How to reduce flex?

Perhaps you can get a one off roll bar made that extends forwards to the 3/4 door area and backwards through the rear cabin glass to the strut towers? It most certainly will not be very comfortable. Or...fill the chassis rails with foam urethane. IIRC, Mazda did it with a few RX8s (god forbid that batman sees I brought up mazda and stinkin' rx8s) and had good results with it. Of course, that won't be easy or as plug-and-play as the alternatives mentioned previously.
 
Last edited:
I had a coupe for 5 years and now T for 5 years. I've been forever chasing the same chassis rigidity as the coupe.
I have put on so far
- Taitec front tower brace
- Dali track sways
- STMPO front chassis brace
- Type R front lower bar
- STMPO RSTB (biggest difference)

Coming soon Lovefab front upper brace and harness roll bar.

I think thats all you can do to the T top. All the mods help more with the roof off.
I had a Gallardo Sypder and that was stiff but there is flex and jiggle.
Even my LP640 coupe creaks and groans.

Our recent drive with Uehara san it seems clear the T was a request by ACURA for the american market. I dont think they put as much thought into the NSX T as opposed to the S2000 platform.
 
NSXBOX said:
I had a coupe for 5 years and now T for 5 years. I've been forever chasing the same chassis rigidity as the coupe.
I have put on so far
- Taitec front tower brace
- Dali track sways
- STMPO front chassis brace
- Type R front lower bar
- STMPO RSTB (biggest difference)

Coming soon Lovefab front upper brace and harness roll bar.

I think thats all you can do to the T top. All the mods help more with the roof off.
I had a Gallardo Sypder and that was stiff but there is flex and jiggle.
Even my LP640 coupe creaks and groans.

Our recent drive with Uehara san it seems clear the T was a request by ACURA for the american market. I dont think they put as much thought into the NSX T as opposed to the S2000 platform.
Click to expand...

I had the exact same setup as you (minus the Dali sways), trying to make my 2002 stiffer. The parts absolutely helped, but not the degree I wanted. My friend's S2000 felt more rigid. It is just a side effect of an open top car that was not designed to be so.
 
How did sway bars come into this conversation? they don't have anything to do with chassis rigidity.

- - - Updated - - -

I think from an OEM performance perspective, the Zanardi was the best NSX to come out of a Honda factory. In the US of course. We didn't get any R's. :mad:
 
cf cover2.jpg
i feel less flex with this set up in my nsx. i also have lovefab front bar and lower bar along with TaiTec front strut bar, it seem like it helping alot with stiffness. i know i got a lot of bar in my car and that will ad more weigh to the car, but car is 550 whp so ad a litter more weigh don't seem to hurt much.
sky
 
Would an X-brace in place of the targa help? maybe new brackets in the four corners of the targa with a beefy x-brace? I can't imagine the little OEM dowel pin holes could take much abuse.
 
Boostedtaco said:
Would an X-brace in place of the targa help? maybe new brackets in the four corners of the targa with a beefy x-brace? I can't imagine the little OEM dowel pin holes could take much abuse.
Click to expand...

If it was welded in then yes, but then it is no longer a targa is it? Outside of that, it still is an open top car, and will continue to act like one.
 
Caustic said:
If it was welded in then yes, but then it is no longer a targa is it? Outside of that, it still is an open top car, and will continue to act like one.
Click to expand...

I was thinking of a bolt-in brace for track use or something. I've seen x-braces for supra's and vettes.

Like this one. Not sure how much it'll improve rigidity though

994b6f49.jpg
 
Juice said:
Or you could just buy a proper NSX with a top. Seems like a lot of work to make your car into something it is not.
Click to expand...

You don't have much choice if you want a newer NSX. Besides.. for me the flex is so small with the top on it's not an issue.
 
LOL! I actually penciled a similar design several years - I may have even posted it here on Prime - but the issue to me was how to solve securing it on the NSX without really affecting the T to be put back on, and how to get a manufacturer motivated .....


Boostedtaco said:
I was thinking of a bolt-in brace for track use or something. I've seen x-braces for supra's and vettes.

Like this one. Not sure how much it'll improve rigidity though

994b6f49.jpg
Click to expand...
 
Update I've had the Lovefab upper chassis brace for 2 weekends now and taken for long drives with roof down I notice an improvement in the front.
Only have the harness bar left to go to strengthen it.
 
