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EOI Sequential gearset for NSX

Mate i am the same but if you could get a reasonable deal on this and you had the cash and tracked your car why not
 
I don't think that Robfenn's Hewland has a clutch. I could be wrong. Scammy I hear what you are saying but Fraser has a lot more dedicated track car than I do. Perhape the extra 10th's he shaves matter to him.

I don't know much about these things. I'm going to sit back and read and learn.
Hewland, X-trac, quaife, jerico, holinger, etc... They all have clutches (very small diameter, multi-plate, hard to modulate) that are used from a start and often on downshifts during endurance races to prolong its life. Scuderia Corsa advised to use the clutch on downshifts during the 24hr of Daytona which was interesting with paddleshifters.
 
Blimey......... got nothing for ages and now lots of replies all in a day !! :)

OK so here's my answers to most questions I think.

Billy is totally right, this sequential gearset doesn't change the need for a clutch. In fact I think having a clutch is great as it offers the chance to pootle around town at whatever speeds you like.......accelerate, clutch in, either push the lever or pull the paddle and then let the clutch back out however fast or slow you like............ so in that mode of driving it really offers you the same driving experience you already get.

Now if you really wanted to drive it flat out, you simply accelerate and then push the lever or pull the paddle with no clutch needed and you will obviously get a way more aggressive up change, but no clutch needed, so it'll offer you the option to drive how you like. The intention will be to have a fairly straight forward way (button on dash or certain process with paddles) to be able to drop from whatever gear you're in back to neutral as the issue a lot of people don't register when they first get a sequential is that theirs no skipping gears so jumping from 2nd to 4th isn't possible, you need to go through each gear on the way up and down. Now to me that's no big deal but to some it seems to be so making sure we can go from say 3rd to neutral when you roll up to a set of lights is a nice feature so it's been factored into thoughts as we see if this whole process is even possible.

And that's the stage we're still at, as I mentioned, we haven't even had chance to look at an OEM casing yet, but we will soon, it's really just an idea for our needs and I wanted to get an expression of interest for the street / track users as well as the dedicated track people out there.

It will be dog engagement........ its the only real way to do it effectively so there is a certain "clunk" when they engage relative to what some would be used to, but I doubt it'll really be an issue for most once you're rolling.........

Time saved on changes........ well this is the real eye opener for some people. We all think we're quite slick on our gearchanges, but at best usually it's a 500ms-600ms exercise to disengage the clutch, pull the gear and then clutch out and apply power again............. now at our local track we have 13 gear changes per lap or 6.5 seconds that the car isn't being pushed forward when it could be since we're changing gears. With a sequential gearset with flat shifting, that 6.5 seconds drops to around 1.5-2 seconds (100-150ms per change) so we gain 4 seconds on laptime with no extra effort !

Now that's a simplistic view of course and there are other factors that my see us not get that gain, but it will still be a massive gain in time....... and for us having a paddle shift means we can keep the hands on the wheel which is always good in a racing scenario...... not only that, the changes are so quick you can change up mid corner if you need to without upsetting the car which just isn't realistic in a manual car so there are other advantages, but the major one is time saved on the changes themselves.

As I said, it may end up being a big wild goose chase if it's not realistic to get a sequential setup into an OEM casing, but fingers crossed it's do able as I'm super excited about getting something cost effective for people to help take the NSX up a level on the track.

I would be almost certain that if it's possible that it would be a 5 speed...... I might be wrong, but as you mention I think strength of gears would be the biggest reason.

The guys making it are making us, well have already made us actually, a gearbox for our FZ12 supercar project and so that's where we've got to talk to them about the NSX options and they have worked with a well known UK company that specialises in sequential shift controls and so they will supply piggyback ECU to control the gearbox and shifts that will be tied into your engine ECU for ignition cuts etc so for the stick version that will be all you need. For the paddle shift version there will be added cost of course since the actuation of the gearbox will be controlled by their own ECU but will need extra parts to actuate the gears themselves and possibly some kind of air pump (but might be electric actuators, not sure yet)

So basic system will see a stick to operate the system with added cost around a paddle shift option. Oh yeah, forgot to add, this will be a closed loop system. For those that don't know what I mean, open loop means that when doing flat upshifts the ECU is programmed to wait for a certain time, lets say 200ms and then reapplies the power back without knowing if the gearchange has been made successfully which isn't ideal on a number of levels. With the help of sensors in the gearbox you can make a closed loop system where the ECU is signalled to cut power for a gearchange, the change happens and then sensors in the gearbox confirm the change has happened and then the ECU is told to reapply power........ if the change never happens then the ECU doesn't reapply the power which is the desired option as reapplying power mid shift can do some serious damage to the dogs and other parts of the box.

Hope that's answered everything !
 
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I'd be surprised if they are able to make it a sequential in the stock casing. The least expensive way to effectively get the same shift speed benefit is to leave the H-pattern and just put dog rings in. You won't have the sequential nature or ability to hook up paddle shifters but it would be the easiest way to get the same performance.

Also please mimic the Japanese gear ratio and not the US and shorten 5th gear.
 
