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Not a waxer
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Sounds like you have the car really well sorted out David! I agree, guys who haven't driven one don't know what a knife edge it is (40 year autocrosser who I often run with that competes in E-Mod always says "These kids in those damn rally cars (Subarus) and new Corvettes don't realize that even Ray Charles could go fast in one of them" :lol:).

Cheers,
Jeff
 

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If I were to get serious about autoX instead of the occasional casual event I do now, CAM would be the way to go.
Last time I checked, my porker was 2,410 lbs. Wouldn't take much ballast to get to 2450. Tires would be a problem for me. Right now, I run the NT01 year round which is 100 treadwear and throws me into XP. I would have to get 18" wheels and run the rival in 275F and 315R and if I was careful, everything might fit. Or be ridiculous and run the RE71 in 255s all around? It's a better tire, but you loose some width.

Suspension setup question: Last year, I was running -1.75 camber with a 1/16" toe in front and a stock 8.8 (essentially no camber in the rear). I increased the front camber to -2.75 and toe to 0 and it is now extremely tailhappy in the rear, especially in transitions like a slalom. How much front camber is typical for a solid axle car with essentially no rear camber? Then, the question is, do I try to keep the extra front camber and stiffen the front with stiffer springs or a front sway bar?
 

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Unconventional Builder
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Suspension setup question: Last year, I was running -2.25 camber with a 1/16" toe in front and a stock 8.8 (essentially no camber in the rear). I increased the front camber to -2.75 and toe to 0 and it is now extremely tailhappy in the rear, especially in transitions like a slalom. How much front camber is typical for a solid axle car with essentially no rear camber? Then, the question is, do I try to keep the extra front camber and stiffen the front with stiffer springs or a front sway bar?
Go here we just had a lengthy discussion.
“I’m a believer” in anti sway bars
 

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Not a waxer
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11,593 Posts
If I were to get serious about autoX instead of the occasional casual event I do now, CAM would be the way to go.
Last time I checked, my porker was 2,410 lbs. Wouldn't take much ballast to get to 2450. Tires would be a problem for me. Right now, I run the NT01 year round which is 100 treadwear and throws me into XP. I would have to get 18" wheels and run the rival in 275F and 315R and if I was careful, everything might fit. Or be ridiculous and run the RE71 in 255s all around? It's a better tire, but you loose some width.

Suspension setup question: Last year, I was running -1.75 camber with a 1/16" toe in front and a stock 8.8 (essentially no camber in the rear). I increased the front camber to -2.75 and toe to 0 and it is now extremely tailhappy in the rear, especially in transitions like a slalom. How much front camber is typical for a solid axle car with essentially no rear camber? Then, the question is, do I try to keep the extra front camber and stiffen the front with stiffer springs or a front sway bar?
Brian,
Power or manual steering? If you have power and go to approximately 8 degrees positive caster you'll get a bunch of negative camber gain on turning. With manual to be manageable your caster is kind of limited to 3 degrees or so which doesn't get so much camber gain (my opinion is that it's really tough to be fast and keep up with one of these cars with manual steering but thats a well documented discussion for another topic...). FWIW, on my 3 link car I run NT-01 also with 1.5 to 1.75 negative camber, 8 positive caster and about 3/32 toe in along with a 750/500 spring combination and no bars. It's just a touch loose but not "tail happy" (unless I do something stupid ;)).

Jeff
 

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Jeff, the car has power steering and I have the caster maxed out with the current upper links, I think it was around 4.5-5* caster. I need a couple of shorter links to get more caster. Sounds like that would be a good direction to go, as the tire wear would improve by running less negative camber too. That and I probably should set it up tight and creep up on a looser setup as my comfort and skill level hopefully improve.


Brian,
Power or manual steering? If you have power and go to approximately 8 degrees positive caster you'll get a bunch of negative camber gain on turning. With manual to be manageable your caster is kind of limited to 3 degrees or so which doesn't get so much camber gain (my opinion is that it's really tough to be fast and keep up with one of these cars with manual steering but thats a well documented discussion for another topic...). FWIW, on my 3 link car I run NT-01 also with 1.5 to 1.75 negative camber, 8 positive caster and about 3/32 toe in along with a 750/500 spring combination and no bars. It's just a touch loose but not "tail happy" (unless I do something stupid ;)).

Jeff
 

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Not a waxer
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11,593 Posts
Jeff, the car has power steering and I have the caster maxed out with the current upper links, I think it was around 4.5-5* caster. I need a couple of shorter links to get more caster...
Sounds like you have the later upper arms with the angled ball joint plates. Different sleeves are not necessary---when using these arms I cut about 3/16" to 1/4" from both ends of the rear adjuster sleeve and a similar amount from the male stubs so that they don't bottom internally. Doing this will allow you to reach 8 degrees or so of caster along with negative camber.

