At A crossroads on whether or not to go Hydraboost - Lateral-g Forums

rogue · #1 06-01-2009, 06:13 PM

My car is a non power steering car with 13" Brakes up front and 12" Brakes in the rear. Usual Suspect conversion kits from Ricks...

I'm not getting enough power from the booster to the brakes and cannot get the car to lock up the tires unless I pump up a lot of pressure before a hard brake....

Recently saw that crash at the autocross of the car that crashed due to the engine stalling and hydroboost failing and it got me thinking. I'm going to get some vacuum readings off my stock zz502 this weekend and see if I'm getting enough vacuum to run a booster.

If I have enough Vacuum should I just run a dual diaphram 8" Booster or should I bite the bullet and do a hydraboost setup and add power steering as well...

$1800 or so vs $350 or so... Pretty big price difference.

I've heard from a few people the zz502 doesn't put out much vacuum. Will see on saturday.

XLexusTech · #2 06-01-2009, 06:35 PM

x2 on the feeling I got after seeing that Nova smashed like that. Made me think Manual was the say to go.

Not made any choices yet but it sure made me step back and think..

**XcYZ** · #3 06-01-2009, 06:55 PM

The engine died and the assist didn't work? Something is wrong there... the nitrogen reserve cylinder accumulates and stores pressure so if you lose power steering you would still have some assist.

Several years ago when I had my car at the strip with the 434, it died as I went through the lights. I had 3 full stabs at the brakes with power assist with the engine off (going about 120mph), after that I just had a hard pedal.

rogue · #4 06-01-2009, 07:05 PM

Quote:

Originally Posted by XcYZ

The engine died and the assist didn't work? Something is wrong there... the nitrogen reserve cylinder accumulates and stores pressure so if you lose power steering you would still have some assist.

Several years ago when I had my car at the strip with the 434, it died as I went through the lights. I had 3 full stabs at the brakes with power assist with the engine off (going about 120mph), after that I just had a hard pedal.

Thats the theory behind the system...

from the autocross thread:

https://lateral-g.net/forums/show...19&postcount=1

My problem is, my car doesn't have power steering so I'd have to add power steering pump, all bracketry, just for the hydroboost. And at that point, I might as well add Power Steering and a 12:1 ratio box. It adds up pretty quick. $2000 just to lock up my brakes, lose some power, and add more things that can fail at the track.

Or just find a booster that works for $300 and call it a day.

Would I be able to run a manual master with my OEM style calipers?

Fronts:

Rears:

I just want a nice predictable solid pedal, I don't care if it requires some strength because I'm a big guy, but I need full lock up and I need to rely on my brakes on track days.

For now I baby the car because the brakes are the weak link...

Vegas69 · #5 06-01-2009, 08:33 PM

ZZ502 should put out enough vacuum for power brakes. That's a teeny little cam in that thing.

rogue · #6 06-01-2009, 08:57 PM

Quote:

Originally Posted by Vegas69

ZZ502 should put out enough vacuum for power brakes. That's a teeny little cam in that thing.

thats another part of the equation. I doubt the cam in the motor will stay stock for much longer. I'll eventually be doing heads cam/intake manifold...

Long term I suppose a hydroboost/electric booster setup would be best, I'm just having a hard time dropping the money on it when I'd rather use it on track days...

Mick Mc · #7 06-02-2009, 08:16 AM

Quote:

Originally Posted by rogue

My car is a non power steering car with 13" Brakes up front and 12" Brakes in the rear. Usual Suspect conversion kits from Ricks...

I'm not getting enough power from the booster to the brakes and cannot get the car to lock up the tires unless I pump up a lot of pressure before a hard brake....

Recently saw that crash at the autocross of the car that crashed due to the engine stalling and hydroboost failing and it got me thinking. I'm going to get some vacuum readings off my stock zz502 this weekend and see if I'm getting enough vacuum to run a booster.

If I have enough Vacuum should I just run a dual diaphram 8" Booster or should I bite the bullet and do a hydraboost setup and add power steering as well...

