Close Ratio Gearbox missing

[R11ysf]

From doing a search and reading previous posts it seems that as the last Tuscan 'S' models left the factory they got whatever gearbox was sitting around. I'm going to look at one which doesn't have the close ratio gearbox.

So the questions are:
a) is this important
b) what is the cost of replacement (someone mentioned £2,500 from TVR power??)
c) is this something that would stop you getting this particular one?

From what I've read a CR box with the limited slip diff does give a noticeable performance gain, not to mention 100mph in 2nd gear! Something worth having I reckon.

Can anyone please tell me from experience their thoughts.

Thank you.

[TVR_owner]

R11ysf said:

From doing a search and reading previous posts it seems that as the last Tuscan 'S' models left the factory they got whatever gearbox was sitting around. I'm going to look at one which doesn't have the close ratio gearbox.

So the questions are:
a) is this important
b) what is the cost of replacement (someone mentioned £2,500 from TVR power??)
c) is this something that would stop you getting this particular one?

From what I've read a CR box with the limited slip diff does give a noticeable performance gain, not to mention 100mph in 2nd gear! Something worth having I reckon.

Can anyone please tell me from experience their thoughts.

Thank you.

Very few of the later budget S cars that were built have CR boxes. Is it worth the change, depends really.

Need to look at final drive first up, if its a 3,46 a change to CR without a diff ratio cchange is a huge backward move. If you want to go CR after you discover the diff ratio is wrong (3,46), then you will need to weigh up 3,73 or 3,91.

A box and diff change should cost no more than £2500.

When the Sagaris came out, many who drove them said they were slower than the Tuscan S - the reason being gearbox and diff combinations.

If it were my choice, and the existing kit had done some miles, I would go CR and 3,91 - it's a ballistic combination.

[R11ysf]

Thanks for that.
So forgive my stupidity, there are 3 diffs and 2 boxes. If it is not a CR box what is the best diff to have?
What difference does a 3.46 diff to a 3.91 actually mean? More revolutions have to be put out by the 'box to get the wheels to turn the same?

Sorry for stupid questions, just presume I know nothing!!

Thanks

[glow worm]

The story I got from John Reid was they couldn't get hold of "a pinion" (IIRC) that was required for a 3:73 diff, and the combination of 3:46 with a CR box was awful.So the decision was made NOT to supply Tuscan S's with CR boxes , although the spec sheets for the Tuscan 'S' cars say they should have them. The standard spec sheets for Sags in 2005 a CR box was a chargeable option at £1,530. Visually, the only way to tell is if John Reid wrote CR on the gearbox.
I've changed my diff to 3:73 when I had a shortened prop shaft put in , to stop the "shunt" and I think it drives loads better now.
Oh, I also changed to the older 4 flange diff from the three flange.
That's when I have a break from polishing it

I thought one main reason for a CR box was to get a sub 4 sec time for 0-60 (in 1st) and 0-100) in 2nd...something I don't do very often

Edited by glow worm on Tuesday 9th February 19:09

[Targarama]

R11ysf said:

Thanks for that.
So forgive my stupidity, there are 3 diffs and 2 boxes. If it is not a CR box what is the best diff to have?
What difference does a 3.46 diff to a 3.91 actually mean? More revolutions have to be put out by the 'box to get the wheels to turn the same?

Sorry for stupid questions, just presume I know nothing!!

Thanks

Your engine will be spinning at higher revs for each mph you move forwards. The Speed Six makes more power and torque as you increase the revs (unlike a Rover V8 which flatlines). Diff ratio change helps put the car more 'into the zone' more of the time. Do a search, lots of topics on this on the T350/Sagaris forum.

[willtvr]

A good compromise if you don't want to go to the expense of the c/r box is the 3.73 diff. Sharpens up the acceleration and still gives you about 25mph per 1k rpm.

[kcc]

TVR_owner said:

R11ysf said:

From doing a search and reading previous posts it seems that as the last Tuscan 'S' models left the factory they got whatever gearbox was sitting around. I'm going to look at one which doesn't have the close ratio gearbox.

So the questions are:
a) is this important
b) what is the cost of replacement (someone mentioned £2,500 from TVR power??)
c) is this something that would stop you getting this particular one?

From what I've read a CR box with the limited slip diff does give a noticeable performance gain, not to mention 100mph in 2nd gear! Something worth having I reckon.

Can anyone please tell me from experience their thoughts.

Thank you.

Very few of the later budget S cars that were built have CR boxes. Is it worth the change, depends really.

Need to look at final drive first up, if its a 3,46 a change to CR without a diff ratio cchange is a huge backward move. If you want to go CR after you discover the diff ratio is wrong (3,46), then you will need to weigh up 3,73 or 3,91.

A box and diff change should cost no more than £2500.

When the Sagaris came out, many who drove them said they were slower than the Tuscan S - the reason being gearbox and diff combinations.

If it were my choice, and the existing kit had done some miles, I would go CR and 3,91 - it's a ballistic combination.

