Quaife sequential,to clutch or not to clutch, that is the qu
Discussion
The new( to me ) R500 has the quaife sequential, I’ve had so many conflicting reports on gear changes and also coming from a 6 speeder where toe and heel downchanges are essential for track work it’s proving to be necessary to concentrate on breaking habits.
I’ve found that slight lift off is necessary for up change and though the box is reported to be immensely strong the noise on the down shift is alarming . Question is do or don’t clutch on the down change. I’ve spoken to some racers who don’t , but they don’t pay for the new boxes do they. Also surely clutching down with a blip must make it smoother surely.
Any advise gratefully received before I wreck the box or tear the diff out
Wahoo!
I’ve found that slight lift off is necessary for up change and though the box is reported to be immensely strong the noise on the down shift is alarming . Question is do or don’t clutch on the down change. I’ve spoken to some racers who don’t , but they don’t pay for the new boxes do they. Also surely clutching down with a blip must make it smoother surely.
Any advise gratefully received before I wreck the box or tear the diff out
Wahoo!
Normally you would use the clutch on a downshift if you don't have a paddle shift with the electronics and blippers to sort out rpm and timings. Most sequentials will have a flat shift to cut the engine and give seamless up shifts.
That said, I am sure there are those out there that have the skills to synchronize the throttle and allow it, but it only take a few bad shifts before it starts to get expensive.
That said, I am sure there are those out there that have the skills to synchronize the throttle and allow it, but it only take a few bad shifts before it starts to get expensive.
Why not ask Quaife? On their website they say:
“Sequential transmissions use dog engagement for ultra fast gear changes where a synchromesh engagement would not be fast enough. This allows gear changes to be made with very brief interruption of torque from the engine, which means changes can be made without the need to use the clutch.”
I’m sure they’ll tell you more if you call them.
“Sequential transmissions use dog engagement for ultra fast gear changes where a synchromesh engagement would not be fast enough. This allows gear changes to be made with very brief interruption of torque from the engine, which means changes can be made without the need to use the clutch.”
I’m sure they’ll tell you more if you call them.
REALIST123 said:
Why not ask Quaife?
Or possibly Hewland...Whether or not it's sequential, the technique and rationale behind changing gears on a dog engagement box is the same.
Chapter and verse is given under the FAQs on Hewland's website
Having raced a clio cup with a (stronger?) sadev 6 speed box, this had a cut for upshifts to allow flat shifting, but on downshifts you can either heel and toe with a tiny dip on the clutch, or just forgoe the clutch and heel and toe as required. All you need to do is apply a bit of "reverse torque" to unload the dogs. You shouldn't do any damage. I used to change the oil every race for the best EP silkolene we could get, and have the box inspected after 4 races. Never found any damage or particles, etc.
Unloading the dogs is the key. This is all an autoblipper does. You can do this with a quick H&T. It's a gearbox after all, not a meringue (although I can't vouch for any of Quaiffe's products as I've never used them). Warm it up and it should be fine. Decent oil is also your friend here.
Unloading the dogs is the key. This is all an autoblipper does. You can do this with a quick H&T. It's a gearbox after all, not a meringue (although I can't vouch for any of Quaiffe's products as I've never used them). Warm it up and it should be fine. Decent oil is also your friend here.
I have an R500 with quaiffe sequential box.
My top tips are as follows:
1. Full throttle upshifts work best with a slight lift, no clutch and firm pull of the lever. Gear goes in silky smooth and virtually seamless.
2. Part throttle up shifts work best with the clutch and be careful to try and match the revs to the best level for gear engagement to be smooth. This helps to mitigate the super loud clunking noIse which, however hard you try, cannot be completely eliminated
3. Downshifts - always use the clutch and heel/toe to rev match. Gives smoothest down shift but needs to be done accurately to avoid risk of locking the rears (particularly on track).
Overall, I love driving the sequential box. It takes practice to get it right, but when it clicks, it’s just awesome!! I would never trade down for a standard box.
Finally, I always use ear plugs because the box noise is really loud. However, it’s not a big problem on a long ‘cruise’ drive as 6th ratio is 1:1 and is therefore as quiet as any normal box.
