Interesting note on the KWv3. What could over setup or spring rate would recommend then? Sorry, I know this is kind of a thread hijack. Feel free to PM me if you don't want to muddy up this thread.
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- Thread starter liftnot
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Interesting note on the KWv3. What could over setup or spring rate would recommend then? Sorry, I know this is kind of a thread hijack. Feel free to PM me if you don't want to muddy up this thread.
We will create a new thread on the dampers when we are ready.
BWR at Lotustalk has the right approach for your Exige damper set up. see their threads and feedback.
The process of selecting the right springs consist of a few calculations and many other factors. There are over 10 different valves avail. to generate different curves for the Penskes. Therefore, what is good for Billy J. may not be right for you. This is a good source to learn about shocks. Dyson racing knows their stuff. Notice the shock dyno behind:wink: that would be the 1st indication if the shop you visit knows anything about shock set up. If not, they are just selling parts then.
https://www.youtube.com/watch?v=NAlqiLNMhLA
EMI is always in high demand, even Penske told us to wait for his shocks IF ALL possible:biggrin:. Your Exige, like the NSX has a great chassis so its worth the money to extract the most out of it instead of more HP. Ryan Rush here has EMI Penske triple and his time of 1:39
with the crush box at Laguna is 3 sec. slower than the new NSX driven by the Pro - Randy Pobst. Ryan is NA with easy bolt-ons. That car is balanced!!
Entry level dampers by definition are very crude devices and from the video above, you can easily see the Penskes are of instrument quality for good reasons. Detail matters especially on a great chassis.
BWR at Lotustalk has the right approach for your Exige damper set up. see their threads and feedback.
The process of selecting the right springs consist of a few calculations and many other factors. There are over 10 different valves avail. to generate different curves for the Penskes. Therefore, what is good for Billy J. may not be right for you. This is a good source to learn about shocks. Dyson racing knows their stuff. Notice the shock dyno behind:wink: that would be the 1st indication if the shop you visit knows anything about shock set up. If not, they are just selling parts then.
https://www.youtube.com/watch?v=NAlqiLNMhLA
EMI is always in high demand, even Penske told us to wait for his shocks IF ALL possible:biggrin:. Your Exige, like the NSX has a great chassis so its worth the money to extract the most out of it instead of more HP. Ryan Rush here has EMI Penske triple and his time of 1:39
with the crush box at Laguna is 3 sec. slower than the new NSX driven by the Pro - Randy Pobst. Ryan is NA with easy bolt-ons. That car is balanced!!Entry level dampers by definition are very crude devices and from the video above, you can easily see the Penskes are of instrument quality for good reasons. Detail matters especially on a great chassis.
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Like any manufacturer, Honda designed into the NSX various compromises that bridge sporting intent and everyday functionality. Having MVO design an improved replacement that more reflects sporting intent is not a unique concept. Parts manufacturers that promise improved engine, suspension, braking, or reliability over stock exist for every platform. I think it should be noted that no one, not even a racing driver, wants a "trigger happy" steering rack that promotes instability. In addition, it's not like some drivers haven't experienced snap oversteer in the stock NSX - though that may not have steering rack attribution at all. From the posts by liftnot, MVO will be designing a part that considers suspension geometry, weight, etc, as well as the intended application...provided we (stakeholders) are all comfortable with the assessment of what MVO can deliver.
Even so, the design parameters of the Bishop style is that it has low gain in the straight position and varies to higher gain as more steering angle is applied. Sounds good to me.
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Roman,
have you driven an Elise/Exige? what do you think of the steering at speed? most say its telepathic and thumbs up as a proper sports car should be. We have given this a lot of thought since Bishop came to light way back in 2008 and our NSX is the perfect car to try. Anything less than a NSX is not worth the trouble IMO. Bishop won the award is saying a lot since "seemingly", any machine shop with the proper CNC can turn out a faster rack is not what this is about. As much as we love you to sign up and we understand your concerns are valid, we don't want you to be disappointed after spending big money follow by negative reviews so perhaps this should not be in your plan even we provide all the data to prove on paper. There is certainly nothing wrong with the oem rack so why spend $$$$ for a different rack? that is the question you have to answer yourself. Many people spend big money on bling and make the car bigger and heavier to the point that 17/18 is no longer enough and the car can no longer dance.
