The Gearbox..

[M@H]

OK I admit it.. I prefer the old one..!

With the early box, top gear was about 32-33mph per 1000 rpm so you could tick over at the speed limit around town and pull around 100mph at 3000 rpm.

The newer one seems to be 25mph per 1000 rpm instead which IMHumbleO seems a bit short for a lengthy GT cruise about on the motorway.

..is it just me..?

[AlexB]

How old is old?

I've just picked up my first TVR , ('95 Chimaera with 38000 on the clock - this should have the later 'box shouldn't it?) and other than the gears being a bit stiff (I'm told this is likely to get better after a good service) it's fantastic and as far as I remember it does about 70-80 at about 2500 revs so that looks like the ratio you give for the old gearbox! Seems to be very relaxed at that sort of speed.

Alex

[M@H]

Old is 93 94 ish... (who knows with TVR)

Basically the old box - reverse is left and forwards, new box, reverse is to the right and back.

Cheers
Matt

[AlexB]

Mine is the new box then.....don't remember it reving that high on the dual carigeway though.

Alex

[Stu247]

Back in the Chim fold again Matt !!

Well done that man...and a cracking one by the looks of things !! apart from the box

Stu.

[M@H]

Stu247 said:

Back in the Chim fold again Matt !! Well done that man....

Thanks I hope to get some pictures up soon.

..perhaps I'm driving it in 4th gear..

[the dodger]

I didn't think the gear ratios were much (if at all) different? I bet SH knows.........

Mine is a 94 with T5 box which gives around 27.5mph / 1000rpm in top [that's 5th Matt ] so cruising at 3k is a comfortable 80plus. Maybe you have the wrong diff?

[M@H]

..thats a point.. maybe there is a different diff in the later cars..?

as you say shpub will doubtless appear with all the answers soon I'm sure..

[Podie]

M@H said:

..thats a point.. maybe there is a different diff in the later cars..? as you say shpub will doubtless appear with all the answers soon I'm sure..

Early cars were GKN, later cars were BTR… IIRC...

[cosmoschick]

M@H said:

Old is 93 94 ish... (who knows with TVR)

Oi, stop calling Trevvie old!

I must admit I had to go and check the gear-lever to remind myself - anyway, it's right and back. So I guess he's not that old afterall!

[M@H]

Podie said:

M@H said: ..thats a point.. maybe there is a different diff in the later cars..? as you say shpub will doubtless appear with all the answers soon I'm sure.. Early cars were GKN, later cars were BTR… IIRC...

Indeed.. I meant that perhaps other tha nthe change when the gearbox changed in 94, was there a later diff only change in say 96-97..?

Am I going mad..?

Matt.

[Podie]

M@H said:

Podie said: M@H said: ..thats a point.. maybe there is a different diff in the later cars..? as you say shpub will doubtless appear with all the answers soon I'm sure.. Early cars were GKN, later cars were BTR… IIRC... Indeed.. I meant that perhaps other tha nthe change when the gearbox changed in 94, was there a later diff only change in say 96-97..? Am I going mad..? Matt.

A step between the Rover box and the T5..?

close ratio box..? As per the Cerbie…?

[M@H]

..not quite.. maybe same box but a different diff..(?)

[M@H]

OK i really don't get this...

The New BTR Diff has a final drive of 3.45 to 1, and the later BW T5 Box has a ratio of 0.8 to 1 in top. this would give 2760 rpm per 1000.

The Old GKN Diff has a final drive of 3.31 to 1, and the early LT77 Box has a ratio of 0.83 to 1 in top. this would give 2747 rpm per 1000.

So basically no difference.

.but the two cars are very different..?

Perhaps my old one had a different/modified diff.. aah well...

>> Edited by M@H on Tuesday 14th September 14:28

[.Markski]

Different speedo readings? Could one of them be slightly out?

[M@H]

They're probably all out to some extent ..although if AlexB is getting 80mph at 2500 that is the same as I *thought* my old Chim was doing (32mph/1000)