brake booster conversion

[firemedicsafd]

I want to convert from vacuum booster to hydraulic booster on my brakes for my 82/88 k5. I have a few questions related to it before i pull the trigger.

Will i have to change master cylinders?

Will i have to change brake pedal assembly?

I am in the process of converting to 1 ton axles. Will i need to change line size or proportioning valve?

The rear axle will eventually see a disc brake conversion. Will i have to adapt anything to make that work correctly?

does the conversion to hydraulic brakes interfere with big tire steering?

thank you all for your help!

 

[dremu]

I want to convert from vacuum booster to hydraulic booster on my brakes for my 82/88 k5. I have a few questions related to it before i pull the trigger.

Will i have to change master cylinders?

Will i have to change brake pedal assembly?

I am in the process of converting to 1 ton axles. Will i need to change line size or proportioning valve?

The rear axle will eventually see a disc brake conversion. Will i have to adapt anything to make that work correctly?

does the conversion to hydraulic brakes interfere with big tire steering?

thank you all for your help!

The master cylinder is different from vacuum to hydroboost, yes.

The pushrod to the booster mounts to a different hole on the brake pedal. I gather that later pedal have both holes; mine did not, so I swapped pedals. It was a bolt-up affair.

I would not change the combo (prop) valve, even to do disc.

-- A

 

[Massacre-77]

ckeck this out http://www.hydratechbraking.com/GM_73-79_CK.html

 

[sweetk30]

as said master is diffrent bore size of the body to the hydro boost. lines same size.

pedel is diffrent and hole in diffrent spot and pin dia also diffrent.

same prob valve dont need to swap.

other wise if me get what you can from doner vehicle you you got it all in the end.

also dont forget the p/s pump will be 3 hose for the hydro boost unit return.

 

[78 Bonanza]

Brakes

If you go with the disc brake setup on the rear you will need to delete the prop. valve and install an adjustable brake control. If you don't you are going to have problems. Some people do it and can live with the fading and uneven braking but to do it right you need a manual adjuster inside the cab to set it up right.

 

[Tnsejed]

Depending on the unit used if you can snag the pedal assembly from the donor vehicle you can take your stroke measurements from the original pedal assembly. Then just drill out your K5 assembly and add a pedal stop if needed.

For example I used a 1996 hydroboost and master out of a G30 van. Stroke was nearly identical to my vac pedal assembly in my 89 blazer once I adjusted pin height. I also ran my hydroboost unit upside down as the van mounting plates are angled to match the van firewalls. This arrangement gave me a good range of movement for the rod. You need to make sure the rod does not bind anywhere during full stroke.

 

[MrSchaeferPants]

...
also dont forget the p/s pump will be 3 hose for the hydro boost unit return.

I'm not sure why, and that threw me for a loop when I got my 84 CUCV. Only other vehicles I worked on with hydroboosts were HMMWVs, and they only had a high pressure and one return on the power steering pumps. It was high pressure out of the pump to the hydroboost, high pressure out to the gear box, and return to the pump, there wasn't a return on the hydroboost.