It may well turn out not to be possible as mentioned, but I'm sure it won't take them long to decide once they get the box. It's possible that even if they can't do the OEM casing that we will press ahead with a totally custom made box, but obviously cost becomes an issue at that stage so we'll have to play it by ear.

Gear ratio wise they'll all be custom made to suit so ratio changes won't be an issue....... if we get that far I'll make sure we come back and get an idea of what people would like to see. They make all their own gears so anything is possible.
 
It's funny that this thread doesn't violate any rules, but mine did on gears and lsd. Especially with Doc posting in here too........

I know a company that specializes in making gears that may be of help to you if you need one. Just PM me if are interested. Good luck too!
 
Sorry not really sure what your thread was about, and embarrassed to say that I don't know what the rules are around posting, but I'm not trying to sell anything here. Even if these guys make something for our needs I won't be selling anything it'll be up to the users here to purchase from these guys direct..... apart from that side of things I wouldn't know any reason why this thread would break any rules.

Thanks for the offer, but they won't need any help making gears.
 
No sorry, no news yet. I imagine we won't get any solid info for a while to be honest.......... it's a real side project for these guys which is why I was trying to gauge interest as if there was enough it would possibly meant they would escalate it to a higher priority and we'd all get our gearboxes sooner than expected !! :)

I will post info as soon as I have something......
 
Sorry I haven't posted back any info for a while, but there's none to tell at this point as the OEM gearbox I organised hasn't got to them yet..... (it's a favour from a friend over there in the USA) so it's hard to organise from this side of the world but we will get them the OEM gearbox soon hopefully and once we do then it won't take long to get an idea of what is and isn't possible.
 
Just ran across this thread. Would be interested if the price stays reasonable. Its insane how much time is lost shifting a traditional H-pattern synchro tranny. Sad to say but they are outdated and DCT transmissions will always have a huge advantage. sure hope they can get these made.
 
This isn't going to be a DCT transmission even if it does end up being possible.......... I know you might not have meant that, but just so that's clear for others reading, but from a shift perspective it's close to a DCT's times, just not as smooth.....

The guys still haven't had time to look at the box yet, but as I said originally, it's not a primary project for them, it's a "backburner" project they can fit in when they have time.
 
Unfortunately the guy that was going to help me get a factory gearbox for them to look at has let me down. I've been waiting and waiting as he said he would help but then hasn't so things have stalled a little bit on looking into the possibility of this.

Is there anyone out there around the San Diego area (or I guess anywhere reasonably close) that would be willing to loan us a gearbox to investigate ?? Doesn't have to be going as they're only going to strip it down to see what kind of space there is inside the casing and see what is or isn't realistic.

I'm happy to cover any costs of shipping to and from San Deigo.......... timeframe wise I would imagine they would want a good couple of months with the box if possible as they're having to try and fit it in between their usual production so might not be able to jump straight onto it.......

Anyone out there have something ???
 
Shad might have some lying around
 
That's a bloody good idea........... I knew there was a reason that Prime kept you around !! LOL

Thanks, I'll drop Shad a line and see what he can do for us..... it could be great for both Driving Ambition and the guys making the boxes if it pans out as I'm sure he's got some customers that would be interested.

Thanks again for the great idea !! :)
 
That's a bloody good idea........... I knew there was a reason that Prime kept you around !! LOL

they have tried many times,but I'm too stupid to take the hint
 
I hope this does get off the ground one day, I went for a ride in a NZ Honda Cup car DC5 Integra Type R with a sequential box in it last month and wow I so want one of these now
 
Really interest in sequential gear box.. Either 5,6,or 7 speed..
 
To be honest it may be unrealistic to even make a sequential gearset to fit inside the OEM casing so 6 speed is even less likely and 7 speed is just a pipe dream I would say. If it's even going to work the less gears the better possibly to keep them large enough to take reasonable power, but I guess we wont' know for sure till I can get a box to them which I'm hoping will be very soon now I've sorted out another "loaner" after I was mucked around by my first "loaner" ...........

You can't be too grumpy when you're asking favours !
 
Hi all, just thought I'd drop a quick note to say that there's been no progress made here unfortunately........... I've been let down by the first two people who offered to help and unfortunately I've been unable to get any response at all from Shad at Driving Ambition so if anyone out there knows of someone who has a spare box (doesn't have to be working) that's close to San Diego, or even if you're not, I'd be willing to pay for the freight to get it to San Diego to get inspected so we can see what is possible. I would send my own gearbox, but it's just too expensive to send one from New Zealand !.

Hoping someone can potentially help out so we can all get a reasonable gearbox upgrade solution for road and race car alike.
 
I know it's been a long time, but life unfortunately took over and I had to shuffle priorities to family.......... but just looking for something else and found out in the Quaife 2017 catalogue that they have part number E32G115 which is a bell housing for their QBE61G gearbox......... 6 speed sequential.......... http://quaife.co.uk/downloads/Quaife-Catalogue2017.pdf

It doesn't look like it's the right fit for the NSX which is confusing.......... not sure if anyone else has seen it........... they are offering helical cut gears too so would suit road use.....

Also as Integrals mentioned, I think Shad has a Holinger solution on a car.........
 
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