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TitaniumTT 03-10-2009 05:31 AM

Looking for alignment starters - FC
 
So in about 2 weeks, if all goes according to plan, I'll be heading up with a buddy to his friends race shop to set the alignment on my FC. I'm looking for some suggestions as to where to start with camber, toe, etc.
Car is an '88 SE, 13B-RE swap, stance c/o's, RB sways, MT hiem links, full poly bushings, custom front, arm, and rear supports, rear camber adjuster. I'll be running BBS RII's, 17x8 +35 & 17x9 +35 with Azenis 615, 235/40 & 255/40.

Looking for a more aggressive, geared towards auto-x rather than lets make the tread last for the street setup. What have you guys found to be a good baseline?

Also, torn between the Azenis 615 and the NT-01's. The NT-01s will run about $150 more. Worth it?

P71 03-10-2009 08:22 AM

The NT01's aren't $150 faster than the Rt-615's, stick with them. You'll want -1.5* to -2* of camber and as much caster as possible. Some say a slight toe-out, others say toe-in, I like them as perfectly straight as possible.

Rogue_Wulff 03-10-2009 10:06 AM

Toe out helps turn in, but reduces straight line stability and speed. Toe in will increase straight line stability, but at the loss of turn in response. Autocross is mostly turns, with few real straights.
Otherwise, I concur with the above suggestions.

Kentetsu 03-10-2009 03:12 PM

I run zero toe on the streets, then tweak in a bit of toe out when I get to the autocross events. Helps a lot with the really tight turns...



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TitaniumTT 03-10-2009 04:12 PM

Excellent. Thanks guys. :icon_tup:

Any suggestions for the rear?

Regarding the NT-01 vs Azenis 615, I've been told that for a primarily driven street with the occasional auto-x, the NT-01, even with it's lower tread rating, will actually last longer because of the compound. Stickier = less likely to spin = longer life, by 2-3x making them cheaper in the long run. Any thoughts on this?

SPICcnmFD 03-10-2009 04:37 PM

I'd go zero toe(F & R) since you street drive it primarily. Toe out makes it twitchy, especially under hard breaking, not worth the crisper turn-in IMO on a mostly street driven vehicle.

I'd go with 1.5* negative camber front and rear to start with. It's going to eat the insides off on the street the more you put into it(well take out). The only real way to tell is set it and drive it and measure the tire temps and wear.

P71 03-10-2009 07:32 PM

Azenis last longer than NT01's, the Nittos are slightly stickier. By slightly I mean a National level driver *might* see a tenth or two on a 90-second course. Get the Falkens.

CLH 03-10-2009 08:30 PM

Not to get off of the alignment question, but why run so much tire size stagger? If you want the car to turn better more rubber up front is a good start ;-)

With the Stance coilovers and the right offset you should be able to fit a 245/40-17 up front. I can fit a 245/40-17 Ecsta MX on a 17x8 wheel up front on my '89 with the Stance setup. The Falkens or Nittos can't be that much wider in cross-section than the Kumhos (if wider at all).

Just sayin...

Edit: Just realized that there's no such thing as a 245/40-17 RT-615 or NT-01 :(

P71 03-10-2009 09:19 PM

245/45/17 is the common size, that's why. Josh has even wider wheels on his FC with flared fenders.

josh18_2k 03-10-2009 09:29 PM

ok heres my recommendation. stick with your original tire size (235,255). anything wider up front is really pushing your clearance, unless you wanna run spacers and roll fenders.

Direzza Z1 Star Specs are the new hot shit around town. I don't know how their pricing compares with Azenis, but if they're close enough, go Z1's. They are much better in wet, and slightly better in dry. Wet performance is worth choosing them.

alignment- no more than 1.5 camber in back, and at least 2.5 in front. the front needs camber to work right! my plates max at 2.5, and i need more to maximize the tire. dont worry about tire wear. drive harder if you want them to wear evenly lol
and yah, zero toe all around. with your offsets the car should be stable enough.

SPICcnmFD 03-11-2009 08:19 AM

Quote:

Originally Posted by josh18_2k (Post 76359)
alignment- no more than 1.5 camber in back, and at least 2.5 in front. the front needs camber to work right! my plates max at 2.5, and i need more to maximize the tire. dont worry about tire wear. drive harder if you want them to wear evenly lol
and yah, zero toe all around. with your offsets the car should be stable enough.

:icon_tup: That's what I have on my FD and it's wears tires evenly when driving hard. On the street it eats the front insides pretty quick, which is why I suggested less up front. I'd do stock Caster setting FWIW, but that's just me.

josh18_2k 03-11-2009 11:32 AM

your FD actually has a camber curve, so you can get away with less.
FC's start to lose camber beyond a certain point, cuz macpherson struts are gay.

TitaniumTT 03-11-2009 11:50 AM

Quote:

Originally Posted by CLH (Post 76349)
Not to get off of the alignment question, but why run so much tire size stagger? If you want the car to turn better more rubber up front is a good start ;-)

The wheels are staggered by an inch, and I want to keep the same tire width to wheel width.

Quote:

Originally Posted by CLH (Post 76349)
With the Stance coilovers and the right offset you should be able to fit a 245/40-17 up front. I can fit a 245/40-17 Ecsta MX on a 17x8 wheel up front on my '89 with the Stance setup. The Falkens or Nittos can't be that much wider in cross-section than the Kumhos (if wider at all).

