Wondering if anyone has heard of this. Off of an ITR. Could this proportioning valve be a little biased towards the rear?

 

you are probobly thinking of a 40/30 prop valve
never heard of 30/40

 

nope 3040 is whats stamped on it. Pulled it right off of an ITR clip.

 

well if you send it to me i'll try it out and see what happens.

thanks. haha.

you should post up pics. i've never heard of a 3040 either

 

I have one too but cant get the breaks in because the bearings are shot.
put it in and see how it acts.

 

I believe it's off an EH3.

 

Hi Elmer. Never heard of a 3040. What car do you drive now?

-Byron

 

I saw a 3040 on a EG sedan

 

Just get the proven 40/40 one!

 

I have seen a 40-30 on a rhd eg6. Assuming it was stock.

There was a 30-40 on my '92 si. Stock. The ones with the small front brakes.


Modified by _BEN_ at 5:10 PM 10/3/2005

 

30-40 on an Si makes sense. maybe the guy who "pulled" it off an itr really didn't LOL. oh well... brake bias doesn't feel bad... and if it's biased towards the rear it's def not a problem the way i drive. nose isn't diving nor is the rear squatting in a straight line and feels good when trail braking. brake setup is a 99 gsr booster and 1" master cylinder, integra 4 wheel disc, brembo blanks, oem nissin pads and some goodridge lines.

whats up byron... working on a 93 VX right now... nice to be back in the game with a full project.

 

Why the hell would there be a 30/40.

99% of the work is done by the front brakes. The rear brakes just stabilize

 

The proportioning valve for drum brakes allows the pressure to equalize before pressure is applied to all 4 wheels. When you have a caliper in the rear instead of a wheel cylinder then the pressure is not alleviated by a return spring on the drum brake pads. This means that no gap is lost from the pads and friction surface therefore there will not be a need for pressure equalization. Your stock prop. valve is an automatic unit and will be able to differentiate the difference and will have no adverse effect on braking. There will be no lag in rear brake application like the rumors and misinformed indivuals will tell you.

There are tons of people in Honda Challenge racing with stock drum prop valves racing with 4 wheel disc. If the prop valve adversely effected the vehicle, none of them would even touch the stock unit, except to remove it.

 

really?

So there is no benefit in having a 40/40 prop. valve when doing a rear disc conversion?

 

the #'s are purely part #'s, not force distribution. i had a 3040 off a DA teg on my EG hatch. worked fine with my 4 wheel teg brakes.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by dantastic &raquo;</TD></TR><TR><TD CLASS="quote">the #'s are purely part #'s, not force distribution. i had a 3040 off a DA teg on my EG hatch. worked fine with my 4 wheel teg brakes.</TD></TR></TABLE>

i dont think they are part numbers.

the 40/30 gives more pressure to the front because you need more fluid to move the larger piston, and less to move the smaller rear wheel cylinder in drums,
the 40/40 gives more pressure to the rear.

but it is very true that the brake ratio is like 70/30 on a car. 70% of work done by the fronts and 30% by the rears

 

Someone told me exactly what DirtySol is talking about. Thanks DirtySol for the very thourough information.

if you account for different size master cylinders and what DirtySol is talking about, prop valves do not effect how much pressure goes to each caliper/wheel cylinder... interesting.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by built562 &raquo;</TD></TR><TR><TD CLASS="quote">

i dont think they are part numbers.

the 40/30 gives more pressure to the front because you need more fluid to move the larger piston, and less to move the smaller rear wheel cylinder in drums,
the 40/40 gives more pressure to the rear.

but it is very true that the brake ratio is like 70/30 on a car. 70% of work done by the fronts and 30% by the rears</TD></TR></TABLE>

the proportioning valve has nothing to do with pressure distribution.......in a hydraulic system all pressures equalize over time. The proportioning valve is designed to allow a quicker pedal response for drum brake vehicles by allowing the rear brakes to get the brunt of the fluid first to allow for the pads to make contact. As soon as there is resistance then the pressure through out the system equalizes immediately. Therefore, if you have very little to no gap (like every disc brake on a Honda) then you will have no deviation in pressures between the front and rear brake fluid distribution.

The prop. valve acts as an automatic orifice tube that senses pressure equalization. Once pressure throught the system is qualized then the porp. valve is nothing but a brake fluid passage.......that is it.

Do not confuse a Proportioning valve with a brake control metering valve. The metering valve (kinda like Wilwood's adjustable unit) is nothing but a controlled orifice that is not allowed to alleviate after pressure is equalized.

 

Sorry but just to clarify.

The 40/40 prop. valve is ABSOLUTELY not needed in a rear disc swap? there is no benefit whatsoever?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by _gurusan_ &raquo;</TD></TR><TR><TD CLASS="quote">Sorry but just to clarify.

The 40/40 prop. valve is ABSOLUTELY not needed in a rear disc swap? there is no benefit whatsoever?</TD></TR></TABLE>

correct........besides the fact that you can say that you have one

the only reason that Honda has a different unit on the cars with 4 wheel disc is becasue the cars do not need the control valve for drum brake application and the valve would have internal parts that are not even needed for proper brake application (for reasons explained above) so to save on cost they changed the unit to a simpler, more cost effective unit.

 

You saved me 25-45 bucks!


props to you buddy!

This info should be stickied!