WTF? C2/C3 Wilwood direct replacement caliper

HB is not heavier than that clunky stupid vac system....

I think that stock vac booster has too much play in the design, so the pedal can go to the floor way before the brakes are locked up, typically, it took a serious stab to lock them up something I could never do by trying....
but the pedal would be on the floor with the last inch or so being harder to apply but never would lock the brakes by trying....

I tore the old booster apart to see WTF was going on that I suffered with for some 12 years, found NOTHING....all seals, diaphram, vacuum sucked large when pulling the check valve off the gasket mount...inside it seemed fine, but I did notice a tough spring between the input shaft and output piston...interesting, but no idea why it was there...I figger it was most if not all of the problem, and from the feel of other vac boosters, it must be common to other ones too...part of the design....

all I know is I have some 2" of pedal travel, and it NEVER goes to the floor, plenty of room to spare, so much so, I need pull the m/cyl and see how lo that pedal can go, that a way maybe I can lower the brake pedal a bit more....if I don't need the extra room in case of failure, may as well put the pedal lower....NO??

:thumbs:
 
Yes it is, quite a bit too. The vacuum booster is a pretty lightweight piece of equipment compared to the hydrobooster.

I too feel the HB is a bandaid that masks the shortcomings of the stock caliper. These wilwoods address all the issues that make the stock caliper crappy.
 
Twin_Turbo said:
Yes it is, quite a bit too. The vacuum booster is a pretty lightweight piece of equipment compared to the hydrobooster.

I too feel the HB is a bandaid that masks the shortcomings of the stock caliper. These wilwoods address all the issues that make the stock caliper crappy.
Click to expand...

Yep. The VBandP Hydroboost kit is like $900. The Wilwoods are $1,200 a set. No brainer for me.:D
 
Twin_Turbo said:
Yes it is, quite a bit too. The vacuum booster is a pretty lightweight piece of equipment compared to the hydrobooster.

I too feel the HB is a bandaid that masks the shortcomings of the stock caliper. These wilwoods address all the issues that make the stock caliper crappy.
Click to expand...

I did not put them on a scale as we didn't even HAVE one when I did the changeover....I was shocked how heavy that HB was so I hefted the old booster in one hand the HB in the other, and judged them to be nearly the same...so maybe 5 lbs at most?? if that....doubtful, Hell, I gained 20 lbs by being lazy assed retired recently...:eek:

so show me just HOW these aluminum versions of the vette caliper, which look for all the world like the same O ring 4 piston opposed design we have now....HOW are they supposed to magically CURE the inherent brake design problems??? they aint....lighter by some 5 lbs/wheel for sure, O ring's a O ring guys, 4 pistons is same, just the material changed, I can see them costing 400 bus per CAR, but not 3-400 bux EACH......

the one reason I never went to a single piston floating caliper design off some car with same rotor width, but aluminum and lighter was that for all the work, the only thing eliminated was that air pump problem which was fixed by O rings....

so you all tell ME, how with not even popping a line, my brakes went from stupid to GREAT just by replacing the booster.....

:eek: and I know I must be right about it, as it's been some 3 years now, damn things as hard now as when first got the HB in....only 6 X longer than the previous longest service interval....:thumbs: and you all tell me it's not the HB unit?? bullshit.....
 
The HB is heavier by a lot more than 5 lbs. I sold mine so don't have one to weigh. Larry has one I think, I remember him posting a for sale here??

O rings is not O rings. it's the way the piston is sealed. Somehow the Delco guys designing the corvette caliper had a brain fart and put the lip seal groove in the piston and then used a cast iron bore. Okay, so you can get stainless sleeved calipers. But STILL, the way it is set up calls for a very wide tolerance for the aluminum piston to bore, much larger than when you have a stainless piston and a SQUARE groove in the caliper and use a SQUARE o ring seal like most, if not all other calipers have. It's also much easier to machine and polish a stainless piston to a smooth microfinish that seals perfectly, much easier than doing it for an o ring sleeve. The design with the seating groove in the caliper also allows you to run a cupped piston that has a thin cylindrical face that pushes against the pad, instead of a fully closed faced aluminum piston. The alu piston transfers heat easily, the stainless has a cupped design and as such when pressing against the pad only makes contact with the edges of the cylinder shape, the innards is filled with air. A very good insulator, so not only lightweight, easily machined and micropolished but also much less heat transfer.