Only 60 gets this out of the total 10k+NSX population. its not a money maker and that is not what we are doing this for. We rather take more driving lessons to improve our skills to deal with the twitchy-ness IF comes to that than having a slow rack. We have long WB and lower PMI than oem. This is the same reason we have Ti-Dave's bushings and clamp as many say you can't feel any difference on the street, waste of $$. We think ALL NSX should have Dave's bushings and clamp.
Now we are going to pray for a new email from MVO coming soon.
have you driven an Elise/Exige? what do you think of the steering at speed? most say its telepathic and thumbs up as a proper sports car should be. We have given this a lot of thought since Bishop came to light way back in 2008 and our NSX is the perfect car to try. Anything less than a NSX is not worth the trouble IMO. Bishop won the award is saying a lot since "seemingly", any machine shop with the proper CNC can turn out a faster rack is not what this is about. As much as we love you to sign up and we understand your concerns are valid, we don't want you to be disappointed after spending big money follow by negative reviews so perhaps this should not be in your plan even we provide all the data to prove on paper. There is certainly nothing wrong with the oem rack so why spend $$$$ for a different rack? that is the question you have to answer yourself. Many people spend big money on bling and make the car bigger and heavier to the point that 17/18 is no longer enough and the car can no longer dance.
Only 60 gets this out of the total 10k+NSX population. its not a money maker and that is not what we are doing this for. We rather take more driving lessons to improve our skills to deal with the twitchy-ness IF comes to that than having a slow rack. We have long WB and lower PMI than oem. This is the same reason we have Ti-Dave's bushings and clamp as many say you can't feel any difference on the street, waste of $$. We think ALL NSX should have Dave's bushings and clamp.
Now we are going to pray for a new email from MVO coming soon.
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Tim, yes I've driven Elise couple of times. First time few years back in Chicago and about 3 years ago when I lived in SoCal. Yes the best way to describe the feel is - it's like a big go kart. But it's not the car in oem (no extra aero) that feels as happy as nsx at high speed. I'm talking 100+ mph. It's short wheel base, much lighter vehicle. While it's great I don't think it should be a target for how nsx steering should feel. Sure that's my subjective opinion. It's similar thing when I'm saying that s2000 has numb steering feel. Some argue otherwise. Everything is relative.
Please don't get me wrong. I do understand what's being done here. The only reason I posted above is to disagree with your statement about tech limitations Honda had in 80s.
I happen to have most of Dave's bits as well and I think they are fantastic. But to your point that some don't feel the difference - well same story many run shitty 300+ UTQG rubber and complain about lack of steering feel etc. Everything is subjective until you drop some numbers and measurements into the conversation.
Will keep watching this space. Good luck.
Perhaps Honda didn't install a variable ratio steering rack in the original NSX because they practically couldn't. The magazine Racecar Engineering ran an article about variable ratio steering racks in September 2008, two decades after the NSX was designed. To quote:
Regarding the car becoming twitchy at high speeds: variable ratio steering racks were developed specifically so that the steering would require few turns from lock to lock yet not become twitchy at high speeds. There are a few further quotes from the article in Racecar Engineering discussing that in post #13 of this thread.
So I don't expect the car would become twitchier at high speeds and it would be nice if it required fewer turns from lock to lock. The potential downside I see in a variable ratio rack is that it may make the steering heavier through turns due to the faster ratio off center.
The other factor holding back its adoption is the complexity of designing and manufacturing such a system. Before Nevo Developments could enter the market it had to invest in bespoke software that could cope with the numerous variables and the difficulty of manufacture. A VR rack for F1 needs to be machined to within five microns yet, because of its design, normal grinding and hobbing techniques cannot be used. Nevo is understandably tight lipped about how it achieves these objectives, only revealing that it requires some exceptionally high-end machinery.
For now, VR steering racks are a relatively new, if rather late, arrival in motorsport but, as with all technology, expect to see it trickle down now its benefits have been demonstrated.
For now, VR steering racks are a relatively new, if rather late, arrival in motorsport but, as with all technology, expect to see it trickle down now its benefits have been demonstrated.
