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GSM Performance Customer Car Colouring Book Edition 1
Smart Fortwo 450 300mm 4pot Brake Kit: Wheel Bolts, Replacement Discs And Pads, And Brake Hose Length Explained
A customer asked why the Smart Fortwo 450 300mm 4pot conversion kit comes with six wheel bolts, whether they're longer, and where to get replacement discs, pads and the brake hose length. The kit listing gives six chromed wheel bolts and prints no length for them. Discs and pads each have their own listings. The hose length isn't published, so send us a few details and we'll confirm it.
- Prices read from the live BigBrakes4U site, inc VAT
- Details taken from the kit, disc and pad listings
- No bolt or hose length is printed, so we confirm those with you
Six bolts for the kit, discs and pads sold separately, hose length on request
£1,510.67inc VAT
Read from the Smart Fortwo 450 300mm 4pot Conversion Kit listing and its replacement part listings.
- The kit is priced for both front hubs and lists 6 x chromed wheel bolts. There's no length given for them, so we can't say they're longer.
- Replacement 300mm discs are Hi Spec, 20mm thick, straight vein, spot grooved, with 8 bolt fixings, sold one rotor at a time.
- Replacement pads are sold as a set for 2 calipers, which is one full conversion.
- The kit comes with braided hoses made by the kit maker. No length is printed, so send us your details and we'll confirm it.
Why the kit lists six wheel bolts, and whether they are longer
The kit is priced for one complete conversion, both front hubs, and the contents list ends with 6 x Chromed Wheel Bolts. That’s all the listing says about them. There’s no length or thread size, and nothing to say they’re longer than the bolts already on the car.
Garreth’s advice is to put the supplied bolts next to the ones you take off and compare length and thread before anything goes back on. Send us those measurements with your wheel details and Cameron will confirm what you’ve got in front of you.
The listing does say the kit is designed to sit inside Brabus 16 inch Smart wheels or larger without spacers or washers, so check your wheels against that too.
What the 300mm 4pot kit contains
This is the Smarts4you Racing 300mm 4pot kit for the Smart Fortwo 450. The calipers are CNC machined from billet bar with hard anodised aluminium pistons. Each bracket is machined from a single piece of aluminium, sized so the calipers fit without spacers or washers.
The listing explains why it’s four pistons. The maker trialled 6 pot calipers on small cars and got far too much pedal travel and a spongy feel, so these are 4 pot to suit the size, weight and master cylinder bore of the car. The price covers one complete kit for both front hubs.
- From £1,510.67 inc VAT
- 2 x 4pot radial calipers, 2 x 300mm rotors, 2 x bells, 2 x brackets
- 1 x bracket hardware pack, 1 x DOT 5.1 brake fluid
- 1 x EBC Standard Road Pads, upgradeable
- 2 x braided hoses included, 6 x chromed wheel bolts
Product cards show prices excluding VAT. Prices in the text include VAT.
The disc design and replacement 300mm discs
The rotors in the kit are two piece, a 300mm disc bolted to an aluminium bell. The kit listing describes them as drilled and grooved, to help cooling, release gas between pad and caliper and keep the pads deglazed. Because the disc and bell are separate parts, a worn disc is replaced on its own and the bell stays on the car.
The replacement listing calls its disc spot grooved, so both listings agree on the grooves. If you’re not sure which kit you run, the listing asks for a photo of the caliper and disc so Cameron can identify it before you order.
The Hi Spec 300mm Straight Vein Spot Grooved Rotor is the replacement we list for the Smarts4you 300mm kits. The listing says the grooves improve heat dissipation, reduce gas build up on the disc and pad surfaces and help with continuous pad deglazing. In wet weather they stop a film of water building up between disc and pad.
The price is for one rotor that bolts to your existing bell, so a pair for the front axle means two.
- From £185.14 inc VAT, per rotor
- Diameter 300mm, thickness 20mm
- Straight vein, spot grooved
- 8 bolt fixings, bolts to your existing bell
Replacement pads for the 300mm 4pot calipers
The kit ships with EBC Standard Road Pads and the listing marks them as upgradeable. Each replacement listing is for a set to fit 2 calipers, which is one full conversion, and each is written for the Smarts4you 300mm 4pot calipers. We list six compounds, and the table has all six with what each listing says.
