Front brake upgrade

pearsy85 · Post by **pearsy85** » Sun Mar 15, 2020 12:58 pm

All websites list 5th gen and ATR as 70mm bore not 64.1?
I would love to upgrade to ATR brakes as you have more options for discs, but I do t want to risk buying them and they are the wrong size.

Post by **RattyMcClelland** » Sun Mar 15, 2020 2:30 pm

Where are you looking?

Google "prelude centre bore" and everything is 64.1 with 5th gen being the first result.
I run 64.1 to 73mm spigot rings and spacers for my wheels. Even the Accord is 64.1. Both the 6th gen and 7th gen accord. Got them all on my drive and inlaws drive next door and fitted all wheels on all cars vice versa.

Scott560 · Post by **Scott560** » Sun Mar 15, 2020 3:30 pm

Even if the discs centre bore is larger than the wheel/hub, i don't think it makes much difference, since the disc is centered via the screws and held in place by the 5 studs...

the 300mm atr discs , they fit with the ATR carriers and calipers, and good braking happens. I was doing 10+ lap stints at bedford without issue. They do fit under the standard 5th gen 16 inch wheels, but only just, slim wheel weights needed lol.

I've had no issue with the mtec drilled and groved discs, i check them regularly for cracking just incase. they are barely even worn aswell despite having done a few track days and about 2 years of day to day driving.

pearsy85 · Post by **pearsy85** » Sun Mar 15, 2020 4:36 pm

I looked on all the big manufacturers of discs for centre bore sizes, EBC, Tarox, Brembo etc, all say 70mm for 5th Gen and accord, apart from the 2.0 5th gen that was 64.1, so I dunno.

The centre bore is important for the disc to be centralised, you can't rely on the bolt to centre at all.

I think I'm gonna try some decent pads first, as the Black Diamond Predator ones don't bite well under massive load when hot, so that won't help, gonna order some yellow stuff I think, if worse comes to worse, I might get a bank of sorts but they start at around £800-£900

Scott560 · Post by **Scott560** » Sun Mar 15, 2020 7:28 pm

I can well imagine that the discs are 70mm central bore, and the car hub is 64.1 , but it makes not a jot of difference to the brake disc, it centres with the screws and on the studs pretty firmly. Once the wheel is bolted on (which does rest on the centre bore and does need to match), the discs isn't going anywhere - if they did i think i would have found out by now (both cars had ATR discs for a long time, wheels been on an off many times also).

If your re-drilling the 5 studs to 4 stud pattern, then yeah you might have to be a bit accurate with the drilling for sure.

Not that i was worried, but the OE fitment for 5th gen 2.2 282mm discs is 70mm centre bore, so i'm not worried, and i dont think anyone else would be (otherwise, we would have heard by now, or my brakes would have fallen off lol).

5th gen 70mm bore:
https://brakeparts.co.uk/shop/Honda/Pre ... ms/BDS5635

every prelude ever 4th or 5th gen wheel is 64.1
https://www.wheel-size.com/

I guess that having discs too close to the centre hub causes removal issues (rust etc), when there is no need for it on an engineering level (but there is for wheels for sure).

ATR84 · Post by **ATR84** » Sun Mar 15, 2020 8:57 pm

To those of you that have upgraded to ATR brakes, is it worth it?

Post by **RattyMcClelland** » Sun Mar 15, 2020 9:19 pm

Yes worth it. Takes heat better and grabs better.

However....if you are used to modern brakes they dont bite as hard but stop all the same. I have brembo 4 pots with 340mm discs in my vw T6 and the initial bite will give you whiplash. Preludes are very progressive even with atr brakes.

Scott560 · Post by **Scott560** » Sun Mar 15, 2020 10:25 pm

Deffo worth it if you are doing track days, otherwise not worth it at all.

ATR has a larger master cylinder, so they are very progressive on the prelude with its smaller master cylinder. Not much bite at all as mentioned.

Cannot overheat my 300mm setup. I'm going to give them a refresh in the coming weeks (new seals, hone the bores etc), to try and get them feeling a little better, as I would like a slightly better pedal feel.

As said - was doing some serious stints at bedford, and not once did the brakes give me a hint of trouble, and that was 175miles of track time.

Cant comment on other setups - but the larger discs seemed to be the key to me, the ATR ones are much wider also, which gives much more cooling potentially (the vented sections are bigger naturally).

If you start adding it up, its gets pricey to do. any ATR calipers you pick up are going to be old, so they will need refurbing and associated hardware also.

still, best thing for a track car, not necessary on a prelude. Anyone who is getting hot brakes on the road needs to have a word with themselves.

ATR84 · Post by **ATR84** » Mon Mar 16, 2020 7:43 am

@Scott560 I have never tracked mine, and if I did I would probably take it quite easy. I think I am just looking at potential upgrades on the Type S out of boredom/curiosity as there is nothing really left to do on the car.

Scott560 · Post by **Scott560** » Mon Mar 16, 2020 10:08 am

ATR84 wrote: ↑
Mon Mar 16, 2020 7:43 am
@Scott560 I have never tracked mine, and if I did I would probably take it quite easy. I think I am just looking at potential upgrades on the Type S out of boredom/curiosity as there is nothing really left to do on the car.

Leave it original , freshen up what is old, make it pretty and be happy in the knowledge it's as designed. Unless your brakes are overheating, you don't need to pimp them up. It was a fair effort/cost to get calipers and carriers, clean them up, new seals and pistons, paint them, fit it all with new hardware discs and pads. Unless your tracking it, its not worth the effort.