Hydratech power booster

[gsxrken 21]

I took the plunge on one of hydratech's boosters. With my 248* @.050 duration camshaft, I wasn't making consistent vacuum for the power brakes, and didn't like the effort associated with the manual pedal and MC I tried next.

 

It ain't cheap. And the little ancillaries like fittings, aeroquip teflon hose, and the very short GM master cylinder required to clear the shock tower add up. Hopefully this is the last piece of the brakes puzzle.

 

No driving impressions yet, as the car is still in the air as I bleed the PS and brake lines. And I'm traveling this week so it won't be for another week or so. But I thought I'd post a few progress pics...

[buening 63]

Nice!!!

[Grabber70Mach 107]

Looking good. :cool:

[gsxrken 21]

Thanks. I removed the CNC tandem master that I tried last year. It has the balance bar that eliminates the need for a proportioning valve. I had installed a manual pedal (a gift from Johnpro from VMF for those who knew him) but was just never happy with the effort it required. I guess I am very spoiled by modern "big-toe" power brakes.

 

[buening 63]

I've been warned to not use a dual M/C with balance bar for street driven vehicles. Here was the discussion: http://mustangforums.com/forum/classic-mustangs/599994-gorilla-performance-bal-bar-balance-bar-dual-mcs-no-booster-required.html

[fvike 173]

I've had a Hydraboost (also from Hydratech) for a few years now. You will be pleasantly surprised :) Awsome breaking power.

[fvike 173]

I've had a Hydraboost (also from Hydratech) for a few years now. You will be pleasantly surprised :) Awsome breaking power.

[69StangRestomod 11]

never any problems with losing power steering while braking? my boss seems to think that would be an issue, personally I just like the look of hydroboosts much more than that of vacuum boosters

[69StangRestomod 11]

never any problems with losing power steering while braking? my boss seems to think that would be an issue, personally I just like the look of hydroboosts much more than that of vacuum boosters

[fvike 173]

I had some "crosstalk" between brakes and steering at the beginning, but as the air (microbubbles) went out of the ps fluid it has been less of a problem. I'm not saying it's completly gone, but it's not anything that is bothering me. I've only experienced it on low rpm, as the load on the power steering is higher.

[fvike 173]

I had some "crosstalk" between brakes and steering at the beginning, but as the air (microbubbles) went out of the ps fluid it has been less of a problem. I'm not saying it's completly gone, but it's not anything that is bothering me. I've only experienced it on low rpm, as the load on the power steering is higher.

[gsxrken 21]

I had some "crosstalk" between brakes and steering at the beginning, but as the air (microbubbles) went out of the ps fluid it has been less of a problem. I'm not saying it's completly gone, but it's not anything that is bothering me. I've only experienced it on low rpm, as the load on the power steering is higher.

 

Good to hear. That's where I'm at right now with the car still on jackstands. I still get some foamy fluid after cycling the steering wheel lock to lock and hitting the brakes numerous times. Less and less, though, and the pump is quiet again.

 

To the other poster, you can remind your friend that many OEMs have gone with hydroboost for either packaging constraints or high assist PSI needs; if they got it by their product liability lawyers you can bet it's probably good enough. With respect to stalls, power steering line failures, or other SHTF scenarios, yes they can happen, but the booster has an accumulator that stores pressure good for 2 separate brake applications before you are standing on the pedal with no assist at all. (Sometimes that was how my vacuum booster would feel anyway in an autocross after a few rapid braking applications were performed before the engine RPMs came up again and replenished the vacuum.)

 

Not everyone needs one, and if you don't, they are an unnecessary expense. I've just had it with my old variable-assist power brakes (never really could trust how hard they were going to hit) or the high-effort manual. I'm hoping that the hydroboost, while complex and somewhat expensive, is the "nuclear option" for me and I can start thinking more about the corner than how my brakes will be this time.

[gsxrken 21]

I had some "crosstalk" between brakes and steering at the beginning, but as the air (microbubbles) went out of the ps fluid it has been less of a problem. I'm not saying it's completly gone, but it's not anything that is bothering me. I've only experienced it on low rpm, as the load on the power steering is higher.

 

Good to hear. That's where I'm at right now with the car still on jackstands. I still get some foamy fluid after cycling the steering wheel lock to lock and hitting the brakes numerous times. Less and less, though, and the pump is quiet again.

 

To the other poster, you can remind your friend that many OEMs have gone with hydroboost for either packaging constraints or high assist PSI needs; if they got it by their product liability lawyers you can bet it's probably good enough. With respect to stalls, power steering line failures, or other SHTF scenarios, yes they can happen, but the booster has an accumulator that stores pressure good for 2 separate brake applications before you are standing on the pedal with no assist at all. (Sometimes that was how my vacuum booster would feel anyway in an autocross after a few rapid braking applications were performed before the engine RPMs came up again and replenished the vacuum.)