Garreth says choose the pad by how the car is driven: road only, road and the odd track day, or track only.
| Pad | What the listing says |
|---|---|
| EBC fast road | Named as the fast road pad. The listing adds no compound detail. |
| EBC Redstuff | Kevlar fibre based with ceramic particles, listed as the lowest dust pad for faster street driving. Bed-in can take up to 1000 miles. |
| EBC Yellow | Aramid fibre based, strong from cold, for street and track. The listing says it is not a low dust pad. |
| Ferodo DS2500 | For track days, with a friction coefficient of 0.50 at any temperature and minimal bedding in. |
| Ferodo DS3000 | Ferodo's premium racing compound, friction coefficient 0.62, bedding in about 50% quicker than other materials. |
| Mintex 1166 | Developed for circuit racing, with a stable coefficient of friction up to 800 C. |
Each listing is for a set of pads to fit 2 calipers. The EBC fast road pads and the Ferodo DS3000 pads are listed separately.
Brake hose length
Two braided hoses come with the kit. According to the listing the maker builds them from stainless steel braided hose swaged onto stainless steel fittings, with a clear or coloured protective coating. It doesn’t print a length, and we found no separate hose listing for the 450 kit, so we won’t quote a figure.
If a hose needs replacing, tell us the car, which kit you run and the coating colour, and send a photo of the hose if you can. Cameron will come back to you with what you need.
Common questions
Are the six wheel bolts longer than the standard ones?
The listing does not say. It lists 6 x Chromed Wheel Bolts with no length or thread size, so compare them with the bolts from your car and send us the measurements. It does say the kit fits inside Brabus 16 inch Smart wheels or larger.
Why does the kit list six bolts?
The price is for a complete kit for both front hubs and the contents list gives six chromed wheel bolts with it, though the listing does not explain the number.
Which replacement disc do I order?
The Hi Spec 300mm Straight Vein Spot Grooved Rotor is 20mm thick with 8 bolt fixings and is sold one at a time, so a front pair is two. If you are unsure which kit you run, send a photo of the caliper and disc.
Which replacement pads should I choose?
Garreth says match the pad to how the car is driven. The EBC Redstuff is listed as low dust for faster street driving, and the Ferodo DS2500 is listed for track days. The table above covers the other four compounds.
How many pads come in a replacement set?
A set fits 2 calipers, which is one full conversion for the front axle.
What length are the brake hoses?
The listing says braided hoses are included and made by the maker and prints no length, so send us your details and we will confirm before you order a replacement.
Will the kit clear my wheels?
The listing says it fits inside Brabus 16 inch Smart wheels or larger without spacers or washers. For any other wheel, tell us what you run and we’ll confirm clearance before you order.
Why 4 pot calipers and not 6 pot?
The maker’s listing says the 6 pot calipers they trialled gave far too much pedal travel and a spongy feel on small cars, so the calipers are sized to suit the car’s weight and master cylinder bore.
What we would buy
Garreth
Garreth's top tip
For a Smart that sees fast road use I would fit the EBC Redstuff pads when the first set wears. They are listed as low dust, and that suits a car you drive every day. They bed in slowly, up to 1000 miles by the listing, so allow for that.
If the car goes on track, the Ferodo DS2500 is the one I would pick, because the listing is written for track days.
Cameron
Cameron's fitting view
I like the single piece brackets, because the calipers go on without spacers or washers. Before the wheel goes back on, lay the new bolts next to the originals and compare length and thread.
Discs are straightforward. You buy one rotor at a time and bolt it to the existing bell, which stays on the car. Send me a photo of the caliper and disc and I'll confirm the match.
Not sure which disc, pad or hose you need?
Tell us the car, the kit and your wheels. Cally, our digital receptionist, takes your details, and Cameron comes back to you with the right parts before you order.
