quicker steering ratio??

Peter,

I think you did it. That is a great solution! I just priced a new PS rack and the dealer wants $5,100 for it, but $900 for a manual. Modified, the price would be outrageous and the number of potential buyers way down if someone wabnted a new rack. We all want a quicker ratio and the arm idea sounds perfect.

Go for it, I'll buy it. Sounds like less cash to invest to get it off the ground as well.

Different ratios would also be possible and that would allow people to taylor their requirements or alter the system if they want a different ratio.

Variable ratio would not be possible, would it?

Tytus
 
I have just a couple of thoughts on this.

The $1900 doesn't sound right for a steering rack. Especially when the Toyota one is $300. If we can't put a low-tech steering rack together for, say, double the cost of one for a Toyota, then maybe this isn't the right way to go about this.

...QUOTE]

I'd have to disagree with this. Make 1 and the price is $10,000. Make 1000 and the price is $300. We know which end of the scale the NSX is on...

My prior referenced STI quick rack is $2300 Canadian new $1200 rebuilt which is like $5k US. The ratio is 11.5:1 (which they say requires 100% concentration :)
 
I just bought a 2004 NSX and have the same complaint about the steering as many other's have indicated. I had an MR2 Turbo which I beleive had an even slower stock steering ratio but it felt much better and quicker in a hairpin situation than the NSX. It may be the smaller wheel circumference.

I am very interested in a quiker rack but it must be powered. I have no interest in going to a manual set up. Considering this is the cars' most critical short coming, I would think that lots of owners would do this modification if it were available. Considering there are possibly over 18,000 running NSXs world wide, any fraction of that number is the potential market. I personnaly would be interested in a new set up since my car has only 6,500 miles and am probably in the minority but I would be willing to pay extra to have a new electric rack converted.

The steering is the second pleasure center of the NSX after the excellerator, I'm sure every owner would want the conversion if not immediately then after it has hit the market and everyone raves about it.

PS is a must, except for the track guys, and most owners that don't have PS now but could get it along with a quicker ratio would do it, if it were available.

Put me down for a PS rack, anytime you are ready to put it together.

Tytus
NSXs rack is a littles quicker (not by a whole lot) than my MR2Turbo...

Non ps is perfectly fine once your moving faster than 2mph (even at high speeds on a track) imo...
 
I would agree that a revised rack and pinion would be the best solution, but a steering ratio quickener might be quicker and cheaper if the Quafe thing falls through.

http://www.stockcarproducts.com/steer4.htm
Yes I looked at this one. But I don’t see any space in our NSXes to put it in. without chopping things. Pity. (if anyone see it otherwise, please comment).

I have just a couple of thoughts on this.

The $1900 doesn't sound right for a steering rack. Especially when the Toyota one is $300. If we can't put a low-tech steering rack together for, say, double the cost of one for a Toyota, then maybe this isn't the right way to go about this.

I mean, if a brand new rack at full retail price is $700 to $1000, how does a rebuilt one get up to $1900? It seems that starting with brand new you could beat the $1900 price.….
I'd have to disagree with this. Make 1 and the price is $10,000. Make 1000 and the price is $300. We know which end of the scale the NSX is on...

My prior referenced STI quick rack is $2300 Canadian new $1200 rebuilt which is like $5k US. The ratio is 11.5:1 (which they say requires 100% concentration :)

Exactly.

Variable ratio would not be possible, would it?
Tytus
This solution (shorter arms) would not give variable ratio. If your original rack is variable ratio (is a PS NSX variable?) then the variable characteristics would remain, it would just be quicker.

A completely new rack (Manual) would be possible to make variable, but Quaife do not have the tools to do it.
The teeth on the rack are not all the same size and angle. See picture below for an example of how a variable ratio rack’s teeth are.
variable rack.jpg
The teeth on a non-variable rack are identical to one another, unlike the teeth in the above picture.

So anyway, my next step is to start asking around here to find a used second hand upright.
Then I will digitise it into my 3D programme.
Then I will design a new arm.
Actually the arm is no problem, it’s the mounting point that will require some thinking.
I already have thought of a system that will allow maximum ease of making the arms. But I have to see it in the computer before I can be sure it will work.
A FEA test has to be done too.

And the last step would be to cut the existing arm off and machine the new mounting surfaces.

here are the uprights.
nsx uprights.jpg
Notice the inserts. I don’t think making eccentric inserts would bring the centre point closer enough to the kin-pin axis to achieve noticeably quicker steering. So the arms need to be shorter…
Unfortunately.
Peter
 
Unfortunately Tytus a quicker power steering rack is not going to be made because I don’t have the funds to re-engineer all the motors and sensors and ECU in the PS rack. I would guess nobody will do it.

The manual rack is the one that will be made, if any.

Sorry Tytus. I too would like a power steering quick rack (I'm getting old I guess).

The only way you are going to get a quicker steering rack effect with the NSX power steering is if somebody makes a kit for putting slightly shorter steering arms onto the upright.
This would then make the manual quick rack redundant and a waste of money/time. My investment in a manual quick rack would be wasted.