Regarding the car becoming twitchy at high speeds: variable ratio steering racks were developed specifically so that the steering would require few turns from lock to lock yet not become twitchy at high speeds. There are a few further quotes from the article in Racecar Engineering discussing that in post #13 of this thread.
So I don't expect the car would become twitchier at high speeds and it would be nice if it required fewer turns from lock to lock. The potential downside I see in a variable ratio rack is that it may make the steering heavier through turns due to the faster ratio off center.
I actually have my eye set on their Penske doubles. I've purchased from Blackwatch and they are well known in the Lotus world. Thanks for your feedback.
I will go ahead and echo the sentiment that the Elige (Elise + Exige) platform provides near telepathic steering and feel. That said, it IS a completely different car than the NSX. Doesn't mean that there isn't something in the character of the Elige that can't be mimicked on the NSX. As well, while the Elige has amazing steering and feel from factory, it actually can be improved a lot with the Penske's and a beefier sway bar up front. I've personally ridden in an Elise that was setup for autocross with the BWR Penske doubles and their track sway bar --- I didn't think it was possible but it made the car EVEN better. Turn in was even more direct and immediate, ride was more comfortable but even more stable and solid. Hard to describe without being a VERY experienced driver, I guess.
Do things right the 1st time is much cheaper! Way to go Butters:wink: Fred was not able/willing to produce a set for the NSX due to lack of data. He is right. Wrong data = wrong set up.
Chris let me drive a 400hp SC Elise while it was at DRS cuz it had carbon brakes......no noise, stops at cold...hmmm
This is fresh off the oven. Along with the Cubs won the World Series, it makes two best news in a long time.
As promised by MVO for an update this week. See attached pdf for more detail. All the pictures made us miss working at Nissan as we had a CMM at QC and we can just walk in and ask Fred to "check it out". Read the pdf report on the bottom of the page here. http://pole2flagracing.com/variable-ratio-steering-rack.html
Thank you again for your patience. We have had the opportunity to acquire all of the geometry from the OEM steering gear to perform our calculations.
I have included a PDF document with photos of the process to date and a specifications table of the information acquired. Next we will be analyzing the data to determine the possible gear teeth geometry options going forward. This document is not complete, but I wanted to keep you in the loop with our progress to date. We will be performing the gear calculations next week and will have more for you then.
Chris let me drive a 400hp SC Elise while it was at DRS cuz it had carbon brakes......no noise, stops at cold...hmmm
This is fresh off the oven. Along with the Cubs won the World Series, it makes two best news in a long time.
As promised by MVO for an update this week. See attached pdf for more detail. All the pictures made us miss working at Nissan as we had a CMM at QC and we can just walk in and ask Fred to "check it out". Read the pdf report on the bottom of the page here. http://pole2flagracing.com/variable-ratio-steering-rack.html
Thank you again for your patience. We have had the opportunity to acquire all of the geometry from the OEM steering gear to perform our calculations.
I have included a PDF document with photos of the process to date and a specifications table of the information acquired. Next we will be analyzing the data to determine the possible gear teeth geometry options going forward. This document is not complete, but I wanted to keep you in the loop with our progress to date. We will be performing the gear calculations next week and will have more for you then.
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- 27
I am squirming in my seat at work I am so excited about this. I remember the change in driving feel I had when I converted my e30 track rat to the Z3 steering rack, what a DIFFERENCE! The idea of upgrading the NSX in the same way has me all kinds of giddy. Thank you for putting forth the effort to accomplish this!
We are in good hands....with MVO:smile:
It's not apples:apples to just look at the steering ratio without also considering the geometry of the knuckle. A lot of modern cars have really slow steering rack ratios but VERY short steering arms on the knuckle. On paper, one would draw erroneous assumptions of a car's steering purely by looking at the steering ratio.
I sure hope this new setup isn't as twitchy as the Elise/Exige, which weighs ~1,000lbs less than the NSX and therefore does not need as slow of a steering ratio or as big of a steering wheel to turn the car at low speeds. If you dropped an Elise/Exige rack and steering wheel into the NSX, it would be extremely difficult to turn in parking lots.
