80 Series brake hydro booster conversion installed

[baldilocks]

I bet everyone who buys Joey’s turbo kit would like this in a complete kit form. I know I would.

I’d suggest an OEM master cylinder for availability of roadside repairs.

As I said in the opening post, the stock MC won’t bolt up. And, one of the main features of this mod is the larger bore MC.

 

[baldilocks]

Sounded like some parts were sourced at NAPA, some via Amazon or eBay. It would be awesome for everything compiled, tested, & known to install without issue or additional parts sourcing.

The company I sourced my hydro boost kit from is already a known and proven resource. This is all he does and represents third generation of family ownership with tons of knowledge already compiled.

As for the odds and ends I listed, new pads and calipers were not parts needed to install a hydro booster. The only thing that was not direct bolt in were the hard lines that chose to make.

 

[NLXTACY]

Sounded like some parts were sourced at NAPA, some via Amazon or eBay. It would be awesome for everything compiled, tested, & known to install without issue or additional parts sourcing.

Tundra MC would have worked

 

[baldilocks]

What’s the bore diameter?

 

[synapse]

Good writeup. Nice to see someone do something like this. Seems like you need to do the ABS delete either prior to or at the time of doing this?

I've been trying to piece together a larger rotor and caliper kit and wanted to increase the MC bore diameter to make up for the slightly larger piston bores in the calipers I have in mind. Therefore pedal travel shouldn't be changed drastically.

From my very brief research, Tundra MC are <1.00"(13/16" and 15/16" from what I see) and would require more pedal travel for a given amount of brake effort.

 

[alia176]

Good writeup. Nice to see someone do something like this. Seems like you need to do the ABS delete either prior to or at the time of doing this?

I've been trying to piece together a larger rotor and caliper kit and wanted to increase the MC bore diameter to make up for the slightly larger piston bores in the calipers I have in mind. Therefore pedal travel shouldn't be changed drastically.

From my very brief research, Tundra MC are <1.00"(13/16" and 15/16" from what I see) and would require more pedal travel for a given amount of brake effort.

Can you please put things into perspective by telling us the bore diam of the 80 master cylinder?

 

[synapse]

Can you please put things into perspective by telling us the bore diam of the 80 master cylinder?

1" as mentioned in OP

 

[alia176]

D'oh. Thank you sir.

 

[baldilocks]

Good writeup. Nice to see someone do something like this. Seems like you need to do the ABS delete either prior to or at the time of doing this?

I've been trying to piece together a larger rotor and caliper kit and wanted to increase the MC bore diameter to make up for the slightly larger piston bores in the calipers I have in mind. Therefore pedal travel shouldn't be changed drastically.

From my very brief research, Tundra MC are <1.00"(13/16" and 15/16" from what I see) and would require more pedal travel for a given amount of brake effort.

Larger hardware at the wheel would definitely be more of an upgrade but the stock calipers should be enough unless you will be loaded up to or beyond max gvwr (includes a 5k lbs trailer) all the time.

Something not yet mentioned is that not every hydro booster is manufactured with the same boost power. I did hydro boost on a Dodge Ramcharger seven years ago with a kit that I bought from a different company and I can feel that the hydro booster I installed in my 80 isn’t as powerful as the one that I put on my Ramcharger and thankfully so because those brakes were too touchy even with 40” tires.

You could go to pick-n-pull and remove a booster from a one ton dually or an Astro Van or....... and have parts that might look similar but perform quite differently.

This is where the service offered by people who know hydro boosters and which one to match to which vehicle is worth paying for.

 

[jjdeneen918]

Good writeup. Nice to see someone do something like this. Seems like you need to do the ABS delete either prior to or at the time of doing this?

I've been trying to piece together a larger rotor and caliper kit and wanted to increase the MC bore diameter to make up for the slightly larger piston bores in the calipers I have in mind. Therefore pedal travel shouldn't be changed drastically.

From my very brief research, Tundra MC are <1.00"(13/16" and 15/16" from what I see) and would require more pedal travel for a given amount of brake effort.

Toyota T100 1-ton has a 1 1/16” MC bore.
That was the only one I could find that was larger than 1”.

Tundra MC’s just less than 1”. But maybe that is what would work best? Dunno?

 

[Jason Andrews]

I've run a couple different GM hydroboost units. I first one I ran back in 2009 was from a 1-ton GM truck/van which was 1-1/4" or 1.25" bore. Pedal travel was very short and I could easily push past it in an emergency situation. Just scary. IIRC I switched to a Camaro unit which is 1-1/8" or 1.125" like @baldilocks and thats what I've run since then. I believe I've seen people switch from 1.125" to a 1-1/16" or 1.0625" bore and made an improvement on that. That was on a FJ60 with 1-ton/14-bolt axles. That Wildwood is much nicer to look at than mine!