Jeff
 

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Crisisrider
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164 Posts
Discussion Starter #27 (Edited)
Jeff,Trevor I used 9inchfloaters.com for my hub assemblies. Just had to mill the assy down a little to fit my housing. I welded them in at 0-deg and used strut bars and a custom bracket over the chunk to mount. The 8.8 tubes are so flimsy I was able to pull in over 1.5-deg camber and i did a mild 1/32 tow in. I street the car so wanted the option to go back to 0-deg. Another benefit I figured from doing it this was was no more axle flop an any direction. I originally went with the floater because of some serious pad knockback on the Wilwoods which everyone said it was axle lash until I posted a video showing the axle flex. They have some super nice cambered axles but one I saw was over 5K...nah!

David
 

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Moderator
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That's a serious rear end set up. Very nice.

Do you have a good way of reacting the brake torque? It seems that if the axles tubes are that 'loose' in the center housing that they might twist.
 

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6,137 Posts
I figured it was axle flex causing the knock back problem since the IRS has the same issue. That's why I am looking into a full floater. Also,my axles flex so bad the end seals leak. It's far worse this past season because I switched to 335 A7s. I'll check the website out, thanks.

Mike, his tubes are still fixed, the control arms are deflecting the tubes to create the angle.
 

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Crisisrider
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164 Posts
Discussion Starter #30
I can say the rear felt way more solid after I did this but the camber is what really made the rear so much more predictable, that and removing the rear bar. I also have been having my seals leaking a bit, I was thinking it may be more from heat expansion like the mustangs have so I am going to put a better vent on the housing since it originally would spit out of the stock vent. I got an accordian style reservoir but it seems to be too stiff to allow for expansion, prob just do a hose and breather up high....and look closer at the seal when I tear it down again since it is only on the passenger side. David
 

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FFCobra Craftsman
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22,281 Posts
I would have to get 18" wheels and run the rival in 275F and 315R and if I was careful, everything might fit. Or be ridiculous and run the RE71 in 255s all around? It's a better tire, but you loose some width.

Suspension setup question: Last year, I was running -1.75 camber with a 1/16" toe in front and a stock 8.8 (essentially no camber in the rear). I increased the front camber to -2.75 and toe to 0 and it is now extremely tailhappy in the rear, especially in transitions like a slalom. How much front camber is typical for a solid axle car with essentially no rear camber? Then, the question is, do I try to keep the extra front camber and stiffen the front with stiffer springs or a front sway bar?
1- Around here the street tire guys I have talked to like the RE71Rs in spring and fall but like the BFGs in the hot part of the summer. SO they are not that much different. Also note that there is a Rival S 1.5. I don't know the difference though so I would call BFG.
2- If the tail happy is mostly in slaloms that is a transitional characteristic which is best dealt w/ via shocks. I run QA1 double adjustables and crank the fronts up to quite stiff for AX and then back down for the street. SInce the street tire guys are restricted in how much camber they can run I don't have any info on them. But w/ my A7s I run 3.0-3.5 in front and 2.5 in the rear. For me it depends on the course layout. A lot of slaloms means super stiff front shocks. Less slaloms and more longer duration turns means less front shock.
3- Other than shocks, I would probably go for more front spring. If you don't have a front bar though, that would be first. Forte has front bars in 3 thicknesses. I am running the 1 inch but would recommend the 7/8 as a more all around bar.
4- As I have slowly increased front springs, bars, and shocks, one kind of a side effect is increased steering response. Because of that I run a more street front toe-in spec of between zero and 1/8 IN. Makes for a lot nicer drive to and from the AX also. Running toe out w/ A7s is really darty at 70-80 mph.
 

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Crisisrider
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164 Posts
Discussion Starter #32
I also like the RE's but they do not get wide enough for our setup, I do know the BFG 1.5 does not apply to the wider tires, maybe up to a 225 or 245 but it would be nice since the new 1.5 BFG has a stiffer sidewall which was the biggest complaint of the BFG lacking quick response turn in.

David
 

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+1 here for the Lousteaus; not only have they built a great car, they're terrific wheelmen and entertaining company. A lot of what we've done to our car comes from them.

As I posted elsewhere, we went to 19x11 American Racing wheels on our MkIII; with the 8.8" rear end, they fit just fine in back. Not so fast on the fronts; they mounted ok, and miss the fender well for the most part, but rub the center of the fenders under full load. We're now running 305/30R19 Bridgestone RE-71Rs on the rear and 285/30R18s on front. The car seems to like a little rake, and with a new front sway bar, it noses down and turns in really quickly. We'll need to flare the front fenders, so the search for a good fiberglass man, with a hole in his schedule before, sayyy, 2019, continues.

Of course, it still oversteers some, but it's far tamer than it used to be. My codriver fashioned new rear LCAs out of splined aluminum stock and Heims, and that enabled us to cure a thrust angle problem (the rear axle wasn't square with the frame). We also sourced Penskes from Guy Ankeny, per David's recommendation.

BTW, we're currently sprung a little lighter than David. His rear axle is to be envied; we're looking at building a floater, but we're not getting the pad knockback we feared. Still, I replaced the rear axles and seals at 15,000 miles.

Re weight: with the Wilwood upgrade and the addition of 2 of the 19" AR wheels, and a half a tank of gas, we crossed the plate at 2503 lbs at the Spring Nationals at Lincoln last weekend.
 
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