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Can anybody tell me what the typical length of a short head bolt for a small block Chevy is? I did an aluminum head swap on a 350, using Edelbrock heads, some new bolts with washers, and ARP thread sealer. I normally use ARP bolts, but I thought I would try these from Jegs. Look the same and made in the USA. After getting everything back together, a few of the outer head bolts were seeping coolant. I've used their sealant before and never had this issue, but it was always cast iron heads. Anyway, I decided to pull out one bolt at a time and re-torque, using a different sealer. Got through one head without any problems. Went to the passenger side head and the third outer bolt from the back pulled the threads out of the block right before I hit 65 ft/lbs. These short bolts measure 1 3/4" without a washer. The stock short bolts I have average 1 3/4" too, with the exception of a couple which are slightly shorter. Add a washer and you're down to 1 5/8". I'm just concerned I'm not getting enough thread engagement in the hole.
 

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Well since you have to pull the head off anyway now to fix the threads, flip the head over and see how much the bolt protrudes past the head. I would guess it was not the bolt length and more that many old GM blocks have the threads rotted out of the holes. I have seen it many times working in the machine shop that generally the ones at the ends and along the bottom of the deck are the most susceptible to this and require helicoils.
 
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