
oldsmobile-digest       Thursday, June 10 2004       Volume 01 : Number 4915



RE: disc brake master cylinders
15" steelies with poverty caps
74 - 81 rear ends
Re: Intrigue Headlights
Re: Intrigue Headlights
Re: 15" steelies with poverty caps
i have to sell my cars
Re: tuning with a vacuum gage
OAI pin won't release
Re: 15" steelies with poverty caps
RE: disc brake master cylinders
RE: 76 Toronado For Sale - RARE version
Re: Intrigue Headlights
Re: 15" steelies with poverty caps
Re: Intrigue Headlights
Re: 74 - 81 rear ends
Re: Intrigue Headlights
Fuel Pump FYI
Re: 74 - 81 rear ends
Re: disc brake master cylinders
Re: disc brake master cylinders

----------------------------------------------------------------------

Date: Wed, 9 Jun 2004 14:34:37 -0700 (PDT)
From: chris smetana <grp442@yahoo.com>
Subject: RE: disc brake master cylinders

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Typically, there is a difference.  Not necessarily in the piston size 
or 
stroke, but a difference in the way the rod is located on the back 
side.  
Manual systems of that era tend to use a longer rod from the pedal and 
it 
rests in a fairly deep recess in the back of piston.  This keeps the 
rod 
from falling out.  A power master cylinder will have a shallow indent 
for 
the rod from the booster to contact.  When using a master cylinder from 
a 
power set up, you will need to address the rod retention, so it does 
not 
drop out of place.  This is a big safety issue.
- ---------------------------------------------------------------
AH HA!!!!! I see what you are saying.
 
 

I would suggest picking up the correct style master cylinder from NAPA 
or 
whoever and either a correct rod or lengthen the one you have to the 
correct 
length.  Some folks make a bracket with a hole to support the shorter 
rod 
when using a power style master cyl., but it gets real close under the 
dash 
and it may or may not work.
- ----------------------------------------
I have the longer rod in my manual drum brake equipped 70 F-85.  Or I should have it.  But using the power disc brake master, because of the shallow recess, would/could cause a problem.
 


One other thing, you may need to relocate the rod to a higher hole on 
the 
brake pedal.  Not real sure about this on A bodies, but I know you need 
to 
on a G body.  I assume they are similar in this area.  The non power 
assist 
needs more leverage and the higher hole provides it.
- ----------------------------------------------------------------------------
A-bodies are the same way, this much I do know.  There are two holes on the brake pedal.  Upper is for manual brakes, lower is for power brakes. (I think, need to poke my head under the dash)  But since I'm going from manual drum, to manual disc, that isn't an issue for me.
 
Thanks Dave.  btw, I need to figure out how to get my movie file to play before I can let you hear the video clip of my engine running.  something about a decompression error.
 
