Front brake discs / bells / calipers - clarification thread

[Ireland]

I just spotted the new "large bells" thread as I've been away from the forum for a couple of weeks due to a death in the family.

The last day I was on we were still deciding what disc to use and see if one bell could be used for all.

Obviously not.

I've done a quick check and couldn't find any further discussion on this.

My car is currently on 16" rims so I'm stuck with having to use smaller discs for now.

However I plan to fit 18" rims to it so the bigger ones are obviously the way to go then.

I know Jools can get get bells made up to suit and the price seems fine for those.

What I'm not sure is .....

- did anyone find a definite source for bells?

- r8nan, did you get any more definite info on the larger calipers?

- itsallyellow did you get anywhere regarding the spacers to allow the larger calipers to fit the 4.2?

- what else did I miss ?

Sorry I wasn't able to help out with this over the last few weeks but obviously it wasn't top of my list of priorities but now I'm back and willing to help out however I can to get it sorted for once and for all.

[spitfire4v8]

yes i'm still going ahead with ordering bells for discs 310mm and over. someone else with a 4.2 would need to make a drawing for the smaller bells and sort that out, easy peasy for someone with CAD skills (which i dont have!)

[Ireland]

OK.

So it's just a case of sorting the calipers and spacers then for anyone who is changing to the bigger discs.

[Ireland]

I've PMd itsallyellow and r8nan and hopefully they'll post here before too long to clarify about the calipers and spacers.

[R8nan]

Hi Ireland

I have been working on this for the past couple of weeks. It did turn out to put on the larger discs I had to buy new callipers. As you know the standard 4.2 calliper only goes up to 304mm and that rotor does not fit the bell supplied by Jools.

To fit the 330mm rotor you need the larger calliper, either the original 6 bolt 4.5 calliper or the later calliper like I have went for. For each of these callipers you need spacers made up. Below is a picture of all the parts required, in the bottom right hand corner you can see standard spacers and you can see the difference between them and the new ones which are beside the calliper. Hope this helps, I am bolting everything on tomorrow.

[Ireland]

That doesn't look too bad.

I was expecting some odd-ball spacer for some reason, don't know why.

Let us know how it all works out.

By the way do both type of calipers use the same pads?

[Demondad]

Can you give an itemised break down of costs and suppliers for this kind of set up. Mines a 2003 4.2 discs on the way out.

[Ireland]

We are awaiting r8nan's feedback on how he got on fitting his.

He sourced all the bits from various places.

I'll PM him and see if he has it done and how it went.

[R8nan]

I have just finished upgrading the brakes, it did turn out to be a little more difficult than I thought mainly down to getting the correct size spacer made up.

So here goes with all the details and prices.

Brake Bells Jools £136.00 if you are in group buy

Brake Rotors
Ref CP3580-2898G8 R/H 330 x 28 Disc
Ref CP3580-2899G8 L/H 330 x 28 Disc
Ref CP3845-100K Bolt Kit x 2 BG Developments £453.34

AP Calliper (Later design)
Ref CP 6600 - 3SO
Ref CP 6600 - 2SO Ebay Seller £300.00 Phone for this price


AP Brake pads BG Developments £100.00

Calliper Mounting bracket spacer. Local Frabricator £150.00 If anyone is interested in buying one of these he would do them for £120 five or more. It did take a lot of time to get exact measurement.

Hope this helps. I will post some pics tonight to let you all see them installed.

[dean_ratpac]

im looking at putting a group buy together for the rotors if anyones interested. i'vetried to get hold of the J-Hook design (only available in floating format) so curved group and should be able to save some $$

[R8nan]

As promised here's a pic of the new brake set-up

[RichV6]

I take it thats the equivilent of the 4.5 set up. Therefore it
should fit inside the standard RL7 17" wheel.

[B16 VRM]

R8nan, have you tested your new setup. Is it a big improvement over the standard 4.2 setup. I would be definately interested in getting a set of spacers as you have kindly paved the way.

[R8nan]

RichV6 said:

I take it thats the equivilent of the 4.5 set up. Therefore it
should fit inside the standard RL7 17" wheel.

Its slightly bigger than the standard 4.5 set up, but I would be fairly sure they could fit under the RL7 17" wheel. You could also just buy the standard 4.5 rotars if you needed more room.

B16 VRM said:

R8nan, have you tested your new setup. Is it a big improvement over the standard 4.2 setup. I would be definately interested in getting a set of spacers as you have kindly paved the way.

I have tested the setup fairly well now. I did do a few miles just to get the pads bedded in, but now the whole thing is working very well. The braking is very smooth and gives rapid stopping power. Very pleased

[RichV6]

Thanks for that, away from home at the moment but have managed to download
a load of info from AP, only thing I don't have is the inside dia of an RL7.

As soon as I'm sure it will all fit I'll order more bits.

[Erich Stahler]

spitfire4v8 said:

yes i'm still going ahead with ordering bells for discs 310mm and over. someone else with a 4.2 would need to make a drawing for the smaller bells and sort that out, easy peasy for someone with CAD skills (which i dont have!)

Surely the diagrams on pages 4 & 5 of the TVR factory service manual gives you the dimensions of the hub and calliper that you would need to have the 4.2 bells manufactured?
http://www.tvr-cerbera.co.uk/files/WorkshopManual/...

Edited by Erich Stahler on Friday 21st August 18:12

[Allandwf]

Are we any further forward with direct bolt on replacements for the 4.2. (294mm disc , I think.)
It's not as if there isn't a market. Personally I'd just like a straight replacement for my disc without having to go for bells, rotors, caliper replacement. I see no reason to upgrade mine as the standard brakes are probably the best I have had.

[RichV6]

Sorry for the return of an old thread, but have just finished the fitting
of the new calipers and the discs and bells previously collected over the last few months.
For those who are interested theres masses of room inside a 17" RL7 for the 330mm discs
and CP6600 caliper, to the point that the next size disc up would fit.

Thanks to r8nan for the spacers and Joo for the bells, just need better weather to
bed in and test.

[900T-R]

If anyone got a pair of 4.2 callipers going spare I'd be interested - for development purposes.

[TT Tim]

Thanks for reasurrecting this thread as it's on my to do list.

Does anyone know what else I'll need to fit 'floating' discs, is it just different bobbins?

Looking at these disks which are same spec as the others: click here

Thanks for the help.

Tim