.
Posted by: trackbird Mar 12 2013, 03:13 PM
Based on being a street car...stick with the 275 tire. They fit better and they have a better chance of coming up to temp during more sedate driving (you may never get them "hot", but you'll NEVER get a 315 hot on the street). Less trammeling and rubbing issues too.
Put a 35mm solid front sway bar on it. That will help with the camber loss during body roll. It's counter intuitive to add front bar when you have understeer, but these cars lose camber during body roll. Less roll means less camber loss. So I'd start there. I ran the Global West upper front control arms and I could get -2.2 camber and all the castor I ever wanted (up to about 9 degrees).
Make sure your rear LCA's are "flat" at ride height (or even slightly lower in the front). That causes roll understeer instead of roll oversteer. I never ran relocation brackets on my cars, but if you do....you typically need to drill a hole right between the bracket and the axle bracket (basically through the weld) to get the right height.
Then I'd try a 22mm hollow (or 21mm solid...or the hellwig adjustable kit...which I have one of for sale) on the rear.
Posted by: Steve91T Mar 12 2013, 03:19 PM
Before I started the CMC build, my car was a street/track car. Strano spring, Koni adjustable front shocks and Bilstein revalved rears from Strano, Hotchkis front bar, strano rear.
My problem with the Camaro has always been oversteer. It always seemed the front had twice the grip the rear did. This was before Strano's help. I had SLP springs and Hotchkis bars, front and rear. He explained his spring rates and his softer rear bar would help. It did, greatly. Perfectly balanced.
All that nonsense being said, could it be your driving technique? These cars are pretty sensitive to weight transfer. I know you have a ton of track experience, but maybe you picked up a bad habit over the years? What happens if you trail the brakes just a tad going into a tun? Or at least lift enough to set the fronts? If you feel you really do have a problem, what about a sway bar change? They are pretty damn cheap for the amount of change in handling you get. I'm selling my sway bars if you are interested.
I know I keep using this video, but I haven't been on the track in over a year, so it's the best one I have.
You don't have to watch the whole thing, but notice I'm fairly smooth with my turn in with all turns but one. I also trail brake almost always, just a little.
Fast forward to 50 seconds. The sharp, low speed left hand turn, followed by a sharp right hand turn is the only place at VIR where I will push. So, I not only trail brake, but I actually throw the car into the turn. (notice the rapid wheel movement).
Do you have any videos that show the push?
http://www.youtube.com/watch?v=dbvX2z4Ta3E&list=UUt_D0QaGGJHF1A7yAWTwq2A&index=9
Posted by: StanIROCZ Mar 12 2013, 03:57 PM
I think more camber will help with the push and reduce tire wear, so yeah, go for it. On a 3rd gen it is easy to tweak the alignment for a 'street' and 'track' settings.... not sure if that is an option for you or not. Otherwise you will have to compromise.
My advice for tires is to get a track set and street set. The cost of the additional set of rims will payoff immediately if you can find a source for scrubs from a pro/semi pro team in your area, and with the added grip the fun factor is doubled 
Whatever size tire you can readily get from them is what you should go with, assuming it is in the 275-315 and 17-18 ranges you have choices in cheap wheels and they will fit the car. I can get a set of lightly used scrubs mounted and balanced for the cost of 1 tire new…. That sure as heck beats burning up a set of Nittos once a year 
Posted by: FASTFATBOY Mar 12 2013, 04:46 PM
Put a 35mm solid front sway bar on it. That will help with the camber loss during body roll. It's counter intuitive to add front bar when you have understeer, but these cars lose camber during body roll. Less roll means less camber loss. So I'd start there. I ran the Global West upper front control arms and I could get -2.2 camber and all the castor I ever wanted (up to about 9 degrees).
Make sure your rear LCA's are "flat" at ride height (or even slightly lower in the front). That causes roll understeer instead of roll oversteer. I never ran relocation brackets on my cars, but if you do....you typically need to drill a hole right between the bracket and the axle bracket (basically through the weld) to get the right height.
Then I'd try a 22mm hollow (or 21mm solid...or the hellwig adjustable kit...which I have one of for sale) on the rear.
I will keep a 275 setup separate for street only driving, the setup I am asking about will be strictly trtack use.
My rear arms are almost flat with with ground, slight uphill to the body.
