Wilwood 4-piston VS 6-piston in front.

[thiswildbronco]

So...

Took me a while to notice, but the front brake kit spec'd for me by Wilwood (which I bought months ago) is a 4-piston kit (WID-140-13305-DR). In speaking with Wilwood recently, they made the case that there really isn't going to be a measurable difference between 4 and 6 pistons. I'm not "racing" and while my truck will be a high performance setup, they made it sound like it wouldn't really be worth the trouble. I have not yet installed the front kit.

I've seen plenty of 6-piston front brakes in other builds. Just would like to know what y'all think of this.

Thanks!!!

Duke.

 

[Broncobowsher]

Diameter of the 4 pistons, diameter of the 6 pistons. Are they the same size pistons or are they staggered sizes?

I'm going to say 4 pistons will be just fine.

 

[garberz]

Diameter of the 4 pistons, diameter of the 6 pistons. Are they the same size pistons or are they staggered sizes?

I'm going to say 4 pistons will be just fine.

Yes, especially when the rotors are the same diameter.

Mark

 

[SteveL]

I thought I've read the 6 piston are a bigger set up requiring 17" rims

 

[StnePny]

When I reviewed their spec sheets on the 4 - piston vs. 6 - piston (in front of their Rep., at a Trade Show), I pointed out that the 4 - piston hard more surface area than the 6 - piston.

 

[ntsqd]

Piston area is piston area and none of the wilwood calipers come close to the T-Bird caliper in piston area. If the m/c is sized to suit them, then it doesn't matter but if a stock size m/c your overall brake leverage ratio will be off.

 

[Apogee]

Wilwood is not wrong, as the caliper piston area of the 4-piston kit you have is 4.80 square inches and the comparable Forged Narrow Superlite 6-piston calipers are available with 3.46, 4.04 and 4.86 square inches of piston area. Given the loading scenario on a caliper, center pistons tend to be prone to getting pinched in severe-duty applications, so there are actual benefits to 4-pistons versus 6-pistons if you want to talk about deflection and deformation of the piston bores...this is why Wilwood no longer sells their W6A calipers and transitioned that application into their AERO6 line with the large bridge supports/reinforcements.

As with any system, supply adequate pressure to the calipers will require the proper master cylinder, pedal ratio, booster (if running one), etc to get good brake function.

 

[68ford]

The 6 pistons are for 15in wheels and 4 pistons are 17in and up kits. The 6 piston is narrow dynalite and has small pistons. The 4 piston is a superlite, step up from dynalite. You can get a superlite with large pistons and have more surface area than a Tbird caliper. I have those on the rear of my bronco. I have the 6 piston dynalite fronts(normal 15in she'll kit). Spoke to Wildwood and they said they make a large piston 6 piston dynalite which has more surface area than a Tbird caliper, but you have to special order it. Was not avail when I got mine. I can honestly say going from stock 76 calipers to the 6 piston wilwoods made very little difference. They're better, but not much. Luckily I run dual parallel Masters and adjusted the bias more to the front since the rear was so much better.

 

[Apogee]

The 6 pistons are for 15in wheels and 4 pistons are 17in and up kits. The 6 piston is narrow dynalite and has small pistons. The 4 piston is a superlite, step up from dynalite. You can get a superlite with large pistons and have more surface area than a Tbird caliper. I have those on the rear of my bronco. I have the 6 piston dynalite fronts(normal 15in she'll kit). Spoke to Wildwood and they said they make a large piston 6 piston dynalite which has more surface area than a Tbird caliper, but you have to special order it. Was not avail when I got mine. I can honestly say going from stock 76 calipers to the 6 piston wilwoods made very little difference. They're better, but not much. Luckily I run dual parallel Masters and adjusted the bias more to the front since the rear was so much better.

Pretty sure you mean the 6-piston Dynapro kit for the 12.19" x .81" rotors, as Wilwood does not offer a 6-piston Dynalite caliper. The 4-piston Forged Narrow Superlite calipers are definitely a step up from both the Dynalite and Dynapro calipers in terms of stiffness and pad size, and is what they use on the standard Bronco kits with the 12.88" and 14.00" rotor kits. That said, you could easily substitute the 6-piston calipers into the kit for the additional charge, but aside from slightly more uniform pad contact pressure, I don't know that you'd actually notice any difference from the driver's seat either way.

 

[StnePny]

When I reviewed their spec sheets on the 4 - piston vs. 6 - piston (in front of their Rep., at a Trade Show), I pointed out that the 4 - piston hard more surface area than the 6 - piston.

(Wilwood redesigns its caliper every couple of years...)

When the Wilwood Caliper Kits came out a few years ago, it was the 6 - piston caliper that took a 17" wheel.

There design now is to use a 6 - piston caliper on a 15" wheel and using a redesigned larger 4 - piston on the 17" wheel

The new designed 4 - piston caliper has a nice size piston in it.

 

[73azbronco]

4 piston, fewer parts, fewer chance of issues.

 

[thiswildbronco]

Wilwood is not wrong, as the caliper piston area of the 4-piston kit you have is 4.80 square inches and the comparable Forged Narrow Superlite 6-piston calipers are available with 3.46, 4.04 and 4.86 square inches of piston area. Given the loading scenario on a caliper, center pistons tend to be prone to getting pinched in severe-duty applications, so there are actual benefits to 4-pistons versus 6-pistons if you want to talk about deflection and deformation of the piston bores...this is why Wilwood no longer sells their W6A calipers and transitioned that application into their AERO6 line with the large bridge supports/reinforcements.

As with any system, supply adequate pressure to the calipers will require the proper master cylinder, pedal ratio, booster (if running one), etc to get good brake function.

I'll be running a new Hyrdatech setup, so I think I am covered there. Thanks!

 

[thiswildbronco]

Thanks for all the replies!!! I am sufficiently reassured that, particularly given that I am running 17" rims and 6 piston is not even spec'd for a 17, that my 4-piston setup is entirely adequate.

 

[duffymahoney]

I am currently trying to figure out wilwood 4 pistons on the front, or 6 pistons.

Options for my 17" wheels

Forged Narrow Superlite 6R Big Brake Front Brake Kit and Forged Narrow Superlite 4R Big Brake Rear Parking Brake Kit

D8-4 Truck Front Brake Kit and Dynapro Lug Mount Rear Parking Brake Kit

The Superlites are 50% more money. Must bigger pads, but pistons are smaller.