Chris
grp442@yahoo.com

		
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<DIV>Typically, there is a difference.&nbsp; Not necessarily in the piston size <BR>or <BR>stroke, but a difference in the way the rod is located on the back <BR>side.&nbsp; <BR>Manual systems of that era tend to use a longer rod from the pedal and <BR>it <BR>rests in a fairly deep recess in the back of piston.&nbsp; This keeps the <BR>rod <BR>from falling out.&nbsp; A power master cylinder will have a shallow indent <BR>for <BR>the rod from the booster to contact.&nbsp; When using a master cylinder from <BR>a <BR>power set up, you will need to address the rod retention, so it does <BR>not <BR>drop out of place.&nbsp; This is a big safety issue.<BR>---------------------------------------------------------------</DIV>
<DIV>AH HA!!!!! I see what you are saying.</DIV>
<DIV>&nbsp;</DIV>
<DIV>&nbsp;</DIV>
<DIV><BR>I would suggest picking up the correct style master cylinder from NAPA <BR>or <BR>whoever and either a correct rod or lengthen the one you have to the <BR>correct <BR>length.&nbsp; Some folks make a bracket with a hole to support the shorter <BR>rod <BR>when using a power style master cyl., but it gets real close under the <BR>dash <BR>and it may or may not work.</DIV>
<DIV>----------------------------------------</DIV>
<DIV>I have the longer rod in my manual drum brake equipped 70 F-85.&nbsp; Or I should have it.&nbsp; But using the power disc brake master, because of the shallow recess, would/could cause a problem.</DIV>
<DIV>&nbsp;</DIV>
<DIV><BR><BR>One other thing, you may need to relocate the rod to a higher hole on <BR>the <BR>brake pedal.&nbsp; Not real sure about this on A bodies, but I know you need <BR>to <BR>on a G body.&nbsp; I assume they are similar in this area.&nbsp; The non power <BR>assist <BR>needs more leverage and the higher hole provides it.<BR>----------------------------------------------------------------------------</DIV>
<DIV>A-bodies are the same way, this much I do know.&nbsp; There are two holes on the brake pedal.&nbsp; Upper is for manual brakes, lower is for power brakes. (I think, need to poke my head under the dash)&nbsp; But since I'm going from manual drum, to manual disc, that isn't an issue for me.</DIV>
<DIV>&nbsp;</DIV>
<DIV>Thanks Dave.&nbsp; btw, I need to figure out how to get my movie file to play before I can let you hear the video clip of my engine running.&nbsp; something about a decompression error.</DIV>
<DIV>&nbsp;</DIV>
<DIV>Chris</DIV>
<DIV><A href="mailto:grp442@yahoo.com">grp442@yahoo.com</A></DIV><p>
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------------------------------

Date: Wed, 9 Jun 2004 14:38:36 -0700 (PDT)
From: Matt Crumley <crumleym_50@yahoo.com>
Subject: 15" steelies with poverty caps

Dave and others,

I've never seen a 15" diameter steel wheel with
poverty caps, only 14" on F85's and whatnot.  He
stated that they were made custom and were 8" wide. 
He was sporting BFG Drag radials comparable to
275/60/15's.

Matt


	
		
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------------------------------

Date: Wed, 9 Jun 2004 17:51:51 -0400
From: "Tour Op & Travel Agency Trade 2000" <travelchile@manquehue.net>
Subject: 74 - 81 rear ends

Hi all,
What are the chances the 74 8.5" rear end will fit into the 81 CS?
THe 468 is being installed now in the 81 CS... tight fit, some problems with
the pulleys alignement, we'll see how it goes on... strangely, the exhaust
manifolds from the 81 260ci are the same that those from the 76 455...???
rgds
Matt

------------------------------

Date: Wed, 9 Jun 2004 19:04:15 -0300 (ADT)
From: Greg Beaulieu <ab348@chebucto.ns.ca>
Subject: Re: Intrigue Headlights

On Tue, 8 Jun 2004 62oldsfan@comcast.net wrote:
> Um, GM does not service these lamps in pieces.  You buy a whole assembly.  I
> don't think it's something I'd want to be taking apart...

In that case then, I may have a warranty claim. There appears to be some
sort of deposit on the reflector and/or lens around the area of the amber
turn signal/running light. Why, I dunno.

Greg Beaulieu    ab348@chebucto.ns.ca    Dartmouth, Nova Scotia, Canada
          Olds List Admin Info: http://oldslist.oldsgmail.com

------------------------------

Date: Wed, 09 Jun 2004 22:37:21 +0000
From: Steve Harrison <k0xp@dandy.net>
Subject: Re: Intrigue Headlights

At 08:59 PM 6/9/2004 +0000, you wrote:
>>The headlight units themselves pop out of the car
>>easily, but does anyone know how easy/hard it is to
>>remove the lenses from the assemblies? It looks like
>>they just snap on, but I dunno about sealants, gaskets,
>>hidden tricks, etc. Any assistance appreciated.
>
>If they're similar to those of Bonnevilles and the second-generation plastic 
>minivans, it is true that there are spring clips around the perimeter, but 
>AFAIK they were only used to hold everything together while the sealer sets 
>up. In other words, they're glued together permanently; the spring clips are 
>there mainly to ensure that everything stays in alignment throughout, and 
>that the assemblies can be packed for shipping as soon as they're glued 
>together.

