Hi, Can anyone tell me what the S1 means...(stage one?). Also what do the other letters & numbers mean? Thanks for any help, Joe
The "S1" cast into the head indicates a service replacement. There's no way to know what valve size you have by looking at casting numbers without inspection, as all the Stage 1 and standard heads received the machining and valves after the casting process. The 1231786 indicates a 1970 455 head, which is interesting since they oil the rockers through the pushrods, while your rocker arms were designed to oil through the cylinder head. It would be interesting to know more about the parts you have there and which oiling method is being used. Devon
Hi <st1lace w:st="on">Devon</st1lace><o></o> I have aluminum rocker arms so Im guessing the oil is not coming threw the pushrods. One of my rockers just broke & was thinking of switching to the steel rocker arms with the pushrods that has the oil going threw them is that possible.<o></o>
I'm wondering if your service replacement head (or heads) are drilled for oiling like the '69 and earlier heads. Unbolt the rocker shaft and lets see what the rocker pedestals and pushrods look like. Devon
Sorry it so long but took off the shaft & looks to be oiled by the pushrods? what do you think.also this is a 430 block thanks Joe
This is getting interesting. If it's a 400 or 430 block, the hole you see drilled next to the rocker hold down bolt hole on the pedestal pictured to the left is how your 400/430 rockers get their oil. For some reason, you have 5/16" hollow pushrods used on the 455s, which if using 455 lifters, are ALSO supplying oil to the rockers. Even if you have the correct 400/430 lifters that don't allow oil to the pushrods, the ends of the pushrods are the wrong size for your rockers. The 400/430 rockers are designed to receive a pushrod with a 3/8" ball on the end. Devon
can that be why the rocker arm have that ware on themlike they are hitting the valve spring. The other head is a 1384720 which is a 68 400/430 from what i can gather.:ball:
Hard to say, seems doubtful. I'd think the mismatch issue would most likely show up as improper wear on the tip of the pushrod and the inside of the rocker cup. Devon
In your opinion what do you think I should do just put new aluminum rocker arms & new shafts on & leave it like the other guy had it or remove the heads? I have a basic knowledge of engines removing the heads is a little more then I could handle so I would have to get someone to help. If I leave it like it was do you think Im going to blow up the engine.<o></o> Thanks for the help <o></o> Joe<o></o>
Glad to help. If it were me, the first thing I'd do is pull the distributor and run the oil pump with an electric drill. If you get oil from front rocker pedestal but not the pushrods, just replace the hollow pushrods with correct solid 400/430 pieces and either replace the broken rocker arm or install a new/used 400/430 rocker assembly. If you are getting oil from the pushrods, install hybrid solid pushrods from TA Performance. "Hybrid" means a 5/16" diameter ball on the lifter end, a 3/8" ball on the rocker end. You need the hybrid because the 455 lifters want to see the 5/16" ball. Oil from the pushrods means the later style lifters are in place. Lastly, if you are getting oil from the pushrods, you can also elect to block the oil hole in the pedestal and install a 455 rocker assembly. You'll need to inspect the existing hollow pushrods for wear before reusing them. The bottom line is you want to take care of two things: (1) make sure the rockers are getting oil from one method or the other, not both. (2) make sure your pushrods are compatible size-wise with the existing lifters and the choice of rocker assembly. Devon
Thanks <st1lace w:st="on">Devon</st1lace> you have been very helpful I’m going to pull distributor & go from there.<o></o> Thanks again for all the help ill let you know how it turns out. :TU:<o></o> Joe<o></o>
