For those of you who put 354 heads on your 331. What did you do about the locating pins? The holes in the heads are smaller than the pin diameter. If I open them up, will I get into the water jacket? If I open them up, how much tollerance do I want on the hole for the pin? If I have new pins made, how the heck do I get the old ones out??
A pair of vice grips , twist them a few time & then smack the grips with a hammer a couple of times usually does it. The pins are close enough to the edge of the block that you can get close enough to drive the vice grips up. I don't know for sure about opening the hole up--probably you would be ok. A stepped pin would be a cinch to make using a piece of drill rod, probably could make it using a drill press & a dremel .
The machinist here at work will make me up some pins, no problem. Just have to tell him what I need. Do they need to be hardened or is stainless good enough? How tight to these need to be???
they should be hardened if at all possible, and a "good" tolerance would be -.005 to -.007 total clearance (-.0025 to -.0035 per pin undersize) to allow the heads to be able to slip over them...stepped pins I believe are sold by Hot Heads...I was planning on grinding my own at work if I ever find the damned 354 heads...
Thanks man! I'll see what HHH has before I bug my machinist. Man, just one more reason I need a lathe at home!!
Here's some, but I'm not sure if they will work. If they will, $2.60 is a better idea than bugging my machinist... http://www.hothemiheads.com/cylinder_heads/head_dowel_pins.html
Those pins are not what you need... They are intended for putting the earlier heads on a later block - not later heads onto an earlier block.
Yeah, that's how it's looking. I contacted HHH about rather or not they have the correct pins for what I need. Haven't heard back yet.
a lathe won't do you any good making these pins, they will need to be ground to size and the metal is much too hard to cut with conventional lathe tools...it wouldn't take much time for a machinist to take some out of the box hardened steel dowels, grind them to size and they're done...
Just got word from Bob Walker. He said for my application ('56 and later, mine are 57-58 truck/industrial/marine 354) his straight pin #21204 is what I need at $1.00 each.
If Bob is correct, then I guess not. I was told that the pins for the early 331 extended bell are stepped OUT for the heads. Smaller in the block and bigger for the head. I guess the hole in the heads must be the same as the holes in the block then. Does anyone have an early 331 block apart and some precision calipers they could measure the holes in the block?? Hopefully Jimmy will ring in here. He's running Industrial heads on his extended bell 331 also. Not sure if they're different from mine or not though.
don't you hate when they finaly get the info they need and don't take the time to post the results to share
Well, that explains something anyway - maybe. I have a 331 mocked up and had a 354 head layin nearby and tried to stick it on the block to show somebody how wide these things can be and it wouldn't set down. So the 331 dowl is larger than the 354? Interesting. But the 354/392 are the same?
The answer was, yes. Stepped pins are available. Sorry for not updating this thread. I'm pretty sure it was covered in the Tech Index, and was letting an old thread die. But, it's still a good topic, since this is done quite a bit. Pull the pins out (this can get tricky) and insert appropriate stepped pins. Some of the pins can be accessed from behind, some cannot. The ones that cannot may require a bit of work, if they're frozen in there pretty good. I believe I ended up drilling one out, but it went into the water jacket and was accessible through a water pump port so I could vacuum any metal out. Stuck a greased paper towel up in behind the pin that was getting drilled to catch as much as possible.
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