5 speed swap

[whiteretta]

I swear there was a write up on this, but I went through multiple pages of information on here, and could not find one. Am I blind, or do we not have one?

[woody90gtz]

Geoff had a half-finished write-up about 15 years ago...give him a shout.

[whiteretta]

Geoff had a half-finished write-up about 15 years ago...give him a shout.

I'll have to do that, I'm not quite ready to do the swap yet, but I am in the process of getting parts ordered, just not 100% on what all I will need!

[Rettax3]

I had a write-up back on bstuff waaay back when, though there were a few differences as the conversion was going into the GTU with the 3800SC swap.
Partly depends on which variant of the 5-speed you are going with. Oldest ones used an enclosed jackshaft and both CV axles were the same, left and right. By 1990, GM recast the bell-housing to bring the clutch-fork turnbuckle fully internal, and ditched the big aluminum jackshaft housing, relocated the right output shaft oil-seal into the differential case (though the three threaded mounting holes for the housing remained, at least for a while), and used different CV axles left to right, so definitely try to catch the year of the donor. Beware other makes as donors, like older Cavaliers and Fieros, as they typically used a different and entirely incompatible VSS in the transaxle...

But until Geoff chimes in, here is a full list -someone can add in anything I've missed: (Items marked * should be readily available aftermarket new.)
-5-speed Transaxle -assuming a Muncie/Getrag 282...
-Transaxle Mount. Being a '94, I'm not sure which parts differ from manual to automatic off-hand, in the older "MPFI" 2.8 and 3.1 era, the mount was on top of the transaxle instead of next to it, and the mounting plates were different automatic vs manual, and the right-side engine-mount bracket was also different automatic vs manual, as the TH125C auto spaced a little different front-to-back compared to the M/G-282, so they shifted the engine to retain optimal CV Axle angle. You may also want to verify the engine-mount you are using on your 3500 is positioned correctly for the manual.
-Jackshaft (also called Intermediate Shaft) and Housing, if applicable.
-Left CV Axle.*
-Right CV Axle.*
-Flywheel (I don't believe you need to worry about the 'balance' on your 3500, again someone correct me if I'm wrong, but I believe both the 3.1 MPFI and the 3500 are internally balanced).*
-Clutch kit.*
-2x Shifter Cables -this will be the hard part to source good ones.
-Shift-Cable Firewall Bushing (thick rhombus-shaped rubber 'block' that the shifter cables go through -you can drill a second hole in the one you already have for your automatic shifter-cable, or use one from the donor car -the stamped metal cover-plate will probably need to be modified or replaced for the second cable as well).
-Shifter Assembly -a similar-era "N" Body, such as Grand Am, Achieva, Skylark, are very similar, and should bolt-in, and even offer a more robust shifter-arm with a threaded round shaft vs the Beretta's cheap-ass stamped shifter-arm, just as a sourcing option -my second '95 Z-26 five-speed swap has one of those, but the center console is missing a mounting bracket because of this -something that is still on the to-do list...
-Console Shift-Plate and Boot (or modify your automatic one. For posterity, I'll mention these are different for the '91 and up models than for the '90 and older versions, though you already know that. Nice if you can get one with the trunk-release button too).
-Clutch Pedal Assembly -Mounting Bracket, Arm and Pedal -good time to check the bushings and clean/lubricate as necessary.
-Brake Pedal Arm/Pedal, or cut-down your automatic Brake Pedal and replace the Pad. I've gone both routes in the past.
-Clutch Slave Cylinder (match this up to the donor transaxle year if possible -there were a couple of different styles, but the older ones are nice in that they have a bleeder-screw on the slave and typically a heavier-duty construction).*
-Clutch Master Cylinder (match this up to the Slave-Cylinder year -I don't think GM changed the piston diameter at any point, but...).*
-Clutch Master Cylinder Reservoir, Cap, and Line (doubt you will find this aftermarket for the application, but really anything you can fit in and bolt in place above the Master Cylinder should work, the Line just needs to be a Brake Fluid-compatible rubber hose).
-Clutch Hydraulic Line (another hard-to-find part, these were originally plastic crap, some years utilized a two-piece design with a self-sealing quick-disconnect and apparently a flow restrictor that inhibits harsh clutch engagement -and burnouts-. My '90 Turbo T-Type 'Retta STILL has the 'temporary' copper tubing hack-job I soldered up for it... Maybe 15 years ago? And on the '95 Turbo Quad-Cam Z, I used a cleaner 3/16" steel brake-line flared to JIC 37-degree standard flare with AN (Army/Navy) adapters from Summit or Jegs (I believe these were for a Camaro T-56 application but plug into the hydraulic cylinders properly), and AN flare nuts/sleeves -both JIC and AN flare are 37 degrees and are essentially compatible in regards to this application, but beware the common 45-degree flare if building your own hydraulic line, you even need the different flaring tool).
-Synchromesh manual transmission fluid is called for, but I know at least a couple community members just ran 10W30 motor oil without problems... That said Synchromesh is cheap, I personally keep a case on the shelf.*
-DOT 3 or 4 Brake Fluid (hey, I said FULL list! ).*

-You will need to drill the three holes in the firewall for the clutch Master Cylinder/clutch-pedal mounting studs -three holes in all, 2x10mm and one for the Master that is ~1.125"? A correctly-sized hole-saw or sheetmetal knock-out tool will be needed for this... You should see the 'template' under the dash behind the carpet, where the holes are pre-drilled in the innermost layer of firewall sheetmetal -I didn't know that when I did the conversion on my 3800 GTU back when and made my own template off the brake master-cylinder mounting holes, but drilling outward from under the dash is easier.
-Gasket-Seal or RTV Silicon to seal the firewall at the Master Cylinder and the three holes you just drilled. Don't think the gaskets are still available, but you could cut your own if RTV is distasteful to you.
-I would also recommend brushing on a little paint on those three holes to prevent rust from starting up there.
-You may have to retune your PCM, especially the Idle Follow values -Woody may offer some suggestions on this, he is far more knowledgeable on this than I am.

Let me know if you need an extra set of 'eyes' on your parts-list, or any tips during the install itself, I'll help out if I can. I've done these swaps a few times already, with another one or two waiting in the wings. You are welcome to PM me too, if you need a timely response -I don't check the Board as often as my e-mail, so...

[woody90gtz]

You can also use a premade -3AN braided brake hose for the clutch line with the AN adapters. I'd call this a MUST if you want to have fun being stupid. I glazed a clutch in one day drag racing with the stock hose and then went 10+yrs pounding on it with zero problems with the braided line.

Tune with a 94 I actually haven't done. Jay is running a 3400 manual with the obd1.5 computer though, so he should be able to point you in the right direction there.

There are 3 style pass axles too. One was the enclosed jackshaft and one was the long axle shaft as mentioned. Mine had the exposed jackshaft with a bracket on the front (or crank pulley side near firewall) of the block and equal length axles. Rumor is the short and long axles give you torque steer, but I've never confirmed or denied that.

You can also just cut a hole in your shift plate for the trunk release if needed. Easy with a drill and then file.