CSR260 Sequential Box

[Steve Cowley]

Decisions, decisions. 6 speed vs sequential in a CSR260.

Love the sequential box in my SR3, and in the Ginetta, but that's full time track. This will be sunny days in the back country and track days.

How loud is it? Do you really need to be at full chat to shift up or it baulks? Could become tiresome. Is it a Quaife box? Does it come with a reverse?

All opinions from those who've experienced it are very, very welcome.

Thanks

[Croc]

Before I finalized the spec on my CSR I drove two in the UK - both a 6 speed (curvy dash) and a sequential (traditional dash). So my experience may have been adjusted given I was driving two used cars with over 10,000 miles on the clock. To answer your questions:

How loud is it?

It is notably more whiney than the regular 6 speed. Sounded like the gears were straight cut rather than the helical style - relative comparison for noise between the 6spd and sequentiual. For a short drive I was not worried but on a long cruise it could get annoying. I use ear plugs anyway so noise was not a major factor for me not spec'ing it.

Do you really need to be at full chat to shift up or it baulks? Could become tiresome. Is it a Quaife box?

At least what I drove was a Quaife box. To get the car moving from standstill you have to slip the clutch a lot - this is a problem as I have a lot of traffic lights to navigate near my home before I can escape to better roads. It was ok shifting up at around 3500-4000rpm and higher, obviously higher the revs the better. However, it was not a happy thing shifting under 3000rpm. In my 6 speed car, when I am back road cruising with low speed limits I will often shift at 2000-2500rpm and use the torque to pull me along. That is not an option with the sequential.

I decided it would end up being a pain in the a#$ and so stayed with the 6 speed box. The guys at Caterham USA were unanimous to me about going with the 6 speed and not going for the sequential. I have not regreted that decision as it suits my mix of backroad twisties, interstate transits to good roads and the oddly frequent track day.

If I was going to get a sequential I would go for the Sadev. A lot more expensive but beautifully built. There is one in a Cosworth Duratec SV near me. Buttery shifts on demand. Still need lots of clutch slip to get going from standstill so not ideal around traffic/high density areas.

Does it come with a reverse?

I understood it does but I never used it on my UK test drive - forward motion only.

[Roll a 7]

You might also consider the Caterham 6 speed trans. It is a bit noisy and may not have an overdrive 6th gear, but still works great. Quite a few around if you want to try one.

[moosetestbestanden]

If I was going to get a sequential I would go for the Sadev. A lot more expensive but beautifully built. There is one in a Cosworth Duratec SV near me. Buttery shifts on demand. Still need lots of clutch slip to get going from standstill so not ideal around traffic/high density areas.

Is that because it's a sequential or because it has a tall 1st ratio?

On another note, I've made marvelous photographs of a destroyed center tunnel & drive shaft u joint in a car fitted w/ a Quaife sequential. Nothing wrong w/ the transmission mind. The disaster was a result (most likely) of the car not having an electronic ignition interrupt fitted to the car. Direct drive shock gear changes eventually blew the front U joint to bits, causing major spinning - flapping driveshaft damage to everything except the driver's right leg (fortunately).

For the record, the last time I checked that particular gearbox sounded like a box of Cracker Jacks (again, no fault of the gearbox) and the car was not moving anywhere.

[magnusfeuer]

If that is the box I think it is, I completely agree. The guy was lucky that the prop shaft took out the passenger seat and not his legs. Hot, high-quality slicks and no ignition cutout switch on the stick means that the torque shock has nowhere to go on up shifts.

Apparently the car had half shafts for breakfast as well.

/Magnus F.

[sdcat]

Sorry to change the subject, but do you have a Ginetta here in the US Steve? What model? I would love to have a G20 if they were licensable here.

p.s. I ordered a Sadev myself last month. I don't know much except what I've read and heard, but it seemed a good choice. You are welcome to try it once it is in the car.

Justin

[Croc]

Is that because it's a sequential or because it has a tall 1st ratio?

Chris - Its because it is sequential. First gear ratio is the same as the Caterham 6 speed.

[Steve Cowley]

Justin, I raced the Ginetta in the GT3 Middle East championship when I lived there. I recently moved from Dubai to the USA. Here's a lap http://www.youtube.com/watch?v=yHRtcVttJmY

and another lap http://www.youtube.com/watch?v=3yp4rlviuQU with a some fun @30 secs as I nearly learned the hard way about getting big slicks up to temperature :-)

Thank you for the offer. There's a bit of hating going on at USA7's about sequential boxes in a CSR260. I'm not keen to spend 7k on a box which is then either not warranted / consumes itself / is noisier than the pipe itself / unusable except at peak revs etc. All of which I've been told.

Steve

[Doug Liedblad]

Chris - Its because it is sequential. First gear ratio is the same as the Caterham 6 speed.

Please help me understand how the sequential needs more clutch slipping than a tall first 5 or 6 speed box? I can understand it if the 1st gear along with the diff ratio is really high but don't understand how the sequential itself makes a difference.

Perhaps it had a competition type clutch where it's essentially engaged or disengaged with not much allowance for slipping.

Thank you.

Doug

[sdcat]

Steve, Great videos - looks like you probably have a much better sense of what a sequential would be like than I, since you've raced with them. Through the info I've gotten from people who've used the quaife, I can understand the downsides of putting one in a street car. I have heard better things about the Sadev, though, and my use for the car is 90% track time. I've done over 30 track days in the past two years in it, and plan to do continue to get out at least once a month. Karl is of course the one I would listen most to since he has one, and he summed it up pretty well in his post on USA7s.

Doug, I wonder the same - we will be putting a different clutch in with the Sadev, so maybe that is the reason for the more difficult start in first gear.

[Croc]

Please help me understand how the sequential needs more clutch slipping than a tall first 5 or 6 speed box? I can understand it if the 1st gear along with the diff ratio is really high but don't understand how the sequential itself makes a difference.

Perhaps it had a competition type clutch where it's essentially engaged or disengaged with not much allowance for slipping.

Doug - As I understood it, Caterham spec a different race-type clutch for the Quaife sequential than the regular 6 speed box. I asked if they would fit the regular clutch with the Quaife but they said no as durability was a major problem, even if not in a race series environment. I really did not get into any more specifics as that was enough for me to make a decision to go for the 6spd H pattern gearbox. Your theory on the competition clutch makes most sense to me.

I have heard better things about the Sadev, though, and my use for the car is 90% track time. I've done over 30 track days in the past two years in it, and plan to do continue to get out at least once a month. Karl is of course the one I would listen most to since he has one, and he summed it up pretty well in his post on USA7s.

Karl is a track rat with his car so a sequential makes sense (well not to his wife it did not! ) PM him on USA7s and talk to him by phone if you want a better feedback - he is a good guy to chat with. Having been with Karl's car on backroad drives and on track, I am convinced the Sadev is a good piece of equipment.