1975 Manta Brake ?'s

[Mini Stock Manta]

I have a 1974 Manta with 1975 Rotors and calipers on my sons mini stock car. I need to find vented rotors and a good racing brake pad for the larger 1975 front brakes. Do any of you know where to turn?
We have seven Opels, two are race cars and the metallic pads and vented rotors are a must find.
Than you,
Mini Stock Manta

[BQS4]

I don't think there was a "stock" vented rotor for the 75, but, ATE has a kit that will allow you to widen the stock 75 caliper and use the internal vented rotors off a Rekord D or E, which is a 246mm disc, all of this is bolt on. Dave McCollam has this set up on his Manta Rallye, he just doesn't have the metallic pads on it

[Paul]

The 75 solid rotors are the same as a BMW 320 of a particular year, someone will know... Subsequently there are vented rotors of the same OD to fit that model BMW of other years, again someone will chime in... It requires vented rotors and the calipers at a minimum... I believe Otto has published a nice illustrations of how to accomplish.... Just wait you'll get the answer you need... its arround here somewhere

[Paul]

A good pad? I'm using EBC Green stuff pads and love em. Hawk makes some too. You'll need to check out the Sports Car suppliers, like the ones that support SCCA Road Racing.

Pegasus Auto Racing Supplies - Home Page
www.racerpartswholesale.com

I've purchasd stuff from both and are good online companies to deal with.

[RallyBob]

Hawk Blue pads and Porterfield R-4 racing pads both work well for short track use, I've used them both before. They take a little heat to get them working, but once they're warm...they stop.

A few options are:

*1977 BMW 320i rotor, turn the OD down to the same size as the stock 1975 Opel rotor (must do this), use the BMW hubs from the same year (same bearings), and use the BMW calipers from the same year...they bolt right up. The calipers are identical to the 1975 Opel calipers, except they are already spaced from the factory for the vented rotors.

*Stock European Opel Omega/Vauxhaul Carlton 'small' brakes as fitted to the 4-cylinder cars, which are vented rotors that are the same diameter as the 1975 Manta rotors, and they fit to the stock Opel hubs just like OEM (because they are!). This setup uses a sliding single piston caliper however, which is not as stiff as the 2-piston calipers. I have also retrofitted this setup with a Wilwood 4-piston (1.38") caliper with good results.

*There are other options, but the tough part of course is fitting them under 13" wheels. I recently made a setup for my road racing Manta with 10.5" x 1.150" thick vented racing rotors and 4-piston Superlite Wilwoods. Fits inside 13" wheels! But not cheap.

HTH,
Bob

[Mini Stock Manta]

Thank you for the information, my son will no doubt be safer with the upgrade. The right front is terrible for overheating. I have been reading your posts and replies and learning a great deal from you all. We are glad to have found this site. I have a lot of Opel parts and cars if someone is in need. Thanks again for the great information.


Mini Stock Manta

[dallasmanta]

Bob,

Please confirm that you are suggesting the use of the bmw hub in place of the 75 opel hub for the 1977 year. My experience has been that the 77 Bmw hub does not fit the opel spindle as the 75 opel spindle is thinner in dia. I set up the BMW hub by using bearing spacers pressed in to the hub to use stock opel bearings. Yes it is true that turning the77 Bmw rotor to opel size works with the expanded 77 bmw caliper and is an exact bolt up. Personally I did not like how my 75 felt with the setup an called Gill at otgs and got the opel vented rotors from him to bolt up to the opel hub. This combo worked better. Ron.

[RallyBob]

Originally Posted by dallasmanta Bob, Please confirm that you are suggesting the use of the bmw hub in place of the 75 opel hub for the 1977 year. My experience has been that the 77 Bmw hub does not fit the opel spindle as the 75 opel spindle is thinner in dia. I set up the BMW hub by using bearing spacers pressed in to the hub to use stock opel bearings. Yes it is true that turning the77 Bmw rotor to opel size works with the expanded 77 bmw caliper and is an exact bolt up. Personally I did not like how my 75 felt with the setup an called Gill at otgs and got the opel vented rotors from him to bolt up to the opel hub. This combo worked better. Ron.

My setup was originally from Carl Schneider (the 'C' of C & R Small Cars). He told me the hub was the BMW hub...it doesn't look like the Opel hub at all, but it fits directly to my spindles. I've used the same setup on three cars. But I can check them to be sure.

Bob