Hi,
My 105 with the 1750/2000 brakes needs a new set of pads (front and rear)... something with good to great performance for the road (spirited driving) and the track (for the real fun).
I was wondering if anyone has opinions on the Ferodo DS2500's and sources for them in Aus?
Cheers,
AP
2500 are good but 3000 have better performance from my experience (seem to have a better initial bite). they are expensive but the last along time, I got to targa's 4 six hours and a lot of sprints in between from 1 set! so I think they're pretty good value for money. Was never to concerned about street performance, but never had an issue with cold pads on transport stages.
Thanks for that I have ordered the DS3000 pads.....
Let's see if it stops now!
With the pads and the Alfaholics twin mc setup it should work....
AP
Are you happy with Alfaholics twin MC setup? i would be very interested to know how much compliance you find with that setup
Colin,
The unit is well made and I am very happy with it so far, once th DS 3000's arrive it should stop a lot better.
Not quite sure what you mean by compliance...
I am currently running the std ATE calipers off a 1750, the balance bar is almost out of travel set with 2-3mm of bar left for more front bias, this is with the two mc's supplied. So if I ever want bigger front calipers it should be ok without changing the mc sizes.
Here is a view of the mc's at work:
http://i262.photobucket.com/albums/ii118/apfubar/Alfa%20105/ae6c267d.mp4
FYI during the install I had to do a bit of floor pan adjustment to get the box in, as my floor dipped away from the chassis(or the chassis wasn't vertical). Nothing a couple of taps with an adjusting stick(rubber mallet) couldn't fix.
Cheers,
Andrew P
Curious to know what size masters the Alfaholics box comes with...
I've been very happy with my ds2500s.
Ferodo recommend DS3000 front and DS2500 rear. I have used this on all my track cars. This is the best combination for rear wheel drive. Slightly less friction at the rear. (Tried and tested on 1750 GTV, Alfetta GTV,Datsun 240z,Fiat Arbarth,Fiat 125)
If you wish purchase from USA for half the cost here.
QuoteNot quite sure what you mean by compliance...
I was just wondering if there was much movement in the master cylinder box when apply pressure to the brake pedal. I ask as I built a similar style MC box for my car and initially had issues with the very thin gauge chassis rail flexing. From all the photos of the alfaholics box it should be worse as the spacing of their MC is further apart so there will be a larger moment applied to the chassis rail. I've since strengthened my chassis rail and added a small arm back to a floor cross bar. It is amazing how much even the smallest amount of movement in a the mechanical part of the braking system will be felt by the driver.
QuoteThis is the best combination for rear wheel drive.
Whilst this may be true for many vehicles, i'd be careful making blanket statements like this, there are many factors that determine the correct brake bias for a car and friction coefficient of the brake pads is only 1
Ben, afaik the ah twin mc box doesn't come with any.
I'd be very keen to see how this turns out as I am looking to go with the twin mc kit myself with no boosters. The idea of some f r bias control (through twin mc's) and the peace of mind with a dual circuit setup appeals to me over the single mc/booster. I already have the AH billet brake kit front and rear, just need to finalise out the other half of the system.
Colin, your chassis flex comments are also making me think a little more about chassis re-enforcement in that area. Do you have any pictures you can post?
sorry it took so long, car has been away getting the engine bay re-sprayed,
Interesting re the chassis flex...
Just thinking that the Alfaholics unit mounts hard up to the rail over a reasonable are, which may eliminate the chassis flex issue...
When I get the car up on the ramps again I will check that...
When the motor comes out for the clutch replacement and rear main I will put a brace in if it does flex, I already have to brace the steering box so another bracket or two won't be a problem.
BTW off to "driver training" at Wakefield Park in a couple of weeks so it will be interesting to how the brake system holds up...
Cheers,
Ap
So Andrew after another 2 months of use ?? - your overall consensus on the AH twin mc brake setup is that it is exceptional / good / acceptable?
From the video you have posted (http://i262.photobucket.com/albums/ii118/apfubar/Alfa%20105/ae6c267d.mp4) there is a lot of play in that mechanism - was that when it was in the car and installed ? Can you see any inherent faults with the setup ?
QuoteJust thinking that the Alfaholics unit mounts hard up to the rail over a reasonable are, which may eliminate the chassis flex issue..
.
My pedal box also has a large u bracket (5mm) that clasps on to both sides of the rail that is relatively long and the rail was still flexing, so I'm tipping there will still be flex in the system.
