Targa Triangle brace

greenberet said:
A reputable source of NSX knowledge shed some light on the matter.

When designing the NSX-T, the roof was cut off a coupe and a chassis reinforcement study was carried out. In the end, over 50 points of the chassis were reinforced and changes were made to parts of the internal aluminum structure. Some of those reinforcements were then built into the NSX coupes as well, making the chassis of later coupes more rigid than those of earlier coupes. It was found that the NSX-T’s triangulated rear strut tower brace was not required on those later coupes.

Regardless how rigid you make the chassis of a car, it’s going to flex a bit. When you change how much it flexes, you will also change its resonant frequency. The new resonant frequency may lead to an increase in perceived noise, vibration, or harshness (NVH). Kind of like sitting inside a drum instead of inside a bean bag. Additionally, that new resonant frequency could potentially induce an unwanted vertical vibration in the chassis that negatively impacts the tires’ contact patches with the road.

To determine whether those negative side effects crop up or not, you have to carry out tests. Some people who installed 2002+ NSX-R front chassis braces in a regular NSX removed them again because they didn’t like how they impacted the car’s feel. Other people prefer the feel of the car with those front chassis braces in place. It may be a similar matter installing a triangulated rear strut tower brace in an early coupe.

If you find that increasing your NSX’s chassis rigidity negatively impacts some aspect of NVH or roadholding, you could unbolt the chassis reinforcements again. If you have access to development facilities, you could try to dampen the new resonant frequency instead with something like Yamaha’s Performance Damper. Increasingly, car manufacturers like Toyota are not only trying to build rigid chassis but also to dampen chassis resonances to further improve “driving stability and riding comfort”. That way the car can be as tight as a drum while having almost as few resonances as a bean bag.

I haven’t heard of a Yamaha Performance Damper having been developed for the rear of an NSX’s chassis. Since I like the way the NSX-R front chassis braces changed the feel of my NSX, I may try installing a triangulated rear strut tower brace in my early coupe as well and hope it has a similar effect.
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Let us know if you do, and if you find any bad/ill effects.
 
HONDA_RJJ said:
If you didn't have to have a triangle or have to clear a Super Charger, the normal works well and is pretty easy to install.

4ae7421a.jpg
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You have an orange bar on a red car? :confused:
 
I have a 92 converted to Targa and mine has the stock targa brace mounted, so I know it is possible. Here is a pic.

IMG_0733.jpg



(FYI PIC WAS FROM THE PREVIOUS OWNER, NEON LIGHT NEAR REAR WINDOW HAS SINCE BEEN REMOVED!!! HAHA I JUST KNOW SOMEONE WILL EVENTUALLY SPOT THAT AND BASH ON IT, SO I FIGURE I WOULD DEFEND MYSELF NOW!!)
 
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well what about the 2 front bolts its just sitting there, without those bolts the brace is useless as now you have cut your coupe's chassis.

I have a coupe and I have an extra targa brace sitting around and was thinking of doing that same mod. was going to drill into the cabin and run some stainless steel bolts thru teh brace into the cabin. it would be covered by the leather top bolster ya know.
 
I have the STMPO reat strut brace and DO notice a very real difference in the flex and stiffness - ex: rear view mirror does not seem to vibrate as much, and when approach my driveway from an angle (so not to scrape chin spoiler) it just seems to stay real stiff...can't really explain, but you can feel it ....for street driving only, have had NO cons...only PROS... of course I am in a "T" with almost 90% of the driving with roof off...so effect is substantial.
 
STMPO Rear Strut Tower Brace

I just installed a STMPO rear strut tower brace on my 99 Targa. After much review and researching, I decided to go with this bar versus the one from SoS. Maybe it had more to do with cost, but I did like the "beefy" look of this bar in comparison (to the SoS one). Seemed like more value for the money?!? In any regards, this thing was a pain-in-the-you-know-what to put on!!! But Ross from STMPO provided some helpful tips! I was fearful from reading a lot of the post on a closed thread here on the forum that a lot of the users had to cut and/or modify their bars to fit. This is what I did. After removing the existing strut tower bar, you'll have to remove the plastic cover that covers up the 3rd bolt of the shock tower. There's about 5 little screws; it was pretty straightforward. You'll have to lift the trunk a bit to get to the screws in the back. Then, I loosely attached the STMPO bar to the firewall with both bolts. Then, you really do need to "jack" one side of the car up, remove the wheel on the side you are working on and I had to jump on the brake calibers to get the strut tower bolts to sink just a little so that the holes of the RSTB would align. This was done on the other side as well. All-in-all, the job will take about 1 1/2 hrs. Yup! It really wasn't as easy as it looked. I do feel that the car is more stiff than running the stock bar and it was great; otherwise, I would have felt that it was $670 gone to waste. Asians hate that!!! Ross from STMPO was easy to talk to and responded well when left a voice mail. Looking to add a bit more bars in the front, so...I would definitely looks at the STMPO line.