That's also true of the composite HLs used on '87/'88 Cutlii/442 as well as
those on the fullsized wagons of '88-'90. I tried working the outer glass
lens loose from one a few years back.... used an Exacto knife to cut
through the sealant, pried and pried and finally gave up when I became
convinced it just wouldn't come apart without chipping/cracking.

Once you begin developing that grayish corrosion tint inside, I don't think
you can either arrest further corrosion nor reverse it. It's done fer; go
get a 2nd mortgage or sell yer 2nd-born and go buy a new HL housing  ;o(((((

SteveH

------------------------------

Date: Wed, 09 Jun 2004 21:00:17 -0400
From: Robert Barry <rbarry@postoffice.providence.edu>
Subject: Re: 15" steelies with poverty caps

At 05:38 PM 6/9/2004, you wrote:
>Dave and others,
>
>I've never seen a 15" diameter steel wheel with
>poverty caps, only 14" on F85's and whatnot.  He
>stated that they were made custom and were 8" wide.
>He was sporting BFG Drag radials comparable to
>275/60/15's.

I'm quite sure the Malibus and Buicks in the mid-70's had them; granted, 
they weren't as common as the full wheelcovers, but there certainly were 
15" poverty-cap wheels. Now whether they would fit the early poverty-caps 
is another issue. They certainly weren't 8" wide, though.


_______________________________________
Bob Barry  MailTo:rbarry@providence.edu
http://home.off-road.com/~wagoneer/ 

------------------------------

Date: Wed, 9 Jun 2004 22:35:48 EDT
From: DROLDS350@aol.com
Subject: i have to sell my cars

 

------------------------------

Date: Wed, 9 Jun 2004 22:38:07 EDT
From: DROLDS350@aol.com
Subject: Re: tuning with a vacuum gage

- --part1_12e.43bc94c4.2df9238f_boundary
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a 1970 w31 and rally 350 that have to go , my son is off to college so im 
putting the cars up for sale . many of you have seen them . any interest , e mail 
me privately
thanx
  jim mckeague
 drolds350@aol
 waubonsiehockey@aol

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<HTML><FONT FACE=3Darial,helvetica><HTML><FONT  SIZE=3D2 PTSIZE=3D10 FAMILY=
=3D"SANSSERIF" FACE=3D"Arial" LANG=3D"0">a 1970 w31 and rally 350 that have=20=
to go , my son is off to college so im putting the cars up for sale . many o=
f you have seen them . any interest , e mail me privately<BR>
thanx<BR>
&nbsp; jim mckeague<BR>
 drolds350@aol<BR>
 waubonsiehockey@aol</FONT></HTML>

- --part1_12e.43bc94c4.2df9238f_boundary--

------------------------------

Date: Thu, 10 Jun 2004 09:04:29 EDT
From: Jon442@aol.com
Subject: OAI pin won't release

- -------------------------------1086872668
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My right OAI pin won't release. It feels like one side is releasing, and 
wants to pop up, but the other side feels like the pin is still caught in the 
bracket, and no matter how much I wiggle it, it won't release. Any ideas?

