70 z rocker arm #'s

[03C 70 z]

Looking for OE rockers for my 1970 z. Does anyone know a part # for these? Upon engine disassembly, 8 rockers had "T" stamped on top. Read somewhere that was heat treated tip. If that is the case, I am looking for 8 more but need to verify a part #. Someone told me 3974290 is the # but upon further research it does not seem right.

[Salvatore]

I am sure the "O" rockers are good to use. I would put the Crane or Comp Cams roller tip rockers on with the polylocks anyway. JMO Sam

[03C 70 z]

Do you know the GM part # for the "O" rocker?

[JRSully]

Use the roller tips like Sammy says, factory arms are garbage for the most part and you wouldn't want to ruin a recently rebuilt, possibly original engine to a cheap stamped steel rocker arm, especially if you are going to "air it out" My .02

[Salvatore]

I don't have the part number at my finger tips. I think that the "O" is the only number on the rocker. If it does not have an "O" on the rocker its not what you want for originality. Put the roller tips on. Its not worth buying NOS "O" rockers in my opinion. Manley, I believe also makes a real good standard rocker arm for the 302/LT-1.

[DarrenX33]

When I did my motor a few years back (it's that long ago? ) I used the Crane stamped steel roller rockers.

For some reason I am thinking that later on the O stamp was replaced with a "V" or an arrow of some sort to note hi-perf? Anyone else smoking what I am?

[Mr70]

The "O" rocker is part #3843359,used on ALL late 60's to 1970 assembled small blocks,in ALL vehicles.
The "V" rocker is part #3974290,that later superceded it with the start of 1971 production,well into 1980's.
I have one NOS "O" rocker here with 3359 on the adhesive tag only.

[COPO 70 RS/Z28]

Mine are all O stamped ???????????