Hi will t5 from 84 z28 with 3.73 fit 91 z28 with 700 R4 fit? Plan on get flywheel and clutch kit 84 is l69 91 is lb9 both 305 did I leave anything out?

You will need 1991 flywheel and compatible VSS.

And 1984 flex plate and 700-R4 driven speedo gear.

Just get everything from a 91 the trans will bolt right up but the 91 is a roller cam so different flywheel and such. Other than that just get some pedals and cut some holes.

thanks For your help , the T5 From 84 z28 IS going in the 91 z28 with TPI that has a Rear main seal 1-piece the 84 is 2-piece Rear main Seal Do I need an Adapter?
I m also going to swap rears the 84 is Disc Brakes Rear and 3.73.
I need 84 Flex plate and 91 Flywheel ? will I still need the 700R4 driven Speedo gear?

the 84 Rear Disc Brakes should work with the 91 Brake Booster ?

Did you drill holes through the pedals and going the paint it?

I guessing 84 was cable drive so this would work.
http://tpiparts.net/inc/sdetail/7587

If your retaining the tpi you should have your memcal reprogrammed for a manual transmission.

Yes. The 82-85 V8 third gen flex plate will work with the transmission converter bolts, but it boots to the older engine crank, and is balanced correctly for the 84. No adapter, just the right parts.

The boosters shouldn't need changed; bolt pattern at the master and at firewall is the same. Bias front to rear needs changed; ask on the brakes forum on here.

Tune perf. posted the VSS you'll need for the 91. It will convert the 84 speedo drive to VSS output. The speedo gears in the T5 won't need changed since you're keeping the 3.73 gears with it. And yes, absolutely get a manual tune chip / PROM / mem cal so it drives correctly.

This thread makes my head hurt.

#1 The T5 from an 84 is a non-worldclass T5. It's a somewhat weaker T5 than what would have come in a 91.

#2 The flywheel on 86-92 cars is different than 82-85, because the 1pc rear main seal crankshaft has a different bolt pattern. Get a flywheel, clutch set, for a 91 from the parts store.

Other thoughts... 84 pedals will bolt in a 91, but the clutch safety switch is a different design than what they used in 91. GM changed to the later switch around 86 or 87. As mentioned the VSS on a 91 is electronic, and the OEM 5spd VSS is extinct. Also take a good look at the torque arm mount. There are two versions, one with lips towards the driveshaft, the other faces away, if the mount doesn't match your car you'll have to use the torque arm from the 84, or find a different mount.

Re: The rear axle... The 84 disc brakes are the Delco-Moraine steel calipers. The ones that work so poorly that they were recalled. GM developed solutions that worked so well that by 1989 they decided to just buy a better rear brake system from PBR. If your drums are functional, they'll stop better than Delco-Moraine discs. As far as the drum/disc brake system working with the Delco-Moraine rear discs - Maybe, but probably not well. In 84 a rear disc car had a different master cylinder and prop valve than a drum/disc car. Also, 84 used different brake line fittings than a 91, so pretty much nothing is just going to swap over.

The 84 rear might be a limited slip, but it could be a Gov-lock. I'd pull the cover and verify, if it's a Gov-lock I wouldn't bother with it. For that matter even if it's an Auburn it's probably not any good. Also weaker axles...

There just isn't much really in common between an 84 and a 91. The 84 makes a poor parts donor since almost everything on the 91 is an upgrade over the earlier car.

I just installed an rebuilt 700r4 and now every gear is in drive expect park.