Recommended Alignment Settings

[Honcho]

Experts please chime in with respect to ideal settings (ride height, toe, caster, camber, etc).

My Setup:

BCR Coilovers/Swift Springs 10 F / 8 R
RM Racing Sways 19.05mm F and R (urethane bushings)
OEM 91 Brakes
2002+ Wheels with 215/40/17 and 255/40/17 tires
Stock toe links and rear beam bushings
Stock compliance pivot

 

[nsxalot]

This was given to me by a NSX race team for my everday/track NSX.

Front Camber: 1 Degree neg and rear camber to 1.2 degree neg. Set rest to spec

Lance

 

[nsxtasy]

Experts please chime in with respect to ideal settings (ride height, toe, caster, camber, etc).

Ideal for what? What are your priorities among factors like handling feel, cornering potential, tire treadlife, etc? You might choose different settings for a track-only car from those for a daily driver.

 

[arista5]

Ideal for what? What are your priorities among factors like handling feel, cornering potential, tire treadlife, etc? You might choose different settings for a track-only car from those for a daily driver.

Will be getting an alignment soon so I will ask for me an try not to thread jack.

I don't use it daily but what would be a good street alignment with some consideration to occasional spirited driving. My last car had about 8-10k on the tires and looked new.

 

[nsxtasy]

I don't use it daily but what would be a good street alignment with some consideration to occasional spirited driving. My last car had about 8-10k on the tires and looked new.

I think the stock alignment settings (with the revised 4 mm rear toe) work fine for what you describe.

I went slightly more aggressive with mine, going with the original 6 mm rear toe recommendation (and making the camber at the negative end of the recommended range), but I was using it on the racetrack much of the time.

 

[RYU]

You posted in the track section so i'm assuming you want track settings

Some good links here
http://www.nsxprime.com/forum/showpost.php?p=1569968&postcount=15

 

[Honcho]

80% Street 20% Track
Figure 5 track days per year. I am looking for stable straight line and responsive turn-in without feeling too darty. Also, because I still have the squishy OEM links and bushings, I'd like to do as much as I can with the alignment settings to mitigate any snap oversteer tendencies and/or sudden unloading of suspension energy. I am willing to sacrifice some lap time at the track for safety and stability.

 

[nsxtasy]

80% Street 20% Track
Figure 5 track days per year. I am looking for stable straight line and responsive turn-in without feeling too darty. Also, because I still have the squishy OEM links and bushings, I'd like to do as much as I can with the alignment settings to mitigate any snap oversteer tendencies and/or sudden unloading of suspension energy. I am willing to sacrifice some lap time at the track for safety and stability.

The total rear toe has a big role in this. The originally recommended 6 mm increased the responsiveness but at the increased risk of the dartiness and snap oversteer tendencies you mention. The reduced 4 mm was intended to increase tire treadlife and also reduces those risks, at the expense of a slight reduction in responsiveness. Those more interested in treadlife than responsiveness may want to reduce the toe even further, to 2 mm or less.

Based on what you've posted, I'd suggest going with the 4 mm rear toe.

Note that alignment is something you can change any time you want, so just pick a setting and try it out. If you're not happy with it, you can always change it.

 

[RYU]

Ken, what are your thoughts on front toe out? Also, thoughts about compensating for 17/17 or 17/18 more modern tires if any compensation is required.

For a neutral car what's your recommended rake to start off with. I increased my rake to be higher in the rear by 1/2" and it was a mistake. Tendency to oversteer was more pronounced.

 

[nsxtasy]

I've never heard anyone recommend anything other than the stock recommendations for front toe or rake, not even for track use. I'm not saying variations from stock aren't possible or desirable, but they're not very common.

Changing wheel diameter shouldn't have any effect on what works best.

 

[Honcho]

Following up, should I have the alignment and corner balancing done with me in the car? The wiki says driver weight can change camber by as much as 0.3 degrees on the driver rear and can also change toe. I am mostly by myself when I drive my NSX, even on the street (my wife gets motion sick lol), so it would seem this is the best way to go?

We should set the ride heights first and then align, correct? Does anyone know why there is a range in the stock height specs for an empty car? Is the low number with full fuel and the high number dry? When setting the corner heights, should I first set to Shad's recommended 4" front and 4.5" rear at the jack points and then adjust for corner balance with me in the car? I just want to make sure we do this the right way the first time.

 

[g3driver]

my settings:
front toe -1/16
rear toe +1/16

front camber -1.25
Rear -1.85

Front caster 9.0 degrees

I really love the way the car turns in and drives with this. I also corner balance and do my own alignment with scales and strings! Its a 4 hour job but I have have not found a shop that can do it better than me. If you are in the LA area would love to help you out.

 

[RYU]

my settings:
front toe -1/16
rear toe +1/16

front camber -1.25
Rear -1.85

Front caster 9.0 degrees

I really love the way the car turns in and drives with this. I also corner balance and do my own alignment with scales and strings! Its a 4 hour job but I have have not found a shop that can do it better than me. If you are in the LA area would love to help you out.

It's a date!?! :biggrin:

Having the scales is awesome. I have not wanted to pay for a corner balance because my setup seems to change monthly these days.

 

[e.pie]

80% Street 20% Track
Figure 5 track days per year. I am looking for stable straight line and responsive turn-in without feeling too darty. Also, because I still have the squishy OEM links and bushings, I'd like to do as much as I can with the alignment settings to mitigate any snap oversteer tendencies and/or sudden unloading of suspension energy. I am willing to sacrifice some lap time at the track for safety and stability.

