6 speed box

6 speed box

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Discussion

IPAddis

Original Poster:

2,471 posts

284 months

Thursday 17th October 2002
quotequote all
Has anyone actually fitted a 6 speed gearbox to a Chimaera or Griffith? I seem to remember someone saying that a Borg Warner T55 would fit given some persuasion.

I know someone has managed to fit a sequential box but that is probably a bit extreeme for road use (I presume you have to go through all the gears to get to neutral).

Just something else that I could add to my wish list.

Ian A.

zertec

499 posts

283 months

Thursday 17th October 2002
quotequote all
I think the correct designation is T56

IPAddis

Original Poster:

2,471 posts

284 months

Thursday 17th October 2002
quotequote all

zertec said: I think the correct designation is T56


That's the badger. Does it fit?

dannylt

1,906 posts

284 months

Thursday 17th October 2002
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Don't think so. Besides, with the torque from the Rover, is it really worth while?

Leadfoot

1,901 posts

281 months

Friday 18th October 2002
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That's the box from the Corvette isn't it? Geared to somefing like 220 mph in top if it is = overdrive

IPAddis

Original Poster:

2,471 posts

284 months

Friday 18th October 2002
quotequote all

dannylt said: Don't think so. Besides, with the torque from the Rover, is it really worth while?



It stops you having to run at 3000+ rpm on the motorway (err... which is actually 90mph, let's say on a track) when the engine would happily pull you along at the same speed at 2000rpm given an additional gear. The savings in fuel alone...

davidd

6,452 posts

284 months

Friday 18th October 2002
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Hmm a high 6th gear would be great in the Cerbera, I might get 19mpg then

D.

hexhamhc

456 posts

283 months

Friday 18th October 2002
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I believe that the box currently fitted is the Borg Warner T55 (I assume 5 for five speed) There is a six speed version available called unsuprisingly the T56. I did some research on this as I too thought it might be a useful conversion, however the box's dimensions at some 8" wider means that there is simply not enough space in the chassis to fit one. TVR's own compact six speed sequential box may not be too far away now and I'm sure that'll fit!

TR MIKE

21,188 posts

260 months

Friday 18th October 2002
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PaulU and I reckon it will fit and may be doing it soon. The box doesn't seem to be much bigger in any overall dimension, it's just pumped up on steroids all the way down it's length. It's quite heavy at appx 8.5 stone. A T5 would maybe be more suitable up to 350 bhp. Bigger engines or those with forced induction may benefit from the T56.

dannylt

1,906 posts

284 months

Saturday 19th October 2002
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Why 350bhp? I thought gearboxes were rated for torque, not power. In any case, I thought it was rated for 400+ lbft, so the T5 should be have plenty of margin.

VictorMeldrew

8,293 posts

277 months

Saturday 19th October 2002
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A higher top ratio might be a mixed blessing. Yes, it would drop the revs for motorway cruising, and along with that the noise and consumption, but ... well, 80mph seems a natural cruising speed on the standard ratios, don't you think? I used to wonder why TVR owners cruised at that speed until I got one. Any faster is just too busy - twitchy and noisy.

Stick in a longer legged box and comfortable cruising speed might become uncomfortable on the licence if you know what I mean.