I have a iron block 402ci motor and recently head some work done on one of my heads. I am prepping my block to reinstall the head and noticed one of the dowels at the bottom front and rear head stud is missing. Well I go to my parts dealer and get a new GM Head Dowel Part # 12570326. Well now looking at the two dowels the new one is roughly a 1/4" taller than the one I had. The new one is also bright silver metal and the other is a dark metal roughly the same color as my ARP head studs. I guess my question is is the taller dowel going to cause me any problems? I know I need to set the head in place and see if it clears but I wanted to ask you guys 1st to see if anyone else has had a similar issue.

I have looked online to see if the iron motors may use a shorter dowel but it looks like GM has one universal part which confuses me even more. The only issue I could see is if the iron block may have a shallower depth for the dowel which may push up on the head once I lay it down not allowing it to seal.

Thanks guys

 

I found a document that says that dowel should 0.590 inch tall, which you probably already know. i doubt that it will create interference, but you could measure the two holes and make sure that their combined depths exceed the 0.590 inch parameter.

Supplement - I also found an LS1 dowel that has identical dimensions except it is only 0.494 inch tall and is part number 12558081.

http://www.enginepartsplus.com/EPP_CATALOG_2010.pdf

 

I know when I pulled my heads of a few times and sat them face down the towel had enough space to slide up into the head and sit flush with the mating surface....so you should be fine