Jon Wessel

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Content-Type: text/html; charset="US-ASCII"
Content-Transfer-Encoding: quoted-printable

<HTML><HEAD>
<META charset=3DUS-ASCII http-equiv=3DContent-Type content=3D"text/html; cha=
rset=3DUS-ASCII">
<META content=3D"MSHTML 6.00.2800.1400" name=3DGENERATOR></HEAD>
<BODY style=3D"FONT-SIZE: 10pt; FONT-FAMILY: Arial; BACKGROUND-COLOR: #fffff=
f">
<DIV>My right OAI pin won't release. It feels like one side is releasing, an=
d wants to pop up, but the other side feels like the pin is still caught in=20=
the bracket, and no matter how much I wiggle it, it won't release. Any ideas=
?</DIV>
<DIV>&nbsp;</DIV>
<DIV><FONT lang=3D0 face=3DArial size=3D2 FAMILY=3D"SANSSERIF" PTSIZE=3D"10"=
>Jon Wessel</FONT></DIV></BODY></HTML>

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------------------------------

Date: Thu, 10 Jun 2004 08:35:20 -0500
From: "Dave Wyatt" <wyattolds@hotmail.com>
Subject: Re: 15" steelies with poverty caps

Full Size Chevy wagons used a 15 X 7 steel wheel in the early 70's.  They 
had the 4 3/4 bolt pattern for a while, before they switched the full size 
Chevies to the larger bolt pattern.  The GM centers, with the bumps pointing 
out, are all the same as far a dog dish caps were concerned.  1954 was the 
first year for the modern style dog dish cap on Chevies, but I'm not sure 
about the other GM makes.  Later when Chevy came out with the rally rim, it 
actually used the older style cap retention with the bumps pointing in.

Yes, 15X8.5's are definitely custom made, but the centers should not be too 
hard to find if someone wanted to make a set.



Dave Wyatt
70  4-4-2
67 Vista Cruiser





>From: Robert Barry <rbarry@postoffice.providence.edu>
>Reply-To: oldsmobile@chebucto.ns.ca
>To: oldsmobile@chebucto.ns.ca
>Subject: Re: 15" steelies with poverty caps
>Date: Wed, 09 Jun 2004 21:00:17 -0400
>
>
>I'm quite sure the Malibus and Buicks in the mid-70's had them; granted, 
>they weren't as common as the full wheelcovers, but there certainly were 
>15" poverty-cap wheels. Now whether they would fit the early poverty-caps 
>is another issue. They certainly weren't 8" wide, though.

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------------------------------

Date: Thu, 10 Jun 2004 08:38:41 -0500
From: "Dave Wyatt" <wyattolds@hotmail.com>
Subject: RE: disc brake master cylinders

It sounds as if you are halfway home with the swap, other than locating the 
correct master cylinder.  I went through all kinds of hoops when I did my 
Malibu conversion trying to find a suitable MC.  At least you are working 
with a set up GM actually made.


Dave Wyatt
70  4-4-2
67 Vista Cruiser

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------------------------------

Date: Thu, 10 Jun 2004 09:51:27 -0400
From: "Christopher Witt" <rocketscience442@hotmail.com>
Subject: RE: 76 Toronado For Sale - RARE version

Date: Tue, 8 Jun 2004 14:42:25 -0700
From: "Schopen, Kenneth" <kenneth.schopen@medtronic.com>
Subject: RE: 76 Toronado For Sale

>Original 455 motor and turbo 400 tranny.
++++++++++++++
One of those ultra-rare RWD Toros, eh?
Kenneth
Phoenix, AZ
==================
Oh, yeah, only available on the 4-door, Station Wagon, convertible, or 2-bbl 
Toronados!
HELLA rare. I have only heard of them, yet I have laid hands upon the Hemi 
455, and have SEEN the fabled Solid Main Web 403!
- ----------------------
Chris Witt
1303 W. Miller Rd.
Lansing MI 48911

RocketScience442@hotmail.com

Cell 517-449-0432 weekends or short weekday calls or leave message.
Home 517-882-9747 thru 10-11pm MI time most days

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------------------------------

Date: Thu, 10 Jun 2004 09:58:40 -0400
From: "Christopher Witt" <rocketscience442@hotmail.com>
Subject: Re: Intrigue Headlights

Subject: Re: Intrigue Headlights

>The headlight units themselves pop out of the car
>easily, but does anyone know how easy/hard it is to
>remove the lenses from the assemblies? It looks like
>they just snap on, but I dunno about sealants, gaskets,
>hidden tricks, etc. Any assistance appreciated.
===============
what about removing the assembly, open it up, swish some windex solution 
about the inside, then dry it all out with the hair drier or similar warm 
air flow?