My top tips are as follows:
1. Full throttle upshifts work best with a slight lift, no clutch and firm pull of the lever. Gear goes in silky smooth and virtually seamless.
2. Part throttle up shifts work best with the clutch and be careful to try and match the revs to the best level for gear engagement to be smooth. This helps to mitigate the super loud clunking noIse which, however hard you try, cannot be completely eliminated
3. Downshifts - always use the clutch and heel/toe to rev match. Gives smoothest down shift but needs to be done accurately to avoid risk of locking the rears (particularly on track).
Overall, I love driving the sequential box. It takes practice to get it right, but when it clicks, it’s just awesome!! I would never trade down for a standard box.
Finally, I always use ear plugs because the box noise is really loud. However, it’s not a big problem on a long ‘cruise’ drive as 6th ratio is 1:1 and is therefore as quiet as any normal box.
I used to work at Quaife and was on the design team for that gearbox. I also drove the demonstrator a few times.
As with any manually activated sequential gearbox the important thing is to be firm and positive when shifting. In full-power acceleration there really is no need to use the clutch, but when on part throttle, and when changing down the ‘box, a slight “dip” of the clutch is enough to match the revs during a change.
The ‘box is very strong, you’ll struggle to break it...
As with any manually activated sequential gearbox the important thing is to be firm and positive when shifting. In full-power acceleration there really is no need to use the clutch, but when on part throttle, and when changing down the ‘box, a slight “dip” of the clutch is enough to match the revs during a change.
The ‘box is very strong, you’ll struggle to break it...
OP just to add, I used to race a C400 with the same box and the way we used to do it was to apply a little pressure to the shifter and small lift for the upshift (it would drop in on mine as soon as you came off the throttle), clutch and heel-toe on the downshift. You could probably left foot brake and blip but i never tried it as my long legs aren’t conducive!
The Wookie said:
...the way we used to do it was to apply a little pressure to the shifter and small lift for the upshift (it would drop in on mine as soon as you came off the throttle), clutch and heel-toe on the downshift.
Yep, this is how I use to do it with Hewlands - the upshifts are as sweet an quick as anything (downshifts depend on how good you are at heeling-and-toeing, of course!).Going to book in at anglesey for the end of May holiday and start practising. I’ve always t&h on the 6 speeder so I guess it’ll be the same. Having only had the one outing so far it’s amazing how you have to concentrate on the shift pattern even though it’s only in one plane.
Thanks again all
Brett
Thanks again all
Brett
No, the 60G isn't much better. Caterham ditched them after they nearly ended the race series they were was used in due to reliability issues. That's why they moved to the Sadev, which with greater shaft centres and a conservative torque capacity of 265lbft is a different proposition.
Mr Carmichael had issues with the 26z in his car, and the one in Counts car too. I ditched it as soon as I bought that car.
Mr Carmichael had issues with the 26z in his car, and the one in Counts car too. I ditched it as soon as I bought that car.
Edited by Monsieur Du Lard on Sunday 24th June 08:59
Monsieur Du Lard said:
No, the 60G isn't much better. Caterham ditched them after they nearly ended the race series they were was used in due to reliability issues. That's why they moved to the Sadev, which with greater shaft centres and a conservative torque capacity of 265lbft is a different proposition.
Really? Thanks for the info 
The Wookie said:
Don’t know which was in my C400 but I think I was the only one who didn’t bust a gearbox in one way or another
Your C400 had a 60G in the end, but Caterham were early adopters with them (in desperation because of the issues with the 6 speed in a CSR) and there were a few issues with them then. They're still an agricultural pile of s
te imho, but they hang onto their oil a bit better these days, and people are less ignorant about maintainance, so they don't tend to st themselves that often now.sfaulds said:
Your C400 had a 60G in the end, but Caterham were early adopters with them (in desperation because of the issues with the 6 speed in a CSR) and there were a few issues with them then. They're still an agricultural pile of ste imho, but they hang onto their oil a bit better these days, and people are less ignorant about maintainance, so they don't tend to st themselves that often now.
It was bloody agricultural fauldsy that’s for surete imho, but they hang onto their oil a bit better these days, and people are less ignorant about maintainance, so they don't tend to st themselves that often now.Gassing Station | Caterham | Top of Page | What's New | My Stuff