Posted by: trackbird Mar 12 2013, 07:20 PM
Uphill to the body causes roll oversteer. My apologies for misunderstanding, I read "street car" as "one set of wheels for all around use". 315's will typically be faster around a track. But, if you're only running HPDE, you really aren't out to "win" (I think it was Mitchntx that once said "you can't win practice" during a session at the NASA nationals). So, is the extra tire/wheel expense worth the lap time difference? The problem with HPDE is that it's the "super unlimited" class of racing. There are no lap times and no trophies, but everyone shows up to be the fastest car there...with no rules. So, it's an arms race to "win" the open track day. If it were me, I'd run the 275's and be done with it (wheels are cheaper, tires are probably cheaper, etc). But 315's will typically be faster on a track. Or I'd take Stan's advice and buy wheels that allow you to buy used tires from one of the race series and run those.
I think I'm getting old... 
Posted by: Blainefab Mar 12 2013, 10:08 PM
What are your alignment settings and tire pressures, what changes did you make with them to cure the push, and what were the results of those changes?
Posted by: FASTFATBOY Mar 12 2013, 11:30 PM
Alignmnet is 1.1 camber(maxed out) 0 toe.
Alan the track was VERY cold, the high that day was 45* so I treated it like a wet track(my best guess of what to do low grip is low grip). I softened shock compression and lowered tire pressures 2 lbs all around from where I usually start the session. It seemed to have helped.
I found this today, this is the left front shock.This happened at the last event as it is a fresh break. The nut is not cross threaded, I had a squeak in the front end and went looking to find it as the car has never made a peep of any kind.
Anyone Koni "connected" to help me out? Shocks about 13 k on them, were new on the car when I bought it. I have no paperwork.
Posted by: FASTFATBOY Mar 12 2013, 11:41 PM
My problem with the Camaro has always been oversteer. It always seemed the front had twice the grip the rear did. This was before Strano's help. I had SLP springs and Hotchkis bars, front and rear. He explained his spring rates and his softer rear bar would help. It did, greatly. Perfectly balanced.
All that nonsense being said, could it be your driving technique? These cars are pretty sensitive to weight transfer. I know you have a ton of track experience, but maybe you picked up a bad habit over the years? What happens if you trail the brakes just a tad going into a tun? Or at least lift enough to set the fronts? If you feel you really do have a problem, what about a sway bar change? They are pretty damn cheap for the amount of change in handling you get. I'm selling my sway bars if you are interested.
I know I keep using this video, but I haven't been on the track in over a year, so it's the best one I have.
You don't have to watch the whole thing, but notice I'm fairly smooth with my turn in with all turns but one. I also trail brake almost always, just a little.
Fast forward to 50 seconds. The sharp, low speed left hand turn, followed by a sharp right hand turn is the only place at VIR where I will push. So, I not only trail brake, but I actually throw the car into the turn. (notice the rapid wheel movement).
Do you have any videos that show the push?
http://www.youtube.com/watch?v=dbvX2z4Ta3E&list=UUt_D0QaGGJHF1A7yAWTwq2A&index=9
http://www.youtube.com/watch?v=bfFDSB6wzrc
Turn 2-3-4 is one loooong right hander(1:55), it seems I was going through there slower and slower just to get the left front to have ANY grip. Was the broken shock causing this?? When you see the rumble strip on the right I should be able to go flat on the floor in 4th gear and hold it there all the way up the hill into turn 5 braking zone., you hear me crack the gas open and on and off the gas but it was way past there before I can go to the floor with the gas.
And in turn 12, as soon as the car settles after turn in(1:14) I should be on the floor in 4th up that hill, no way could I do it.
Here is a track map
I do trailbrake, although I didnt KNOW I was doing it as when I was learning to drive the car it was a natural thing to do as it helped the car turn. When I saw video of me from a car behind me it was pointed out by a buddy.
EDIT
Now that I think about it, the car felt funny under braking especially into 7, it felt like the left front was hitting the bumpstop, it was dropping way more than the right front under hard braking. At 2:30 you can see the front of the car "bob" up and down, thats not me doing that.
With effectively having no shock on the left front is this what killed the outside edge of that tire?