Practice on a spare scrap unit perhaps, a broken one at the Yarde? Or, 
extract one at the Yarde, try that on-site, see if it looks like there's any 
hope of improvement.

Or, just buy new ones. How much can that possibly be, $800-1000 or so?
- ----------------------
Chris Witt
1303 W. Miller Rd.
Lansing MI 48911

RocketScience442@hotmail.com

Cell 517-449-0432 weekends or short weekday calls or leave message.
Home 517-882-9747 thru 10-11pm MI time most days

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------------------------------

Date: Thu, 10 Jun 2004 11:53:58 -0400
From: SteveH <k0xp@dandy.net>
Subject: Re: 15" steelies with poverty caps

At Thursday, 10 June 2004, you wrote:

>Full Size Chevy wagons used a 15 X 7 steel wheel in the early 70's.

They still did, at least from at least '86-'90. Stock tire size was 
225/75-15. I suspect 15x7 was stock size from sometime like '77-'90.


SteveH



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------------------------------

Date: Thu, 10 Jun 2004 11:57:36 -0400
From: SteveH <k0xp@dandy.net>
Subject: Re: Intrigue Headlights

At Thursday, 10 June 2004, you wrote:

>Subject: Re: Intrigue Headlights
......
>what about removing the assembly, open it up, swish some 
>windex solution about the inside, then dry it all out 
>with the hair drier or similar warm air flow?

The aluminized reflective coating inside corrodes; doesn't shine 
up no how, no way  ;o( Even if you can get to it and try polish on 
it, the shiny surface is gone.

>Or, just buy new ones. How much can that possibly be, 
>$800-1000 or so?

Probly. About a tenth of that for '88-'90 Crapice wagons ;o(((((

What you have to watch out for is a pebble causing a small hole or 
chip in the glass; that will allow moisture inside el pronto and 
within a few months, the shiny surface is gone  ;o(  The last time 
that happened to me, I only put a piece of tape over the hole and 
had to keep replacing the tape every few weeks. Next time, I'll epoxy 
over the hole and hope it lasts longer.

SteveH



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------------------------------

Date: Thu, 10 Jun 2004 14:11:09 -0400
From: "Bill Reilly" <william.reilly@comcast.net>
Subject: Re: 74 - 81 rear ends

Matt,

The '74 rear will not bolt up directly to your '81 Cutlass.

As for the pully alignment, you have to be careful with the waterpump. There
were two types, one was shorter than the other by a fraction of an inch, but
that will make all the difference in the world on getting that pulley to
line up.

And most of the exhaust manifolds from all usual Olds V8s will "interchange"
with each other, as the exhaust ports on the heads were in the same
location. The ones to be careful not to use are the stainless steel tube
design used on the '85 and older roller 307. And altough they fit the
exhaust manifolds from the smaller engines will not flow as well as those
designed for the BB.

I'm using maifolds from the early 307 on the 455 in my '85 Cutlass and I
believe they are hurting the amount of power I get to my rear wheels.  One
of those things on my list of things to change, eventually.

Bill Reilly
'85 Cutlass Supreme

- ----- Original Message -----
Subject: 74 - 81 rear ends


> Hi all,
> What are the chances the 74 8.5" rear end will fit into the 81 CS?
> THe 468 is being installed now in the 81 CS... tight fit, some problems
with
> the pulleys alignement, we'll see how it goes on... strangely, the exhaust
> manifolds from the 81 260ci are the same that those from the 76 455...???
> rgds
> Matt
>

------------------------------

Date: Thu, 10 Jun 2004 18:33:20 +0000
From: "Andrew C. Green" <acg_o@hotmail.com>
Subject: Re: Intrigue Headlights

>What you have to watch out for is a pebble causing a small hole or
>chip in the glass; that will allow moisture inside el pronto and
>within a few months, the shiny surface is gone  ;o(  The last time
>that happened to me, I only put a piece of tape over the hole and
>had to keep replacing the tape every few weeks. Next time, I'll epoxy
>over the hole and hope it lasts longer.

