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Gents, was looking for a photo/photos, (or info leading to), the brake booster/clutch system (hole location) as a reference point where the hyd. master cylinder/push rod goes, relative to the brake hole. Would appreciate an under hood shot of the hyd. reservoir as it's attached to the M/C, or an empty firewall, where the holes are. Converting my 84 T/A to a T-5, and need to know what this system looks like in place, if some-one parted a car, and has the nose off to see what the firewall looks like on a stick shift car. Thanks for any replies.
This is a poor picture, cause the wiring harness is in the way of where the clutch MC would be, but I hope you get the idea.
OMG (!), a reply! GT, you are the man. Thanks a ton. Seriously. I picked up the system below today, and am curious how the master cylinder is affixed, (and where) to the firewall. Your pic is a start. The hose is so long from the bottom of the reservoir, one would think the MC is down much lower, but don't see how it would connect to the pedal. I think there's a schematic here, that I'll need to find. Thank you again.
This is out a Chilton's manual. Having no experience with converting from auto to manual I would guess you will need to install the pedal to approximate where the rod for the master will go through the firewall.
Originally Posted by tajoe
Gents, was looking for a photo/photos, (or info leading to), the brake booster/clutch system (hole location) as a reference point where the hyd. master cylinder/push rod goes, relative to the brake hole. Would appreciate an under hood shot of the hyd. reservoir as it's attached to the M/C, or an empty firewall, where the holes are. Converting my 84 T/A to a T-5, and need to know what this system looks like in place, if some-one parted a car, and has the nose off to see what the firewall looks like on a stick shift car. Thanks for any replies.
This is a poor picture, cause the wiring harness is in the way of where the clutch MC would be, but I hope you get the idea.
These are from a Haynes repair manual I have....
Last edited by Scott's 83' Z; 07-20-2022 at 05:18 PM.
You guys are getting me closer. Much appreciated. Still having a hard time figuring out exactly where the MC is located on the FW.
Also Scott, on the blowup above of the hyd. system, it shows the pedal/pushrod attachment point. They show a small short tab on the pedal lever, probably welded on, and sticking rearwrd a small amount. Then the MC pushrod attaches to it. On my clutch pedal/brake assembly, (not original to the car), the lever has a hole in it. like the mechanical system on your lower picture. (And probably what your 83 has(?). Not sure how critical that is, but is something for me to consider.
Bear in mind, that as can be seen in the pic, the factory manual shift cars had a "Doubler" tack welded to the firewall to try to prevent the firewall from flexing when the clutch pedal gets pushed. You will want to recreate that doubler to keep the metal from cracking in that area.
Wow! Fantastic find OB. I can't believe the MC is mounted that low, under the brake MC. I can't even fathom the angle the push-rod is at, to the clutch pedal lever. amazes me it even works. Maybe when I install it, it'll be more obvious. I'm not sure where the sheet metal is beefed up. I don't notice its location in the photo. Is it the out-line I'm seeing around where the MC is only, (the 2 diagonal holes, and one middle one?). It looks like it extends up under the brake MC mounting area. But also, thank you a ton for the info. It'll help not just me, but many who wanna try this swap.
Wow! Fantastic find OB. I can't believe the MC is mounted that low, under the brake MC. I can't even fathom the angle the push-rod is at, to the clutch pedal lever. amazes me it even works. Maybe when I install it, it'll be more obvious. I'm not sure where the sheet metal is beefed up. I don't notice its location in the photo. Is it the out-line I'm seeing around where the MC is only, (the 2 diagonal holes, and one middle one?). It looks like it extends up under the brake MC mounting area. But also, thank you a ton for the info. It'll help not just me, but many who wanna try this swap.
Hi Joe, yes the stiffened area is where you describe, if you look close at the pic the raised area around the clutch MC and extending up to the brake MC is the doubler.
I'm wondering if the stiffener patch would work on the eng. side of the firewall. It might be easier for me to tack it there, than under the dash, seeing all the wiring and steering column is in place. I have the booster off, and plan on pulling the motor soon. Curious if the brake booster has the same concern on the FW. Maybe the engineers figure the bracket hanging the brake pedal/booster bracket is the load bearer.
Also, I've heard people mention the clutch MC has a bracket that shouldn't be omitted. Is the one being mentioned, shaped like a muffler clamp U-bolt, that goes on the eng. side of the FW? (Around the MC) Or one that I think I've seen in a schematic, that goes under the dash. It appears to run on a diagonal from the lower part of the firewall, up to the pedal bracket assy. (#7 in the Haynes schematic above.)