During development, all of KW's setups go on their 4-post shaker rig. Are you implying that KWs don't improve the car? What makes the 343/343lb spring rates (457/457lb for clubsport) "odd"? The OEM NSX has stiffer rear spring rates than front, the majority of Japanese tuners have historically gone with stiffer rear spring rates than front, and the OEM Type-S, Zanardi, & Type R run stiffer front springs than rear. A lot of American tuners and racers run stiffer front springs than rear, and it seems like the Japanese are following suit and starting to run stiffer front springs than rear.
KW found the 343/343lb spring rate to achieve the streetable balance and trackable performance targets they were looking for while taking into consideration the natural frequency of the car.
Also keep in mind that only half the weight of a coilover is unsprung.
Thats why we are using MVO for their expertise. We have been waiting for our turn since May and we just barely got started. We only know this kinda stuff on paper and yes, its not just about a quicker ratio. We need to consider the ramifications of that. Who knows, maybe MVO would not recommend a faster ratio after their assessment and our R&D money is down the drain but at least we will learn something about steering.
Elise WB is much shorter than the NSX. Our car is mid-2500 and losing so for cars approaching 3500lbs, you might curse us in the parking lot. Not saying you don't know your stuff.
Of course KW works well. compare to most existing AM shocks. For starter, the motion ratio F/R is quite a bit different so requires a different rate. Haven't seen this can be achieved thru "custom" valving. We will soon post a new thread on Penske shocks working with Eric at EMI racing. Although we don't have the skills to clock 1:39 @3000 lbs. w/ 300 BHP like Ryan Rush but we sure like to set up a car that IS capable of 1:39.....and lighter weight. What can you remember from driving Ryan's car?
Basically, they don't/can't make cars like the old NSX anymore and we want to have the best parts and the best set up to have the best analog experience b 4 we kick the bucket. You may know this but others may not, there is no such a thing as off-the-shelf Penske. ALL Penske shocks are custom valved for good reasons. And Penske doesn't sponsor anybody. Everybody pays for their Penske shocks even their own teams. When we call Penske cuz EMI is too busy, even they told us to wait for EMI's shocks if all possible. Erik is that good. We have been waiting close to two years now but we are not racing. Get back to the topic.
>Also keep in mind that only half the weight of a coilover is unsprung.
exactly, from a design pov, we think replacing steel with steel = mod. (its fine for other sports cars) replacing steel with lighter parts if possible to take advantage of the rest of the suspension is an upgrade. why increase the unsprung wt. if you can help it. Its much sexy buying things in ounces than paying things by the pound.
Stiffer front and softer rear is what we prefer. Never understood the other way around.
Elise WB is much shorter than the NSX. Our car is mid-2500 and losing so for cars approaching 3500lbs, you might curse us in the parking lot. Not saying you don't know your stuff.
Of course KW works well. compare to most existing AM shocks. For starter, the motion ratio F/R is quite a bit different so requires a different rate. Haven't seen this can be achieved thru "custom" valving. We will soon post a new thread on Penske shocks working with Eric at EMI racing. Although we don't have the skills to clock 1:39 @3000 lbs. w/ 300 BHP like Ryan Rush but we sure like to set up a car that IS capable of 1:39.....and lighter weight. What can you remember from driving Ryan's car?
Basically, they don't/can't make cars like the old NSX anymore and we want to have the best parts and the best set up to have the best analog experience b 4 we kick the bucket. You may know this but others may not, there is no such a thing as off-the-shelf Penske. ALL Penske shocks are custom valved for good reasons. And Penske doesn't sponsor anybody. Everybody pays for their Penske shocks even their own teams. When we call Penske cuz EMI is too busy, even they told us to wait for EMI's shocks if all possible. Erik is that good. We have been waiting close to two years now but we are not racing. Get back to the topic.
>Also keep in mind that only half the weight of a coilover is unsprung.
exactly, from a design pov, we think replacing steel with steel = mod. (its fine for other sports cars) replacing steel with lighter parts if possible to take advantage of the rest of the suspension is an upgrade. why increase the unsprung wt. if you can help it. Its much sexy buying things in ounces than paying things by the pound.