Just sayin...

Edit: Just realized that there's no such thing as a 245/40-17 RT-615 or NT-01 :(

Exactely, the next size up is a 255 which will be a HUGE stretch to get on an 9" rim, in fact I don't even think the manufactures reccomend it. Next year I'm going to more than likely order a set of SSR's or Works in the "proper" size. 17x8.5 +30 and 17x9.5 +40 (I believe) and run a 255/275 stagger.

Quote:

Originally Posted by SPICcnmFD (Post 76316)
I'd go zero toe(F & R) since you street drive it primarily. Toe out makes it twitchy, especially under hard breaking, not worth the crisper turn-in IMO on a mostly street driven vehicle.

Thank you. The roads around here blow, especially the highway in some areas. With SLIGHT toe-in, I could almost let go of the wheel and let the car track itself up and down miles of interstate. O I think I'm going to try 0 toe to start.

Quote:

Originally Posted by SPICcnmFD (Post 76316)
I'd go with 1.5* negative camber front and rear to start with. It's going to eat the insides off on the street the more you put into it(well take out). The only real way to tell is set it and drive it and measure the tire temps and wear.

I'v got grease pencils, Hsa the price of thero-probes come down reasonably?

Quote:

Originally Posted by josh18_2k (Post 76359)
ok heres my recommendation. stick with your original tire size (235,255). anything wider up front is really pushing your clearance, unless you wanna run spacers and roll fenders.

No spacers, rather buy different wheels. Can't really roll the front drivers fender either.

Quote:

Originally Posted by josh18_2k (Post 76359)
Direzza Z1 Star Specs are the new hot shit around town. I don't know how their pricing compares with Azenis, but if they're close enough, go Z1's. They are much better in wet, and slightly better in dry. Wet performance is worth choosing them.

From Discounttiredirect.com

Azenis = $124/$141 = $530
Direzza = $150/$173 = $646
NT-01 = $163/$178 = $682

This car will never see the rain unless I get caught in a storm on a road trip. For the last 5 years, I haven't even had wipers on it and I closed up the nostril looking washerspryaers on the hood when I painted.

Is the dry performance really better than the Azenis though? Looks like the Azenis puts down more rubber.

Quote:

Originally Posted by josh18_2k (Post 76359)
alignment- no more than 1.5 camber in back, and at least 2.5 in front. the front needs camber to work right! my plates max at 2.5, and i need more to maximize the tire. dont worry about tire wear. drive harder if you want them to wear evenly lol
and yah, zero toe all around. with your offsets the car should be stable enough.

Excellent, thanks so much. I believe my plates max @ 3*, so hopefully if I need more than the 2.5*, I can get a little more.

Quote:

Originally Posted by SPICcnmFD (Post 76412)
:icon_tup: That's what I have on my FD and it's wears tires evenly when driving hard. On the street it eats the front insides pretty quick, which is why I suggested less up front. I'd do stock Caster setting FWIW, but that's just me.

I can only do stock caster unless I notch the tower or change the plates. Maybe the thing to do is just quick camber changes. run 1.5* on the street and bump it up on race day. Shouldn't take too long and tools will be there. The plates are marked so as long as we verify that the plates are correct while aligning it, it should be easy enough.

P71 03-11-2009 11:58 AM

Max the caster, period. Running -1.5* on the street and switching to -2.5* on a tight autocross sounds like a good idea. Most cars lose time after about -2.5* so that's the most you want to go. I like 0 toe as I run HPDE's and autocross plus I street drive my car to the locations.

Rogue_Wulff 03-11-2009 01:24 PM

As I pointed out early on, toe out does improve turn in response, but at the price of straight line stability and speed, along with increasing tire wear.
To that end, many autocrossers will dial in a bit of toe out at the event, and set it back before leaving. Autocross does not see speeds high enough for the toe out to be any real issue.
Negative camber, within reason (-1* to -3*), does not adversely affect tire wear, unless combined with toe out. Yes, driving a car on the street with too much negative camber will cause some excess wear, however a car that will see "sprited" driving more often than highway cruising will not be as prone to seeing the excessive wear.
As for caster, most street cars cannot be adjusted far enough to have any adverse effects. But racecars can be hindered by too much caster.
Of course, the tires play a role in what settings work best. Some tires like more agressive settings, while others do not.

Personally, I run a bit of toe out, within factory specs, and leave it alone. I can't get more than -1* camber due to the FB front suspension design, and the camber/toe out combo hasn't caused excessive wear. In fact, the outer edges of my tires have more wear than the inner edges. This is due to being camber limited, and hard cornering.
The car is a tad twitchy on the highway, but not enough to be a problem.
I'm also not running tires quite as sticky as the RT615, Z1, or NT-01 (yet). But, after 2 full seasons of autocross, and ~20K miles, they are still holding up well, aside from a bit of outer shoulder wear. Flipping them around and swapping sides of the car they are on, would prolly help me get a few more miles out of them in the long run. I'm hoping to upgrade from Kumho Ecsta SPT to Falken Azenias RT 615 soon though, so I haven't bothered with the side swap, since the wear isn't too bad.


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