Are the 4.3 upgrades different as i though G V was advised a 3.73 with a CR.

[TVR_owner]

Ken,
The 4,3 makes its power differently and I see no benefit from going to 3,91 - I belive a 3,7 would be ideal.

[GT TVR]

Can confirm that a CR box with 3.91 diff is a great combination.

[pete]

I've got a 3.73 in my Tuscan 3.6, and it's the major contributory factor in everyone who has driven it being amazed that it feels so quick. That's with a normal, wide ratio box. A friend's Tuscan Red Rose with a 3.46 diff and CR box feels sluggish off the line by comparison, although it will hit 100mph with only one gear change!

I'm just in the process of upgrading to a 4.3, and Dom's advice was to stick with the standard ratios and the 3.73. Sure, a CR box would be nice, especially with all the extra torque, but the diff seems to make the major difference in the real world.

Pete

[R11ysf]

So having read this and a few other threads is it right to say that for a Tuscan S without a CR box it is best to have a 3.7.3 or 3.91 diff?

What should the limited slip Hydratrak 'S' diff have been?

[glow worm]

May depend when ??? But certainly laterly on MK2s....What was available at the time...So they could get the customers money as quickly as possible. ...

I could tell you the butchered bits I got on mine.Including Griff sidelights...

Edited by glow worm on Wednesday 10th February 19:19

[GT TVR]

R11ysf said:

So having read this and a few other threads is it right to say that for a Tuscan S without a CR box it is best to have a 3.7.3 or 3.91 diff?

What should the limited slip Hydratrak 'S' diff have been?

I think ideally it's standard box with 3.73 and CR box with 3.91.

[Ubernoober]

GT TVR said:

R11ysf said:

So having read this and a few other threads is it right to say that for a Tuscan S without a CR box it is best to have a 3.7.3 or 3.91 diff?

What should the limited slip Hydratrak 'S' diff have been?

I think ideally it's standard box with 3.73 and CR box with 3.91.

Standard box and 3.73 diff on my late T2S - good for around 85mph in second and 27mph/1000rpm or so in 5th.

[Targarama]

R11ysf said:

So having read this and a few other threads is it right to say that for a Tuscan S without a CR box it is best to have a 3.7.3 or 3.91 diff?

What should the limited slip Hydratrak 'S' diff have been?

On a 3.6/4.0L I think the only thing to avoid (or upgrade as first change to the car if buying) would be a CR gearbox with either a 3.73 or 3.91 diff ratio. All ratios work fine on a standard box.

The other thing to consider is if you have a 4.3 engine the much torqueir power delivery means you may not need to go to 3.91, just 3.73.

[GT TVR]

Targarama said:

R11ysf said:

So having read this and a few other threads is it right to say that for a Tuscan S without a CR box it is best to have a 3.7.3 or 3.91 diff?

What should the limited slip Hydratrak 'S' diff have been?

On a 3.6/4.0L I think the only thing to avoid (or upgrade as first change to the car if buying) would be a CR gearbox with either a 3.73 or 3.91 diff ratio. All ratios work fine on a standard box.

The other thing to consider is if you have a 4.3 engine the much torqueir power delivery means you may not need to go to 3.91, just 3.73.

Eh, don't think so. I think the one to avoid is the 3.46 diff, for all boxes. 3.73 and especially 3.91 work very well with a CR box.

[Targarama]

GT TVR said:

Targarama said:

R11ysf said:

So having read this and a few other threads is it right to say that for a Tuscan S without a CR box it is best to have a 3.7.3 or 3.91 diff?

What should the limited slip Hydratrak 'S' diff have been?

On a 3.6/4.0L I think the only thing to avoid (or upgrade as first change to the car if buying) would be a CR gearbox with either a 3.73 or 3.91 diff ratio. All ratios work fine on a standard box.

The other thing to consider is if you have a 4.3 engine the much torqueir power delivery means you may not need to go to 3.91, just 3.73.

Eh, don't think so. I think the one to avoid is the 3.46 diff, for all boxes. 3.73 and especially 3.91 work very well with a CR box.

OK, I mixed myself up. Let me try again:

On a 3.6/4.0L I think the only thing to avoid (or upgrade as first change to the car if buying) would be a CR gearbox with a 3.46 diff ratio. All ratios work fine on a standard box.

The other thing to consider is if you have a 4.3 engine the much torqueir power delivery means you may not need to go to 3.91, just 3.73.

Edited by Targarama on Thursday 11th February 13:21

[GT TVR]

I hear that a standard box with 3.46 diff isn't too great either, so better to avoid the 3.46 in any case.

[JR]

GT TVR said:

I hear that a standard box with 3.46 diff isn't too great either, so better to avoid the 3.46 in any case.

Unless you have the 4.3 as a tourer.

[Targarama]

GT TVR said:

I hear that a standard box with 3.46 diff isn't too great either, so better to avoid the 3.46 in any case.

Well the 3.73 and 3.91 are better as the engine is closer to/more in the power band, but like I said most cars come out of the factory in this configuration.