Posted by: Blainefab Mar 12 2013, 11:45 PM
You just need the tophat, not the whole shock. Call Koni or Strano. Fix the busted stuff, grind the camber slots to get -2deg camber, buy some toe plates, play with toe to see how the car responds. With everything in the ballpark, a small change (2 flats on the tie rods) in toe and/or tire pressure (2psi for example) should give you a noticeable change in the way it turns. Fiddle with that stuff for a couple events, adjust your driving appropriately, then add more go fast parts.
Posted by: FASTFATBOY Mar 13 2013, 12:23 AM
Alan the shaft is broken. Its a DA shock, how do you change just that part of the shock? What causes that?
What are "toe plates"?
Posted by: Blainefab Mar 13 2013, 11:04 AM
Alan the shaft is broken. Its a DA shock, how do you change just that part of the shock? What causes that?
What are "toe plates"?
Pull down the rock shield, look under the cup shaped tophat - you'll see a jam nut - loosen the jam nut, tophat unscrews from shock shaft. Replace hat, tighten nut.
The jam nut is a bitch to get a regular tool onto, and it is tight. This guy makes a tool that works:
http://www.frrax.com/rrforum/index.php?showtopic=8350
Toe plates:
http://www.racerpartswholesale.com/product/LAR_79500_Longacre_Toe_Plates/Toe_Gauges_And_Laser_Plates/?r=gs&gclid=CM6SvNPF-bUCFegWMgodA2gA3g
Posted by: FASTFATBOY Mar 13 2013, 11:59 AM
Alan the shaft is broken. Its a DA shock, how do you change just that part of the shock? What causes that?
What are "toe plates"?
Pull down the rock shield, look under the cup shaped tophat - you'll see a jam nut - loosen the jam nut, tophat unscrews from shock shaft. Replace hat, tighten nut.
The jam nut is a bitch to get a regular tool onto, and it is tight. This guy makes a tool that works:
http://www.frrax.com/rrforum/index.php?showtopic=8350
Toe plates:
http://www.racerpartswholesale.com/product/LAR_79500_Longacre_Toe_Plates/Toe_Gauges_And_Laser_Plates/?r=gs&gclid=CM6SvNPF-bUCFegWMgodA2gA3g
Duh, I know what toe plates are.
This is a double adjustable shock, the adjuster is in the part that screws off?
Posted by: Steve91T Mar 13 2013, 12:37 PM
You have two adjusters? Didn't know they made them. Mine are single adjustable. I had to remove my hats to get the coil over sleeves installed. The jam nut wouldn't budge, so I called Koni and asked them what that hat was for. They said only to hold the dust shield and I could cut it off if I wanted. Wouldn't hurt a thing. So off they came. Now I can get to the jam nut easily if I need to.
Where are your adjusters? Why not call Koni and see what they say? Btw, how does a shock break like that?
Posted by: FASTFATBOY Mar 13 2013, 01:49 PM
Where are your adjusters? Why not call Koni and see what they say? Btw, how does a shock break like that?
I am about to call Koni in a minute.
Yes they are Da's. The top is rebound adjust, bottom "clicker" is compression. You adjust that with a flathead screwdriver.
Posted by: FASTFATBOY Mar 13 2013, 02:02 PM
Koni says that part of the shock is in fact THE shaft and does not come off. Alan do you have a pic of what you are talking about?
They will not help me as I am not the original purchaser of the shock.
Posted by: trackbird Mar 13 2013, 02:09 PM
They typically say DA's have no warranty since they are for racing use. I had mine rebuilt by truechoice (my rear DA's...after I smashed one) and I wouldn't do that again.
Posted by: FASTFATBOY Mar 13 2013, 02:29 PM
Why not? Price, turn around time? What?
Posted by: trackbird Mar 13 2013, 02:36 PM
They leaked in pretty short order. They changed the gas pressure from Koni specs (I wanted a "stock rebuild" and I had the shock and the shock shaft shortened). By the time I was done, I spent $500+ on rebuilding a pair of rear shocks and they didn't hold up well at all. Next time I'll toss them and just buy a new set (or maybe send them directly to Koni).
Posted by: FASTFATBOY Mar 13 2013, 03:03 PM
Koni has a 5-7 week turnaround, ughhhhhhh.