I must say, from an engineering standpoint I don't see how ANY brace would help eliminate or reduce cowl shake unless that brace is attaching the window frame to the B pillar frame.

The Targa car is basically held together at the floor. Anything above the frame rails are doors which have almost no additional bracing as they open, and the roof which when off, adds zero support.

Any bracing you add, you are adding to the front half or rear half of the car. And if you stiffen two halves, it certainly won't make the middle any stronger. In fact it may have the opposite effect in that now the middle absorbs MORE of the torsional forces. So unless someone comes up with a bar to tire the front half of the car to the rear half some place higher than the frame rails on the floor, I don't see how any bracing will help. I myself have "imagined" improvements many times. I am not saying braces are useless, they are good for the parts they affect. But those parts aren't the front and rear halves of a targa car.
 
Last edited:
Okay, wait... Is the NSX unitbody construction, or does it actually have a frame? I was under the impression it was unitbody (like everything else in modern times) and not built on a "proper" frame.

For example, with my convertible (98 Camaro), I bought subframe connectors for it (they connect the front "frame" to the rear axle by way of the lower control arms). This helped a lot with flex and I noticed a marked improvement on the first drive.

They bolt up (or weld in) just aft of the front wheels, and the lower control arms are fasented to them via a bolt through the underbody, the subframe connector, and the control arm.

Does the NSX already have something like this?

Also, for those with a frame of reference, how comparable is the T-top with top ON to a coupe? I would have imagined that the T-top itself might keep things quieter, but that it's not structurally substantial enough (or properly designed) to actually overcome chassis flex... ?
 
Top on reduces the flex by a huge margin. But... It's still not rigid like a coupe.

Here's no separate "frame" in the traditional sense but there are two rails that form a backbone of sorts. They are aluminum and everything else is attached to it in a unit type of construction. These points are what cages attach to. You can see it of you take the car apart. It's much thicker and stronger and square.
 
Ah, okay. I can picture it.

I've yet to buy an NSX, and have driven one coupe. Reading threads like this really make me want to go for a coupe, despite that it means I'm 99% likely to have to go the NA1 route.
 
naaman said:
Ah, okay. I can picture it.

I've yet to buy an NSX, and have driven one coupe. Reading threads like this really make me want to go for a coupe, despite that it means I'm 99% likely to have to go the NA1 route.
Click to expand...
I don't want to derail this thread but there's so much involved with an educated NA1 Coupe vs. NA2 Targa discussion. It's not only a matter of price.

Knowing your ultimate goal is so important to help you make the right decision. One of my best friends has a 98 NA2 and him and I struggle all the time when we discuss appropriate mods for each car. Limitations and benefits and quite different for each platform imo but at the end of the day you end up spending the same to build the ultimate street/track NSX.
 
Well, I have a convertible now, so having a T could be considered redundant.

Also, I want the NSX for the pure performance of it (which is somewhat ironic that the 3.2/6-speed is mostly Ts). That said, I also take the aftermarket into consideration. A lot of the mods are more readily available for the 3.0 and some require modification to fit on the Ts. The biggest downside to the 91-94, however, is the sniffer test. Still, with what I'm seeing, a 91-92 would probably be my most likely purchase, with a 94 being ideal and if I'm really lucky, that white/tan 2001 coupe that was last seen somewhere in NY if I remember correctly... Or a Zanardi :P
 
-
I'll chime in since I have a 2000 targa

Running the STMPO Rear Strut Tower Brace (RSTB) and the Front Chassis Brace (FCB)

The RSTB will change your targa, period. Find one, buy it, this is what the OEM brace should be

The FCB did tighten up the front-end, feels more "go-kart" and stiffer

I believe that LoveFab is making products that address similar concerns if you can't get the above
 

Similar threads

Chris_Lum
DIY: Alcantara Wrapped Seat Belt Guides | 1991-2005
Replies
0
Views
37
Chris_Lum
Chris_Lum
J
Turbo rebuild
Replies
4
Views
1K
Valhalla
Valhalla
asylum
Tips on suspension settings
Replies
5
Views
1K
Track Addict
Track Addict
TANTO
CLUTCH/BRAKE LINE OE MATERIAL
Replies
2
Views
332
Honcho
Honcho
R
How to remove panel under steering column
Replies
11
Views
370
rustymufflers
R
Back
Top