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Hello all! I am a huge 3rd gen enthusiast and always loved the formula 350! It is of course heart breaking knowing they never were paired with a manual transmission. So after owning my Formula 350 for years and after going through two 700r4 transmissions i figured it was time for a nice gearbox. Of course it didn't happen overnight, i had this swap in mind for almost three years, it took me that long to assemble all the parts and finally get over the fears and start this amazing swap, I WISH I STARTED SOONER! So im going to post some pictures of how it looked before the swap and after. Then ill put up a list of all the exact parts and info on my swap and of course pictures of it after all that work was done! Enjoy!!! For those wondering my car is a 1988 Firebird Formula 350 Black on Black Hardtop. Thanks For Looking!
So here is a list of the complete parts i used for my T56 Swap...
T56 Brass bearing, which was slightly greased, i refused to use the roller bearing do to many people having issues with them JUST SAYING
T56 Flywheel (resurfaced)
T56 Flywheel bolts (6 bolts)
T56 clutch and pressure disk.
T56 clutch bolts (5 bolts)
T56 bellhousing
Transmission to Bellhousing bolts (8 bolts) (reused the 700r4 bolts)
Slave cylinder spacer and bolts ( 2 Bolts)
New Crossmember for a T56 swap i got from Hawksthirdgen
I reused my 700r4 bolt to mount the T56 to the crossmember
T56 Torque arm mount ( MAKE SURE YOU HAVE THIS, NO OTHER MOUNT WILL WORK)
I reused my factory Torque arm without any modification
You will need a T5 Starter, The 350 Starter will not work. You will also need to get new bolts for the T5 starter because your 350 starter bolts will be too long. I suggest ACE Hardware, but get them where you can. Or you get a t56 LT1 starter, they are lighter and better.
I also got a metal dust shield off of ebay for my T56 and reused the (4) dust cover bolts i luckily still had from my old 700r4. (Those four bolts fit into the four holes on the bellhousing
T56 Fork and Fork T Bolt. (Thank you Hawksthirdgen) Make sure to put some grease on the T bolt as well as a little inside the fork where the T bolt connects to the fork.
T56 Transmission which i pulled from a 1997 Camaro (Side Note T56 Transmissions use Automatic Transmission fluid)
The T56 i pulled from the camaro had a bad Transmission mount bushing so i reused my old 700r4 one, it was a Energy Suspension from when i had the last Transmission rebuilt.
I reused my Stock aluminium Driveshaft, slid right into the new T56 the T56 is the same length as the 700r4 so there is no need for a new driveshaft.
Of course i had to cut out a hole in the floor tunnel for the gear shifter, the old auto shifter mount was a PAIN to remove, i used a drill bit and drilled out the tac welds.
T56 shifter dust boot
I also reused a Firebird T56 leather shifter boot becouse i liked it more that the stock T5 Boot.
I also got from ebay all the wire pigtails for the T56 and wired up my own wire harness, the pigtails were for the: Reverse Light Switch, Speedometer, and the Reverse lockout Switch. I ran that harness through the old shift cable for the 700r4, i cut the rubber plug so that the harness could fit through and it had a good seal.
Dakota Digital SGI-5 C (NEEDED!!!) If you run your car without the speedometer working for too long it will fry you ECM!! Without the Dakota Digital your car will have the check engine light on for "low or no voltage to speedometer".
I made the decision and went with the T56 style pedals, I cut off the Gas pedal and enlarged the top hole that way i could screw in the bolt up top, you will also need to enlarge the two bottom holes on the T56 pedals. I unfortunately could not find T5 pedal set which i could have used the braces for the firewall i did find a T5 U bolt that mounts the slave to the firewall which i recommend using instead of standard bolts, the U shape fits the T56 slave and helps reduce firewall flex, i did have an issue with firewall flex so i made a brace out of pipe which cured my flex SEE PICTURE.
I also reused my stock brake switch, ( It threads right into the T56 pedal set), I also reused my Cruise control switch and wired it into my T56 pedal set in conjunction with the T56 cruise control switch for the clutch pedal. So for the record yes my cruise control works and cuts off if i hit the pedals!!! I used the T56 Neutral safety switch also.
For the Reverse lockout switch i wired it to a toggle switch which i mounted to the PCM connector under the drivers side dash, so if i need to go in reverse i flip that toggle switch, REVERSE then flip it back, IF I DONT FLIP IT BACK IT WILL GO INTO REVERSE IF IM MOVING FOWARD it has not happened yet but i made it a habit to always flip the switch back so it locks out reverse SEE PICTURE.
T56 Hurst shifter ****
T56 short throw shifter lever (hawks)
Used T5 Shifter Plate which i made sure to find authentic, I Swapped in a Hawks Six gear indicator which was a nice finishing touch SEE PICTURE.
Now for the slave cylinder i went with a GM authentic part, I would suggest not going with any other manufacturer but GM due to fitment issues ive heard JUST SAYING.