Posted by: trackbird Mar 13 2013, 04:31 PM
Mine likely took 3 weeks or so...and I dropped them off at truechoice (about 8 miles from my house). I'd see if you could sell them to someone looking for "cores" (wanting to build something custom without cutting up brand new shocks) and just buy new. Rebuilding seems to result in spending nearly as much as new ones in many cases. But I haven't looked in a while.
Posted by: FASTFATBOY Mar 13 2013, 05:22 PM
I found a pair on E bay for $499, what ya think? Or buy one new from Summit for $386?
Posted by: Steve91T Mar 13 2013, 05:48 PM
I still want to know how it broke like that.
Posted by: FASTFATBOY Mar 13 2013, 06:22 PM
I sent a NASTY message on Facebook to Koni and Alan was right about it unbolting from the top. When I called Koni North America the tech guy Mason didnt know that....WTF?
The guy from FB is gonna call me back in a few.
Alan I need that tool or need to borrow one and send it back.
BTW Strano is off the reservation till next Tuesday.
Posted by: FASTFATBOY Mar 13 2013, 07:57 PM
Lee Grimes called me back, and he said when these shocks come back trashed he has them take the tops off and save them. He is sending me one free of charge.
How does the dust cover come off without damaging it Alan??
I will make the tool and fix it.
Posted by: FASTFATBOY Mar 13 2013, 07:59 PM
Lee Grimes @ Koni said it was most likely installed with the upper nut loose and it finally snatched it apart.
Posted by: tonycook Mar 13 2013, 08:43 PM
Do you know where to elongate the slots for more camber? I can try to get you a photo if I get home at a decent time in the next few days. Doing your own alignment is not a big deal after you do it a few times.
I think I made my Koni tool from an offset box wrench. Don't bother starting with a cheap wrench unless you want to waste your time. I tried cheap Harbor Freoght wrench and it was useless.
Not sure if any sponsors sell toe plates, but Ron at Discovery Parts has them.
Posted by: Steve91T Mar 13 2013, 08:47 PM
What does the toe plate do? Anything a couple of straight edges taped to the wheels/tires wouldn't do?
The dust covers snap off, but not without a fight.
Posted by: FASTFATBOY Mar 13 2013, 08:52 PM
The dust covers snap off, but not without a fight.
I got the cover off, the nut is encased in the steel that holds the dust cover on, Can I just grab and turn that?
How do you the nut exposed to take it off? Also how do you hold the shaft without marring it.
Was the wrench a 21mm? I will make mine out of a socket most likely.
Toe plates are plates you lay flush against the face of the tire to set toe with a two tape measures.
How do you set camber/caster at home?
Posted by: Steve91T Mar 13 2013, 09:04 PM
Seems like for a hell of a lot less than $60, I can make something just as effective. That's why I'm asking.
So those hats and jam nuts, that's why I ended up trimming the hat off. It's a terrible design and is a real bitch to get to. I believe you have to hold the hat in a vise and then with your special tool, loosen the jam nut. A while ago, I had to replace a hat/shaft and I paid a machine shop $20 to take care of it. He put it in a vice and chiseled it off and then back on again. Buggered up the jam nut, but it still worked just fine.
Like I said, Koni told me the dust cover is the only reason that stupid hat is there. Cut the fucker off. If you really want a dust cover, I'm sure you can come up with a different way to secure it.
I took my time and doused the hat that I was cutting with water to keep it cool. Now if I need to remove the shaft, I can use a normal wrench.
Just a thought.
Posted by: Blainefab Mar 13 2013, 09:35 PM
How does the dust cover come off without damaging it Alan??
I will make the tool and fix it.
Lee is the goto guy at Koni, I couldn't remember his name.
Just pull down on the dust cover, might need a screwdriver to help, but should pop off without damage.
You can copy mine from the pic if you want. I don't have a loaner. Use an impact socket. it's 24mm, but 15/16" fits better.
There is a rubber grommet that you need to pick out (toss it) to expose the jam nut.
Posted by: Blainefab Mar 13 2013, 09:38 PM
You can make your own - cut slots at the same height for the tape measure to engage. The store bought ones have a kick out on the bottom so the contact bulge doesn't keep the plate from laying flat on the tire or rim.
Posted by: Blainefab Mar 13 2013, 09:44 PM
Use the flange on the camber bolt/nut heads as a guide - grind the slots outward till the flange is flush with the outer edge of the Kmember stamping. It will be about 3/16" of extension of the slots.
