brake rotor sizes??

[randymx5]

how many different rotor sizes are there? and inturn how many different calipar sizes are there (you would think there would be the same..

NA1.6 rotor diameter 235mm
NB1.8 rotor diameter 255mm
1.8 titanniuma and SP turbo 270mm

calipars?? NB1.8 and SP turbo compatibale????



thinking of a 'cheap' brake upgrade..LOL

[hot rod]

how many different rotor sizes are there? and inturn how many different calipar sizes are there (you would think there would be the same..

NA1.6 rotor diameter 235mm
NB1.8 rotor diameter 255mm
1.8 titanniuma and SP turbo 270mm

calipars?? NB1.8 and SP turbo compatibale????



thinking of a 'cheap' brake upgrade..LOL

I'm looking at upgrading my NA brakes aswell. they're possibly some of the worst brakes I've ever experienced lol...

I already have 15-inch wheels so the SP 270mm discs should fit but is this a conmon conversion? I want to change the discs and calipers.
DBA also sell the SP brakes in the 4000 1-piece series.

[Boyracer]

All the brakes bolt straight on to a NA model....you will have to modify backing plates and you need to use the NB8B hoses.

All the NB8B brakes are the same size including the ones on the SP.

[CT]

how many different rotor sizes are there? and inturn how many different calipar sizes are there (you would think there would be the same..

NA1.6 rotor diameter 235mm
NB1.8 rotor diameter 255mm
1.8 titanniuma and SP turbo 270mm

calipars?? NB1.8 and SP turbo compatibale????



thinking of a 'cheap' brake upgrade..LOL

I'm looking at upgrading my NA brakes aswell. they're possibly some of the worst brakes I've ever experienced lol...

I already have 15-inch wheels so the SP 270mm discs should fit but is this a conmon conversion? I want to change the discs and calipers.
DBA also sell the SP brakes in the 4000 1-piece series.

You may want to check the master cylinder and prop valves too. They are different between the NA without ABS and the NB with ABS. Prop valves are not used on the NB8B and SP/SE because of electronic EDB so you may also need to add brake proportioning.

The NA 1.8 brakes are the simplest upgrade because it bolts on without requiring any hydraulic changes. You might be better off rebuilding your current calipers (I'd do it to 2nd hand ones anyway), upgrading lines to stainless, using a good fluid (Motul RBF600 for eg) and using a higher spec pad. You will be amazed at how good stocky brakes can be.

[irwin83r]

im about to go from nb8a brakes to the sp and alike brakes.

can u explain what you said CT again about the prop valves.

and electronic EDB.

will i need more than the calipers, rotors, lines, extenions??

[CT]

My point is not one of actually having done it but rather one of, just check this won't be an issue. In the NB8B, SP and SE, the front to rear proportioning of the brakes are handled by the ECU. They call this electronic distribution of brakeforce (EDB) or similar. In earlier model cars, this was done by the hydraulic proportioning valve that sits adjacent to the master cylinder in the engine bay. My point is that by changing the brakes hardware, you are altering the front to rear balance. If it's in your ECU, it should be able to deal with it. If it's hydraulic, it might be changed enough to worsen your braking - I don't know.

Check out this pic I have borrowed from safetymans beautiful beast.
http://img424.imageshack.us/my.php?image=enginepic28ih.jpg

The silver thing with lines going into it on the right of the master cylinder, is a hydraulic prop valve. So there you go, it's hydraulic. So, for a road legal car you can fit an adjustable one in the engine bay and have it secured so it can't more. For a race car, it must be within fingers reach so you can alter it based on conditions, ie in the wet give more to the rear. BUT, if the piston size of the calipers is unchanged, you will only slightly change the bias so you might be able to correct it with different spec pads front vs rear. If the piston size is different, then you might need a prop valve. I use a wilwood one in the race car.

http://www.wilwood.com/Products/006-MasterCylinders/001-PV/index.asp

If the master cylinder sizes are different things could also go awry. I think NB8B is 15/16 - it's on the top of the MC under the reservior so check yours and see what you've got. Hopefully the same but it could be 7/8ths. Can't remember.

STOP PRESS: ABS and EDB appear to be controlled by a seperate ABS module in the NB8B and not the main ECU. I need a wiring diagram to confirm but so far haven't found one. Off to the big forum...

[fd3s]

wouldnt you need a mount bracket for the brake caliper if you put larger discs on the na - i would presumed so

[Matty]

CT, the prop valve is different between NA6, NA8 and NB8, with the system getting more rear bias each time.

The NB8B/ABS cars use a straight-through fitting that could be replaced by a prop valve, though I have heard of some people adding this fitting to a non-ABS car without problem (ie without rear lockup issues)

I fitted an NB8A prop valve (pn NC10-43-900A) to my car, and noticed a definite improvement. The Wilwood/Tilton would probably be cheaper though...

and yes, when fitting bigger rotors you need new caliper brackets at the minimum. (and pads.)

[Russellb]

CT the ABS has its own computer I know from the Wiring Diagram i have.
As for th ecomputer Bias control I have found no Evidence of one (you can pull the ABS fuse or remove the ABS completely and the Brake Bias dosn't change )
if you would like a wiring Diagram for the 2000 NB Drop me an Email and I'll send you a copy 8MB in total

[CT]

CT the ABS has its own computer I know from the Wiring Diagram i have.
As for th ecomputer Bias control I have found no Evidence of one (you can pull the ABS fuse or remove the ABS completely and the Brake Bias dosn't change )
if you would like a wiring Diagram for the 2000 NB Drop me an Email and I'll send you a copy 8MB in total

Hi Russellb - I'd love that wiring diagram if at all possible to split the file into smaller chunks. But, the ABS ecu does control the EDB which started on 10th month 2000 cars. This is the NB8B and I can assure you the biasing does radically change if you pull the fuse on a car with EDB. NB8A cars from 98 to mid 00 use a seperate prop valve (as seen in the pic from my earlier post) which is why I think you have the earlier NB's wiring diagram. Not sure how the EDB works though, surely it must have a gyro or something???

Matty, yeah funny how the cars have been getting progressively rear biased to a point where it needs EDB to keep it braking in a straight line. I have a wilwood on the race car and it's excellent but from our current tinkering with NB8Bs, there appears to be no reason to disable the EDB and ABS. I suspect however that if the new Porker GT3 has no fancy brake gizmos, then the simple NB8B might be able to survive without them as well.

[Matty]

Matty, yeah funny how the cars have been getting progressively rear biased to a point where it needs EDB to keep it braking in a straight line.)

EBD isn't a bandaid, it's a better system giving optimal braking force under all conditions. That it allows more rear bias under light force is much better for wet/low grip conditions.

Though I have no logical explanation for the excessive front bias in the early cars...

[CT]

Totally agree with you on that one Matty. The next challenge is removing the ABS and keeping the EDB working. I'm fairly sure this is the next challenge re NB brakes. I hope someone cracks it before I have to try

[Boyracer]

Someone on here has a NA6 with NB8B brakes...no change to proportioning valves or master cyl...working fine.


Getting back to the GT3...I outbraked one in my poor old MX5 race car with stock NA8 brakes and Hawk pads....

[RobbieRat]

Someone on here has a NA6 with NB8B brakes...no change to proportioning valves or master cyl...working fine.

Yep that would be me, best mod ive done to the car so far and no issues what so ever

[kula]

you used NB8B front and rear brakes?