[How to] Remove the ABS from a ST185

darthripley

Moderator
Bryan - Whenever you're ready feel free to update, add more pics, add the wiring removal to the How To so we can get it as complete as possible.
 

toayoztan

Moderator
Will do!

As I will be making my own lines with the AGS NiCopp lines, I think adding to the existing write-up will make this a comprehensive How-To.

What sucks is I doubt Toyota carries the 3-way valve on hand...it's only 13 bucks, but I hate waiting a week for it to ship in. I may just pick one up from the junk yard...

Bryan
 

toayoztan

Moderator
I just wanted to give a heads up to you all for clarification.

The part number for the P-Valve on the ABS unit/brick is NOT the same as the non-ABS P-Valve located on the firewall.

The first 5 digits are the same, but actually looking up the part numbers and entering them into 1sttoyotaparts.com they come out to be different parts with two different prices.

I'm not sure what to conclude, but I can only be safe and assume these are not the same parts. Therefore, getting a non-ABS P-Valve, new or used, is going to be your best bet.

As stated, your other options are using the ABS P-Valve anyway, or going with an aftermarket piece like an adjustable Wilwood.

I am going to hopefully find a 3-way at the junkyard. If I can't find a non-ABS car, I'll just get an adjustable wilwood and a brand new OEM 3-way (they are cheap).

Here's a pic to illustrate.

proportioningvalvespart.png


Bryan
 

Meenya

New member
Here is what I did and it works:
There are 2 exits from master. Front top exit goes to a T which splits to front brakes.
Side exit goes to Wilwood adjustable and then to T (where P valve used to be) and splits to rear brakes.

I've tried to use non ABS P valve toyota but not celica and it didn't work.
So if you guys do go P valve route, you should get the Celica specific part.
 

toayoztan

Moderator
Meenya":3ig08djn said:
Here is what I did and it works:
There are 2 exits from master. Front top exit goes to a T which splits to front brakes.
Side exit goes to Wilwood adjustable and then to T (where P valve used to be) and splits to rear brakes.

I've tried to use non ABS P valve toyota but not celica and it didn't work.
So if you guys do go P valve route, you should get the Celica specific part.

I'm not sure exactly how it's all set up, or even what goes on in the pvalve. So correct me if I'm wrong!

The way the non-ABS is set up is that there appears to be two lines coming out of the master that feed INTO the pvalve. One of the lines, however, T's off to feed directly to the driver front brake without going through the pvalve.

At the pvalve, there are three other lines. One goes to the passenger front brake. The other two go to both rear brakes.

If we did the setup you did above, there are no issues with changing up the bias on anything regarding the front brakes?

I am not sure exactly what goes on in the pvalve, if there are just holes and tunnels, or actualy hardware with spring rates, etc. to adjust the bias of front/rear or even left/right (i know this sounds ridiculous, but never know i guess lol).

For the price of a new oem celica non-abs pvalve, I may as well get the wilwood.

Bryan
 

Meenya

New member
toayoztan":17fxs780 said:
Meenya":17fxs780 said:
Here is what I did and it works:
There are 2 exits from master. Front top exit goes to a T which splits to front brakes.
Side exit goes to Wilwood adjustable and then to T (where P valve used to be) and splits to rear brakes.

I've tried to use non ABS P valve toyota but not celica and it didn't work.
So if you guys do go P valve route, you should get the Celica specific part.

I'm not sure exactly how it's all set up, or even what goes on in the pvalve. So correct me if I'm wrong!

The way the non-ABS is set up is that there appears to be two lines coming out of the master that feed INTO the pvalve. One of the lines, however, T's off to feed directly to the driver front brake without going through the pvalve.

At the pvalve, there are three other lines. One goes to the passenger front brake. The other two go to both rear brakes.

If we did the setup you did above, there are no issues with changing up the bias on anything regarding the front brakes?

I am not sure exactly what goes on in the pvalve, if there are just holes and tunnels, or actualy hardware with spring rates, etc. to adjust the bias of front/rear or even left/right (i know this sounds ridiculous, but never know i guess lol).

For the price of a new oem celica non-abs pvalve, I may as well get the wilwood.

Bryan

Bryan,

If you or anyone else is removing ABS and will be upgrading the brakes, I think adjustable P valve is a good idea at least this is my opinion.
This is what I have Wilwood (260-8419) might be outdated part as I did it like 8 years ago. There is also Tilton which I believe a bit more expensive but they had metric version (makes it a bit easier) but it was on back order so I settled with wilwood.

As per your description, which is correct I have also attached a picture of the lines (unfortunately RHD so might be a bit confusing)
0b0a6b9d6e34281d7c16cb1e4f8d5488.png

In OEM set up as can be seen above there is a T adaptor fitting and P valve. In my set up there are 3 adaptor fittings. T adaptor (OEM), another T adaptor (Toyota) to split supply to rear brakes and adaptor fitting (Toyota) to connect OEM front lines that were connected through P valve before. So instead of 1 P valve as per OEM set up, I have 2 adaptors one is 3 way and one is 2 way.
The Wilwood P valve is inline before T adaptor which splits the rear right and left brakes adjusted to decrease pressure to rear brakes to avoid locking up of rear brakes before the front ones under hard or sudden braking.
The 2 way adaptor that connects 2 front lines could be eliminated from my set up by using the flexible brake lines you have asked for feedback on the forum, in other words you could create a line that would go directly to the 1st original T adaptor fitting by the master.

Hope that helps.
 

Smaay

Member
does anyone know if i can use the P valve and T from a 6th gen Celica ST? I have access to every part. will the lines work too if I tweak them a little bit?
 

underscore

Well-known member
Has anyone done this on a RHD car? Looking at the diagrams some of the stuff may be different for a RHD car.
 

Corey

Active member
I did. Purchased the necessary lines and valves from a RHD part out in the UK.

The tricky part wrt RHD is removing the master cylinder with the engine still in the car. Takes a wide assortment of sockets and wrenches, but it can be done.
 

underscore

Well-known member
I'm pulling the motor this winter so that shouldn't be an issue, were you able to keep any of the lines other than the ones running to the rear?
 

Corey

Active member
I think the engine bay lines all became redundant with the new proportioning valve and 3-way valve under the master cylinder.

Now just two lines run along the fire wall to the proportioning valve - one from the 3 way valve and one from the master.

The 3way valve also supplies a line to the front right wheel and a second to the master.

I think the front left wheel also has a new brake line to the proportioning valve.

diag_nonABS.jpg


Everything boxed in red is new.
 

underscore

Well-known member
Does anyone have a picture of the JDM three way valve? Why on earth Toyota used a different system for RHD and LHD I'll never understand. And does anyone know why the 88-91 and 92-93 proportioning valve are different?
 

mkernz22

New member
underscore":1kozmamm said:
And does anyone know why the 88-91 and 92-93 proportioning valve are different?

I don't believe they are, toyota just charged part numbers at that time for some reason. It took the guy at my local dealership 15 minutes to find me the correct timing belt for a gen2 engine cause two of the part numbers were discontinued...
 
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