|
|
| Line 57: |
Line 57: |
| | | | |
| | ===Disc brake upgrade=== | | ===Disc brake upgrade=== |
| − | Personally, I I like the Scarebird setup. Basically they supply the brackets for the calipers and the correct spacers for the spindles/rotors, and a tech list of parts to finish the job.
| + | Aftermarket parts options: |
| − | For clarification purposes only, here is an example. On a 58 Pontiac they supply the brackets and spacers - From any source, new or used, you need a pair of 77 Bonneville 12 inch hubs/rotors, a pair of 88-91 GM truck calipers, and 2 choices of flex hoses depending on whether you want them 12 or 15 inches long. | + | *[http://www.scarebird.com/6928.html Scarebird Classic Brakes] makes a setup for many General Motors makes and models. They supply the brackets for the calipers and the correct spacers for the spindles/rotors, and a tech list of parts to finish the job, for $100-$150, depending on application. For example, for a '58 Pontiac, they supply the brackets and spacers. From any source, new or used, you need a pair of '77 Bonneville 12-inch hubs/rotors, a pair of '88-'91 GM truck calipers, and 2 choices of flex hoses, depending on whether you want them 12 or 15 inches long. |
| − | Note: From CPP (Classic Performance Parts) you can get a tapered bearing conversion kit.
| + | |
| | | | |
| − | If you are using all new parts, you can have disc brakes cheaper than rebuilding the original drum setup.
| + | *From [http://classicperform.com Classic Performance Parts], you can get a tapered bearing conversion kit. |
| | | | |
| − | Footnotes;
| + | If you are using all new parts, you can have disc brakes cheaper than rebuilding the original drum setup. |
| − | Your original drum setup used ¼ inch brake lines. 3/16 is recommended for disc brakes.
| + | |
| − | Many aftermarket MC’s have Metric fittings. You may find yourself putting different fittings on each end of your new lines to convert from Metric to Standard. There is a direct metric match to the American 3/16 line size, so that is not a problem.
| + | |
| − | Master cylinder size is important, but slightly flexible. I like the corvette style MC, with ports out each side. Makes installation easier, and they are pretty cheap. The 1 inch bore will do the job, but expect the pedal travel to be a bit long. On the other hand, a 1 ¼ or larger MC will move the fluid faster (shorter stroke) but the small 7 inch booster will not be up to the job. Your original MC may push the discs fine as far as volume goes, but pressure could be another matter.
| + | |
| − | Virtually all cars will need an adjustable proportioning valve. (Any change from the original setup – front or rear weight change, tire sizes, line sizes, rake or tail drag, disc conversion, etc. etc. has the potential to throw your brake system out of balance.)
| + | |
| − | Most disc conversions will require at least 15 inch wheels, check it out before you order.
| + | |
| | | | |
| − | *I have no personal connection, or interest in, Scarebird Classic Brakes, in fact I didn’t even use them on my car, but that’s a whole different story we’ll get into in the next chapter. I recommend them because others have been very impressed with the product and they make a setup for Buick, Olds, Pontiac, Corvair, Dodge, Plymouth, Cadillac, Ford, Mustang, MGB, you name it. Plus I like the idea of knowing exactly what over the counter, inexpensive, parts will be needed later when you do a brake job. | + | ===Notes=== |
| | + | *Your original drum setup used ¼-inch brake lines. 3/16" is recommended for disc brakes. |
| | + | *Many aftermarket master cylinders have metric fittings. You may find yourself putting different fittings on each end of your new lines to convert from metric to Standard. There is a direct metric match to the American 3/16" line size, so that is not a problem. |
| | + | *Master cylinder size is important, but slightly flexible. One option is the Corvette-style master cylinder, with ports out each side. Makes installation easier, and they're fairly cheap. |
| | + | *The 1-inch bore will do the job, but expect the pedal travel to be a bit long. On the other hand, a 1 ¼" or larger master cylinder will move the fluid faster (shorter stroke), but the small 7-inch booster will not be up to the job. Your original master cylinder may push the discs fine as far as volume goes, but pressure could be another matter. |
| | + | *Virtually all cars will need an adjustable proportioning valve. (Any change from the original setup – front or rear weight change, tire sizes, line sizes, rake or tail drag, disc conversion, etc., has the potential to throw your brake system out of balance). |
| | + | *Most disc conversions will require at least 15 inch wheels; check it out before you order. |
| | | | |
| − | Update. I ended up with a corvette 1 inch master cylinder and a 7 in single stage booster.
| + | The project in this tutorial used a Corvette 1-inch master cylinder, and a 7-inch single stage booster. This combination turned out to be "close enough". The brakes are a vast improvement over manual drums, but not perfect. Stopping power is great, until about the last 20% of pedal travel, as several test panic stops revealed. At the very bottom, you just can’t push hard enough to lock them up. The system probably needs a 9 or 10 inch booster to be perfect. There simply isn't enough power in a 7in booster to lock up a set of 215x75 15s on a 3500 pound car, on dry pavement. |
| − | My opinion is: close enough. The brakes are a vast improvement over manual drums, but not perfect. Stopping power is great to about the last 20% of pedal travel. I made several panic stops to test the system. At the very bottom, you just can’t push hard enough to lock them up. Simply put, the system needs a 9 or 10 inch booster to be perfect. The tech man I spoke with at CPP felt the 7 inch dual diaphragm would have been better, but not much. There simply isn’t enough power in a 7in booster to lock up a set of 215x75 15s on a 3500 pound car, on dry pavement. The reason I say close enough; this would only be an issue in a total panic situation, to a full stop, on dry pavement. In that situation, do you want them to lock up?
| + | |
| | | | |
| | ==Front Suspension== | | ==Front Suspension== |
Your Privacy Choices