Talk Diffs

[ChazUwe]

I have done a fair amount of searching but would appreciate some confirmation. Are all the 3 original diff options supplied by Hydratrak? Reason I ask was that I was getting the wheels off to give them a good clean and spotted this sticker on the diff:



Some of the posts I have read suggest the Hydratrak LSD is the 3.73 ratio, but I have read another thread that says all the diffs have a hydratrak sticker but will have the ratio noted somewhere else on the diff? Just wondering what I have, no mention of the Hydratrak as an option on the buildsheet.....

Anyone?

[chris watton]

This is the tag on my old (non Hydratrack) diff:

[ChazUwe]

Thanks Chris, where is that tag located when the diff is installed. Is it easy enough to access from underneath?

[chris watton]

I think that is the rear left side, near the speed transducer bracket.

[ChazUwe]

Great, will check it out tomorrow to see if I have one of those tags. Should be more definitive!

[twinreal]

Have a hydratrak with ratio 3.49, so i assume this was an option and TVR fitted what was lying around.
EDIT: meant 3.46

Edited by twinreal on Wednesday 26th August 17:23

[ChazUwe]

Couldn't get a decent picture but I have confirmed that mine is infact a 3.45 ratio. It has a part number of R0077 but can't seem to find any info about it. Part no R0076 is not a hydratrak so not really sure!

[chris watton]

And the manual states that it should be a 3.73!

From what I have read and researched on here, the best combination is a CR box with a 3.73 diff. Some will argue that the 3.91 is better, but I have spoken to a Tuscan owner who hates it, and wants to change to 3.73 for slightly less noisy motorway journeys (but others swear by it, for balance)

[8nil]

I had a Hydratrak with a 3.45 ratio and have the CR box.
However I have just had the diff rebuilt with a Quaife ATB.

The 3.45 ratio and the CR box are a decent enough match, but the lack of torque lowdown on the 4.0 means, it doesn't pick up as well as 3.73.

The 3.91 ratio will do your conkers in on a long journey (personal opinion!)

[ChazUwe]

So the Hyrdatrak came in at least the 3.45 and 3.73 ratio's? So looks like I do have a Hydradrak with 3.45 a ratio... Happy with the combo at the moment, but I do hear that some say standard gearbox and the 3.73 gives a bit more poke! Could be tempted next year

[anonymous-user]

ChazUwe said:

So the Hyrdatrak came in at least the 3.45 and 3.73 ratio's? So looks like I do have a Hydradrak with 3.45 a ratio... Happy with the combo at the moment, but I do hear that some say standard gearbox and the 3.73 gives a bit more poke! Could be tempted next year

3.73 will feel like it's got more get up and go compared with the 3.46.

3.73 and CR is heaven, 3.91 and CR is not to everyone's taste, but for track work it's awesome. 3.46 and CR is dreadful....(sorry but it's a fact)

[ChazUwe]

Might consider the change to the 3.73 next year. Going to the south of France in September which will be my first long slog in the T350. Will see how I find prolonged 80-90mph cruising! Thanks for all the advice!

[Lotus E300S]

Wouldn't bother with a Cr box myself, makes first 2 gears far too long, driven them all now and standard box 3.7 diff feels best IMHO with standard engine.