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Old 02-24-2023, 09:04 AM
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Mr Anonymous Mr Anonymous is offline
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Hydroboost? I wouldnt recommend it. Not only is the pedal feel really bad, your "assist" can be affected by something as dumb as the PS belt tension. I've also panic stopped a hydroboosted GMC crew cab that was pulling an open trailer with a car on it. I dont ever want to be in that situation again. EVER. An evasive maneuver combining heavy steering effort and heavy braking effort is a bad deal.

Not a fan of vacuum cans, for the same reasons as already mentioned.

I have more than one car with manual brakes, and one of them is a disc/drum street car. With the right combination of parts, the pedal feel and feedback is hard to beat in my opinion.

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  #2  
Old 02-24-2023, 11:46 AM
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Formulajones Formulajones is offline
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2 cars and 2 trucks here with hydroboost and never an issue. Love the pedal assist. Works as intended, rock solid pedal feel on all of them.

Used to run vacuum cannisters with "OK" results but still only good for about 2 stops when idling around a parking lot. Then tried electric vacuum pumps, got really tired of the noise they created.. Went through all that for years before throwing in the towel for hydroboost and now won't ever look back.

On a hot street car it's either going to be power brakes with hydroboost or a manual brake system. That's it.

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Old 02-24-2023, 01:46 PM
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Quote:
Originally Posted by Mr Anonymous View Post
Hydroboost? I wouldnt recommend it. Not only is the pedal feel really bad, your "assist" can be affected by something as dumb as the PS belt tension. I've also panic stopped a hydroboosted GMC crew cab that was pulling an open trailer with a car on it. I dont ever want to be in that situation again. EVER. An evasive maneuver combining heavy steering effort and heavy braking effort is a bad deal.

Not a fan of vacuum cans, for the same reasons as already mentioned.

I have more than one car with manual brakes, and one of them is a disc/drum street car. With the right combination of parts, the pedal feel and feedback is hard to beat in my opinion.
To play devil's advocate here, the brake sizing on those mid 90's chevy light and medium duty trucks/suv's was piss poor. Hyrdoboost isn't necessarily the issue as much as the fact that GM put brake rotors and calipers on those vehicles that were originally on late 60's to early 70's cars that weighed 1500-2000 lbs less and weren't towing trailers.

Hydroboost is one part of the brake system, it can't make up for extremely undersized brakes with sheer line pressure.

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Old 02-24-2023, 02:31 PM
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When it comes to trucks, I've only had hydroboost on the 3/4 ton and 1 ton trucks we had. All of which have massive brakes on them.

My 79 1 ton had it, and up until the day I sold it a few years ago, the factory system was still working flawless. I owned that truck 25 years and never had a single issue with it.

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Old 02-24-2023, 05:14 PM
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Hydroboost is one part of the brake system, it can't make up for extremely undersized brakes with sheer line pressure.
No argument from me.

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  #6  
Old 02-24-2023, 05:49 PM
Schurkey Schurkey is offline
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To play devil's advocate here, the brake sizing on those mid 90's chevy light and medium duty trucks/suv's was piss poor. Hyrdoboost isn't necessarily the issue as much as the fact that GM put brake rotors and calipers on those vehicles that were originally on late 60's to early 70's cars that weighed 1500-2000 lbs less and weren't towing trailers.

Hydroboost is one part of the brake system, it can't make up for extremely undersized brakes with sheer line pressure.
The "big problems" with the GMT400 trucks were especially pronounced on the 1500 series; but those were by far the most-produced. There were enormously fewer 2500 and 3500 series trucks made compared to the 1500, and the heavier-series trucks also had much better brakes.

The 1500s had a crappy rear axle originally designed for compact and intermediate-sized cars. GM had no business putting it under a full-size pickup. That axle was almost universally equipped with 254mm (10") leading-trailing shoe drum brakes that require the park brake to be used in order to maintain shoe adjustment. Since nobody uses the park brake, the shoes are perpetually far from proper adjustment. Making things even worse, the front shoe on each side does all the forward braking. Which is why the front shoe will be worn-out long before the rear shoe--which does the majority of braking in reverse.

The first few years of that truck series, the regular-cab 1500s got a miniscule power booster, thin rotors, small-bore master cylinder, and tiny caliper pistons. Even GM acknowledged that the JN3 brakes were under-powered, in the early '90s they increased the braking power to JN/JB5 series brakes--what had come on the extended cab 1500s all along. But they still had the horse-crap leading/trailing shoe rears.

A rear-axle swap that replaces the junk 8.5" ring gear, 10-bolt axle with the 9.5" semi-floating 14-bolt cover axle also upgrades the rear brakes to proper 11.x Duo-Servo drum brakes where both shoes stop the vehicle.

Don't get me started on folks who think they can bleed ABS brakes on the post-1990 GMT400 trucks without using a scan tool to chatter the solenoids.

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