volvo 240 brake system

Quote
a1only
This thread didn't go well. I was hoping for acutual information, not a pissing match about brake pads and left foot braking. John, I don't rally and I don't have a "hydro" hand brake. Thank you to Robert for an actual reply. I was warned about this forum, now I know why, have fun guys, it's been real.

Mike Sam

If this is what you consider a pissing match, and if "Robert Culberstons " second hand opinions in what you consider about some junk road car pads "an actual reply' then maybe what I was warned about
"track day" guys is true..


Is it true they're all, well, you know....like that?
If not, why do they simper and whine like they do?

Just note: the RX7 brake set up was invented right here about 35 feet over <-----that direction way back in maybe 02....
It was soon deemed inadequate---nice and trick looking but a serious reduction in piston sizes meant an 11% reduction in piston area.....better than some kits from Canada which reduced piston area by 18-19%
Not the ideal direction, at least for an upgrade..

---

John Vanlandingham
Sleezattle, WA, USA

Vive le Prole-le-ralliat

www.rallyrace.net/jvab
CALL +1 206 431-9696
Remember! Pacific Standard Time
is 3 hours behind Eastern Standard Time.

John. I came to this forum from TB do to a lack of real motosport experienced users. I'm aware that you came up with the RX7 swap. That's the reason I came here for insight. I should have been more forthcoming. I don't have a great grasp on the 240's diagonal system. I'd like to install an adjustable brake bias and do away with the stock system except for the master cyl and rear calipers. I decided on the RX7 calipers because of better pad availability and the fact they fit under small wheels. I run 15" wheels in an attempt to reduce my tire costs. Going back to a stock is a possibility if that's the cure. Could the unpredictability be due to the two proportioning valves and the brake junction. Should I gut the brake junction.

Mike Sam

Not sure why my name is in quotation marks. Maybe I should get an alias that's the same as my real name. Or maybe I'll switch it to "Rufus Pendleton"...
Anyways, back towards Volvo brakes.
Turbobricks might be the better spot to ask questions without a thread getting derailed. At least the moderators there will remove posts that are completely off topic. There's also a few people that road race their bricks over there. There are about 5 active rally bricks in the entire country right now (that's not a whole lot).
The junction block is not some mystery, it's a simple device that lets the driver know that there is a failure in the brake system. There is a pretty good thread on TB that just recently talked about a rear proportioning valve in the 240, modifying the brake system slightly.
What is your mechanical ability and access to tools? Brake line flaring tools? Adapter fittings? Removing the limiting valves and adding your own is pretty simple, it just takes some time, tools, and fittings to get right.
The stock brakes work very well with ducting for road course use, off the shelf pad selection is poor.

Think about your suspension, if a wheel has poor traction in a certain situation, braking will be funky.

Personally, I'd go with a stock brake set up, nice fresh rotors and pad, bleed the lines with nice high quality fluid right before your event, and keep things simple. I have always felt the stock 240 brakes worked very well. Also maybe get coached on proper braking technique by a pro, its an art.

If you are going to custom it out, the front calipers from abs equiped 240 has just one line running to it, so you can do a cleaner set up with out goofy dual lines getting spliced together.

Robert. I've decided to install an ABS master ( which has separate front and rear circuits) and add a tilton adjustable limiter mounted in the cabin to adjust rear brake pressure. My confusion is that the non-ABS master applies pressure to diagonal corners, did this fact have an effect on trail braking? I've noticed that I'm locking the inside rear tire only during turn in, straight line hard braking is fine. Is this attributed to the diagonal system? I can "can drive around" the trail braking issue, but it seems to tuck the front end in nicely when I'd do.

Regarding TB, it's been a great resource, truthfully I'm 47 years old, it seems a bit juvenile at times. Thanks for taking the time to respond.

Mike Sam

Quote
a1only
This thread didn't go well.

By Rally Anarchy standards I'd say it was going extremely well.

Quote
a1only
I was hoping for acutual information, not a pissing match

And you got real information, with a bonus pissing match thrown in.

Understand that Rally Anarchy is like a box of chocolates. You never know what you're going to get from a thread until you open it up.

...and THAT is why the sport is sometimes called Forrest Racing.

Quote
ALS FTW
And you got real information, with a bonus pissing match thrown in.

Understand that Rally Anarchy is like a box of chocolates. You never know what you're going to get from a thread until you open it up.

...and THAT is why the sport is sometimes called Forrest Racing.
Reply Quote Report

Ok this place is dysfunctional. I'm going back into the shop until I come up with a solution

Mike Sam

Quote
a1only
Robert. I've decided to install an ABS master ( which has separate front and rear circuits) and add a tilton adjustable limiter mounted in the cabin to adjust rear brake pressure. My confusion is that the non-ABS master applies pressure to diagonal corners, did this fact have an effect on trail braking? I've noticed that I'm locking the inside rear tire only during turn in, straight line hard braking is fine. Is this attributed to the diagonal system? I can "can drive around" the trail braking issue, but it seems to tuck the front end in nicely when I'd do.

