I just got an LT1 T56 (i'm pretty sure) I don't know the year though but i know its not a 93 and i did get the flywheel/clutch and the hydraulics off of it, as well as the B&M ripper shifter

the input shaft measured 5 5/8 (i probably did a bad job measuring)
I tested the hydraulics via me pulling the arm away from the transmission and my friend pushed the shaft on the master in, it pulled me towards the transmission fairly easily (so sounds like an LT t56 right? the bell housing looks right)

I have a 2pc RMS 71 vette 350 and i was looking at flywheels on another post
i'm thinking the 13.5 lb flywheels are a bit too light? Is anyone using it having idle problems? I'm planning on tuning it (swapping to an 86-89 computer, I have an 85) but i do want a light flywheel and i'm wondering if the RAM one may be a better choice

I'm planning on getting 3rd gen pedals and modifying the master cylinder shaft
where should i cut it before i thread it?

I was also planning on getting a 4th gen drive shaft from the junkyard (usually a v6 camaro in there somewhere) will that work with the t56 and my 9 bolt?

I don't have a yolk so will a stock LT one be fine?

Also I like my stock speedometer I was wondering who still makes a cable swap?

 

If the 350 is going to get rebuilt, just get an 86 or newer 350 and save money on the flywheel. 87-up has easy roller cam provisions too.

4th gen driveshafts aren't stronger and they are in some cases, shorter. No gain there.

Every third and 4th gen uses a 27 spline yoke except for the third gen Firehawks.

 

Ok I'll just use the Yolk from the 700R4 if I don't need a specific one

 

All the yokes are the same, so dont stress it. 3rd gen and 4th gen driveshafts are generally the same length. I am surprised to hear anyone say some of them are shorter... thats a little weird. But a lot of guys (including myself) have 4th gen aluminum driveshafts in their cars. Swapped right out with my 3rd gen driveshaft.

 

Thanks for the info on the drive shaft, they are 50$ from my local yard

 

actually it was 30$, I didn't find an aluminum one so i got another steel one from a 3.8, it actually happens to be heavier and larger diameter than my original drive shaft, its also maybe 1/4 inch shorter.

my 71 engine happened to already have a 153 tooth flexplate/starter but i had to make a little space in the bell housing for the larger old style starter.

I replaced the fluid in my trans, only two quarts of black fluid came out... I poured around 3.5 qts back in before fluid started draining back out of the fill hole.
But i have a terrible sounding grinding noise at idle/light load coming from the front of the trans in gear or not.

I ended up with 4th gen pedals, a new clutch kit, new pilot bushing and a new master/slave assembly...
in 6th gear around 1200rpm (tires off the ground) i don't have the vibrations i use to get from my old drive shaft (anything over 65) so thats pretty good
but its actually very hard to spin the engine from my wheels with the trans in 6th, and even with the tires off the ground i needed to give it a little power to keep the car going with it in 6th which is really surprising to me