Stiffer front and softer rear is what we prefer. Never understood the other way around.
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I probably won't be interested if the new rack is significantly more difficult to turn at low speeds. Yes the Elise's short wheelbase and 2,000lvs makes it easier to get away with a quick ratio and small steering wheel, which may or may not work as well on a 3,000lb nsx.
Just because the NSX has different F-R motion ratios, does not mean it NEEDs different spring rates. Ideal spring rates depend on a ton of factors and even so, you can turn the same lap times with vastly different spring rates, but the car will handle and feel very different.
Any manufacturer who engineers a product for a given car has overhead in that design and sells kits to offset that development and to make a profit. KW has tested the NSX platform and developed a product for street/track use. That is not Penskes business model, nor many other damper companies, so they will either require you to do the measurmemts and testing, or will defer to someone who already has for that platform (like Erik for Penskes on the NSX).
Some tuners go with stiffer rear rates than front, others go with stiffer front than rear. It all depends on what you're looking for and your personal tastes of how the car feels and handles. This has been discussed a lot on various threads over the years.
Everyone has different budgets, goals, objectives, etc... For most people who want an extremely competent track setup that gives a great ride quality (some say better than stock) without breaking the bank, the KW V3 has been a popular option that fits the bill. If your budget is greater and the need for reducing weight everywhere possible and you like to use high end stuff, go with a custom Penske setup. If I had an unlimited budget and wanted F1 technology and the best of the best, I would go with something different. Choose what fits your budget, needs, and goals.
Ryan's car could probably break into the 1:37s, especially when using the cool, amazing rear spoiler that he runs, which gives his car much needed rear downforce. His setup was a bit too loose with the stock rear wing.
Just because the NSX has different F-R motion ratios, does not mean it NEEDs different spring rates. Ideal spring rates depend on a ton of factors and even so, you can turn the same lap times with vastly different spring rates, but the car will handle and feel very different.
Any manufacturer who engineers a product for a given car has overhead in that design and sells kits to offset that development and to make a profit. KW has tested the NSX platform and developed a product for street/track use. That is not Penskes business model, nor many other damper companies, so they will either require you to do the measurmemts and testing, or will defer to someone who already has for that platform (like Erik for Penskes on the NSX).
Some tuners go with stiffer rear rates than front, others go with stiffer front than rear. It all depends on what you're looking for and your personal tastes of how the car feels and handles. This has been discussed a lot on various threads over the years.
Everyone has different budgets, goals, objectives, etc... For most people who want an extremely competent track setup that gives a great ride quality (some say better than stock) without breaking the bank, the KW V3 has been a popular option that fits the bill. If your budget is greater and the need for reducing weight everywhere possible and you like to use high end stuff, go with a custom Penske setup. If I had an unlimited budget and wanted F1 technology and the best of the best, I would go with something different. Choose what fits your budget, needs, and goals.
Ryan's car could probably break into the 1:37s, especially when using the cool, amazing rear spoiler that he runs, which gives his car much needed rear downforce. His setup was a bit too loose with the stock rear wing.
Ryan made a smart move to visit Erik and spent his money the right way. Several people have done so in the past. Heck, if you have the skills, you can squeeze more time out of the yellow Bilstein but we don't. Many people spend money on parts that yield little or no improvement on the car or even make the car worse but its the perception of speed that sells. As long as "you" think its making a difference, that is all that matters. Its always a positive move to improve the car's cg, pmi, weight, moi, rc, rotational inertia, unsprung, tires, aero, etc. These are fundamentals and we have little budget to make it happen.
MVO proposed to build 3 different racks with 3 different ratios. Most aggressive, modest aggressive, aggressive and test them on a car. That is what a top team will do to suit different tracks but we don't have that kinda of budget. Say at $2500 ea. x 3 = a small price to pay to make the whole package just a bit better to win. We can't go that route so we are working with them to come up with an alternate plan. We are basically asking them to hit a home-run but will settle for a triple. We trust they have all kinds of data on all kinds of cars....from light weight open wheel to regular rally/DTM/JGTC cars or sports cars. Its still too early to draw a conclusion and its not for everybody.
