300mm Front Brake Conversion(with pics!)

300mm Front Brake Conversion(with pics!)

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N7GTX

Original Poster:

7,823 posts

142 months

Friday 28th August 2015
quotequote all
After reading some old posts on here about the 300mm front brake conversion, decided it might be a good idea as the insurance company's next question after telling them the car had a turbo was, "Have the brakes been modified then?"

The original discs were 240mm...


I bought reconditioned calipers from Euro Car Parts. I chose Pagid ones as I've always found their stuff good quality. Their part numbers are 133590311 and 133590324 for left and right. Simply enter them into the search box on the home page:
http://www.eurocarparts.com/ecp
They cost £62 each plus vat and a surcharge of £25 per caliper so if you do not have old ones to return you will pay this. Then the total price would be £208.

To keep costs down, I sourced carriers from a scrapyard. They were from a Ford Mondeo Mk3 and are all the same size. You cannot use the Mondeo discs as they are 5 stud. If you want to buy the carriers separately they are often on eBay and the Bosch part number is 0204Y01125. They are not handed so just order 2 of them.


The discs are from a Ford Focus ST170 and are 300mm. The Euro Car Parts number is 104590548 and cost £25.21 each inc vat. They are vented, 24mm wide, 4 stud and the center hole is the same size as the hub.


The brake pads are again Pagid, for a Ford Mondeo Mk3, from Euro Car Parts, part number 101590298 costing £26.58 inc vat.

After removing the old calipers and discs there are 2 adjustments that need to be made.
1. The mounting holes on the hub - 10 mm - need to be enlarged to take 12 mm diameter bolts. A 12mm drill bit does this very easily.


2. Due to a difference in offset between the discs it is necessary to buy 4 longer mounting bolts and then fit a spacer on each one. You can see the gap between the carrier and the hub in this picture. The gap was 15mm. I used washers to accurately measure the gap.
I got M12mm x 40mm socket head high tensile screws, grade 12.9, from a local supplier, Kays Fasteners, for £2.50. I used the tubes from old suspension bushes I found in the scrapyard that were 12 mm diameter and then cut them to size as they are thick walled and strong.


For clarification these are the actual screws fitted, not the silver plated ones used to set up and measure in the picture above.

|http://thumbsnap.com/Enh7j5aM[/url]

I painted the carriers and calipers with red Hammerite Smooth paint from B&Q for £8.48 giving them all 2 coats.
http://www.diy.com/departments/hammerite-red-gloss...

This is the result:


Once they were all assembled and fitted, the new brakes were bled with 6 pumps of the pedal on each side enough to expel all the air. The wheels were fitted. Mine are the original 15 inch diameter ones so this is all a close fit. The passenger side wheel went on okay with a gap of just 0.5mm.
However, the driver's side was just catching between the rim and the corner of the caliper. By turning the wheel a few turns a mark was left in the newly painted caliper. I then hand filed this until I had the clearance. The calipers are cast so this is an easy fix.


I painted the caliper again and fitted the wheel. This is the result.



If you want more stopping power you can get drilled and grooved discs from companies such as Demon Tweeks and Tarox. The Tarox website lists 3 types and this gives an idea of what is available for standard Chimaera replacements.
http://www.tarox.co.uk/shop/tvr/chimaera/?filterin...

You will need the Ford Focus ST170 300mm ones shown here:
http://www.tarox.co.uk/shop/ford/focus-mk1-98-05/p...

If you are doing track days then you will probably also need uprated brake pads which are very much a personal choice.
For the observant out there, you may have noticed the Mud and Snow tyres on the front of the car. Someone obviously wanted a very cheap set to sell it. I have 4 new ones on order.

I hope this helps anyone considering this upgrade.

P.S. Although there is clearance between the wheel and caliper it is quite tight if on original 15" wheels. If you have 16" or above then no issues at all.
For my own peace of mind I have now fitted 3mm wheel spacers all round at £5.49 a pair.
http://www.ebay.co.uk/itm/3mm-Alloy-Wheel-Spacer-S...

Edited by N7GTX on Friday 28th August 14:45
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Edited by N7GTX on Friday 28th August 15:34


Edited by N7GTX on Friday 28th August 15:39


Edited by N7GTX on Monday 31st August 11:10

anonymous-user

53 months

Friday 28th August 2015
quotequote all
Looks like you're about ready to loose your balance weights?

