10.87" Disc brake rotors

Pete · Post by **Pete** » Mon Oct 12, 09 6:49 pm

Hi there,

I seem to remember in the dim and distant past there was a debate about the "one piece" later style rotor and the original "two piece" rotor - I have certainly had this discussion with Gavin.

I want to do a cheap front brake conversion from drum to disc.

I have every part, with the exception of decent rotors.

How do I find out which "type" of rotor is compatible with my set up? Is it down to the spindle/knuckle part numbers?

I think the calipers are inter-changeable, so I am not sure just what to order.

I don't know what year car the spindles came off.

I did buy a set of new 10.87" rotors recently, but they did not fit as they "sat in" too far on the rear bearing and rubbed on the spindle.

I was not sure if this was due to poor manufacturing tolerances (the hub was too "deep" between the inner and outer wheel bearing seats) or the reasons stated above.

Any guidance is most gratefully appreciated.

Thanks

Pete

PS - I am also after some Caliper adapter brackets to work with an 11.75" rotor on a "B/E" body spindle if anyone has a pair hanging around - yeah, right......

Blue · Post by **Blue** » Mon Oct 12, 09 6:57 pm

I ain't read through it, but you might find what you need to know here...

http://www.moparaction.com/Tech/archive/disc-main.html

latil · Post by **latil** » Mon Oct 12, 09 7:15 pm

Is there any possibility that Blues very informative link can be stickied please. Thanks for posting that Blue.

Pete · Post by **Pete** » Mon Oct 12, 09 7:27 pm

Thanks Blue, I have been through that a couple of times without spotting the key aspects, it seems a bit generic.

However, I will check again.

Pete · Post by **Pete** » Mon Oct 12, 09 7:34 pm

Well the info WAS there:

Knuckle Part #'s 340628 and 340269 work with uni-cast rotors. These are sourced from an 73-74 E- body, disc- equipped ‘73-76 A- body.

So I will check the part numbers of the knuckles, but what Rotors can I get if the part numbers do not match the above ???

J Clark · Post by **J Clark** » Mon Oct 12, 09 8:01 pm

I very successfully based my upgrade from 10.87" to 11.75" discs on that article!

My old 10.87's were 2 piece and warped to hell!

Unicast rotors are a must. Now got the single piece 11.75's plus a booster and it stops on a dime!!!

Edit: All the information should be in the article, Neil Willett got me my discs. Be aware of the small and large inner bearing type spindles.

Pete · Post by **Pete** » Mon Oct 12, 09 8:10 pm

Thanks Julian

, where did you get the caliper adapter brackets to cope with the larger diameter rotors?

Thanks.

I actually have "almost" enough for 2 upgrades -

1 x 10.87 system - but I need 2 rotors (see above), plus

1 x 11.75" system, but need the larger caliper adapters to ensure the calipers clear the rotors.

So.. I really need both solutions.

Thanks as ever,

Pete

Blue · Post by **Blue** » Mon Oct 12, 09 8:19 pm

Andy Finkbeiner produces various caliper adaptors, info here...

http://www.arengineering.com/caliper_me ... rmenu.html

Pete · Post by **Pete** » Mon Oct 12, 09 8:26 pm

Yes, I have come across Andyf before when looking for other things suspension related. He was very helpful and know his stuff - in fact he was the only person that got his facts straight.

Unfortunately, it does not get me out of this predicament....

J Clark · Post by **J Clark** » Mon Oct 12, 09 8:30 pm

Pete wrote:Thanks Jim, where did you get the caliper adapter brackets to cope with the larger diameter rotors?

Thanks.

I actually have "almost" enough for 2 upgrades -

1 x 10.87 system - but I need 2 rotors (see above), plus

1 x 11.75" system, but need the larger caliper adapters to ensure the calipers clear the rotors.

So.. I really need both solutions.

Thanks as ever,

Pete

I used ebayMotors to get the adapters and spindles, used FBO/Neil to ship back to the UK. There are guys in the states who go out to junk yards and strip these 'desirable' parts off old mopes and then flog them on the bay!

I highly recommend you go for the 'Big Disc' setup. After ebagging my first 'big' adapters I got pipped on a second set that came up, so you have to be quick on the mouse button!

I have the earleir 'pin' type calipers so had the added difficulty of sourcing adapters to suit. The sliding type (no pins) seem more poular and are being re-popped (I think) My Pin type calipers came from Neil Willett (had them in stock at the time).

P.S. its Julian

Pete · Post by **Pete** » Mon Oct 12, 09 8:34 pm

Sorry

Julian, and thanks for the info.

Its never as straightforward as just buying the parts, is it?

J Clark · Post by **J Clark** » Mon Oct 12, 09 8:43 pm

To be honest it was a bit of a mission and I had to be very patient waiting for all the parts to arrive.

Piccys below!

DaveBishop · Post by **DaveBishop** » Mon Oct 12, 09 8:44 pm

Pete don't you remember how hard it is to find those 1973-76 A body knuckles

Pete · Post by **Pete** » Mon Oct 12, 09 8:50 pm

I know Dave, that's why I am not going that route - I have some "B/E" knuckles already but either need caliper adapters, or new 10.87 rotors to make up a set...........

J Clark · Post by **J Clark** » Mon Oct 12, 09 8:57 pm

Pete, if you don't buy them, I blooming well will

Pin Type!!!!!!!!!!

http://cgi.ebay.com/ebaymotors/Mopar-Di ... 3ca648ea65

and here's the slider type!!!!!!!!!!!

http://cgi.ebay.com/ebaymotors/Mopar-Di ... 3ca662a0bb

Are you still reading this!!!!!!!!!!!

Edit: in my opinion, the buy it now on both these auctions is a bargain, I only paid slightly less for mine 2 years ago!!!!!!!!!!