$1800 or so vs $350 or so... Pretty big price difference.

I've heard from a few people the zz502 doesn't put out much vacuum. Will see on saturday.

Manual brakes work great, BUT like every thing else they need to be set up correctly.
What car are we talking about?
If you get the pedal ratio correct the brakes will work great.

For example there is a huge difference in pedal ratios of Camaros and Chevelles and power and non-power.
Manual can be made to work, but you need to do the math.
A power set up is very forgiving. If the ratio is incorrect or the master cylinder is under or over sized the power sort of covers it up.

Your system sounds like there are other issues first to deal with.

Find a dirt road and see if you can lock up the rear brakes.

My guess is there is something else in the system that needs fixing.

A good brake bleeding is the first place to start. If you're a little unsure about bleeding take it to a brake shop, most of them have a very cool 'power bleeder'. Paul from Hydratech has a great article on his website about bleeding brakes (Hydra-boost systems are very sensitive to bleeding issues).

Take a look at the brake pedal itself. Are there several holes for the rod that goes to the master cylinder? Which hole is being used?

Take a look at all of the brake lines, are they stock or aftermarket, are they rubber or stainless steel, are they smashed or twisted. The brake line that runs under the engine next to the crossmember is notorious for getting beat up, and gets hot too.
If you have flexable lines at each wheel, how long are they and are they braided stainless steel. Are they -3 or -4?

You say "your not getting enough power from the booster" which booster and master cylinder are you running now?

If the car is older, does it have the combination valve, or is it the later model with a proportioning valve? If you purchased the booster and master cylinder together I assume it had a proportioning valve already plumbed?

Mick

Mick Mc · #8 06-02-2009, 08:33 AM

The Nova crash

Something seems wrong.
The engine dies, and the brakes don't work?

Did the engine die and the driver pump the brakes a bunch and it still did not stop?
Hydra-Boost will always give you a few more pedal pushes, thats what the nitrogen reserve is for. No brake system would be designed and mass produced and installed on cars and very large trucks and sold to the public without some sort of safety feature in case the engine died.

Maybe the engine died, he was trying to turn the car and stomp on the brake pedal all at the same time and in the blink of an eye he hit the barrier, I could believe that.
But the engine died and no brakes and he hit the barrier, I don't believe that.

As the late Paul Harvey would say "the rest of the story".
I'm waiting for the rest of the story.

Mick

DRJDVM's '69 · #9 06-02-2009, 08:49 AM

In the turn he crashed on, there wasnt alot of extra space..... there was a small S-curve and then a long sweeping turn left....... he went straight rather than make the sweep. The course was pretty small and tight and the barried in that corner wasnt far off the track.

When I did my '69 the guys at BAER convince me there was no need to get power brakes.... they make the pedal feel easier but dont stop the car any better.

On the Cuda I am planning on the hydroboost

Blake Foster · #10 06-02-2009, 09:05 AM

Both of these have manual brakes Pauls (the green one) has Wilwood superlite 4 piston front and Dynalite 4 piston rear with a Wilwood 1" master.
and it stops, you can lock it up but it is actually easier to modulate when they lock up over say the TransAm we did that has Hydroboost. My Car ( the white/grey one) is a drag car and runs the wilwood 10.75" 4 piston front and 11" 4 piston rear with a wilwood 7/8" master ( i wanted more line pressure to hold the car in the burn out box on the line lock so that is why the smaller master) it weighs 3200 with me. and it stops from 137mph. i dont even have a prop valve in it, i have had 4 drag cars with different brake systems the last one was a super comp 2000 mustang with the same brake system as my camaro and it would stop from 168 mph no problem.
Scott i agree with who ever said the Chevelle brake system must not have been set up correctly.
the other thing to consider is how "YOU" like the brakes to feel, maybe the guy who owned the chevelle was an ape and had really strong legs??? i tell guys all day long that you may have to change tha master a couple times to get the "Feel" correct for "YOU"
theres .02 more