Don’t think anyone makes a 203.2pcd bell for the Exige 
closest is the 190.5mm most of us use
I’ve only recently gone to the 190 pcd after about 4 seasons on the 177, which worked perfectly well
I see the point of having the bigger bells as it reduces the rotational mass and unsprung weight, but if nobody makes them you can’t buy them. I use 190.5 pcd both front and rear.
Wonder if I can use bigger calipers and pads to use the rest of the disc surface?
what’s wrong with this picture? a link to a manufacturer, AP Racing, that makes a 315mm disc, 25.4mm wide, with a 203.2mm PCD and the correct 46mm face depth for that caliper…
When the whole surface is not heated up evenly, the disc tends to warp and distort. If it is not distorting, then the disc is way too heavy for the application used. So, either way, you’ve increased the unsprung mass needlessly! Wrong disc for the application.
Not seeing the specifications for that particular disc, but it LOOKS like it was designed for a 52mm to a 54mm pad. Please correct me if I’m wrong there. That is sill too large for the 46mm pad that cailper uses. If the friction surface is not 46mm on the disc, it is the wrong application and not the correct size for that caliper…
As usual with many of your expert posts you miss the points raised. Thank you for your valuable input
Please…enlighten me…I’m always willing to learn. I’d truly love to have a technical discussion here and not a pissing contest…
With facts and data, not just “you got it wrong” or “you misunderstood” or “you missed the point”…
All the brake upgrades use components that are currently available, as I believe only 177 and 190 pcd bells are available to fit our cars that clearly limits the rotors that can be used. Also there are not many caliper options for our cars again this limits what you can use. With a greater budget to have items made or modified to allow for other options I’m sure it is possible to do more. But then I suspect if you increase the caliper size the master cylinder would be too small, then I would need to replace the pedal box, then the ABS needs to go, this turns a cheap upgrade into a really expensive one for what is probably little gain.
If you can source the correct bells to run the 202 pcd rotors then i suspect there might be a line of people to buy them, they just don’t exist currently to my knowledge.
Ade has hit the nail on the head!! I would happily produce larger bells and additional disc rota’s but the cost for upgrades would increase.(significantly)
As with many modification there are compromises to be made one being cost. In an ideal world you would all have million pound budgets to modify your cars, hopefully spending with me!!! The Alcon 315 discs came about as I had some 190.5 floating bells and wanted a larger disc that would do the job hence these discs. In the past the popular mod was an AP disc 315x25.4 x 177.8pcd, so these are a big improvement over that mod with the added advantage that they will bolt directly to the bells supplied by Lotus on cars fitted with 2 piece 308 discs.
I have worn out two sets of PF pads with 100% heavy track use on these discs and they are still all good so the theory that there will be problems with heat transfer/soak is great, but all the same a theory, in practice they work and work well. The key wording to remember with ALL upgrades regardless of what it modified will be COMPROMISE unless you have unlimited budgets. Im sure Graham and Will, have found the same results along with all the others with these discs fitted
See you all at Anglesey…
Simple really the issue is compromise, cost benefit ratio, we don’t all have a massive budget to waste on our cars. as for pissing contest? what???
315 x 177 4pots front, 308 x 177 2 pots back. Revelation. Bloody brilliant. I can’t imagine the 315 x 190 being better at stopping me, just less weight. But hey, if I was that fussed I wouldn’t put the 100Kg bloke in the car.
OK…supply and demand… If enough people demanded the correct parts, there would be a supply of them. We are all here to learn something or share something… I’m just educating people so they could make better decisions. The cost of making a 190mm bell versus a 203mm, I bet is negligible. Start demanding the correct parts people…
And Dave, if you started offering a 315mm disc with a 203mm bell, I bet you couldn’t give away the other ones.
That is also true!
these are mine: