Griff 430 Brake Upgrade

[adamhutcheson]

Hi, I have recently acquired a Griff 430 1992 model with the original TSW split rim alloys.

Can I have some pointers regarding an upgrade to the brakes. I do not intend to track or race the car, I would just like a bit more stopping power as the stock items are a little vague. Can I just upgrade the front brakes, as I assume they do the bulk of the work?

Thanks Adam

[Jay Ayegees]

Hi Adam

The split rims are by OZ Racing.

I upgraded my Griffith 4.3 brakes - 300mm vented discs with Wilwood Super Lite 4 pot calipers on the front and later Griffith 500 vented discs and calipers on the rear - now very good balanced braking.

Jay

[barreti]

Do those wilwood superlites go behind your 15" rims OK Jay or have you changed your wheels too?
Strangely enough, I was trying to get exactly this information on the Chim forum earlier this afternoon.

Does anyone know if there's a difference between the calipers on the earlier 4.x cars than on the 500s ?
I know the rotors are different but a guy on ebay tells me they are the same but I am convinced I've read they are different and putting on 500 calipers and rotors is an upgrade for the 4.x cars

Edited by barreti on Tuesday 24th April 17:52

[Jay Ayegees]

Hi Barreti

Sorry I have 16"s front and rear so not sure if they will fit behind 15"s.

The 4.x Griffiths have smaller front and rear calipers and discs to the 500s - to fit the 500 rears I fitted the 500 hubs as well.

Jay

[nicbowman]

Cheapest is Sierra Sapphire cosworth 4wd calipers, and 2wd discs, £300, need to use e bay though for the calipers.

Only the front has been modified. They work really very well and the balance is fine.


Nic

[350matt]

The original 4.x set-up is 240mm discs whereas the 500's used 260mm discs with a slightly bigger caliper, one of the cheapest mods is fitting 283mm discs off a 2wd sierra cosworth and either space the existing calipers out to suit or fit the calipers from a Granada cosworth which are the same piston size but will bolt on with no spacer / bracketry required.

As the original set-up puts too much brake bias towards the rear this mod also makes the car more stable under heavy braking and less inlcined to swop ends when braking with some steering lock on


Matt

[spend]

If you are going from solid disks to vented disks the calipers are different. The carrier is also different IIRC, I guess most people just bought complete uprights rather than splitting wheel bearings.. ETAn about rears BTW

I think there have been comments about the willwoods interfering with balancing weights on 15" wheels..

Dave

Edited by spend on Tuesday 24th April 19:06

[barreti]

Thanks for all that 350matt, a great help.
Does it make that much difference just to put on bigger disks without changing the calipers then?
Blimey, theres a pair of granny cosworth calipers on ebay now. £250 sound about right or what?
If I wanted to keep the original calipers and space them out to fit the 283mm disks what would you make the spacers out of, and do they need to be one piece like I've seen on calipers for sale or are they essentially just big washers?

[350matt]

250 QUID???? Blimey are you sure they're original Granada cosworth? I paid 32 quid for my ebay pair.....

For reference all they are is a single piston sliding caliper like the originals with a slightly bigger pad but their mounting brackets are already spaced out to provide room for the bigger disc.

If you were to re-use the existing calipers you'd need to make up a bracket out of steel or aircraft grade aluminium to move the caliper out radially, I'd recommend reading Pete Humphries account on how to do this mod on the Griffith pages

Matt

[griffter]

barreti said:

are they essentially just big washers?

As Matt says, you'd need to space the caliper out radially, not along the disc axis. Your extra braking then comes courtesy of greater leverage - the pads clamp the disc further from the axis of rotation. Problem is, if the pads are no bigger (or negligibly bigger) I can't see how this will improve resistance to fade / repeated applications. In theory it should just reduce required pedal effort. By the time you've told your insurance company, it might have been a better bet to get a properly engineered off the shelf kit. I'm not knocking scrapyard DIYers - that's precisely the kind of engineering I love - but a radially-spaced single pot sliding caliper won't give you the same advantages as a multi-piston conversion (won't give you the same overdraft either...).

[spend]

griffter said:

Your extra braking then comes courtesy of greater leverage - the pads clamp the disc further from the axis of rotation. Problem is, if the pads are no bigger (or negligibly bigger) I can't see how this will improve resistance to fade / repeated applications.

You are using a greater area of disk ~ minimal but not to be discounted in heat dissipation.
Having said that I'm firmly in the TVR AP 4pot route. Most folks are v happy & like the 16" wheels (and tyres...). It is important to plan what you are doing 'in the greter scheme' rather than just odd components in isolation - even then the 'oh wish I'd thought of that then' will get you

Dave