 

Not everyone needs one, and if you don't, they are an unnecessary expense. I've just had it with my old variable-assist power brakes (never really could trust how hard they were going to hit) or the high-effort manual. I'm hoping that the hydroboost, while complex and somewhat expensive, is the "nuclear option" for me and I can start thinking more about the corner than how my brakes will be this time.

[69StangRestomod 11]

one more q to the OP, I see the TCP rack steering shaft, is it a power rack? what pump are you using and are you moderating the psi to the rack via a valve or KRC pump?

[69StangRestomod 11]

one more q to the OP, I see the TCP rack steering shaft, is it a power rack? what pump are you using and are you moderating the psi to the rack via a valve or KRC pump?

[gsxrken 21]

one more q to the OP, I see the TCP rack steering shaft, is it a power rack? what pump are you using and are you moderating the psi to the rack via a valve or KRC pump?

 

TCP power rack. I use the KRC pump and bolt on tank. You can see the pump in this image:

 

Pump pressure side goes straight to booster, then booster goes to rack. When the brake pedal is not depressed, the fluid flows right through in bypass mode down to the rack. I teed the booster return into the rack return to the pump reservoir.

 

You asked about PSI moderation but I am only familiar with the flow reducers they use, which are interchangeable. http://www.krcpower.com/flowvalves.html

 

I use the stock one. According to Paul at Hydratech, the booster only uses about 2 tablespoons of fluid when the brakes are applied. I can't see that bumping me into a different flow valve, but if I find I get steering feedback when I am simultaneously braking, then I may start juggling valves.

[gsxrken 21]

one more q to the OP, I see the TCP rack steering shaft, is it a power rack? what pump are you using and are you moderating the psi to the rack via a valve or KRC pump?

 

TCP power rack. I use the KRC pump and bolt on tank. You can see the pump in this image:

 

Pump pressure side goes straight to booster, then booster goes to rack. When the brake pedal is not depressed, the fluid flows right through in bypass mode down to the rack. I teed the booster return into the rack return to the pump reservoir.

 

You asked about PSI moderation but I am only familiar with the flow reducers they use, which are interchangeable. http://www.krcpower.com/flowvalves.html

 

I use the stock one. According to Paul at Hydratech, the booster only uses about 2 tablespoons of fluid when the brakes are applied. I can't see that bumping me into a different flow valve, but if I find I get steering feedback when I am simultaneously braking, then I may start juggling valves.

[fvike 173]

I changed to the highest flowing one (3.17 GPM), but I can't remember if i'm still running it, or the original one (2.11 GPM iirc). I'll check for you.

[fvike 173]

I changed to the highest flowing one (3.17 GPM), but I can't remember if i'm still running it, or the original one (2.11 GPM iirc). I'll check for you.

[69StangRestomod 11]

awesome, thanks. we put a TCP power rack in a 69 with a regular pump and it was way way touchy (although personally i think alot of it has to do with the wide tires up front as well). Heidts makes an adjustable valve to moderate what gets to the rack, but I think fo mine I will do what TCP recommends and use a KRC pump. I personally think hydrboosts just look better than vacuum units IMO.

 

Thanks again.

[69StangRestomod 11]

awesome, thanks. we put a TCP power rack in a 69 with a regular pump and it was way way touchy (although personally i think alot of it has to do with the wide tires up front as well). Heidts makes an adjustable valve to moderate what gets to the rack, but I think fo mine I will do what TCP recommends and use a KRC pump. I personally think hydrboosts just look better than vacuum units IMO.

 

Thanks again.

[fvike 173]

I checked, I use the stock flow valve.

[fvike 173]

I checked, I use the stock flow valve.

[gsxrken 21]

Well, the car is on the ground and the brake effort is amazingly easy. I did a few hard stops to test and see whether I need to play with the proportioning valve. Boy do I have to – but the effort to achieve full lock up of my rear tires (and start to rotate the car at 40MPH, yikes) was perfect. I still need to tune the prop valve. In a parking lot they are pretty grabby, but I think that is just my uncalibrated foot. I’m still used to the manual configuration. What I’ve noticed already is that I can concentrate on my surroundings more than I used to. With the manual setup, I was somehow always surprised at how hard I had to press to get the tires to start howling like they do just before they skid, and that would drain attention. Now it’s better than my BMW.

 

I could have bought a pre-70 coupe for the money I have thrown at my brakes, 1/3 of which was just doing things twice or three times. Actually this is my fifth master cylinder- I’m not proud to admit that! But the current combo of Wilwood 6 piston 13” fronts, Wilwood 4 piston 12” rears, hydratech booster, and the short Chevy S10 1” master seems to be nirvana. I have a track day next Saturday at NJMP so we’ll see how it does in anger. I want to get a few more shake down runs under my belt before then. Also need to chase down a coolant leak. Since it awoke from winter hibernation, I now have coolant puddling on the timing cover, and weeping onto the floor. And it’s not the hoses or t-stat gasket.