MVO proposed to build 3 different racks with 3 different ratios. Most aggressive, modest aggressive, aggressive and test them on a car. That is what a top team will do to suit different tracks but we don't have that kinda of budget. Say at $2500 ea. x 3 = a small price to pay to make the whole package just a bit better to win. We can't go that route so we are working with them to come up with an alternate plan. We are basically asking them to hit a home-run but will settle for a triple. We trust they have all kinds of data on all kinds of cars....from light weight open wheel to regular rally/DTM/JGTC cars or sports cars. Its still too early to draw a conclusion and its not for everybody.
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mark me down as interested pending initial reviews of steering effort vs. quickening of rack.
While I do have some of Stuntman's concerns about the increased effort in parking lot situations, I would trade a little time in the weight room for the steering being a little less vague on center and not having to shuffle/cross as much autocrossing.
While I do have some of Stuntman's concerns about the increased effort in parking lot situations, I would trade a little time in the weight room for the steering being a little less vague on center and not having to shuffle/cross as much autocrossing.
Thanks! Sent :biggrin:
New proposed VR Curve
We spoke with THE steering guru at MVO at length. We have a meeting to go now but this getting exciting so will type more later. we did discussed all the concerns of yours posts above. Here is the new curve but there is still more discussion going on before the final ratio so don't throw any darts yet. One comment he did make was 20:1 is for the ladies.:biggrin: not for better handling and performance.
We spoke with THE steering guru at MVO at length. We have a meeting to go now but this getting exciting so will type more later. we did discussed all the concerns of yours posts above. Here is the new curve but there is still more discussion going on before the final ratio so don't throw any darts yet. One comment he did make was 20:1 is for the ladies.:biggrin: not for better handling and performance.
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- Joined
- 9 October 2012
- Messages
- 1,953
This is getting more interesting.
Quick Q: How come I don't see vehicle speed on this chart. Or any other external factors this rack will use to alter the gain?
//quite a sexist comment by that guy. Funny timing also: http://jalopnik.com/meet-the-woman-who-wont-let-a-spinal-cord-injury-stop-h-1788856797
They all went home before we could ask more questions:frown:. Have to wait until next week. They did make a comment that weight and the WB don't have as much effect as you would think and many VR racks on the market are either electronically controlled thru s/w or thru P/S. Bishop designed the patented profile unto the rack and pinion with high precision machining.
calculated OEM is ~2.4 turn to turn and the new rack is ~2.1. Visually they couldn't tell the variable section of the oem rack, so if it is indeed a 18.2-20.8 rack, its rather minute.
The most accurate way to overlay the vehicle speed is to instrument the car w/ the new rack like the MVO flyer of the MBenz rack showing the yaw gain comparison. You should care more about the steepness of the curve more than the vehicle speed cuz on-center to lock is shown. We are not doing mass production. We've got a small budget and all your questions may or may not be answered to your liking. Accurate data cost a lot. Even if we have that data, we are sure there will be more on going questions ie, how would it feel on my car? and this project will cost even more and will never end. This is their 1st initial proposal and we'll have more discussions soon. This is for folks who trust us, and MVO to produce a higher performance VR rack because at the end of the day, no body can tell you how it feels on your car and that can not be quantified. Yes it will be harder to turn at zero speed and quicker at higher speeds so your turn-in or accident-avoidance can be quicker than the oem rack. you must be willing to adjust to that. This rack will be made for quicker response and performance so if your car is heavy, it may not be for you as our car is at no-worry 2500lb. We trust MVO knows what they are doing and steering is all they do. We think its better to wait until our discussion with MVO is finished, then see if you have gain a piece of mind. If not, we are sorry.
Those of you who are seriously thinking about this, you should/already have tighten up your chassis and use good tires and good shocks to take advantage of this upgrade.
EOT = end of travel.
Nathalie's radial control is uber cool. We don't mind a control like that!
calculated OEM is ~2.4 turn to turn and the new rack is ~2.1. Visually they couldn't tell the variable section of the oem rack, so if it is indeed a 18.2-20.8 rack, its rather minute.