168.jpg
 
I have had the STMPO RTSB for quite some time and it definitely does what Ross intended it to do, stiffens up the chassis/cowl (and it looks nice too)

One thing, check your vacuum line clearance and adjust/press the lines downward or mod the bar.
#1 vacuum line may rub on it where I have placed the red circle on your picture

168wcircle.jpg
 
but your brace isnt doing anything that the original one did since your is not bolted to the firewall.

IMG_0733.jpg

- - - Updated - - -

the arrows are where the bolts should go.
 
99targa said:
I just installed a STMPO rear strut tower brace on my 99 Targa. After much review and researching, I decided to go with this bar versus the one from SoS. Maybe it had more to do with cost, but I did like the "beefy" look of this bar in comparison (to the SoS one). Seemed like more value for the money?!? In any regards, this thing was a pain-in-the-you-know-what to put on!!! But Ross from STMPO provided some helpful tips! I was fearful from reading a lot of the post on a closed thread here on the forum that a lot of the users had to cut and/or modify their bars to fit. This is what I did. After removing the existing strut tower bar, you'll have to remove the plastic cover that covers up the 3rd bolt of the shock tower. There's about 5 little screws; it was pretty straightforward. You'll have to lift the trunk a bit to get to the screws in the back. Then, I loosely attached the STMPO bar to the firewall with both bolts. Then, you really do need to "jack" one side of the car up, remove the wheel on the side you are working on and I had to jump on the brake calibers to get the strut tower bolts to sink just a little so that the holes of the RSTB would align. This was done on the other side as well. All-in-all, the job will take about 1 1/2 hrs. Yup! It really wasn't as easy as it looked. I do feel that the car is more stiff than running the stock bar and it was great; otherwise, I would have felt that it was $670 gone to waste. Asians hate that!!! Ross from STMPO was easy to talk to and responded well when left a voice mail. Looking to add a bit more bars in the front, so...I would definitely looks at the STMPO line.


View attachment 98838
Click to expand...

really curious as to why you and everyone had to go through so much trouble to install. jacking the car and taking off wheels etc. mine was pretty straight forward. i took my time so about 30 mins. unbolted the old one and bolted the new one in.
 
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I'd like the answer to this as well. I just got one and would like to know is it a one beer job...six pack or twelve pack?

I may call Ross beforehand and get his opinion...maybe the bar has changed or has a couple of variations.
 
It took me about an hour. I did jack the car up to drop the suspension on one side but you should not have to do both sides. Just make sure you do the side that you plan on dropping after doing the other side.
 
sippy2 said:
I'd like the answer to this as well. I just got one and would like to know is it a one beer job...six pack or twelve pack?

I may call Ross beforehand and get his opinion...maybe the bar has changed or has a couple of variations.
Click to expand...

It's not a hard install. You have to remove the black garnish and jack up one side to get the shock tower bolts to drop. Took me 15 minutes. And it's the best bar there is.
 
I agree. Not a hard job once you realize what you have to take off. Had the car on jacks and had my son stand on the rotor to lower the strut. Then it just fell into place. Yes, check the clearance on the vacuum lines. After 2 yrs my #1 line broke. It definitely stiffened the ride .
 
RedWings...Thanks for the advice! I do see some clearance, but a good bend here and there won't hurt!

Shawn119075....not sure what you are referring to. The bar mounts to the existing holes in the firewall.

It probably took me a long time because I'm really a first time DIYer! Hopefully the struts and springs don't take a whole day! :)
 
sorry about that I opened my mouth before thinking you have a 99 LOL thought this thread was about putting a targa on a coupe. yikes sorry
 
Just did it. It took me about 45 minutes. Removed the clamshell....in the process. I used hand tools and a hydraulic jack. Ross must have made a mod on later braces...mine has a cut out right above the lines.

It was nice to now to jack one side up...made it a snap.

TURBO2GO said:
It's not a hard install. You have to remove the black garnish and jack up one side to get the shock tower bolts to drop. Took me 15 minutes. And it's the best bar there is.
Click to expand...
 
shawn110975 said:
sorry about that I opened my mouth before thinking you have a 99 LOL thought this thread was about putting a targa on a coupe. yikes sorry
Click to expand...

It started out that way. :rolleyes:
 
Mine also has the cut-out for the vacuum lines but after 2 yrs the line still broke. I might have to check if maybe a motor mount is broken.
 
sippy2 said:
The vacuum lines referenced in redwings post #58 of this thread. My bar has a cutout on the underside...for tons of clearence.
Click to expand...

When I spoke with Ross in December I mentioned that the "notch in bar" should be moved towards the center of vehicle about an inch or so

Don't know if he has made any with such a modification, post up a picture Sippy2

There is another thread somewhere that discusses this
 
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I have the Supercharged Stmpo bar so this is a non issue as I don't even have that manifold. Just letting the CTSC guys know.... This doesn't affect you.
 

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