Camber and Caster bolts all the way out, set toe for 1/16" out will put you in the ballpark for the track. TQ nuts to 90#ft.
To get it to track dead straight on the freeway with the wheel centered, bring it to a shop for a spec alignment.
Posted by: FASTFATBOY Mar 13 2013, 10:19 PM
How does the dust cover come off without damaging it Alan??
I will make the tool and fix it.
Lee is the goto guy at Koni, I couldn't remember his name.
Just pull down on the dust cover, might need a screwdriver to help, but should pop off without damage.
You can copy mine from the pic if you want. I don't have a loaner. Use an impact socket. it's 24mm, but 15/16" fits better.
There is a rubber grommet that you need to pick out (toss it) to expose the jam nut.
I have a Craftsman 12 point offset box end 15/16 wrench I will cut and try first.
I see the shaft doesnt go anywhere near all the way up into the shock, So just grab it as close up to the top as I can with whatever I can?
I need the dust cover, I wouldn't do away with it. Do whatever you can to keep the shaft clean as it will extend the life of the shock.
Posted by: FASTFATBOY Mar 13 2013, 10:21 PM
Use the flange on the camber bolt/nut heads as a guide - grind the slots outward till the flange is flush with the outer edge of the Kmember stamping. It will be about 3/16" of extension of the slots.
Camber and Caster bolts all the way out, set toe for 1/16" out will put you in the ballpark for the track. TQ nuts to 90#ft.
To get it to track dead straight on the freeway with the wheel centered, bring it to a shop for a spec alignment.
Will I have enough tie rod end to do the toe adjustment safely?
Will 1/16 toe out wear tires?
Posted by: Blainefab Mar 13 2013, 11:43 PM
How does the dust cover come off without damaging it Alan??
I will make the tool and fix it.
Lee is the goto guy at Koni, I couldn't remember his name.
Just pull down on the dust cover, might need a screwdriver to help, but should pop off without damage.
You can copy mine from the pic if you want. I don't have a loaner. Use an impact socket. it's 24mm, but 15/16" fits better.
There is a rubber grommet that you need to pick out (toss it) to expose the jam nut.
I have a Craftsman 12 point offset box end 15/16 wrench I will cut and try first.
I see the shaft doesnt go anywhere near all the way up into the shock, So just grab it as close up to the top as I can with whatever I can?
I need the dust cover, I wouldn't do away with it. Do whatever you can to keep the shaft clean as it will extend the life of the shock.
Don't touch the shaft, put the hat in a vise
Posted by: Blainefab Mar 13 2013, 11:45 PM
Use the flange on the camber bolt/nut heads as a guide - grind the slots outward till the flange is flush with the outer edge of the Kmember stamping. It will be about 3/16" of extension of the slots.
Camber and Caster bolts all the way out, set toe for 1/16" out will put you in the ballpark for the track. TQ nuts to 90#ft.
To get it to track dead straight on the freeway with the wheel centered, bring it to a shop for a spec alignment.
Will I have enough tie rod end to do the toe adjustment safely?
Will 1/16 toe out wear tires?
The parts I've used have had enough threads - pull a tie rod end off and measure the thread length to be sure.
Yes, toe out will wear tires and can cause tramlining.
edit - added 'end' to tie rod
Posted by: FASTFATBOY Mar 13 2013, 11:57 PM
Alan, you are the man.
Posted by: FASTFATBOY Mar 16 2013, 02:13 PM
My cut 15/16 wrench worked ok, I had to use a long punch to break it loose but it worked.
Thinking about when this happened.......... I was on track and entered turn 5(very hard left hander) at Barber and the car just snapped around and spun out(about 45-50 mph there). I was VERY confused as to why this happened as I did nothing different into that corner. I am ALWAYS seeing if I can crack the gas open sooner and sooner in every corner as it settles the car but it has never ever snapped around like that.
It was all normal then SNAP I was going around backwards.
Posted by: FASTFATBOY Mar 20 2013, 05:43 AM
I am all fixed and riding again, I replaced the strut top hat as the hole was elongated.
The strut was originally put on loose, the nut on the top was about 5-6 threads higher from where it is now.
Thanks for all the help guys.
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