These wilwood pistons take all the good things of the C3 caliper (piston size, pad size) and combine this with a modern lightweight caliper with stainless cupped pistons.

As for a HB, increasing the line pressure goes a long way in band aiding a faulty brake setup.
 
Twin_Turbo said:
The HB is heavier by a lot more than 5 lbs. I sold mine so don't have one to weigh. Larry has one I think, I remember him posting a for sale here??

O rings is not O rings. it's the way the piston is sealed. Somehow the Delco guys designing the corvette caliper had a brain fart and put the lip seal groove in the piston and then used a cast iron bore. Okay, so you can get stainless sleeved calipers. But STILL, the way it is set up calls for a very wide tolerance for piston to bore, much wider than when you have a SQUARE groove in the caliper and use a SQUARE o ring seal like most, if not all other calipers have. It's also much easier to machine and polish a stainless piston to a smooth microfinish that seals perfectly, much easier than doing it for an o ring sleeve. The design with the seating groove in the caliper also allows you to run a cupped piston that has a thin cylindrical face that pushes against the pad, instead of a fully closed faced aluminum piston. The alu piston transfers heat easily, the stainless has a cupped design and as such when pressing against the pad only makes contact with the edges of the cylinder shape, the innards is filled with air. A very good insulator, so not only lightweight, easily machined and micropolished but also much less heat transfer.

These wilwood pistons take all the good things of the C3 caliper (piston size, pad size) and combine this with a modern lightweight caliper with stainless cupped pistons.

As for a HB, increasing the line pressure goes a long way in band aiding a faulty brake setup.
Click to expand...

CASE CLOSED:smash::smash::smash:
 
Hydoboost unit 14lbs

Booster 8.5 lbs

Hey, I have an idea. Some one should buy my Hydroboost and do a comparison!:bump:
 
Twin_Turbo said:
The HB is heavier by a lot more than 5 lbs. I sold mine so don't have one to weigh. Larry has one I think, I remember him posting a for sale here??

O rings is not O rings. it's the way the piston is sealed. Somehow the Delco guys designing the corvette caliper had a brain fart and put the lip seal groove in the piston and then used a cast iron bore. Okay, so you can get stainless sleeved calipers. But STILL, the way it is set up calls for a very wide tolerance for piston to bore, much wider than when you have a SQUARE groove in the caliper and use a SQUARE o ring seal like most, if not all other calipers have. It's also much easier to machine and polish a stainless piston to a smooth microfinish that seals perfectly, much easier than doing it for an o ring sleeve. The design with the seating groove in the caliper also allows you to run a cupped piston that has a thin cylindrical face that pushes against the pad, instead of a fully closed faced aluminum piston. The alu piston transfers heat easily, the stainless has a cupped design and as such when pressing against the pad only makes contact with the edges of the cylinder shape, the innards is filled with air. A very good insulator, so not only lightweight, easily machined and micropolished but also much less heat transfer.

These wilwood pistons take all the good things of the C3 caliper (piston size, pad size) and combine this with a modern lightweight caliper with stainless cupped pistons.

As for a HB, increasing the line pressure goes a long way in band aiding a faulty brake setup.
Click to expand...

Marck, I tended to take your position on it, and Norval/others were talking HB for a long time before I finally said 'fuck it' and tried one, I was doubtful also....but no air is NO AIR in the system, if there was, the pedal still would have to deflect the same amount no matter the booster, but such was NOT the case....the soft unsure feeling is in the damn booster, where I dunno, but in there somehow by design...as they are all much the same....from Gm to Ford, to Mopar....so you trying to say somehow that HB unit is masking air in the lines for some 3 years now?? no way man, no way...

you do see my point, that for X air in the system, it's going to take Z amount of m/cyl piston travel to compress it and activate the brakes, well, explain how just replacing the booster brought the pedal travel up to nearly 2" at most now, instead of down to the floor???
 
I forgot to add, not only does the square o ring most likely seal better, I can see how it would be more effective at keeping the piston from cocking in the bore also, soemthing C3 calipers do tend to do.

