• Protip: Profile posts are public! Use Conversations to message other members privately. Everyone can see the content of a profile post.

relation between horsepower and sway bars

Springs do so much more than control lean... Dive and squat are under spring control only.

Yes and I said: "Springs don't physically take traction away at the tire like a sway bar (maybe if you go to 1000lb.s or something?) they simply change the body roll characteristics which is a product of the weight distribution of the car - where is most of the weight and what effect will that have under braking, turning, and accelerating?"

So I think we are on the same page but I will clarify my understanding of springs: they effect braking (dive), turning (pitch and roll), and accelerating (squat).

As far as dampers, I have a friend who holds the TTC lap record at Putnam (the track I was on in the video I posted yesterday) and I went for a ride with him for some 9/10ths laps in his AP1 S2000 - its apples to oranges to compare the handling characteristics to an NSX as the S2000 is 50/50 weight dist. from the factory but his setup consisted of OEM sway bars, Ohlins re-valved to take a very high spring rate (about what your front rate is but on both axles with a slight bias), and a large rear wing with hardtop-no splitter. That car handled absolutely incredible with him driving and I was amazed at the balance of that car. There you had a very high spring rate on both axles coiled over a very high quality damper, so I can see what you mean...perhaps I will end up re-valving the V3's? One last thing on dampers, is it true that damper adjustments are akin to tire pressure adjustments, as in they are not making a huge impact on handling like say, adding a 1" sway bar? I experimented with damper adjustments on the V3's at two different tracks and really could not pick up much difference in handling - barely noticeable. Rake on the other hand IS something I have felt have a major influence on my cars handling and I currently have 1/8" front rake. At Autobahn I started at a 1/4" and the car felt good but the rear would breakaway under momentum on corner entry on two specific turns. I consulted Coz on the phone and he recommended playing with the rake, so, I took the rear down an 1/8" and the it was like magic - more difficult to duplicate the oversteer on turn-in and if I did it was because I was simply carrying more speed into the corners now. Then I thought, lets go zero rake? That ended up making the car loose at the apex of higher speed corners so I took it back up to 1/8" and thats were it sits. I add the wing, change springs, strip more weight (I'm 3060 with me in it and 1/2 tank) and I might revisit the rake setting.

As far as sway bars, after that ride he said he likes the feel of stock sway bars on almost everything he drives. I thought about it, and decided used 91 sway bars were cheap and easy to put in, so I did it and so far I really do think its one of the best changes I've made to the car - there is more compliance and much more steering feedback up front and breakaway doesn't happen on-power out of low speed corners nearly as dramatically as with the 7/8" bar back there. Sorry if this is all starting to sound like conjecture but I am still learning and this helps me to talk with you guys.
 
Yes and I said: "Springs don't physically take traction away at the tire like a sway bar (maybe if you go to 1000lb.s or something?) they simply change the body roll characteristics which is a product of the weight distribution of the car - where is most of the weight and what effect will that have under braking, turning, and accelerating?"

So I think we are on the same page but I will clarify my understanding of springs: they effect braking (dive), turning (pitch and roll), and accelerating (squat).

As far as dampers, I have a friend who holds the TTC lap record at Putnam (the track I was on in the video I posted yesterday) and I went for a ride with him for some 9/10ths laps in his AP1 S2000 - its apples to oranges to compare the handling characteristics to an NSX as the S2000 is 50/50 weight dist. from the factory but his setup consisted of OEM sway bars, Ohlins re-valved to take a very high spring rate (about what your front rate is but on both axles with a slight bias), and a large rear wing with hardtop-no splitter. That car handled absolutely incredible with him driving and I was amazed at the balance of that car. There you had a very high spring rate on both axles coiled over a very high quality damper, so I can see what you mean...perhaps I will end up re-valving the V3's? One last thing on dampers, is it true that damper adjustments are akin to tire pressure adjustments, as in they are not making a huge impact on handling like say, adding a 1" sway bar? I experimented with damper adjustments on the V3's at two different tracks and really could not pick up much difference in handling - barely noticeable. Rake on the other hand IS something I have felt have a major influence on my cars handling and I currently have 1/8" front rake. At Autobahn I started at a 1/4" and the car felt good but the rear would breakaway under momentum on corner entry on two specific turns. I consulted Coz on the phone and he recommended playing with the rake, so, I took the rear down an 1/8" and the it was like magic - more difficult to duplicate the oversteer on turn-in and if I did it was because I was simply carrying more speed into the corners now. Then I thought, lets go zero rake? That ended up making the car loose at the apex of higher speed corners so I took it back up to 1/8" and thats were it sits. I add the wing, change springs, strip more weight (I'm 3060 with me in it and 1/2 tank) and I might revisit the rake setting.

