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Re: Junkyard F23 transmission and engine advice.
Posted: Fri Sep 05, 2014 10:08 pm
by fieroguru
The Dark Side of Will wrote:
I don't see any reason this part couldn't be turned from hex (heck, even square) brass bar on a lathe.
It can be... I had a few of them made up. These accept the stock Fiero hard line:

Re: Junkyard F23 transmission and engine advice.
Posted: Sun Sep 07, 2014 1:45 pm
by ericjon262
Thanks Guru, Looks like I'll be needing a .125" spacer to be where I need to be.
Re: Junkyard F23 transmission and engine advice.
Posted: Sun Sep 07, 2014 4:46 pm
by fieroguru
ericjon262 wrote:Thanks Guru, Looks like I'll be needing a .125" spacer to be where I need to be.
From your other thread asking about the stock fiero clutch finger position (2.25") and the target range for the HTOB of 2.484" to 2.557, looks to me like the spacer should be 1/4" = 2.25+ 0.25 = 2.5".
However, I wouldn't get the spacer until you get your specific clutch. There is lots of variation in clutch finger placement depending on mfg, pressure plate style, clutch disk material etc... the best approach is to get the clutch and measure it to determine the needed spacer.
Re: Junkyard F23 transmission and engine advice.
Posted: Sun Sep 07, 2014 4:52 pm
by ericjon262
fieroguru wrote:ericjon262 wrote:Thanks Guru, Looks like I'll be needing a .125" spacer to be where I need to be.
From your other thread asking about the stock fiero clutch finger position (2.25") and the target range for the HTOB of 2.484" to 2.557, looks to me like the spacer should be 1/4" = 2.25+ 0.25 = 2.5".
However, I wouldn't get the spacer until you get your specific clutch. There is lots of variation in clutch finger placement depending on mfg, pressure plate style, clutch disk material etc... the best approach is to get the clutch and measure it to determine the needed spacer.
I have my clutch, I was just curious if there was a difference in height between a fiero clutch, and an F23 spec application. My clutch is a Bully stage 4 (P/N 04-1594c) for a 2.2 application. it's a little taller then the Fiero clutch, my measurements put the fingers at about 2.4"
Re: Junkyard F23 transmission and engine advice.
Posted: Sun Sep 07, 2014 6:13 pm
by ericjon262
I've been looking all over, and I can't seem to find a part number for the axle seals, anyone got one?
Re: Junkyard F23 transmission and engine advice.
Posted: Sun Sep 07, 2014 9:53 pm
by fieroguru
Autozone # 3543
The F23 & F40 use the same axle seals as all the fiero manual transmissions.
Re: Junkyard F23 transmission and engine advice.
Posted: Sun Sep 07, 2014 10:01 pm
by ericjon262
fieroguru wrote:Autozone # 3543
The F23 & F40 use the same axle seals as all the fiero manual transmissions.
Awesome, thanks!
Re: Junkyard F23 transmission and engine advice.
Posted: Sat Nov 29, 2014 8:29 pm
by ericjon262
not that I think this is a true fix for anything, but it does offer easier clutch pedal action, and FWIW, the cavalier master is also 5/8"
Originally posted by Fiervette:
I have a recommendation for those of you with an F40 swap with the HTOB. This will probably also work for the F23 and HTOB Getrag also. The Fiero Clutch master cylinder/pedal setup has too much volume for operating the HTOB and will overextend it. When I did my V8Archie LS/F40 swap he recommend that washers be placed in between the CMC and the firewall. Although this was an adequate solution, it is definitely not elegant. So I googled Fiero CMC and found some info on a Miata forum. Miatas have a similar but smaller diameter(5/8") CMC so they use the larger Fiero (11/16") CMC to gain more fluid capacity for certain situations when their setups won't completely disengage. So I thought, why not the other way. I went to Autozone and bought a 1995 Miata Clutch master cylinder for $19.95. I would fit by slightly elongating the holes. Miata unit does not come with a push rod. I could have just ground down the end of the stock Fiero one, but instead bought a Rodney Dickman adjustable one. Be careful you get the correct one, as I got confused about Early vs Late and had to exchange for the correct one. There are Early and Late CMCs, and early and Late pedal assemblies, but the year changes for the two do not coincide. I ground down the end to fit in the Miata Piston and it bolted up and it worked. I then had to adapt the 10mm Japanese fitting on the MC to the 12mm bubble flare of the Fiero tube. I used a 12mm bubble flare connector, a 6" Tube with 3/8 on one end and 12mm bubble on the other, and finally a 10mm Japanese male to 3/8 female adapter. Perhaps it could have been done cleaner, but that was the easiest way for me.
Still, doesn't look too bad, and gets rid of the spacers. I fits well even with my S10 booster.
Benefits - No danger of overextending the HTOB, lower pedal pressure, smother engagement, cheaper and easier to find parts, no bleeding problems, and adjustable pedal height. It is now level with brake pedal.
Hopes this helps someone. Let me know if this works for someone else.
James