When you go to mount the slave cylinder you will need to remove the brake booster completely and just push the brake reservoir assembly gently out of the way, THIS IS THE ONLY WAY THAT SLAVE CYLINDER WILL FIT DOWN PAST THE ENGINE TRUST ME, IT WILL SAVE TIME SO REMOVE THE BRAKE BOOSTER IT WILL MAKE EVERYTHING EASIER. Side note if you have the pedals installed and are installing the slave cylinder do not put the slave shaft onto the clutch pedal because if you accidentally push down on the pedal you will bust your 200+ dollar slave cylinder!
I also tracked down a factory T5 slave cylinder reservoir mount for the new T56 so it could be mounted next to the brake booster just like on stock T5, The T56 reservoir mounted up perfectly with the mount! SEE PICTURE.
This swap took me and a buddy about 5 days to accomplish, YEAH i hear it could be done in a weekend but i didn't rush this swap and made sure to take my time. Everything works like it should, i have no check engine light on, my speedo works, as well as my brake lights and reverse lights as well as my Cruise control which is really neat this Bird now has about 60 thousand miles on it. I have alot more fun with this car and its a joy to drive i would recommend this swap to anyone who is willing to attempt it. This swap was intended to look like it came from the factory which i think i accomplished!
IF anyone has any questions please PM me ill be glad to help ill try to go into more detail on specific areas of my swap!!!
Ok with some of the wiring for the Speedo there is a good video on Youtube called "How to wire a Speedometer to a Non-Stock transmission". This video is nice but it shows how to wire a speedo to work with a LS motor. I have the stock 350 TPI motor so it wont work for my application. In the picture i attached is how the wiring is on my car and it works perfectly with no check engine light. The wires that come from the Speedo sensor at the tail shaft on the T56 is complelty wrapped in tin foil and the tin foil is grounded inside the car, (see the green wire coming out and going to the right?) i grounded that to a existing ground spot next to the kicker panel. The only reason for the tin foil is to help with interference. For most of the wiring of the Dakota Digital you will use all the wires that connect into the VSS Buffer. You will not use the Yellow and Purple which have a separate connector, so dont cut those wires just unconnect it and leave it hanging. In the picture of the Dakota Digital you will see a SENSOR GROUND and a INPUT, those are the only two spots you will use the two wires that come from the sensor at the T56 tail shaft. Plug 2 for SENSOR GROUND and plug 1 for INPUT. Simple. As far as calibrating i have the switch in the OFF position for 1 and 2, then ON for 3 and 4 See picture. you may need to use the up and down switch to either lower or raise vehicle speed. When i did mine i drove by a speed sign that displayed my speed and i adjusted from there.
I took the best picture i could of the pedals and its wiring. I reused the brake switch i had as well as the cruise control switch, they thread right into the T56 pedals like a factory fit. Everything fit well and it was nice not needing to be under the dash having to rewire everything which would have been a huge PAIN. The Neutral safety switch is the stock T56 one that came with the pedals, you just wire those into the purple and yellow wires that connected into your AUTO shifter, you will know what im talking about when you remove you Auto shifter, Connect YELLOW TO YELLOW AND PURPLE TO PURPLE. Now for the reverse lights there are two wires that connect into the light switch on the passenger side of the transmission. Use the same diagram as the Speedo sensor, use plug 2 for the green wire and plug 1 for the blue wire. The orange and black wire you do not use just cap those. The reverse lock out i wired to a simple toggle switch. I hope that helps Thanks For Looking!!!
I used an Lt1 starter with a lifetime warranty from Autozone. It's much smaller than the stock starter and was pretty cheap. Just an FYI for future swappers. I used it when my car was a 700R4, and had no issues with it when I swapped to to the T56.
Any specific year starter? Or just ask for a LT1 starter for 1994/95 Camaro/Firebird?
There are a couple LT1 Fbody starters. The LT1 Caprice got them too. They are perm. magnet, lighter, smaller than the smaller 305 starter. No reason to go LB9 305 starter unless you have one already. The late 80s and 90s vette starter is nice too but less common.
Yeah i just bought a 1988 305 t5 starter at autozone just because it was actually way cheaper than a lt1 starter. i think i payed 89 dollars for the t5 starter and the lt1 was like 160. It works fine for me with no problems only issue was that i had to get new bolts lol
I didn't experience that problem myself, I've heard that from a few people that ran their cars without a working speedometer after the swap. The ecm needs a signal from the speedometer to determine fuel mixture i believe. maybe someone else can chime in that knows more.
10-26-2015, 07:29 PM
the T56 is the same length as the 700r4 so there is no need for a new driveshaft. 
I used the T56 Neutral safety switch also.
Side note if you have the pedals installed and are installing the slave cylinder do not put the slave shaft onto the clutch pedal because if you accidentally push down on the pedal you will bust your 200+ dollar slave cylinder!
Fits all bellhousings. 
