Caterham 6-Speed Gearbox Article

[scudracer]

http://www.sevenbuilder.com/id/137/c...speed-gearbox/

A friend of mine wrote the article linked above ... what do you guys think? Is it accurate? Any mistakes?

[magnusfeuer]

That's some nice background info on the box.

Although the article states that the old T9 box had the best ratios, first gear is still useless since it is so short. The wide ratio difference between first and second makes that shift into an eternal synchro-ring battle. On the flipside, though, the box is more or less indestructible.

I personally love my Caterham box, although I am still bleeding from the expense. It literally transforms the car into something much more nimble, for example when you take off from the sunset corner to the main straight at Buttonwillow (http://www.buttonwillowraceway.com/i...01_config.gif), and fly through the gears without even thinking about it. Toe-and-heel downshifts are also done without a second thought to speed or rpm. You just blip the throttle and throw in the next gear down. Lovely!

/Magnus F.

[magnusfeuer]

Scary crash video at the http://www.sevenbuilder.com/ site, though....

/Magnus F.

[Elv15]

Good thing that guy had a cage!!!

[Sean-og]

After reading one of the other threads, I think maybe Michael and Chris might want to get together with their respective proctologists and watch that video. :D
http://www.californiacaterhamclub.co...read.php?t=828

Sorry Michael and Chris; I have never even met you guys, or your proctologists, but I just couldn't resist! :)

[moosetestbestanden]

That vid has been often discussed on BC for a while now. I sort of expected to see something similar at Donington but, while there were a few, um, exciting moments there was nothing quite so dramatic as that roll.

But, back OT...

The ratios in the T9 can be changed. W/ the torque of the Duratec, a H pattern 5 speed Quaife dog box is where I'll be headed someday, w/ a looong 1st stepping to an overdriven 5th. And then someday after that someday a sequential shifter maybe.

[JohnCh]

I just updated to a long 1st gear BGH box (running a 3.62 rear end). Having a usable 1st gear and a small gap to 2nd really transforms the car.

-John

[moosetestbestanden]

I just updated to a long 1st gear BGH box (running a 3.62 rear end). Having a usable 1st gear and a small gap to 2nd really transforms the car.

-John

My discussions w/ Roger Swift led me in this direction. Good to have it affirmed by another. Thanks John.

Edit: Hmmm, the Caterham 6 speed is significantly less expensive than a Quaife. So, Magnus, what are the ratios? CC's website doesn't say

[Roll a 7]

2.69:1, 2.01:1, 1.59:1, 1.32:1, 1.13:1, 1.00:1

[Roll a 7]

The guy in that video should invite all of his 7er freinds to a party to view the video. Party theme: CrashBash!!

[magnusfeuer]

When I bought the 6-speeder I also opted for the 3.38 limited slip diff since I (correctly) speculated that it would fit my supercharger's low end torque profile better. The first gear lasts for ever but is not so tall that I drop out of the torque curve when doing hairpin turns.

The new Duratec engine should be fine here as well since the CSR, which has the same engine (minus the fancy roller bodies), runs 3.38 as well.

/Magnus F.

[scudracer]

Is BGH the supplier who had problems with Caterham, and then was dropped from the project? No one seems to be mentioning it in the books.

Yes Magnus, that crash makes me think that a cage should be mandatory for all Sevens!

[moosetestbestanden]

The new Duratec engine should be fine here as well since the CSR, which has the same engine (minus the fancy roller bodies), runs 3.38 as well.

Yeah. You may be rowing more than w/ a 5 speed but that's part of the fun.

I rode w/ Pierre at Buttonwillow and observed the dog at work. I liked it. Less mechanical drag as well, or so it says. Besides, that way one could do this here:

http://www.7tips.co.uk/7tips_site/Pembrey_Video.html

Watch the lever moved by a ghost's hand:D

[magnusfeuer]

Chris,

You realize you will need a Pectel T6 or equivalent ECU for that one which can blip the throttle on downshifts and retard the ignition on upshifts. You buy the box, I'll do the programming.

/Magnus F.

[moosetestbestanden]

I'm not really going to go there - matching revs & rowing is too much fun. But it does look kind of spooky:D