Ah. Been There; Done That; Got the T-shirt. I had a stone punch in one of 
the Bonneville headlamps: a little hole on the outside but a large 
saucer-shaped chip out the back of the glass, rattling around inside the 
headlamp.

Gluing the piece back into the hole was not an option, for reasons I don't 
recall. (I think it had broken up.) So I stuck a piece of clear tape over 
the outside hole, then removed the headlamp and laid it face-down on a shop 
rag. I then put a blob of clear silicon sealer on the end of a popsicle 
stick, and used that to fill the hole from the back side of the glass, 
reaching through one of the socket holes with the popsicle stick. The tape 
on the outside sealed the hole to keep the goop in place until it set. I 
left the headlamp face-down overnight to cure, reinstalled it the next day, 
and it's been fine ever since.

- -- Andy

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------------------------------

Date: Thu, 10 Jun 2004 16:04:11 -0400
From: "Paul Tumolo" <ptumolo@comcast.net>
Subject: Fuel Pump FYI

When I was running my engine on the dyno, it would have a serious lean
out condition about 4500 RPM. The dyno guy ruled out the carb and float,
so all fingers pointed toward the fuel pump. It couldn't be.....brand
new AC Delco # 41567.

I install the new engine in the car (with the same pump). Runs great,
and has plenty of power to 4500 RPM and it falls flat on it's face. So,
I figure that it is the pump, and go tot the auto parts store to get
another one. When I tell the parts guy what I want, he looks it up on
the computer. He lists a part number 40736.....Hmmm, 442 only
application. So, I buy it.

When I compare it to the 41567, I am shocked! The diaphragm on the 40736
is about 3X bigger than the 41567.

This large diaphragm pump looks to be the ticket for high performance
use.

Paul Tumolo
1970 442 Hardtop
OCA # 31967 

------------------------------

Date: Thu, 10 Jun 2004 16:12:54 -0400
From: "Tour Op & Travel Agency Trade 2000" <travelchile@manquehue.net>
Subject: Re: 74 - 81 rear ends

Bill - Thanks a lot!
I thought, that the exh ports of BB would be bigger than those from the 260
hence a different exh manifold. I will watch this water pump issue - I've
got 3 of them now 260-81, 455-68 and 455-76 - one could fit :-)...  not a
chance, they are all identical, bad luck...
With the rear ends I guess it will be possible to switch them from one car
to another cutting and fixing again the ancle points for each part. But it
would mean that the 81 rear end will be longer and differently attached to
the body - possible stability problems.
Any chances the 7.5 could be made tough enough to live a streeet driven
468ci?
I would like the Eaton posi with some shorter gears like 3.08 which implies
bigger bearings as well...
rgds
Matt
> The '74 rear will not bolt up directly to your '81 Cutlass.
>
> As for the pully alignment, you have to be careful with the waterpump.
There
> were two types, one was shorter than the other by a fraction of an inch,
but
> that will make all the difference in the world on getting that pulley to
> line up.
>
> And most of the exhaust manifolds from all usual Olds V8s will
"interchange"
> with each other, as the exhaust ports on the heads were in the same
> location. The ones to be careful not to use are the stainless steel tube
> design used on the '85 and older roller 307. And altough they fit the
> exhaust manifolds from the smaller engines will not flow as well as those
> designed for the BB.
>
> I'm using maifolds from the early 307 on the 455 in my '85 Cutlass and I
> believe they are hurting the amount of power I get to my rear wheels.  One
> of those things on my list of things to change, eventually.
>
> Bill Reilly
> '85 Cutlass Supreme
>
> ----- Original Message -----
> Subject: 74 - 81 rear ends
>
>
> > Hi all,
> > What are the chances the 74 8.5" rear end will fit into the 81 CS?
> > THe 468 is being installed now in the 81 CS... tight fit, some problems
> with
> > the pulleys alignement, we'll see how it goes on... strangely, the
exhaust
> > manifolds from the 81 260ci are the same that those from the 76
455...???
> > rgds
> > Matt
> >
>
>

