head bolt question again....

93project

Active Member
Apr 21, 2009
549
52
38
El Paso, tx
Hey guys,

I just installed a set of aluminum Edelbrock Performers on a 331 block using 154-3601. These bolts were recommeded for use with edelbrock heads. I didnt use and spacers/bushings... just the washers that came with the bolts. Will this be ok? I went to a shop today and he was putting the same heads on and he used the edelbrock bushings AND the Arp washers! This seemed wrong to me since the bolts now sat a few mm's higher that they normally would. I kept thinking this would cause weakened clamping force since the bolts were threaded all the way in. What do you guys think? Do i need to pull the heads off and re do with bushings? I hope not. The locating dowels were in place and the bolts torqued down to 80 and 73 ft lbs just fine. I used to have iron GT40 on like this with no problems over 5 yrs running like that.
Thanks! :nice::hail2:
 
Those are the same 154-3601 bolts and heads I have. You're supposed to use those bolts with the stepped bushings otherwise the only thing keeping the head from shifting are the flimsy block dowels. It's also possible for the washers to "oilcan," sink into the head, and relax torque on the bolts.

The jury seems to be out whether the flat washers are necessary with the bushings. I installed mine without the flat washer and there have been no problems in ~25,000mi thus far. It certainly won't hurt to use both.
 
If it's any consolation, I ended up in a similar situation with the same engine when I tried to get by with PAW's house-brand grade 8 head bolts. I found out the hard way that they were made offshore and the manufacturer cheated on the metallurgy. End result was a couple breaking around 60ft-lbs, so I had to get ARP bolts and new head gaskets too.