QuoteWhen the motor comes out for the clutch replacement and rear main I will put a brace in if it does flex, I already have to brace the steering box so another bracket or two won't be a problem.
I've just been through this so I'd be very interested to know what type of brace are you planning for the steering box ?
Quotethere is a lot of play in that mechanism
you'll should always have a little play in the linkage system to the MC of a hydrallic system otherwise you can run into the problem of a constantly pressurised system. You can also run into the problem of not allowing the MC piston to retract enough to re-open the gallery to the fluid reservoir.
Quote from: pancho on July 20, 2011, 09:37:26 AM
So Andrew after another 2 months of use ?? - your overall consensus on the AH twin mc brake setup is that it is exceptional / good / acceptable?
From the video you have posted (http://i262.photobucket.com/albums/ii118/apfubar/Alfa%20105/ae6c267d.mp4) there is a lot of play in that mechanism - was that when it was in the car and installed ? Can you see any inherent faults with the setup ?
The system is good... It is well engineered and meets my needs. It makes the conversion to a twin circuit setup easy, and allows for adjustment of the front to rear bias, moves to STD master cylinders(cheap and easy to refurb or replace), and the mc's should last longer as they are protected from the weather by a cover plate. The only reason I can't yet rate it as excellent is the possible flex issues. Once I check that out I will know if there is more work to do and feedback to Max any points of concern...
FWIW Please be aware that the car has covered about 1,000ks since the install, on public roads. The pedal pressure is still a concern, but that is only due to the lack of vacuum assistance... and me being slack and not changing the rear pads yet...
Cheers,
An update based upon the weekend's fun:
- installed the soft rear pads
- checked the mc mounting for flex - just noticeable (by looking at the end of the mc) movement, max 0.5mm under full pressure
- adjusted the brake balance
After driving at Wakefield, the brake pedal pressure is still a big challenge... Both of us drivers started to tire at the end of each 15 mins section.
Then again the shoulders and arms are sore from hustling the Alfa around so I am not sure how much more time I would want to spend driving it at ten tenths.
On the chassis strengthening for the steering box, not sure how I will progress on that one... It's down the priority list, behind the clutch and brakes...
Cheers,
AP
Well after reviewing the video footage, the brakes definitely require more thought and modifications to reduce the pedal pressure... Then I will look into the other problems...
Given the DS3000's are already on the car... Softer pads aren't an option....
Options to reduce pedal pressure:
1. Install a booster or two...
Need to source one, stick it in the front circuit.... Doesn't need to be an original (little of the accessories are original), just reliable, cheap and easy to source....
2. Reduce M/C size
Not sure if this is possible need to check the current sizes...
3. Bigger front brakes (piston area)
Are the 75's brakes bigger?
Are ther other 'reasonable' options....
I don't have a rear pressure limiting valve in at the moment, but I don't think that would alter the pedal pressure...
It is stopping straight and all 4 brakes are hot but none are stinky so, I know they are working pretty well.
Hmmm..
Other thoughts?
Ap
Looks like you have covered most of the options for changing pedal force. But I'll just make a quick comment of each one as I see it.
Starting at the wheel end of the system
1. Brake effective radius - very hard to change means new rotors, calipers/mounts
2. Pad friction level – The DS 3000 have a relatively high mue so you've probably done all you can here, I was a bit confused by your comment about "softer" pads not being an option. Are you talking about compressibility?, if you are you want the stiffest pads you can get to reduce pedal pressure
3. Caliper piston size – New calipers, Can you fit the Volvo Calipers in?
4. Master cylinder size – I've just been through this to change my Front/Rear bias. I went to a tilton MC as they have a lot of different size options. I'm sure Girling MC come in a range of sizes, so this is probably a good option
5. Pedal Ratio – Not sure if there is space to do something here but if there is this could be a very simple fix. If you are able to shift the clevis of the push rod up the brake pedal closer towards the pivot point you'll end up with a higher pedal ratio and less pedal force to get to locking pressure. I actually designed an extra pivot arm into my system so that I could easily change this ratio and it works very well
QuoteI don't have a rear pressure limiting valve in at the moment, but I don't think that would alter the pedal pressure..
Your correct it won't and I wouldn't recommend putting one in after you've gone to all the trouble of adding a proper twin MC setup. I've had problems in the past with pressure limiting valves working in both directions, i.e rear brakes staying engaged without pedal pressure.
Hope that helps, it's worth spending the time to get a good system
Good luck