So I suggest this:
Could somebody machine the steering arm off an upright (leaving a nice big flat surface) and bolt on a slightly shorter arm? The arm would be steel. Two bolts is enough to fix it to the upright, or one bolt and an existing hub bolt.

This would work for power steering and manual steering, RHD and LHD too, as the uprights are the same. This one kit would solve everybody’s problem for all types of NSXes around the world.
Different arms could be economically made for people who wanted 2.5 turns lock to lock, or 2.8 or whatever they wanted.
And an arm could be made the stock length too, for those who wanted a sort of reversibility.

If somebody would send an upright to me, I would do it.
I now sort of prefer this method, unless somebody can tell me why it is not a good idea. The small difference in the length of the arm would not affect suspension geometry. Electrolysis should not be a problem. Others?

Shall I do this?

Please feel free to give me any feedback. How many NSX owners would want to buy this?
Again, it doesn't matter if you have Power Steering, Manual steering, Left Hand Drive or RHD, a circuit racer or a canyon cruiser or if you are a grand dad, any year NSX, it is all the same kit.
Peter
So how would this shorter arm quicken the steering? Wouldn't it just add toe-out?
 
So how would this shorter arm quicken the steering? Wouldn't it just add toe-out?

Think of it the opposite... if you extended the arm by one foot. The wheel would barely turn at all becuase the linear distance that the rack moves is a constant.

710, the problem with making the arm shorter is that you will run into rubbing problems because the you will be causing the wheel to be at a greater angle when at full lock. From your ealier post I think you said there is not stop adjustment. I hear that those with 235s up front already rub.

T.J.
 
Think of it the opposite... if you extended the arm by one foot. The wheel would barely turn at all becuase the linear distance that the rack moves is a constant.

710, the problem with making the arm shorter is that you will run into rubbing problems because the you will be causing the wheel to be at a greater angle when at full lock. From your ealier post I think you said there is not stop adjustment. I hear that those with 235s up front already rub.

T.J.
-We're currently in the works of a different method to increase the steering response...

But yes the side affect is that the added steering angle may cause rubbing. But its a small price to pay for the benefits. Rubbing the tire on the inner tub of the chassis isn't that harmful for the tire nor wheel (unless the tire is stretched too much and is contacting wheel on chassis) but for all of the extreme setups I have driven on, 235s rubbing up front is not that bad...
 
710, the problem with making the arm shorter is that you will run into rubbing problems because the you will be causing the wheel to be at a greater angle when at full lock. From your ealier post I think you said there is not stop adjustment. I hear that those with 235s up front already rub.

T.J.

Yes I thought of that too, they would rub. I put the NSX on the lift last night and measured things again. Thicker end stops in the rack could be made and installed.
And I agree, looking around at all the NSXes with wider wheels out there, I assume most rub already.

I am designing a way to install the steering brackets and short arms without removing the upright from the car. (and, no it’s not using those existing two spare holes in the upright).
I’ll keep you posted.
Peter
 
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Peter, I like your arm idea (addresses both manual & power steering, seems easily reversible, produces the necessary result). Just being impatient I guess, but as soon as you put your "package" together, start a signup thread...I'm betting you'll get a very positive response. Good luck! (starting to save - now!:tongue:).

Mike
 
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thanks everybody for the feedback.

I have a design now and I have asked a machine shop with CNC tools to make me a prototype, pending some measurements.
anyway the machine shop has xmas and new years now, they are a little bit closed for a couple of weeks. :-)

My design is made to mount on the car without removing the upright. This is important because, from what I have heard, it is difficult to remove the ball joints on our NSXes. So removing the upright is not necessary.

There is 1 bracket and 1 arm (per side).

the Bracket:
The bracket is mounted on the car in a garage, mounting of a few bolts, drilling of 2 holes (per side). No thread tapping anywhere is required, the 2 holes to be drilled do not have to be precise, anybody can do it. And these holes are not in a strength sensitive area so there will be no loss of strength to the upright.
The mounting of the bracket is in a clean and professional way. It looks like Honda made the kit. Dare I say …um …..a Type R steering kit?
After the bracket is mounted to the car upright, the steering arm bolts to the bracket with 2 bolts then the steering tie rod end cone bolt is mounted into the steering arm just like the original. Would probably take 30 minutes per side.

the Arm:
The arms can be removed / changed at the track or anywhere, no need to have a garage. Changed easily, while the bracket stays on the car permanently.


If the bracket can be aluminium (I think so) and passes the testing for strength, then it will be anodised in blue or red or whatever.

The steering arm bolts to that, I will start with a steel one, so black.
Then an aluminium one. If the aluminium one is strong enough, then that will be anodised too so it will look nice. But the design allows for a thick steering arm, I am leaving room for that, so probably it can be aluminium too.
The aluminium arm would have to have an insert in it, like the NSX has, that will cost more.