Mike Sam

Mike, the MC is not what separates the front and rear circuits, the brake junction block does.
Dave Barton has a nice page on the different ways of redoing the brake system: http://www.davebarton.com/volvo240bigbrakes.html

When adding a rear proportioning valve, you will either need 2, or Tee the lines together before and split them afterwards. If you tee them together, make sure you get the hoses correct at the junction block (if you choose to retain it) or you may loose all brakes if you spring a leak.

My turbo 242 will trail-brake very nicely (tail wag if desired) if I'm on the bakes hard deep into a corner. It's a completely stock non-ABS system with fresh fluid and decent pads. Locking the inside rear on turn-in while trail braking is a very common trait. That's the tire with the least amount of vertical load on it, so it should lock up first
Hard braking and turning in should unweight the inside rear tire, causing the lockup. That could be completely normal... Unless it's happening at mundane driving speeds.



Edited 1 time(s). Last edit at 06/17/2015 09:08PM by Robert Culbertson.

Quote
a1only

Quote
ALS FTW
And you got real information, with a bonus pissing match thrown in.

Understand that Rally Anarchy is like a box of chocolates. You never know what you're going to get from a thread until you open it up.

...and THAT is why the sport is sometimes called Forrest Racing.
Reply Quote Report

Ok this place is dysfunctional. I'm going back into the shop until I come up with a solution

Mike Sam

Not dysfunctional at all. Your exact question has been answered here with diagrams and text and photos dozens of times.
What we can't do is convince people that 90% of the time they're over-thinking and over worrying thing resolve 35-40 years ago and that they should just do what has been long established: simplest possible set up...

And then there's ideal and ideal CHEAP...

The cheap solution for calipers you've tried..I eventually decided---along with the car owner---that the front brakes UNASSISTED for simply not strong enough...

The do an improvement would mean actually buying something...



That is a $30.80 rebuilt ABS caliper---one hose in..

Skip all the OEM junction/limiter/proportioning BS
-------= hard line
Fronts:
Outlet from master-----> mount----hose----> caliper

Rear:
Outlet of Master-------->Limiter $39.99----------->"parking brake------------------------ T $1.39-----bulkhead fitting

$8----Hose------out to calipers.

---

John Vanlandingham
Sleezattle, WA, USA

Vive le Prole-le-ralliat

www.rallyrace.net/jvab
CALL +1 206 431-9696
Remember! Pacific Standard Time
is 3 hours behind Eastern Standard Time.

i need clarification on this!

grab a set of 740 ABS calipers. like NUGEON Part# 2209310L and 2209310R ???

these bolt on with no modification?

Quote
Paul Buck
i need clarification on this!

grab a set of 740 ABS calipers. like NUGEON Part# 2209310L and 2209310R ???

these bolt on with no modification?

No 240 ABS calipers
Rock-otter
NASTRA Part # 122247
Reman; Semi-Loaded
Front Left; Girling; ------->Single Inlet (Only 2 Remaining)<----------

Part Image
$36.79 $37.00 CORE! $73.79
NASTRA Part # 122246
Reman; Semi-Loaded
Front Right; Girling; -------------->Single Inlet (Only 6 Remaining)<--------------

Part Image
$36.79 $37.00 CORE! $73.79

---

John Vanlandingham
Sleezattle, WA, USA

Vive le Prole-le-ralliat

www.rallyrace.net/jvab
CALL +1 206 431-9696
Remember! Pacific Standard Time
is 3 hours behind Eastern Standard Time.



Edited 1 time(s). Last edit at 06/21/2015 04:34PM by john vanlandingham.

got it. thank you john.

ok, so please pardon my immense stupidity and hijacking this thread. this is my first big brake overhaul and i want to get as much info and clarification as possible.

so i'm going to basically do what john mentioned above here. i got the abs calipers, new hoses, and proportioning valve and now just need to hodge it all together.

am i going to need a bubble flaring tool? it almost looks like with some creative and careful bending i can use the existant hard lines, but knowing my luck i'll need it and not have it.

after the prop valve i need a t junction, something like earl's part number 972057b which is a jegs pn 361-972057b. it's a 3an in to two m10 x 1 bubble flares. i know john showed a 3an to 3an t junction, but as i said before, i am ignorant in brakes.

anything else i'm missing?

Skip bubble and go AN flares, 37° flares. The tools are spendy... but I have one that you are more than welcome to use in the next few weeks.
AN fittings and JIC (common hydraulic) fittings are the same. Cheap at any hose shop.

Give me a call if you need the flaring tool or want to see another Volvo with custom lines and a hydro-handbrake for inspirational purposes.

the only reason i was thinking bubble was because i was going to use as much of the hardline and fittings as i could. but i probably should just go all new line and more common fittings...