------------------------------

Date: Thu, 10 Jun 2004 17:07:14 -0400
From: Doug Ahern <doug.ahern@usg.edu>
Subject: Re: disc brake master cylinders

On 25 06/08/04, chris smetana wrote:
> Whelp, I had to do a quickie front brake repair to the 70 F-85 last night.  Glad I made it home from work though.  I knew I was on borrowed time with the front brakes, but was hoping it could wait a week.  Well, she had a mind of her own.  I'm planning on swapping the current manual front drums to manual discs using a power disc brake setup from a 71 LeMans parts car I have.  My question, which I haven't had time to research myself, but figured I'd ask here is, is there a difference between a manual and power disc brake master cylinder?  I'm debating on rebuilding the current power disc brake master cylinder and putting it on my F-85 but keeping the manual brakes just discs.  I'm pretty sure there isn't but I need to double check.
>  

there are two things to check on, neither or which I can speak of in
an authoritative manner regarding Oldsmobiles.  

many drum brake systems of the 60s/early 70s made use of "residual
pressure valves".  these are small valves (internal or external to
the MC) that maintain a small amount of pressure in the hydraulic
system to help keep the wheel cylinder seals tight against the cylinder
and was a measure to prevent leaks.  Of course this wasn't enough pressure
to overcome the springs and move the shoes into the drums.  With disc 
brakes, the residual pressure valves were not needed.   when using a drum
brake MC on discs, if the residual pressure valve isn't removed,  the
pads will aways be exerting themselves on to the rotor (moreso than when
they are just rubbing them...).   In the mid 70s, drum brake wheel cylinder
seal technology changed to do away with the residual pressure valve on
the rear drums.  I konw that Bendix and Kelsey Hayes systems for Chrysler
and Ford used residual pressure valves,  I'm not sure about GM.  can anyone
chime in?

the other difference is fuild displacement. on drum brake cars, the front
and rear reserviors are equally sized,  on disc brake cars, the reservior
serving the discs is larger.  I think this is because the discs require
more fuild to delieved to the calipers than drum wheel cylinders.

did GM make any manual brake master cylinders for discs?   I know that
Chrysler built all disc cars with power brakes until about 74 or so, 
when the Valiant/Darts were offered with manual discs (larger dia. 
piston in the MC than power assist MCs).  what about GM?   every 
disc brake A-body I've come across has had a power booster.  same
goes for 70's Novas/Apollos/Venturas....

Doug Ahern
Athens, GA (64 Cutlass)

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Date: Thu, 10 Jun 2004 18:59:19 -0300 (ADT)
From: Greg Beaulieu <ab348@chebucto.ns.ca>
Subject: Re: disc brake master cylinders

On Thu, 10 Jun 2004, Doug Ahern wrote:
> did GM make any manual brake master cylinders for discs?   I know that
> Chrysler built all disc cars with power brakes until about 74 or so, 
> when the Valiant/Darts were offered with manual discs (larger dia. 
> piston in the MC than power assist MCs).  what about GM?   every 
> disc brake A-body I've come across has had a power booster.  same
> goes for 70's Novas/Apollos/Venturas....

Well, the '70 W-31 cars didn't make enough vacuum to run a power booster
so they could be had only with manual discs IIRC. Would that still be
available? 

Greg Beaulieu    ab348@chebucto.ns.ca    Dartmouth, Nova Scotia, Canada
          Olds List Admin Info: http://oldslist.oldsgmail.com

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End of oldsmobile-digest V1 #4915
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