Hedgehopper

1,537 posts

243 months

Friday 28th August 2015
quotequote all
Thanks for taking the time to send this interesting write-up.

I assume that the new calliper bolts would have to be of a very hi-spec.for this application?

Do these calipers have larger pistons than the normal 887/888 mod?

Edited by Hedgehopper on Friday 28th August 13:25

QBee

20,904 posts

143 months

Friday 28th August 2015
quotequote all
Hedgehopper said:
Thanks for taking the time to send this interesting write-up.

I assume that the new calliper bolts would have to be of a very hi-spec.for this application?
Superb write up clap

And that was my first thought too - those had better be high tensile steel bolts. Standard bolts will shear in time.

BoostedChim

541 posts

224 months

Friday 28th August 2015
quotequote all
It does sound like a bigger and cheap alternative to 888/887 calipers. I would check those bolt are high tensile, £2 sounds a bit cheap for them. Ideally you need 12.9 or 10.9 not the standard 8.8 most bolts are, it'll be stamped on the bolt head. Personally I would put a set of 16" on the front as well, thats a bit too closer for my liking. If you hit a pothole and it buckles the wheel, that gap would lock the wheel up.

N7GTX

Original Poster:

7,823 posts

142 months

Friday 28th August 2015
quotequote all
TVRMs said:
Looks like you're about ready to loose your balance weights?
No, they just get past!

N7GTX

Original Poster:

7,823 posts

142 months

Friday 28th August 2015
quotequote all
Hedgehopper said:
Do these calipers have larger pistons than the normal 887/888 mod?

Edited by Hedgehopper on Friday 28th August 13:25
The piston in each caliper is 57mm diameter if that helps.

Edited by N7GTX on Friday 28th August 15:43

N7GTX

Original Poster:

7,823 posts

142 months

Friday 28th August 2015
quotequote all
BoostedChim said:
It does sound like a bigger and cheap alternative to 888/887 calipers. I would check those bolt are high tensile, £2 sounds a bit cheap for them. Ideally you need 12.9 or 10.9 not the standard 8.8 most bolts are, it'll be stamped on the bolt head. Personally I would put a set of 16" on the front as well, thats a bit too closer for my liking. If you hit a pothole and it buckles the wheel, that gap would lock the wheel up.
Main post now amended!
The plated screws shown in the picture were used for setting up and measuring only as I had them in my van. The ones I have used on the actual fit are M12 x 45mm socket head, high tensile 12.9 screws as you recommend!. They cost £2.50 for 4 to be exact (not £2) and from Kay's Fasteners (now called Kay Fast) in Ossett next to where I live. They do mail order mainly. Very helpful and knowledgeable people.

I was concerned about the clearance but it is just at the corner of the caliper where it meets the smaller diameter part of the wheel. I have now ordered some 5 mm wheel spacers which should give sufficient clearance. As the pads wear down then this will help too.

Edited by N7GTX on Friday 28th August 15:37

carsy

3,018 posts

164 months

Friday 28th August 2015
quotequote all
Excellent write up Iain.

I`m sure your efforts on cobling together another big brake upgrade will benefit many others now that the 887/888`s are becoming very scarce.

Good work. thumbup

Barreti

6,680 posts

236 months

Friday 28th August 2015
quotequote all
Great work Iain.
If you don't mind I'll pinch all the details for the Griffith Alternative Parts List - which is a bit of a misnomer because I love recording stuff like this for posterity.

You're from Ossett? My home town and my mum and two brothers still live on Bankfield Close, Dimple Wells Rd and Headlands respectively.
Where abouts are you?

davelittlewood

306 posts

132 months

Friday 28th August 2015
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You've just set up my next shopping list, thanks for that!



mk1fan

10,507 posts

224 months

Friday 28th August 2015
quotequote all
Mk6 Fiesta ST 150 278mm set up fits too. Uses M10 fixings so no drilling or shaving required. Bit more comfortable behind 15s.

Cokes

475 posts

113 months

Friday 28th August 2015
quotequote all
Amazing write up and a new shopping list for me.

N7GTX

Original Poster:

7,823 posts

142 months

Friday 28th August 2015
quotequote all
Barreti said:
Great work Iain.
If you don't mind I'll pinch all the details for the Griffith Alternative Parts List - which is a bit of a misnomer because I love recording stuff like this for posterity.

