Alfa Pages

[Bobkelso]

Hi,
actually I'm using daily more a little car than my 33
because more comfortable when I'm in the traffic.

So thinking if it is possible to make some upgrade on the 33.
I already have power steering, and I have modified the
sitting position, changed the seats, moved nearer
steering wheel and gear lever, all useful but
now I'd like make brake pedal light as recent cars.

Before messing with upgraded discs and caliper
(I have only 14 diameter wheels) I'd like change the brake booster.
Actually on 33 there is one 8 inch large (inner effective is 7 inch)
that is a very weak help for the mass of the car (may be was right
for first alfasud 820 kg), and there is no space for bigger diameter.
Alfa 33 brake booster is 205mm diameter and 100mm long, and
brake pump is another 160mm long, and very little more space
is still available in the car (may be another 20 mm).

So I was searching for a 8 inch (7 inner) brake booster (200-210mm) but the
"double" ("tandem") type that almost double the brake assistance.
Actually I founded possible compatibility with old tandem type 8 inch
from Bendix (mounted on many volvo, as 240 or older version of
740-760 models, or on older Iveco Daily light truck, sometime
available for 200e or less on ebay) but not sure if they are
8 inch external diameter or inner diameter (in that case they are 9 external)

http://www.ebay.com/itm/261085626089?item=261085626089&pt=Motors_Car_Truck_Parts_Accessories&cmd=ViewItem&hash=item3cc9ea7ee9&vxp=mtr

but I have to find a shorter brake pump compatible because
the tandem type booster is 50-70 cm longer than original and
there in not enough space in the car for the original pump.

Was thinking also to study directly a recent complete system from Bosh
(8 inch tandem booster + modern short brake pump, choising the pump
with 20mm inner diameter like the one of 33, it is posissible in modern
bosh system as all pump and booster are modular and compatible)
..but no catalogue founded on internet.

Somebody have some suggestion on what recent car I can study
to find a bosh tandem booster 8 inch small diameter or similar?
(I think it can be founded in small cars that have some technical
space limitation in the bonnet, because for example recent Golf
have bigger (11 inch) tandem booster)..
_________________
Alfa 33

[BigAl]

Have you thought of trying the alfa 75 master cylinder as an upgrade first?
_________________
x2 33 16v
pictures http://www.alfa-pages.co.uk/viewtopic.php?t=5203

[Bobkelso]

Hi, what I know about is:
alfa 75 system is bendix and compatible with 33,
(edit: the drum booster is larger, 8 inch internal diameter,
9 inch external diameter)

- some rare alfa 75 with bigger motors have an upgraded
tandem booster but rare to find and I'm not sure
if is 8 inch or 9 inch external diameter..

- 75 brake pump is 100% compatible with 33
and with older Iveco Daily ligh truck, and
available with inner diameter from 20 to 24 mm,
but all diameter bigger than 20mm (the one 33 use)
used with standard 33 calipers will make the pedal brake
heavier to use, and from the images I founded
it seams that also the 75 pump are 160mm long
(it seams is the same construction of the one of 33)..

- may be I can adapt lancia y /fiat punto model 1996
brake pump (is quite short and 20mm inner diameter)
but still not sure it is compatible with the old type
bendix tandem booster, as the booster on that car
is Bosh (unfortunately is single type 9 inch, it is better
than the one on the 33 but it is too much large to fit),
so I'm still not buying all the stuff..

Any suggestion will be appreciated..

[BigAl]

I thought the 75 master cylinder would make the pedal easier as it moves more fluid.
I think Alex did the conversion, i'll get him to post
_________________
x2 33 16v
pictures http://www.alfa-pages.co.uk/viewtopic.php?t=5203

[Bobkelso]

Hi Al,
for what I concluded, bigger master cylinder can
be useful if you use upgraded calipers, for example
is you go from original front disk calipers with piston
of 48 mm diameter (both 8v and 16v alfa 33 calipers)
to some other calipers with bigger piston diameter
(52 mm like older opel astra/vaxaul or 54 mm like
alfa 145 calipers) to conserve short pedal travel
and good pedal feeling (not like "rubber" response)..