As far as sway bars, after that ride he said he likes the feel of stock sway bars on almost everything he drives. I thought about it, and decided used 91 sway bars were cheap and easy to put in, so I did it and so far I really do think its one of the best changes I've made to the car - there is more compliance and much more steering feedback up front and breakaway doesn't happen on-power out of low speed corners nearly as dramatically as with the 7/8" bar back there. Sorry if this is all starting to sound like conjecture but I am still learning and this helps me to talk with you guys.

Nick,

You are running with 3 deg of camber upfront. One of the advantages to a big sway bar up front is keeping the tire contact patch on the road, with 3 deg you don't need as much sway or spring to do that. When I was running stock camber bushings in the front (max 1.5 deg) my front tires were rolling over and the outside left was getting eat'n alive.
 
Dal would run up to -6 camber... Specifically in the paper he wrote that he felt that although the tires heated up more on the straights, that the gain in the corners was worth it because the NSX's strong suit on the track was handling not the straights. After a compromise for straight line stability and speed and a lowering of negative camber, they returned to the -6.

I'm not suggesting anyone do any of this, I'd rather listen to Billy or one of the Jims but I think the is interesting stuff. Dal had realtime racing helping with lots of stuff.
 
Last edited:
Dal would run up to -6 camber... Specifically in the paper he wrote that he felt that although the tires heated up more on the straights, that the gain in the corners was worth it because the NSX's strong suit on the track was handling not the straights. After a compromise for straight line stability and speed and a lowering of negative camber, they returned to the -6.

I'm not suggesting anyone do any of this, I'd rather listen to Billy or one of the Jims but I think the is interesting stuff. Dal had realtime racing helping with lots of stuff.

It also depends on the tires they were running..... true racing slicks or DOT R Comps? R Comps are generally happy with 2-3 deg camber. The only real way of telling is a pyrometer and consistent lap times.

- - - Updated - - -

Dal would run up to -6 camber... Specifically in the paper he wrote that he felt that although the tires heated up more on the straights, that the gain in the corners was worth it because the NSX's strong suit on the track was handling not the straights. After a compromise for straight line stability and speed and a lowering of negative camber, they returned to the -6.

I'm not suggesting anyone do any of this, I'd rather listen to Billy or one of the Jims but I think the is interesting stuff. Dal had realtime racing helping with lots of stuff.

Dave do you have a link to the DAL archived? The website is gone.
 
Last edited:

This is brilliant, I have never read it. With just -3 camber on my car I can confirm coming straight in from 5 hot laps in a row with the probe guage, the insides are definitely hotter than the middle and outside, however the middle and outside seemed equal across the board as I eluded to in my video post. So I might actually go -4 in front next time except I am stock in the rear so -2.8 might be all I can do back there...do the toe links allow for more camber back there? I'll have to check.

He clearly must be referring to the ABS system on the NA2's when he says the ABS system is one of the most advanced on the market :)

Still puzzled on the sway bar stuff...I guess one of these days I will buy a 1" bar and try it fro a couple sessions, see what the lap timer says, sometimes changes can be faster while not "feeling" faster? For now, I'm going to keep on with the OEM "paperclips" ;-)

Billy is always right and when he says its alot more complex than just throwing a bar on or changing springs its re-assuring to me because we are all running different setups on different tires, driven in different styles, different power, etc. I will always post my setup in my vids so anyone who cares to critique or offer advice can see what I'm working with. What sort of data acquisition does it take to start having FACTS instead of feel alone to progress in car setup? Probably nothing I can afford.

- - - Updated - - -

Can you please advise how and at what points you measured the rake? Thanks

Front and rear factory jack points, on a level lift of course, then if you have KW V3's every full turn of the perch = 1/8" which should then be verified on a level lift again but if you're at the track and feel the need to make a rake change I knew I had a 1/4" rake verified on a level surface before hand and decided I would just do a full turn on each of the rears down at the time.
 
Back
Top