I guess all those stiffeners is a testimony to how light the 3rd gens are. The uni-body is made of cheese, and wasn't designed for a stick-shift. It seems like a clutch was kinda forgotten in the designing stage, and thrown in at the last minute. Such a shame, cause to me a performance car, (especially one made for the road, like an F-body) should have 3 pedals. I realize that stick shifting is a lost art, (like wood working with hand tools, oil painting, playing a piano...ect...) and most buyers, (especially today) don't care, and would prefer an automatic. But with the help of you fine people on this site, at least I'll be able to retrofit one to mine. Still very appreciative to all involved.
(thanks mods) )
I tried to edit this photo on my photo-bucket site, and of course, it wouldn't take the change. What I tried to do was use a marker , and circle a section of this picture, so you could understand what I'm talkin about. But I guess I'll have-ta guide you with words. (Sorry).
Anyway, loaded with OBs photo of the firewall, with the clutch MC oval hole and the 2 diagonal ones for the external stiffener brace, I went looking under my dash, and under the hood for some kinda factory markings, plugs, or anything to help with the "exact" mounting of the MC. But came up empty handed. As a matter of fact, is the firewall "double walled"? It appears to be on mine, if I'm looking at it correctly. Can't say for sure...yet. Thinking of drilling in it, just to confirm.
If you'll notice in this photo, under the brake MC mounting hole, there's an empty area, (I think the only empty spot on the entire firewall). Can never be seen with the brake booster in place. If you look down below that area, you'll see the grommet for the speedo cable. Just to the right of that, there's a coin sized and shaped factory "bump". At 1st I thought it was a rubber plug, and maybe something for the clutch system. As I pried on it, and then chiseled it lightly, I see it's not rubber or plastic, but metal. Not sure what it's purpose is. Guess I'll have-ta continue exploring.
Last edited by tajoe; 07-23-2022 at 04:24 PM.
Reason: improperly placed post
First off, the pic I found of a chunk of the firewall (Not my pic, just what came up in a Google search) is being shown from looking at the firewall from inside the car (looking at it from under the dashboard VS looking at it from the engine side) and so the doubler wouldn't be seen under the hood, it would be under the dash. The doubler will not be on your car and the clutch master cylinder holes wouldn't be pre drilled, pre punched, or marked for such in any way, since your car was built with an automatic. I wish I could find it, but I can't, I recall seeing in the transmission subforum here a template someone posted of exactly where to drill the holes, perhaps if you start a thread in the transmission area asking for the template someone might post it up for you.
Second thought, in your pic the firewall is looking kinda crusty (rust/possible rot?) where it meets the rest of the body near where the cruise control harness passes through the firewall. IS it that rusted or is that just an oddity of the pic? If it really is as punky there as it looks, a bit of metalwork coupled with some rust preventative really should be on your "to do" list. That kinda rust/rot tends to go like wildfire once it gets established and should be taken care of soon....
Hello OB, once again you've just educated me more about this car. You commented on the "cruise control" harness, which I didn't even know this car had.
I don't know if I mentioned it, but this car was given to me by a good friend, (almost 10 yrs ago) because the TH700 went bad, and he didn't wanna fix it. I've only driven it a few times in it's life, when I would do repairs to it. (B4 I acquired it) I've seen the actuator up by the radiator support, LHS, behind the hidden headlight, and for some stupid reason, thought it activated the pop-up headlights. Now that you mentioned it, I followed the cable to the carb., and understand it. Another well deserved "thanks".
As for rot, this car has very little. Has spent most of it's life garaged, and was owned by an older gentlemen. there is some dirt, and debris that's been collecting since it's been sitting, and a touch of minor surface rot, but nothing serious. The floors and firewall are clean, but some of the body sheet metal has some paint lifted, that I've scraped and temporarily sealed off. But I appreciate the advice to get ahold of it, B4 it advances.
And I understand the photo you posted of the FW is from the inside, (under the dash) and it's really helpful. I also understand it wouldn't have the stiffeners. But was really hoping there would be some markings, (indentations) on mine, for the clutch MC. But it appears it doesn't. It sure would be nice if I could find that template you mentioned. I'll try researching that, and let you know what I come up with. Was wundering if you knew what that bump was for, that I commented on in my above post. I mistakenly said the bump was next to the speedo cable grommet, but is actually next to the cruise harness, that you spoke of.
I just came in from a few hrs of pulling poison sumac trees, and roots, in poison ivy patches, from the woods on my property, with my 93 military issue 6.2 2500 stakebed. And it's about 85° outside. i'm beat, but checked my Email, and saw your posting. You are quite the investigator OB. I'll be checking them out tomorrow. i'll never be able to thank you enuff for your help. But I'll try. Enjoy your Sunday bud.
07-18-2022, 03:45 PM
