I used to work for Aamco and I have done hundreds of GM clutches.
Until I did a LT1 I don't remember ever seeing a GM flywheel for V8 cars or trucks that DID NOT HAVE PRESSURE PLATE DOWELS. I know that LT1's dont have dowels! I know they don't need them because of the special pressure plate and special pressure plate bolts they used!

Now my question is; do 87 and up (1 pc rear main) Camaros and Firebirds with V8's (T-5) have flywheels that didnt use the two or three little pressure plate locating dowels? I just can't remember.

I'm talking ONLY about the T-5 1 piece rear main seal cars. I am NOT curious about the 2 piece rear main ones, I know they had them, I am NOT curious about the V6's either. Just the V8 1 piece rear main (87-up?) cars.
If it turns out that they didnt have dowels and were never meant to have them can someone post a picture of the flywheel? The clutch? Are there even holes for the dowels on the flywheel or clutch? Does anyone have a picture of either this flywheel or clutch?

 

I've never seen a GM V8 with clutch dowel pins. Granted I've only been doing this and driving 4-speeds and lately 5-speeds for ..... well let's just say a real long time, but that's alot of clutches I've seen in my day with no dowel pins.

I have a 1-piece flywheel laying around that doesn't have them; along with 2-piece flywheels from every kind of Chevrolet from 69 Chevelle big block cars to various trucks to the ones I use on my 83 car, and none of them have dowel pins either. None of the Z28s or other cars I had back in the 70s had them either.

Pressure plate bolts are special bolts, with a shoulder that acts as a dowel pin, by fitting tight to both the hole in the flywheel and the clutch; the bolt holes in the flywheel have the threads recessed about 1/4" to give room for the shoulder.

 

like this

 

no the t-5 ones (1pc) don't use dowels. I won't say how many others don't either as you only asked about the 1pc w/t-5

 

never seen a dowel for the preasure plate on a gm

 

ive never seen one on a GM flywheel either

 

gee I guess theres a first time for everything, scroll up and look at the aluminum one from fidanza for 1 pc rear main seal gm vehicles

 

pretty sure we're talkin OEM here....fidanza is anything but

 

yeah but they build them to take stock clutches or you they wouldnt work

 

maybe, but i dont recall any of my clutches having holes for the dowels either

 

ive never seen dowels on a GM one at all...


that doesnt mean the holes for the dowels on the pressure plate arnt there though.....

 

the holes are there but, no dowels

 

My flywheel for my truck has dowels 1PRMS 88 block. The flywheel came from a 90+ 5 speed. Ive seen some that have them some that dont, most cars dont have them, I know the setup in the firebird 1prm doesent have them the car that I got my components from got it's drivetrain from an 89.

 

thanks you ssc. your answer has helped me solve the mystery. its truck versus car.