NC Alignment... No racing

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AndrewK636
Posts: 3
Joined: Mon Jan 17, 2022 11:47 pm

NC Alignment... No racing

Post by AndrewK636 »

Finally getting new tires on 06 NC. Passed on the Michelin and Conti Max performance Summer tires for Kumho Touring tire that has slightly less dry/wet performance for half the price. And much better wear rating. I'm just a spirited driver. No track/race in immediate future.

FM Stage II suspension. 300/200 spring rates. Right front is my highest at slightly less than 14".

So last set up was with real nice Conti's and FM suggested alignment:

Camber F/R: -1.0/-1.5
Toe: slight toe in both front and rear
Caster: FM suggestion was 5.0, but 5.5 is all we could get.

No major problems with that. Seem to have outer edge wear, suggesting I need more negative camber. Turn in was fine, but it pushes for sure.... when cornering I have to constantly turn more. And the back end never looses grip unless I turn TCS off. To me it seems that their lawyers told them to promote these understeer specs so limit liability. And that's ok, but I think I want to push it a little harder. I have very little Interstate driving at high speed, but definitely don't want a jittery car.

So my plan for new alignment is as follows:

Toe: Going for 0 deg to very small toe in front. Very small toe in rear.

Camber: To combat the understeer I think my front camber should be equal, if not greater than my rear. -1/-1.5 does't cut it. It seems the rear ramps up negative camber faster than the front under compression. I'm torn between one Goodwin recommendation of -1.2 all around and another Goodwin recommendation that gives some bias to the front: -1.8/-1.5. The later makes sense given the more progressive ramp up of negative camber on the rear.

Caster: Most suggestions for spirited drive are max out caster or something around 6-6.5. I don't see any negatives to more caster, and don't understand why FM recommendation are for 5.0 (and only 5.5 is available). I have power steering!

So based upon the headache induced findings many other threads, I'm going to ask for this (assuming Tires Plus techs are accommodating):

Toe: 0-slight toe in Front. Slight toe in rear. 0 F/.015 deg R (.075 deg per side)

Camber: -1.8F/-1.5R

Caster: 6-6.5. Previous posts state it's not much of a difference.

I don't care much about tire wear. They will dry rot before it's an issue. My only concern is if the set up is overly aggressive for me. I surely don't want the back end sliding out when I don't expect it, but maybe it would be nice for it to oversteer once in a blue moon.
Brian
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Re: NC Alignment... No racing

Post by Brian »

Indeed we like at least -1.2 all around. Beyond that minimum we start to give the front some advantage, which is why you have also seen us suggest -1.8 front with -1.5 rear. And if we go something like -2.2 front we do -1.8 rear or similar. The rear camber curve on NC is more aggressive than the front, so it pays off in balance at the limit once above minimum numbers to give the front a little more static camber.
Brian Goodwin
Good-Win Racing
www.good-win-racing.com
DavidI506
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Joined: Wed Jun 27, 2018 12:18 pm

Re: NC Alignment... No racing

Post by DavidI506 »

I have a 2007 PRHT with front and rear racing beat sway bars. The rest of the suspension is stock. I have the front bar set to the middle position and the rear bar to be firmer of the two settings. The alignment is still factory. As it is, I am finding way too much understeer. I want to get a more performance oriented alignment. I would like settings that will make it more playful and tail happy. Perhaps the occasional autocross. Mostly just spirited back roads. Does it make sense to shoot for slightly more negative camber in the front than the rear? Zero toe in the front? Would I be better off setting the front swaybar to the softest setting?
Brian
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Re: NC Alignment... No racing

Post by Brian »

Yes, try some front toe zero for a front end more willing to grab on the way into the turn. Factory alignment was a mess on these cars, it tended to make them numb with lots of toe in all around and not near enough camber. And the factory alignment was not a set of numbers so much as a range of numbers and anything roughly in the range was considered good to go, even if inconsistent corner to corner.

At stock height the camber is limited but try to indeed get more front, something like noted in my first post above, -1.8 front and -1.2 rear. Keep toe in at the rear but just a little, like 1/32 per side toe in. If that still does not get the rear as playful as you want then make that front sway bar one more step softer, the hole nearest bar ends at the front.
Brian Goodwin
Good-Win Racing
www.good-win-racing.com
DavidI506
Posts: 2
Joined: Wed Jun 27, 2018 12:18 pm

Re: NC Alignment... No racing

Post by DavidI506 »

Thanks very much Brian. I’ll try exactly that
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