 

[baldilocks]

I've run a couple different GM hydroboost units. I first one I ran back in 2009 was from a 1-ton GM truck/van which was 1-1/4" or 1.25" bore. Pedal travel was very short and I could easily push past it in an emergency situation. Just scary. IIRC I switched to a Camaro unit which is 1-1/8" or 1.125" like @baldilocks and thats what I've run since then. I believe I've seen people switch from 1.125" to a 1-1/16" or 1.0625" bore and made an improvement on that. That was on a FJ60 with 1-ton/14-bolt axles. That Wildwood is much nicer to look at than mine!

Yes, the MC I used on the Ramcharger mention previously had a 1 5/16” bore and was a bit too much. I can see where perhaps a 1 1/16” bore would be a nice set up on an 80 if the preference is more pedal travel.

Again, booster power needs to be matched to the MC and this is where expertise is needed unless trial and error isn’t something a person minds going through on something like brakes.

 

[cruisermatt]

Tundra MC would have worked

The Tundra master cylinder doesn't look like it would bolt to the GM master cylinder? Does it?

Good writeup. Nice to see someone do something like this. Seems like you need to do the ABS delete either prior to or at the time of doing this?

I've been trying to piece together a larger rotor and caliper kit and wanted to increase the MC bore diameter to make up for the slightly larger piston bores in the calipers I have in mind. Therefore pedal travel shouldn't be changed drastically.

From my very brief research, Tundra MC are <1.00"(13/16" and 15/16" from what I see) and would require more pedal travel for a given amount of brake effort.

The beauty of the GM/domestic booster is it opens you up to a huge variety of master cylinder choices OEM and aftermarket.

 

[cruisermatt]

Something not yet mentioned is that not every hydro booster is manufactured with the same boost power. I did hydro boost on a Dodge Ramcharger seven years ago with a kit that I bought from a different company and I can feel that the hydro booster I installed in my 80 isn’t as powerful as the one that I put on my Ramcharger and thankfully so because those brakes were too touchy even with 40” tires.

You could go to pick-n-pull and remove a booster from a one ton dually or an Astro Van or....... and have parts that might look similar but perform quite differently.

Are you sure about this? I've been under the impression that all hydroboosts are the same. It could be that whatever domestic power steering pump was on your Dodge was more powerful then the 1FZ pump which would make the hydroboost more effective. No one has said a word about the 1FZ pump yet.

 

[alia176]

I'm enjoying the education, thank you gents.

 

[baldilocks]

Are you sure about this? I've been under the impression that all hydroboosts are the same. It could be that whatever domestic power steering pump was on your Dodge was more powerful then the 1FZ pump which would make the hydroboost more effective. No one has said a word about the 1FZ pump yet.

I based my statement on info I have gathered from the internet. I know that a lighter vehicle such as an Astro Van wouldn’t require the booster power that a 1 ton truck would so it makes sense that hydro boosters would come out with different boost ratings.

The pump I was running on my Ramcharger was a pump I got from PSC as part of a hydro assist steering upgrade. They refered to the pump as “high volume”. Probably to keep up with the ram.

The 80 stock pump puts out something like 1400-1500 psi. I do know that with 37’s, I have little to complain about when in the rocks which is more than I can say for other stock power steering systems I have run.

If I ever do hydro assist on my 80, it would be mostly to lighten the load in the frame and track bar brackets.

 

[baldilocks]

Can you please put things into perspective by telling us the bore diam of the 80 master cylinder?

I removed the guts from my old Aisin MC and took a measurement of the bore with a caliper. I came up with 63/64”.

 

[synapse]

Toyota T100 1-ton has a 1 1/16” MC bore.
That was the only one I could find that was larger than 1”.

Tundra MC’s just less than 1”. But maybe that is what would work best? Dunno?

Best will be relative to exact setup and preference. I'm intending to eventually go aftermarket calipers that have slightly larger piston area. If I keep MC bore the same this will cause more pedal travel for the same amount pressure at the brake discs. Some may like the extra travel for finer modulation.

Not taking into consideration any brake booster, think of the piston area of the calipers to the piston bore of the master cylinder as a ratio. Increase the piston area of the calipers, the master cylinder piston needs to move more fluid and requires more pedal travel. This will also create the sensation of a less firm pedal. Do the opposite and increase the piston bore of the MC, while keeping the piston area of the calipers the same, and the MC is more efficient at pushing fluid so less pedal travel is required, and creates the sensation of a firmer pedal.

 

[cruisermatt]

It should also be noted that users should be weary of installing hydroboost on a vehicle that doesn't have a properly functioning or well thought-out brake system, as it can give the impression that the system is working properly since it gives a very firm pedal feel just by the nature of its design.

 

[baldilocks]

It should also be noted that users should be weary of installing hydroboost on a vehicle that doesn't have a properly functioning or thought-out brake system, as it can give the impression that the system is working properly since it gives a very firm pedal feel just by the nature of its design.

Please elaborate on this.