body-roll analysis

[R13]

My normal autocross car (MR2 Turbo) was out of commission this weekend, so I took to opportunity to get to know my NSX a little better by dodging a few cones.

Here's a video from in the car (sorry about the music over top, the camera mic was on the blink so you are only not-hearing static).

http://videos.streetfire.net/video/NSX-Autocross_640032.htm

Nothing felt too wierd from inside the car, at least not after I remembered to turn off the TCS (MR2 doesn't have TCS to turn off so I didn't think about it until it cut throttle on me as I turned to go up the hill and got on the gas). I am just curious if the level of body roll in this picture is "normal" for a car on stock suspension. The car was on street tires (HTR-Zs) and I did have a passenger, but it just looks worse than it felt.

 

[stuntman]

Looks like you were having fun!

Add me on streetfire: http://members.streetfire.net/profile/BillyJohnson.htm

 

[R13]

Cool, I'll have to browse streetfire a little more thoroughly after work today.

Yeah it was fun. Really quick and easy way to figure out what the car wants to to at the limit at a relatively slow speed. That said, I kept thinking of how much quicker it would be with some r-comps, konis, and a fat front bar

The point of course was to have a little fun and learn the car. I had an S2000 CR running in the same class, so not much chance of winning unless he coned away every run (he didn't, but I got within a second and a half while carrying a passenger).

 

[CL65 Captain]

Love the "porn music" on the video. :biggrin:

 

[R13]

I always thought of it as surf music, but I could easily understand that interpretation...in a '70s sort of way

So, since I know that the springs determine the absolute magnitude of roll, are they just that soft, or could it be leaning over like that because the shocks are hosed and it is rolling at a greater rate than it should?

I don't feel the car "bounce" too much over bumps, but my basis for comparison right now are the koni yellows on my MR2...

 

[stuntman]

Looks fine to me - like stock.

Yes spring dictates the amount of roll, damper resists (slows) the roll.

You can change the shocks to stiffer ones which will make the car 'feel' like it's rolling less, but will eventually reach the same peak amount of roll.

Nothing looks out of the ordinary. Just figure out what you want out of the car.

 

[R13]

Looks fine to me - like stock.

Yes spring dictates the amount of roll, damper resists (slows) the roll.

You can change the shocks to stiffer ones which will make the car 'feel' like it's rolling less, but will eventually reach the same peak amount of roll.

Nothing looks out of the ordinary. Just figure out what you want out of the car.

Thanks for the response. I have learned quite a bit about the car in the 5 months I have owned it, but I have the good sense to ask for experienced opinions where I am still unsure.

I am satisified with the cars road manners for now. Once I have my other car back together and I have time to tinker, I may look at some spring/shock/bar combos for a moderate increase in roll stiffness. I won't be shooting for pure track setup off the bat though. At this point I have a feeling I would still be holding the car back, rather than the other way around.

BTW, sent you an invite/request thing on SF. If you've got any, it'd be cool to see some videos of that 510 along side the Factor X car-pron.

 

[stuntman]

BTW, sent you an invite/request thing on SF. If you've got any, it'd be cool to see some videos of that 510 along side the Factor X car-pron.

I added you.

I posted all my videos on another thread but here's a post with all of them (their's a few 510 videos in there):

Kind of off topic but here you go:

My buddy then me tracking his S2000 to a local track record (Streets of Willow) - I went second (2:07 in the video-on)
http://www.youtube.com/watch?v=I29RfACVyZ8
(NSFW: F-bomb at 3:52 -end of video)

Factor X FX750 - 2008 Super Lap Battle - Long Beach Grand Prix (overall win):
http://www.youtube.com/watch?v=PMIi7sJo3B8&feature=related

Riceboy TV coverage of the SLB - Factor X FX750 overall win
http://videos.streetfire.net/video/08-Long-Beach-Grand-Prix_162474.htm

Grand Am Koni Challenge ST race winner 2007 - Laguna Seca (Kensai/Compass360 Racing Acura TSX)
http://video.google.com/videoplay?docid=-5979488650042932823

Factor X FX750 at Buttonwillow (first outing in 2007):
http://www.youtube.com/watch?v=pLwa1HXKDsI

Dsport coverage of the Factor X FX500 (interview & In-car 2007):
http://www.youtube.com/watch?v=5lG2liyjKd4&feature=channel_page

1972 Datsun 510 (2007 Redline Time Attack 3rd Place - RWD - 1:38.5):
http://www.youtube.com/watch?v=cqG8n-dqrQ0&feature=channel_page

Factor X FX500 - Buttonwillow (Early 2007)
http://www.youtube.com/watch?v=r5UTrUxBOfU&feature=channel_page

Factor X FX500 - Buttonwillow (with a passenger, hot laps - Early 2007)
http://www.youtube.com/watch?v=BC6h...file&friendid=2790503&feature=player_embedded

Wow, just found this: Me and my friend screwing around like idiots drifting S2000s (2005ish?)
http://media.putfile.com/Stuntman--bmwretard

Redline Time Attack Promo Video - Focus Auto Sales R34 GTR for the Livesockets Battle:
http://videos.streetfire.net/video/2009-Redline-Time-Attack_635123.htm

And you can't forget the video of me tracking a SEMI-TRUCK in my sig below:
http://www.youtube.com/watch?v=Huq3ba2D0Mg


Here's 3 more videos that my buddy just posted of me in the Factor X FX750 for the Super Lap Battle Time Attack, as well as me piloting the M-WorkZ TT 350Z:


Factor X FX750 NSX (1:47.9):
http://www.youtube.com/watch?v=tJhLpFjSIDo&feature=channel_page

M-WorkZ Twin Turbo 350Z (1:48.4):
http://www.youtube.com/watch?v=Jy_xla-f75E&feature=channel_page

M-WorkZ Twin Turbo 350Z (1:50.3 - CRAZY qualifying lap, insane dust cloud):
http://www.youtube.com/watch?v=QpB6dsfxttY&feature=channel_page


Here's the video the 510 drifting:
http://www.youtube.com/watch?v=SDzexVIjR9g&feature=channel


Ok I found a video of me drifting from the 2007 Sport Compact Car Ultimate Street Car Challenge in a Twin Turbo G35.