You're from Ossett? My home town and my mum and two brothers still live on Bankfield Close, Dimple Wells Rd and Headlands respectively.
Where abouts are you?
Help yourself! I need to look at the rears next. Seen another thread with the current larger vented set up but might do some wandering in my favourite scrpayard. You never know....
I'm in Horbury, opposite the Victoria pub on Westfield Road/Victoria Street junction.

Glad you men like it, its so much better with pictures. Thanx thumbup

Edited by N7GTX on Friday 28th August 23:30

trev4

736 posts

161 months

Tuesday 27th September 2016
quotequote all
mk1fan said:
Mk6 Fiesta ST 150 278mm set up fits too. Uses M10 fixings so no drilling or shaving required. Bit more comfortable behind 15s.
I thinking about trying this do you know what disc's are used.

Thanks

mk1fan

10,507 posts

224 months

Tuesday 27th September 2016
quotequote all
Depends on what item you're happy modifying.

IIRC the factory set up is the same as the S.

That being so, then you can buy the 283mm Cosworth discs that are close to the same height as the 240mm discs. This MAY require a washer between the calliper carrier and the upright but it might not. It will depend on the upright casting tollerances.

There are two options to get the disc to run in the calliper.

One is to file back the leading edges of the calliper castings by a couple of mm. Easily done with a dremel. Some people don't want to do this on the basis that it weakens the calliper. IMHO the amount of material and the area it is removed from it doesn't effect the structural integrity of the calliper.

The other option is to get the discs turned down to 278mm. A simple job for a machine shop.

If you use turned down discs, then you should be able to bolt everything on in one go with just some M10 washers to hand just in case. If you stick with 283mm discs then have your dremel to hand to file the calliper edges.

Alternatively you can use the 278mm discs but you would need a spacer between the upright and the calliper carrier to align the disc and calliper. This is because the 278mm discs are not as high as the 283mm. 45mm IIRC compared to 55mm of the 283mm.
Personally, I would either get the 283mm discs turned down or dremel the edges of the calliper.

Part numbers are in the S forum brake wiki.

I saw a set of callipers on one of the faceache TVR pages recently.

QBee

20,904 posts

143 months

Tuesday 27th September 2016
quotequote all
N7GTX mentions doing the rears next. Did he do them? What did he use?

I found that fitting ventilated grooved 273mm (ie standard sized) Black Diamond disks and decent pads (I used DS2500 Ferodo) gave my rear brakes plenty of stopping power even on track.
They are combined with 324mm fronts with grooved disks (Black Diamond again - Focus RS), 4 pot callipers and Hawk pads.
And yes, I do run 17 inch wheels all round.

N7GTX

Original Poster:

7,823 posts

142 months

Tuesday 27th September 2016
quotequote all
QBee said:
N7GTX mentions doing the rears next. Did he do them? What did he use?

I found that fitting ventilated grooved 273mm (ie standard sized) Black Diamond disks and decent pads (I used DS2500 Ferodo) gave my rear brakes plenty of stopping power even on track.
They are combined with 324mm fronts with grooved disks (Black Diamond again - Focus RS), 4 pot callipers and Hawk pads.
And yes, I do run 17 inch wheels all round.
Not yet QBee. Should really have done them while overhauling the suspension bushes. rolleyes

You lot keep spending my money...frown

S1_RS

782 posts

198 months

Tuesday 27th September 2016
quotequote all
A very similar conversion to what I have on the front of my Puma, although I'm using Focus ST170 calipers as well as the 300 discs. I went for EBC grooved discs and a set of Mintex M1144 pads, very good from cold but when warmed up its a fantastic setup, loads of stopping power with plenty of feel. How much does the TVR weigh, out of interest?

FoxTVR430

452 posts

110 months

Tuesday 27th September 2016
quotequote all
S1_RS said:
A very similar conversion to what I have on the front of my Puma, although I'm using Focus ST170 calipers as well as the 300 discs. I went for EBC grooved discs and a set of Mintex M1144 pads, very good from cold but when warmed up its a fantastic setup, loads of stopping power with plenty of feel. How much does the TVR weigh, out of interest?
A round 1060Kg smile