Disc swap questions

[SSHAKERR]

So I am about to swap my front drums for the 11.75" x 1" disc set up. I have the slider type caliper adapters from a Cordoba. It will not cost me much to buy new calipers, but... I was considering buying the Dynalite caliper bracket from Mancini. That plus a set of forged Dynalite calipers, vented and cross-drilled 11.75" rotors is looking pretty appealing. Here are my questions reguarding the swap~

1. How much weight does the dynalite setup save over stock caliper?

2. I will be installing a new 2 bolt master cylinder on an adapter plate in place of my stock job. Do I need the adjustable push rod if I am stayong away from a power booster?

3. Anyone have anything to say about the willwood dynalite calipers?

~Thanks

[John Kunkel]

If you want looks the Dynalite is hard to beat but it'll never equal the clamping power of the stock Mopar single caliper.

[Madman Stephan]

Yeah, what John said...

If you're running big, see-thru rims and just cruising around, the Dinalites will do.

[SSHAKERR]

My order of importance is:
1. Function.
2. Weight.
3. Looks.

"Combined piston area, not caliper size, is the primary influence on a caliper's clamping power. The piston volume must match the master cylinder bore size and pedal leverage to realize peak performance from the system. Rotor diameter will also impact the system's effectiveness."

Wilwood offers billet Dynalite and Forged billet Dynalites. The forged ones are cheaper. I dont get that? Both varieties are available with 1.38", 1.62", and 1.75" bores and are four piston design. I am not sure which would be wilwoods best combo for my car. And you guys are telling me that I would be better off with an inexpensive rebuilt single piston caliper from Autozone than Wilwoods best Dynalite combo? Thats hard to believe. Now I need to do more research.

[dwc43]

Originally Posted by SSHAKERR

My order of importance is:
1. Function.
2. Weight.
3. Looks.

"Combined piston area, not caliper size, is the primary influence on a caliper's clamping power. The piston volume must match the master cylinder bore size and pedal leverage to realize peak performance from the system. Rotor diameter will also impact the system's effectiveness."

Wilwood offers billet Dynalite and Forged billet Dynalites. The forged ones are cheaper. I dont get that? Both varieties are available with 1.38", 1.62", and 1.75" bores and are four piston design. I am not sure which would be wilwoods best combo for my car. And you guys are telling me that I would be better off with an inexpensive rebuilt single piston caliper from Autozone than Wilwoods best Dynalite combo? Thats hard to believe. Now I need to do more research.

We've run the Wilwoods before. We used to sell them. Best thing around and a stock caliper aint even close in stopping power. The clamping force is more even with 4 pistons compared to one piston on a slider caliper. I think you'll be happy with them once you figure out what sizes you need.

[John Kunkel]

Originally Posted by dwc43

Best thing around and a stock caliper aint even close in stopping power. The clamping force is more even with 4 pistons compared to one piston on a slider caliper.

Just another in a long list of things you're wrong about.

The biggest Dynalites have a 1 3/4" piston while the Cordoba has a 2 3/4" piston. Contrary to popular belief only two of the pistons in a 4-piston rigid caliper actually apply clamping force, the two on the opposite side only act to back up the other two.

So, two 1 3/4" pistons have a total surface area of 4.81 sq. in. while the single 2 3/4" piston has a surface area of 5.94 sq. in.

The formula to determine clamping force is to simply multiply the total piston surface area by the hydraulic pressure provided by the master cylinder.

Using 1000 psi as an example, the Dynalite will provide a clamping force of 4810 pounds while the Cordoba will be 5940 pounds.

If the smaller Dynalite caliper with the 1 3/8" piston is used the clamping force is only 2970 pounds. (half the Cordoba) If the newer 75 mm floating caliper is used the clamping pressure would be 6840 pounds.

Bottom line, all other factors (pressure, disc diameter) being equal the single-piston sliding caliper will outperform the 4-piston rigid.

[1973Swinger]

Heres the skinny on different braking systems:

http://www.hotrodheaven.com/tech/bra...kes1_index.htm

[SSHAKERR]

As usual, when I post a question, different opinions leave me more confused than I was before I posted. I am getting the feeling that the stock caliper would be best for a single hard stop, But multiple hard stops may be better with the 4-piston calipers, Besides, Doesnt the Viper 4-piston caliper still have a smaller overall surface area too? wouldnt you find a better caliper on a viper than on an old cordoba? Then again, I am sure stopping with single piston calipers on vented and crossdrilled 11.75 x1 rotors would still be worlds cooler than on the thinner and smaller OE rotors that My big block cuda didnt even have. (11" drums all around)

OK, too tired to think about it any more today. G'nite.

[John Kunkel]

Originally Posted by SSHAKERR

As usual, when I post a question, different opinions leave me more confused than I was before I posted.

There is no difference of opinion, weed out the provable facts of brake theory from the bogus information. The numbers don't lie.

I am getting the feeling that the stock caliper would be best for a single hard stop, But multiple hard stops may be better with the 4-piston calipers,

The clamping force won't change with repeated stops unless the hydraulic pressure drops due to fluid boiling. Heat dissipation is better with an aluminum caliper but you'll never see the difference in street driving.

If you want the ultimate in clamping power look at the kits that use the GM/Dodge truck 75MM (2.95") single calipers; ECI makes such a kit.