I also did the road-course part of the competition, but here is my crappy drifting in a small parking lot (30 seconds to do whatever, not enough room to carry any real speed, and its not a track):

http://www.sportcompactcarweb.com/videos/6201562/2007-uscc-2005-infiniti-g35-video/index.html

And I just found the 2008 SCC USCC with me in a Red Mazda 3 and a Blue Nissan 350Z Twin Turbo. This year they did the "Gross Display of Horsepower" in a different location that was much wider and allowed for higher speed = more smoke:

http://www.sportcompactcarweb.com/v...-gross-display-of-horsepower-video/index.html

 

[ZF Clubsport]

The thing is, you had the distinct advantage of having the coolest passenger in all of recorded history riding shotgun -- right there in your car! Words have not yet been invented to describe the awesomeness of the passenger you had that day :biggrin:.

On a more serious note, it's true that a lot of weight is over the rear suspension, but it seems that a thicker rear antisway bar would also provide a flatter cornering effect, plus some poly bushings.

Nice vid too, I'm glad you put music over our discussion of the diabolical practice of throwing small-blocks into cars that aren't meant to house them.

Here is the link I posted in reference to that weekend on the Legend forum:

http://www.acura-legend.com/vbulletin/f104/cars-coffee-knoxville-tn-3-7-09-a-135574/

 

[R13]

The thing is, you had the distinct advantage of having the coolest passenger in all of recorded history riding shotgun -- right there in your car! Words have not yet been invented to describe the awesomeness of the passenger you had that day :biggrin:.

On a more serious note, it's true that a lot of weight is over the rear suspension, but it seems that a thicker rear antisway bar would also provide a flatter cornering effect, plus some poly bushings.

Nice vid too, I'm glad you put music over our discussion of the diabolical practice of throwing small-blocks into cars that aren't meant to house them.

Here is the link I posted in reference to that weekend on the Legend forum:

http://www.acura-legend.com/vbulletin/f104/cars-coffee-knoxville-tn-3-7-09-a-135574/

Thanks for the nod on the legend boards, and for pointing out the lack of a "TCS off" light before the 3rd run, the car was a lot more managable after that.

I don't think I'd do a rear bar unless I also did a larger front bar. Otherwise you run the risk of picking up a rear tire (assuming stock springs, which are another issue unto themselves). I was having to keep a close eye, figuratively speaking, on the rear of the car as it was. Rotating the car was not a problem I encountered :biggrin:

I think the problem is that I am used to this for autocross:

Which has a huge front bar, koni yellows, and V710s (not to mention a shorter wheel-base and gearing).

 

[ZF Clubsport]

^ Ah, true. Similar mods on your X would make a difference. Well I did appreciate the chance to ride shotgun, I learned quite a bit about those cars from the runs we made.

 

[R13]

Well I did appreciate the chance to ride shotgun, I learned quite a bit about those cars from the runs we made.

No problem at all. You should jump in the MR2 with me as well later this season so you can see what I'm talking about. I should have the engine back in by tuesday, and hopefully will have it fully running by next weekend. I don't think I will make the Walter State event on the 22nd due to a once-a-month work commitment, but I will be at pretty much every event from then on.

 

[ZF Clubsport]

Oh yeah, I'm sure the MR2 is a different animal altogether. We'll be out of town on the 22nd also, so hopefully after that we'll be ready for more. Once the MR2 is up and around (if you need an extra hand, let me know), what are plans for the X?

 

[R13]

Oh yeah, I'm sure the MR2 is a different animal altogether. We'll be out of town on the 22nd also, so hopefully after that we'll be ready for more. Once the MR2 is up and around (if you need an extra hand, let me know), what are plans for the X?

Once I have the MR2 healthy and ready for a bit of DD duty in addition to the fun stuff, I have the following planned for the NSX:

-pull front bumper and re-install correctly (rubber "gasket" is not through-bolted as it should be)
-use opportunity to fix/replace damaged AC lines
-replace corroded fixtures/fasteners under front bumper
-install larger front 'bar while I'm at it
-remove ghetto-installed K20 useless radar detector
-un-fark the wiring that I suspect was farked as a result of afore-mentioned radar detector installation
-window fix-it thingies & lube
-02+ abs update (if money permits)
-rebuild brake calipers
-SS brake lines
-brake fluid flush with Motul RBF600 (just in case)
-inspect suspension bushings for cracks/wear
-pull seats and thoroughly clean/deodorize interior (it's not funky now, but who knows what's there after 200+k miles...)
-slightly larger wheels
-shocks/springs if I think it's necessary at this point
-headers/exhaust

Once all this stuff has been sorted (probably over the course of ~6months), then I'll see where I want to go with it.