The most accurate way to overlay the vehicle speed is to instrument the car w/ the new rack like the MVO flyer of the MBenz rack showing the yaw gain comparison. You should care more about the steepness of the curve more than the vehicle speed cuz on-center to lock is shown. We are not doing mass production. We've got a small budget and all your questions may or may not be answered to your liking. Accurate data cost a lot. Even if we have that data, we are sure there will be more on going questions ie, how would it feel on my car? and this project will cost even more and will never end. This is their 1st initial proposal and we'll have more discussions soon. This is for folks who trust us, and MVO to produce a higher performance VR rack because at the end of the day, no body can tell you how it feels on your car and that can not be quantified. Yes it will be harder to turn at zero speed and quicker at higher speeds so your turn-in or accident-avoidance can be quicker than the oem rack. you must be willing to adjust to that. This rack will be made for quicker response and performance so if your car is heavy, it may not be for you as our car is at no-worry 2500lb. We trust MVO knows what they are doing and steering is all they do. We think its better to wait until our discussion with MVO is finished, then see if you have gain a piece of mind. If not, we are sorry.
Those of you who are seriously thinking about this, you should/already have tighten up your chassis and use good tires and good shocks to take advantage of this upgrade.
EOT = end of travel.
Nathalie's radial control is uber cool. We don't mind a control like that!
i have a 91. the turn-in is very SLOW compared to my s2000 AP1. so will this rack this problem? I don't mind if steering feels heavy or heavier.
Yes a quicker ratio definitely makes the turn in quicker....(how much quicker?) we have no way to quantify that except looking at the graph they provide. Its not the final graph and we are discussing more in depth with MVO next week.
On a side note, If we ask for more hard data, the more money and time it will take and it will drive the cost out of the park. Often times, even if we have all the data, some people still won't buy and that is not our focus here. We think it will be harder to turn at rest so you must be willing to adapt. Sounds like you are
On a side note, If we ask for more hard data, the more money and time it will take and it will drive the cost out of the park. Often times, even if we have all the data, some people still won't buy and that is not our focus here. We think it will be harder to turn at rest so you must be willing to adapt. Sounds like you are
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When my brother drove my NSX a few months back, he was surprised how heavy the steering became in fast turns compared to his Porsche 991.
My neighbor just had an electrically-assisted steering column made for his old Healey by these guys and is really happy with that. He says the steering feel hasn't changed, it's just not as heavy anymore.
A variable ratio rack combined with an electrically-assisted steering column could make both the men and the ladies happy! The electric steering column would add extra weight to the car, though.
My neighbor just had an electrically-assisted steering column made for his old Healey by these guys and is really happy with that. He says the steering feel hasn't changed, it's just not as heavy anymore.
A variable ratio rack combined with an electrically-assisted steering column could make both the men and the ladies happy! The electric steering column would add extra weight to the car, though.
Well this electrically-assisted steering column coupled with the VR Rack could offer the best of both worlds...
Primers, we need your Vote!
WHAT? again? Two votes in a week?
The discussion we had with MVO, had yielded the following:
1)The proposed 14.46:1 on center to 20:1 at lock is the most aggressive VR ratio based on our criteria of improving handling and performance specifically for our NSX.
the 18.2-20.8 oem ratio was barely noticeable of the donated unit which does not seem worn. We vote for this ratio based on their recommendation. The person we spoke to has been with Bishop( in Australia) and now MVO USA for 25+ years and all the teams from F1 down, he is responsible for the design. Thus, its hard to learn everything in one phone conversation. However, they invited us to visit their shop and we just might take up on it after our Exedy carbon clutch install and gearbox refresh with REM treatment so realistically, the visit will be early next year.
2)The twitchy-ness(if any) of the car is more or less the driver's behavior not due to the VR so a learning curve of the new rack is a must and suspension change(ie, roll stiffness, springs) may be also.
3)Its impossible to quantify the "steering feel". its very subjective to each person. For the same weight/driving condition, the lower steering ratio mean higher rack gain of mm/rev., the higher the steering wheel torque. You will need to work harder when you turn the steering at zero mph but how much harder is unknown without making multiple prototype of different ratios and install them in different cars for comparison. That is the logical approach but that does not seem practical for us as the project will never end.
