Front Brake Calipers & Diff

[Seabass]

I'm currently working from a bare chassis up to get my Vixen S3 rolling. When I got the car it did not come with front brake calipers or a diff.
I have just about figured out that Girling 16PB calipers were fitted but have read elsewhere that the metric M16 calipers may also fit. If that is the case then before I shell out large sums for iron calipers could I look at moving to equivalent M16 alloy calipers for not very much more money?
Secondly the diff - I have been reading around this and many claim the spitfire 1500 diffs have the stronges crown wheel and pinion, either in 3.89 or 3.63 ratios. Are these a straight swap for the GT6/Vitesse unit??
I sure these are classic TVR noob questions but I have to start somewhere. Advice greatly appreciated. James

[Adrian@]

Original fitting should of been 16P calipers, to retro fit 16PB is a bolt change from the 5/8 head bolt to the later 3/4 headed bolt, which has a special shank to suit the 16 PB/M16, but with the same 7/16 unf thread in the hand, AND then a flexi hose change to suit the metric caliper. The diff issue has nothing to do with the crown wheel and pinion, more that the casing has better and strong internals (you cannot tell from the outside). Over the years this is the most popular part to be 'LOST' when the differential is reconditioned, as the rebuilders know that they have a 'value' and also, that the top mounting bolts are not used when it is fitted to a TVR (these break off in the Triumph) they see the exchange as an easy way to get hold of the stronger diff casing.
Adrian@

Edited by Adrian@ on Friday 19th October 18:40

[Seabass]

Thanks for the reply Adrian.

So the original fit is early TR4 16P calipers? Your confusing me a bit with the 16PB/M comment. According to my understanding 16PB is still imperial (flexy and bleed wise) and the M16 caliper is metric. Do M16 calipers fit or is the lug spacing different?

I understand the diff comments - sneaky rebuilders eh?

James

Edited by Seabass on Friday 19th October 19:25

[Adrian@]

[quote=Seabass]Thanks for the reply Adrian.

So the original fit is early TR4 16P calipers? Your confusing me a bit with the 16PB/M comment. According to my understanding 16PB is still imperial (flexy and bleed wise) and the M16 caliper is metric. Do M16 calipers fit or is the lug spacing different?

I understand the diff comments - sneaky rebuilders eh?

James

The 16PB is normally metric flexi and bleed M10x 1.5 (but there is a crossover caliper that has the later type piston/seals and imperial fittings) I build all 3 versions for TVR's .....You mention TR4, but then I have never worked on a TR4, but understand that they had the thinner disc, and so I presume a matching caliper. The way I denote the TVR caliper is on retaining pin size 1/4 imperial and 3/16 metric. I cannot answer the M16 question for fitting as a fact but I presume that it is the same spacing.
Adrian@

Edited by Adrian@ on Friday 19th October 22:57