You don't want air in the system period, with the square o ring you will not get air in the system. With the stainless piston you won't have a corroded piston compromising the seal.

IMO the HB feels like an overassisted setup with no pedal feel whatsoever. I hate it as much as I hate overassisted steering.
 
Twin_Turbo said:
I forgot to add, not only does the square o ring most likely seal better, I can see how it would be more effective at keeping the piston from cocking in the bore also, soemthing C3 calipers do tend to do.

You don't want air in the system period, with the square o ring you will not get air in the system. With the stainless piston you won't have a corroded piston compromising the seal.

IMO the HB feels like an overassisted setup with no pedal feel whatsoever. I hate it as much as I hate overassisted steering.
Click to expand...

Sez Mr. Armstrong who works out every day....:pprrtt::gurney:
 
Twin_Turbo said:
IMO the HB feels like an overassisted setup with no pedal feel whatsoever. I hate it as much as I hate overassisted steering.
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That's what i've always been afraid of. I bought a used hyro to install but never bothered.

When i'm out on the road course all jacked up a little too much pressure and a locked wheel could send me off the course or into a wall. They never lock all at once either.

Overassisted steering makes it very hard to determine the slip limit of the front wheels in a turn. Not a good thing. All these steeroid, jeep box, hydroboost advocates need to understand this.
 
Well if you used to sloppy steering/brakes you used to it, what can I say???:bonkers::devil::beer::beer:
 
turtlevette said:
All these steeroid, jeep box, hydroboost advocates need to understand this.
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Steeroids doesn't feel over assisted, I like the wayit feels when it comes to the amount of assist. But for the rest, it has poor self centering, no real feedback, feels mushy and the input shaft is scary as hell.

I don't know how the jeep box handles, I heard it felt over assisted too. If it wasn't for that I would be all over it and put one on Xanders car. That one has a fully rebuilt stock system now.
 
Assist, who needs assist?

I have manual brakes which stop me pretty good!. Hard pedal and good feel. If I need to stop quicker, I just press harder.
 
BBShark said:
Hydoboost unit 14lbs

Booster 8.5 lbs

Hey, I have an idea. Some one should buy my Hydroboost and do a comparison!:bump:
Click to expand...

Plus the weight of the power steering pump, lines and the increased engine drag from the power steering pump.
 
You guy's might as well give it up. If Gene has it that is the way to go,if he does not it is a waste of time.



CASE CLOSED!!!!!!!!!!!!!! :suspicious:
 
Twin_Turbo said:
turtlevette said:
All these steeroid, jeep box, hydroboost advocates need to understand this.
Click to expand...

Steeroids doesn't feel over assisted, I like the wayit feels when it comes to the amount of assist. But for the rest, it has poor self centering, no real feedback, feels mushy and the input shaft is scary as hell.
Click to expand...

You say the amount of assist feels proper but then say it has no real feedback and feels mushy. Maybe we're splitting hairs but the bottom line is its no good for performance driving.
 
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These 2000-2003 model GrandAms are very overassisted, first time I drove one of those I was shocked how easy the steering wheel would turn. No resistance whatsoever, felt like driving on ice.
I hope that with wider tires this mid 90's GrandAm rack works better in my '79.... we'll see....
 
turtlevette said:
Twin_Turbo said:
turtlevette said:
All these steeroid, jeep box, hydroboost advocates need to understand this.
Click to expand...

Steeroids doesn't feel over assisted, I like the wayit feels when it comes to the amount of assist. But for the rest, it has poor self centering, no real feedback, feels mushy and the input shaft is scary as hell.
Click to expand...

You say the amount of assist feels proper but then say it has no real feedback and feels mushy. Maybe we're splitting hairs but the bottom line is its no good for performance driving.
Click to expand...


It is not over assisted indeed, the wheel is pretty hard to turn. Harder than 0with the stock unit. About the same as a C4 corvette or a 3rd gen. The feel is uncommunicative though with the play in the input shaft due to all those joints and the rack being rubber mounted, the brackets flexing and most likely the frame too. it;s no good for performance or sporty street driving at all. IMO it's downright scary for instance when you need to do some quick evasive maneuvers. What bothers me even more is the lack of self centering, you have to center the wheel yourself and it's NOT a problem with the caster settings on the car.
 
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