Rear beam bushing question

[TURBO2GO]

I bought a set of rear beam bushings from tiDave and handed them to my shop. They called me and said there are 4, and why would I replace only two on the A arm
(The rear two). They said it makes no sense, that the front ones on the arm should be replaced too.

I don't particularly know what these are even to, now I'm guessing they attach the rear wishbones to the center beam? I need to get under there and look. But anyway, if there are 4, why do we replace only two?

 

[RYU]

http://ojas.net/nsx/mirror/dal#Compliance

 

[docjohn]

If Dave has not read that dal white paper yet he better start....:wink:

 

[TURBO2GO]

Thanks Ryu I keep forgetting about that page. Man that is a lot of good info.

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So basically he is saying for racing you should replace them all.

 

[jaffaz32]

I have these to install also and i wonder how you install them? Ok that does sound a silly question, let me explain.

The hole is not centered and to the side so this means it can be rotated 360 degrees for adjustibility how do you know what position to install it for the best setup? because i assume once it's installed in a particular position it's very difficult to change.

This is also the same for the Comptech front ones.

 

[illwillem]

I've been on a quest of sorts to replace all the bushings on my NSX I was surprised that there is only a few places that make any bushings whatsoever and even fewer still that make the 'less obvious' ones. Seems the bushings on the bar are no problem but there isnt any support for the rear A arms. I sent all my knuckles out to Steve Ghent to replace the ball joints and we got on topic of replacements for the rear upper A arm bushings too. He said that he'd done some in the past for his race car and the FXMD NSX and would be able to do them again. He didn't have the mono ball sizes on hand but it wouldn't be a problem to get the measurements off of the A arms I would send in. He touched on price but was just ball-parking numbers, about the same as the ball joints he does. I think I remember seeing that TiDave had done some too.

Steves busniss card: http://www.nsxprime.com/wiki/Ball_Joints calling is better than email I found out.

TiDaves: http://www.nsxprime.com/forum/showt...ion-all-pivots!?highlight=full+non+compliance

 

[TURBO2GO]

I have these to install also and i wonder how you install them? Ok that does sound a silly question, let me explain.

The hole is not centered and to the side so this means it can be rotated 360 degrees for adjustibility how do you know what position to install it for the best setup? because i assume once it's installed in a particular position it's very difficult to change.

This is also the same for the Comptech front ones.

With the factory bushings, my minimum negative camber with the car lowered was 3. So I installed them to get LESS if I wanted to (I actually run -3) when the shop asked. But now, I am maxing out at 2.8. Which means I went too far the wrong way and have to turn them back. This was a costly mistake, but I was driving down the highway and made a quick call to ti Dave and he said "go less not more". So I can't tell you exactly where they should go yet, but probably can once it is redone. I believe they can now be turned without removing the beam and bushings again. That's what Dave said. I have to give him another call. Just be careful and try to get them right the first time.

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I've been on a quest of sorts to replace all the bushings on my NSX I was surprised that there is only a few places that make any bushings whatsoever and even fewer still that make the 'less obvious' ones. Seems the bushings on the bar are no problem but there isnt any support for the rear A arms. I sent all my knuckles out to Steve Ghent to replace the ball joints and we got on topic of replacements for the rear upper A arm bushings too. He said that he'd done some in the past for his race car and the FXMD NSX and would be able to do them again. He didn't have the mono ball sizes on hand but it wouldn't be a problem to get the measurements off of the A arms I would send in. He touched on price but was just ball-parking numbers, about the same as the ball joints he does. I think I remember seeing that TiDave had done some too.

Steves busniss card: http://www.nsxprime.com/wiki/Ball_Joints calling is better than email I found out.

TiDaves: http://www.nsxprime.com/forum/showt...ion-all-pivots!?highlight=full+non+compliance

In the DAL Motorsports article Ryu linked above, they replaced EVERY BUSHING, on the NSX, and it says something like "driving a an NSX with no compliance parts is amazing". I am still not quite sure why we replace two and not the other two from a technical perspective... But apparently when you go full race, you do. Perhaps tiDave who is very knowledgable on this can will chime in.

 

[RYU]

$0.02...

