LSPV Replacement ? (1 Viewer)

[gabtrac]

Hi and thanks for having me. I hope I'm posting in the right place.
I have 94 Toyota 4x4 p/u with ABS and a leaky LSPV. I've seen guys replacing the LSPV with a Wilwood proportioning valve, but they don't have ABS. Can anyone tell me if replacing the LSPV with the Wilwood valve is the same procedure as without having ABS - plug the return from the LSPV? I also see guys removing the ABS, which I'd be happy to do, but I can't find any info for my 94. Much appreciated!

 

[pappy]

Hi and thanks for having me. I hope I'm posting in the right place.
I have 94 Toyota 4x4 p/u with ABS and a leaky LSPV. I've seen guys replacing the LSPV with a Wilwood proportioning valve, but they don't have ABS. Can anyone tell me if replacing the LSPV with the Wilwood valve is the same procedure as without having ABS - plug the return from the LSPV? I also see guys removing the ABS, which I'd be happy to do, but I can't find any info for my 94. Much appreciated!

Welcome to the group. As far as removal of the ABS, search the 80 series Land Cruiser forum. I suspect you will find directions over there, and the process would be the same.

 

[dohcdelsol93]

Lsvp and abs delete will get some safety police on you but we as a human species survived with fast vehicles long before abs was standard or even available. With a lift and big tires it's arguable that abs can be, at times, less safe.

With rear drums you want to install a 10 lbs residual valve along with the prop valve. Keeps the rear drum brake cylinders from leaking down and making the pedal all squishy. It's been a while so I can't remember if residual valve or prop valve comes first but this makes a difference, you'll need to search this.

If going to 4 wheel disks you don't need a residual valve, not in any yotas I've modified anyway.


At 1994 vintage id probably run all new brake lines so a good flare tool will be needed if you don't want leaky fittings. I've had great success reusing the actual fittings on new hose so long as they are not rusty or pitted. May want one of those tube bender pliers as well, when making tight bends it's easy to kink small brake lines.

Probably a good time to upgrade those brake lines to stainless braided while in there.

Good luck!

I daily drive my 87 with 4 wheels disks, 94 brake booster, Wildwood adjustable prop valve and gm 1 ton master. 94 v6 front calipers and rotors.

 

[gnob]

brakes work fine deleting both.
with big tires the lspv should be one of the the first deletes.
in fact, the early abs (rear only) and lspv are fighting to do essentially the same thing.
not only that the abs is based on the ring gear and not wheels. so not exactly awesome.

 

[dohcdelsol93]

I'm ditching all the slabs and abs on a disco 2 build. Post any information like that on a disco forum and they act like like I'm running over orphan baby dolphins while dragging manatee down the road by their flippers.

 

[gnob]

I'm ditching all the slabs and abs on a disco 2 build. Post any information like that on a disco forum and they act like like I'm running over orphan baby dolphins while dragging manatee down the road by their flippers.

i don't take mechanical opinions from rover drivers

 

[gabtrac]

Lsvp and abs delete will get some safety police on you but we as a human species survived with fast vehicles long before abs was standard or even available. With a lift and big tires it's arguable that abs can be, at times, less safe.

With rear drums you want to install a 10 lbs residual valve along with the prop valve. Keeps the rear drum brake cylinders from leaking down and making the pedal all squishy. It's been a while so I can't remember if residual valve or prop valve comes first but this makes a difference, you'll need to search this.

If going to 4 wheel disks you don't need a residual valve, not in any yotas I've modified anyway.


At 1994 vintage id probably run all new brake lines so a good flare tool will be needed if you don't want leaky fittings. I've had great success reusing the actual fittings on new hose so long as they are not rusty or pitted. May want one of those tube bender pliers as well, when making tight bends it's easy to kink small brake lines.

Probably a good time to upgrade those brake lines to stainless braided while in there.

Good luck!

I daily drive my 87 with 4 wheels disks, 94 brake booster, Wildwood adjustable prop valve and gm 1 ton master. 94 v6 front calipers and rotors.

Thanks for this, and yes I was planning to replace the lines. I haven't read anything about a "10 lbs residual valve" - what's that? And, do you know where I can get the directions to remove the ABS? Much appreciated.

 

[gabtrac]

Any recommendations on a good flaring kit?

 

[dohcdelsol93]

I'm not 100% sure of the layout of the 94 abs so this will be generic.

Take all lines and wires loose from ABS module. Remove module. Put in scrap metal.

Front brake master cylinder feed line now needs to feed the front brakes. You'll need a TEE to divide from drivers to passenger side. On the 87 there's a tee on a bracket that attaches to the two lower master cylinder studs.

Now the rear master line will feed the rear brakes.

There should the a tee already on your rear axle so not quite so much modification there.

There will be a return line triple tee that needs to be removed that used to be for your LSPV. This will be by the passenger tire on the frame (was on the 1st tr4 gen anyway). You'll now only need one like feeding from the master all the way to the rear axle.

To make things neat and clean I cut the triple TEE off and welded a regular TEE on it.

This, again, is very generic and may not be step by step what you'll encounter but it's similar to what I did on my 87 4 runner.


Brake residual valves can be purchased from whoever you get your Wildwood prop valve. Jegs, summit, etc. not sure id trust cheap china knock offs so reliable vendors should be a good bet. You just need one for the rear drums.

They make I think 2.5s for brake calipers but only used in applications where the brake calipers sit higher than the master cylinder i.e. race cars so not something you need to worry about in your application.

When you upgrade master cylinders make sure to purchase a non abs master. Not sure if there's a difference but on auto parts websites they list both with and w/o abs. The fj80 seems to be a poplar one for more fluid capac/flow

 

[dohcdelsol93]

Capri Tools 3/16 in. Double Flaring Tool (CP21110-316) https://a.co/d/2tpHSAs

This is the one I purchased for my 4 runner build. I've fought with the cheap ones from the local auto parts store for years and will never go back. I no longer have issues with leaky fittings

 

[pappy]

Thanks for this, and yes I was planning to replace the lines. I haven't read anything about a "10 lbs residual valve" - what's that? And, do you know where I can get the directions to remove the ABS? Much appreciated.

It's my understanding the residual valve is already built into the brake master.

 

[dohcdelsol93]

It's my understanding the residual valve is already built into the brake master.

This may be true of the yota master cylinders, so long as you're using one that was designed for disk/drums. In my builds I've went with GM master cylinders so I'm not 100% of the yota stuff.

If it were me, I'd install it without a R/V. Bleed the system with the prop valve wide open. See if the the pedal is squishy. If it's not I'd dial it in on a gravel/dirt road and see how it does once dialed in. If pedal is firm/responsive and my rear tires lock up right after the fronts, call it a day.

 

[ntsqd]

It's my understanding the residual valve is already built into the brake master.

This is the usual case, but I also don't have direct Toyota m/c experience. Typically they are under the sealing cone at the bottom of the outlet port. Removal of the cone is simple using either a sheet metal screw or a machine screw tap in the hole thru the cone. Delete the stuff behind the cone and then carefully re-install it.

Interesting that you have both ABS and an LSPV.

I have seen plugs made for inverted flare fittings. Can't recall if any of those were metric threads. If you can find a plug them can simply remove the tube to the LSPV from the T in the front brake circuit and plug it. Then an inverted flare coupler at the rear will by-pass the LSPV. Or you can put the adjustable p-valve there instead.

Merely pulling the main power fuse for the ABS unit will "remove" it from the system, at least in terms of it doing anything. Not being familiar with how Toyota plumbed their ABS units I've no advise on physical removal.