Instead for have lighter force on the pedal you can:

- reduce the diameter of the inner piston of the pump
(but with the just said problems, long pedal travel
and better feeling, or worse you could have not
enough liquid moved to operate correctly the calipers)

- use bigger disks than 239mm original ones (this is good also
for have better resistance to temperature fading) or/and calipers
with bigger pistons;
here some images of one user of an italy forum who opted for
radical 284 mm big disk and 15 rims and may be used a 22mm alfa
75 pump to move enough liquid to operate the hudge calipers

http://forum.clubalfa.it/alfa-33/4962-alfa-33-1-7-16v-rosso-alfa-e-bianca-1990-co-4.html
and
http://forum.clubalfa.it/alfa-33/4962-alfa-33-1-7-16v-rosso-alfa-e-bianca-1990-co-5.html

After reading post from other people, one option for me, as I have
original 14 alloy rims, would be to adapt 257 mm disk and 54mm calipers
from earlier alfa 145 8v boxer, they are not vented disk (so not to much
heavy and large) and should fit in the 14 original alfa 33 alloy rims..
this should give 25% more brake power from the calipers
and another 10% more power from the bigger than original disks,
but may be I should also change the rear hydraulic drum pistons
from original 17 mm diameter to 19 mm to achieve some equilibrium,
so this seam to me a quite big time consuming work..

- use a more powerful brake vacuum booster;
actually also a small 900 kg car have usually
at least a 9 inch single booster or a 8 inch tandem (double) one..
this should give from 70% to 100% more power help at the pedal,
actually I'm searching for this solution as i don't feel real need
for bigger disk, motor is 1.3 and with 14 rims (more vented than
the 13 ones) on my 33 I don't have serious brake fading problems..

[BigAl]

Very different interior
I would leave the rear alone, as standard there is too much rear braking force. Looking forward to your decision. I want to keep to 14" when on track so I havent gone big brakes.
Only problem I see is increasing braking force, as in making pedal more efficient, could lead to locking up.
_________________
x2 33 16v
pictures http://www.alfa-pages.co.uk/viewtopic.php?t=5203

[33bits]

Hi, yes Al is right, I have fitted 4 pot callipers to my 33 16v and the pedal travel was increased, I fitted a master cylinder from a 75 as the internal bore is 3mm bigger (22mm). This really sorted out the extra pedal travel.
The overall result of doing this conversion is the brakes are now much stronger but there isn't a lot of feel throughout the pedal travel up to the point where the car actually begins to slow down. It's a bit like the first few inches of pedal travel have no affect on the braking & then all of a sudden it just stops. This sounds like a bad thing but it didn't take long to get used to this & after driving my other halves 33 (with standard brakes) I would do this conversion to hers with no hesitation. Hope this makes sense.
_________________
155 sportpack
33 16v Sportwagon
33 Permanent 4
33 16v (for sale)
156 JTS sportwagon
contact me for any 33 parts. Alex, 07896-327708

[Brit01]

Hi guys,

I'm looking for a new/used servo for my 33 series 2. No luck so far locally.
Might be easier to get a 75 booster.

Did you manage to fit the 75 booster to the 33?

Was it a straight fit? Any modifications done?

Enhanced braking?

Thanks

Chris
_________________
S2 33 1988 1.7 QV
Dellorto DRLA40 (32mm venturi)

[Bobkelso]

Hi Brit,
what about to get your booster have a complete revision in a brake center?
If they can have the spares kit (common for many booster model of same size)
sound like the less expensive choice and you will get a brand new booster,
instead of buy one used with the risk is not 100% perfect.

But in case you or someone in the near future would try the alfa 33 booster upgrade,
I put here the link at the other post were another half discussion about
the booster upgrade is been done, with a description of the various available booster
more correct than what I have done at the beginning of this post some time ago.

http://www.alfa-pages.co.uk/viewtopic.php?p=37679#37679

Ps.: in that linked discussion I have just corrected my yesterday text to make
my English a little more clear (I hope), unfortunately also the upgrade
with the alfa 75 booster it is not a straight fit and I doubt someone have already done it.
To make it work it would be necessary to have one spare frame from a donor 33 to adapt it
(I mean the black frame where are attached the brake booster on one side and the 3 pedals on the other side).

[Brit01]

I have found a brake specialist who can rebuild them very well.
Will go to the garage soon for an overhaul.
Get the oil pump changed and maybe the water pump if can get one locally.

Cheers
_________________
S2 33 1988 1.7 QV
Dellorto DRLA40 (32mm venturi)

[Bobkelso]

Seams a good choice.

I verified on manuals that the value of air depression
after the butterfly valve for example in alfa 33 1.3 i.e.
with motor at idle is -0.5 bar (at idle the revs are low
but butterfly valve closed rise the air depression value)
so I expect normal operation values of air depression
for a brake booster is from a minimum of -0,5 bar
to may be -0,6-0,7 maximum bar at some revs

When you go for the booster repair eventually
can you ask at the booster specialist if a small optional
air depression pump moved by a belt (the belt type is the one
that was used in many old diesel car) can do significantly
better and improve the brake booster assistance or
if the difference in air depression values is marginal?
Just to know it..

[Brit01]