I've driven a car with all poly and steel bushings when it came with rubber bushings from the factory. It may be fantastic on the track but it was god awful on the road. Noisy, hard... you name it... I would hate for my NSX to be that way. I'm just not as good as you guys in my driving skills to make it worth it. I can see why someone like Willem would find that a huge benefit wherein the rubber bushings are holding him back. You can drive man!

It's a compromise and some have more tolerance for certain things than other things.

 

[TURBO2GO]

Well I did the rear beam bushings, toe links, sway bar links (can someone tell me what these do? LOL) and front clamps and on the street I feel NO difference in terms of noise or harshness.

 

[RYU]

Well I did the rear beam bushings, toe links, sway bar links (can someone tell me what these do? LOL) and front clamps and on the street I feel NO difference in terms of noise or harshness.

Go more and change more and let us know if you're hating your car for NVH or not

God.. pillow ball mounts especially are awful in the noise department. "Pillow" is a huge misnomer

 

[TURBO2GO]

I have those too. pillow ball... LOL

 

[titaniumdave]

Hi Guys,
If you have my beam bearings, it's easy to change the set up for increased or decreased camber. The offset hole is in the 'step-down' bushings, they can be rotated while installed on your car. I do this by removing the lower A-arm bolt (which has the camber cams) from the beam bearing, put the bolt back in the bushing hole and tighten it. Then you can use the bolt head to rotate the bushing into any position you want, center and pointed down if you want the same adjustment as stock(I make concentric/no offset bushings too), inward if you want less camber or out ward if you want more.

I offer bearings for all location on the NSX suspension. I use Teflon lined, hardened stainless steel bearings and have not notice an appreciable increase in noise or harshness of the ride. I know lower quality bearings have a tendency to sound like metal on metal, but I think the NHBB bearings I use really keep thinks quiet and smooth.

The reason most people only change the beam bushings and toe links on the NSX is these are the most heavily loaded points and there is some dynamic toe change as the suspension loads in corners. This is the biggest bang for the buck as far as suspension up grades. I have a front lower, inner bearing set done too, it will allow the same camber changes plus remove the rubber bushing which greatly increases turn-in crispness and steering sensitivity. I hope to have the first batch back from CNC by the end of the month.

 

[illwillem]

Dave when you say the 'front lower inner bearing set' are you still talking about the front of the rear A arm or the front of the car in-board uprights. (same as the ones that I bought from you last month).

Another question- I got A rear beam from you about a year ago that I put it in myself. Would this one also have the adjustable camber in the step down bushing that you described above?

 

[jaffaz32]

With the factory bushings, my minimum negative camber with the car lowered was 3. So I installed them to get LESS if I wanted to (I actually run -3) when the shop asked. But now, I am maxing out at 2.8. Which means I went too far the wrong way and have to turn them back. This was a costly mistake, but I was driving down the highway and made a quick call to ti Dave and he said "go less not more". So I can't tell you exactly where they should go yet, but probably can once it is redone. I believe they can now be turned without removing the beam and bushings again. That's what Dave said. I have to give him another call. Just be careful and try to get them right the first time.

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In the DAL Motorsports article Ryu linked above, they replaced EVERY BUSHING, on the NSX, and it says something like "driving a an NSX with no compliance parts is amazing". I am still not quite sure why we replace two and not the other two from a technical perspective... But apparently when you go full race, you do. Perhaps tiDave who is very knowledgable on this can will chime in.

Thanks that's very helpful.

because i'm still a novice at track and only do a few a year you guys recommended not to go too extreme on the negative camber so maybe i should run them in the oem position as the oem position should allow enough adjustment, the car will be lowered so maybe ever so slightly inwards.

 

[titaniumdave]

Willem,
The 'front lower inner bearing set' is the set you bought last month-for the front of the car.

I send out my beam bearings set up in the 'least negative camber' setting since most cars that have been lowered have too much negative camber. I had my car at -2.6 degrees with R888 or NT-01 tires and it worked well for me, any more and I would lose traction on the rear end. This was with the car 40mm lowered,~500lb rear springs and 3 way JRZ coil-overs and OSG diff, all have an effect on how the car rolls and the tire contact patch.