The shorter arm idea solves all the problems for all people:
-Different steering ratios from easier to park longer arm to original length to sporty to drift. Can be easily changed on site, back an forth, depending on what you like.
-Fits Left Hand Drive and RHD cars.
-Fits power steering and manual steering cars.
-Allows different heights of the arm/tie rod end (for playing around with the bump steer and for lowered cars- this is for the circuit racers).
-It is all the same product, just slightly different length arms need to be mounted. Easy to change for quicker or slower steering depending on what venue you happen to be at. Can be changed on site. If you accidentally ordered arms that you don’t like the feel of, then I can send you different length ones. The actual arms are the lesser cost items in the kit so it will be easy and cheap to play around and find a nice steering feel for what you want.
-It will be manufactured and shipped in the States to keep the price down.
-Maybe your choice of colors (anodising).
-Some of the strengthening ribs will be machined with diminishing sizes of holes, so it looks like it was lightened. This is for looks mostly. The design allows this according to the FEA tests I made.
-Will cost much less than the original estimates of the steering rack. Maybe around $500-$800 per car (but give me time to cost this thing properly, I’m not there yet. I am still in the prototype phase).
-Will be strong enough for me, I tend to beat the hell out of cars.
-Will be tested on the circuit.
-Will be tested to destruction in various ways (hydraulic press, really big hammers, and fatigue and vibration tests – we have the tools here for that because of the engineering business)


I have also looked into the new end stops (as you may have figured, these may be needed), so far I think they will be easy too.

I will post an image of the kit when I have made some final measurements and spoken again with the machine shop.
merry xmas and happy new year!
peter
 
:biggrin::biggrin::biggrin::tongue: :cool: :smile::wink:
You, sir, are a man of action!
 
My design is made to mount on the car without removing the upright. This is important because, from what I have heard, it is difficult to remove the ball joints on our NSXes. So removing the upright is not necessary.


710, I am very impressed with your openness and the amount of information you are giving us. I was initally disappointed in this arm but I am coming around.

I would like a couple more peices of information. I have a feeling that this is already in your plan but I just want to be sure.

-I think you need to measure the current bump steer, and what the new kit will change it to
-I think you need to measure the current % ackermen and what % the new kit will change it to
-This may be asking too much but for those of us with lowered cars you might consider doing this in .5" or 1" increments.

Thanks,
T.J.
 
710, I am very impressed with your openness and the amount of information you are giving us. I was initally disappointed in this arm but I am coming around.

I would like a couple more peices of information. I have a feeling that this is already in your plan but I just want to be sure.

-I think you need to measure the current bump steer, and what the new kit will change it to
-I think you need to measure the current % ackermen and what % the new kit will change it to
-This may be asking too much but for those of us with lowered cars you might consider doing this in .5" or 1" increments.

Thanks,
T.J.

Hi TJ,
The bump steer will be exactly the same as the original car if I make a steering arm so the ball of the tie rod end is in the same place.
If I make an arm slightly higher, then the bump steer will be altered. That is the nice thing, we can make the arms anything we want without changing the bracket.
Including for lowered cars.
Actually, I could ask how many inches the car is lowered and then provide an arm exactly that much lower. In increments also would be possible.
My design of the arms is not what people first think. With mine, they are stubby things, really strong and they will be machined out of a lump of aluminium.

Ackermann is the same thing. If the steering arms are shorter, then I will machine the arms to be slightly leaning in to compensate. This will have to be calculated, when I have all the info in my computer, I can do it.
Another thing nobody mentioned is the position of the steering housing. It doesn’t have to be moved, but if one is a perfectionist, then it would be good to move it forward slightly to match the sorter arms. But a cross member of the car is in the way so we can only move it forward about half an inch max (if that). This will be for later because it won’t improve things so much. Leaning the arms slightly for the Ackermann will be enough.
The next biggest problem I have is to find someone to machine the conic holes in steel inserts for the tie rods. They will be pressed into the alu arm, like the original. That’s the next problem and this is something that people should be afraid to do themselves, it is critical.

Peter
 
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What ever happened with this project? I am still interested if anyone has a solution to quickening the steering. Lots of good ideas appear to have been tossed around and it appeared close to becomming a reality!:biggrin:

Up date??

Thanks,

Tytus
 
yea I'm interested too. Taking delivery of my nsx end of this month and it'd be nice to have the quicker steering ratio mod done.
 
Working on it. I bought some uprights and measured them up.
Now I‘m changing the first arm prototype, to make a better fit.
 
Alright! Glad to hear work is in progress, keep up the good work 710 and looking forward to hear good news from you.
 
710

"The next biggest problem I have is to find someone to machine the conic holes in steel inserts for the tie rods. They will be pressed into the alu arm, like the original. That’s the next problem and this is something that people should be afraid to do themselves, it is critical. "


the way to do it is to measure the cone angle and have a toolmaker modify an endmill tool to have the sides of it matching the cone angle. perfect fit guaranteed.
i could do it but you are in europe.:rolleyes:
 
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