4) The s/w to produce the a VR ratio is proprietary. Any company (Quaife, Woodward, Titan, etc.) want to produce a VR rack typically go thru MVO because the tooling alone is a huge investment.
5) In terms of engineering, the RHD would require the same amount of work as the LHD(assuming they are not 100% identical) because they have seen this in other vehicles but if the NSX is a mirror image, the amount of the work is much less. We just don't know at this point.
6) We are merely reverse engineer this part to yield a quicker VR ratio as the oem is practically fixed @ 20:1. The donated oem rack does not look worn but we are not starting from a new rack and we don't have any design drawings to tell us the stack up and the tolerances.
7)A new housing will put us way north of $5000+ maybe even $7K+ as more engineering time is needed. This is not an option for us. So in order to stay within the original quote, MVO will provide just the pinion and the rack. P2F/Applied will rebuild your existing unit to keep the cost in control. We still need to check the dealer for parts availability and we won't know 100% if your rack is rebuildable until we disassembly it.
8)Questions are welcome but we want to stay away from continuous, never ending what-ifs, subjective questions that we can't answer. Remember, some like rice, some like beef, you have a choice. Our guess is some will love this new ratio and some will hate it. You should go in with an open mind. You can always go back to the oem ratio but there is no refund on custom made parts. Think carefully.
The bottom line is: do you want a quicker rack made by the world's best and are you willing to adjust to its new behavior?
Tell us what you think about the new ratio before we take the next step.
WHAT? again? Two votes in a week?
The discussion we had with MVO, had yielded the following:
1)The proposed 14.46:1 on center to 20:1 at lock is the most aggressive VR ratio based on our criteria of improving handling and performance specifically for our NSX.
the 18.2-20.8 oem ratio was barely noticeable of the donated unit which does not seem worn. We vote for this ratio based on their recommendation. The person we spoke to has been with Bishop( in Australia) and now MVO USA for 25+ years and all the teams from F1 down, he is responsible for the design. Thus, its hard to learn everything in one phone conversation. However, they invited us to visit their shop and we just might take up on it after our Exedy carbon clutch install and gearbox refresh with REM treatment so realistically, the visit will be early next year.
2)The twitchy-ness(if any) of the car is more or less the driver's behavior not due to the VR so a learning curve of the new rack is a must and suspension change(ie, roll stiffness, springs) may be also.
3)Its impossible to quantify the "steering feel". its very subjective to each person. For the same weight/driving condition, the lower steering ratio mean higher rack gain of mm/rev., the higher the steering wheel torque. You will need to work harder when you turn the steering at zero mph but how much harder is unknown without making multiple prototype of different ratios and install them in different cars for comparison. That is the logical approach but that does not seem practical for us as the project will never end.
4) The s/w to produce the a VR ratio is proprietary. Any company (Quaife, Woodward, Titan, etc.) want to produce a VR rack typically go thru MVO because the tooling alone is a huge investment.
5) In terms of engineering, the RHD would require the same amount of work as the LHD(assuming they are not 100% identical) because they have seen this in other vehicles but if the NSX is a mirror image, the amount of the work is much less. We just don't know at this point.
6) We are merely reverse engineer this part to yield a quicker VR ratio as the oem is practically fixed @ 20:1. The donated oem rack does not look worn but we are not starting from a new rack and we don't have any design drawings to tell us the stack up and the tolerances.
7)A new housing will put us way north of $5000+ maybe even $7K+ as more engineering time is needed. This is not an option for us. So in order to stay within the original quote, MVO will provide just the pinion and the rack. P2F/Applied will rebuild your existing unit to keep the cost in control. We still need to check the dealer for parts availability and we won't know 100% if your rack is rebuildable until we disassembly it.
8)Questions are welcome but we want to stay away from continuous, never ending what-ifs, subjective questions that we can't answer. Remember, some like rice, some like beef, you have a choice. Our guess is some will love this new ratio and some will hate it. You should go in with an open mind. You can always go back to the oem ratio but there is no refund on custom made parts. Think carefully.
The bottom line is: do you want a quicker rack made by the world's best and are you willing to adjust to its new behavior?
Tell us what you think about the new ratio before we take the next step.
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