I have the Type-S alignment on my car.

Most alignment machines should have the specs in them, I know for sure the Acura dealership in Colorado Springs does.

 

[HIJACKER]

I started a very similar thread a while back, search for threads started by me in this section and you will see a reply from Billy. I've used those settings and I've been VERY happy.

 

[sparky]

The reduced 4 mm was intended to increase tire treadlife and also reduces those risks ...

Less toe = less snap oversteer tendencies?

That's intriguing yet counter intuitive for me. Can you explain how this happens?

 

[CL65 Captain]

Less toe = less snap oversteer tendencies?

That's intriguing yet counter intuitive for me. Can you explain how this happens?

False. Less toe in on the rear increases snap oversteer. In fact a toe out rear would be down right dangerous to drive. Zero toe while improving tire life would not be good to push hard. As cornering forces increase the rear tire actually toes out, so if you start with zero you are going to end up with toe out and the car will oversteer badly.

There is an earlier thread where Shad said they don't relax rear toe even with the non-comp stuff.

On a purely street car, yes you can reduce toe to prolong tires, but I would leave a little toe in, as I said zero toe will lead to toe out under load.


sent from my crappy cell phone.

 

[Honcho]

False. Less toe in on the rear increases snap oversteer. In fact a toe out rear would be down right dangerous to drive. Zero toe while improving tire life would not be good to push hard. As cornering forces increase the rear tire actually toes out, so if you start with zero you are going to end up with toe out and the car will oversteer badly.

There is an earlier thread where Shad said they don't relax rear toe even with the non-comp stuff.

On a purely street car, yes you can reduce toe to prolong tires, but I would leave a little toe in, as I said zero toe will lead to toe out under load.


sent from my crappy cell phone.

Agreed and confirmed. I checked the wiki on alignment and it was clear that the 6mm original 1991 rear toe setting was intended to make the car more stable because of things like the rubber bushings and end links. I think Ken had it backwards. Anyway, I am going with 6mm rear and the rest per the 1991 spec.

 

[Honcho]

As for process, is this right?

Empty Car --> Set height at jack points 4" F / 4.5" R
Honcho gets in car --> Corner balance
Honcho stays in car --> Align to 1991 specs including 6mm rear toe

 

[RYU]

YMMV but .5" rake was too much for me. I'll be adjusting for 0.25".

Is that how much the NSXR has?

 

[Mac Attack]

In fact a toe out rear would be down right dangerous to drive.

I used to set up rear toe out when autocrossing. Helps steer the car when on three wheels. But definitely not for the street!

 

[Honcho]

YMMV but .5" rake was too much for me. I'll be adjusting for 0.25".

Is that how much the NSXR has?

Visually, or performance-wise? 4/4.5 was Shad's recommended rake setting.

 

[RYU]

Visually, or performance-wise? 4/4.5 was Shad's recommended rake setting.

Performance wise. I actually like the look of a 1/2" rake

I was able to dial out the oversteer though with my front dampers at almost full firm and my rears at full soft. I just wish I had more adjustment. If I set it at 1/4" rake I suspect I'll be closer to neutral with my 9k/11k springs. I could leave it at 1/2" rake and swap springs to 11k/9k which i'm considering heavily or get a thicker front sway bar. Coz runs his rake at 1/4-3/8" I believe.

At this point your overall setup, tire pressures, sway bars, dampers, springs make the difference between a 1/4-1/2" rake a moot point. You'll be at a point where you need to start fine tuning for your own setup and your own driving style. $0.02.

 

[nsxtasy]

The total rear toe has a big role in this. The originally recommended 6 mm increased the responsiveness but at the increased risk of the dartiness and snap oversteer tendencies you mention. The reduced 4 mm was intended to increase tire treadlife and also reduces those risks, at the expense of a slight reduction in responsiveness.

Less toe = less snap oversteer tendencies?

That's intriguing yet counter intuitive for me. Can you explain how this happens?

I don't know exactly why, but this is exactly what I was told within the past year by the person at Techline (Acura U.S. HQ) who has been tracking all NSX problems since the car was introduced in 1990. He's more familiar with the NSX's technology than anyone else in the country.

 

[LJSB]

Following up, should I have the alignment and corner balancing done with me in the car? The wiki says driver weight can change camber by as much as 0.3 degrees on the driver rear and can also change toe. I am mostly by myself when I drive my NSX, even on the street (my wife gets motion sick lol), so it would seem this is the best way to go?

We should set the ride heights first and then align, correct? Does anyone know why there is a range in the stock height specs for an empty car? Is the low number with full fuel and the high number dry? When setting the corner heights, should I first set to Shad's recommended 4" front and 4.5" rear at the jack points and then adjust for corner balance with me in the car? I just want to make sure we do this the right way the first time.

I use the information in the NSX service manuals regarding ride height. The suggest measuring points are center of front control arm bolt and center of rear toe am bolt to perfect level rack surface. Using fender to tire height or jack points makes no sense to me. You're aligning the suspension geometry so measure the suspension height not the body or body panel height.

Measuring by the wheel opening to tire or jack point to ground for alignment is like measuring the tire pressure by looks or pressing on them with your fingers. Not very accurate but it tells you something I guess.

Roughly, the range given in the NSX service manuals is 1.5 to 1.9 inches difference from front to rear rake at the measuring points the manuals show.

How this translates to the body rake measuring from the jack points I really have no idea but I know it's not going to be the same. Probably significantly less, F/R but again, it's just not a very accurate way to measure.