All I can say it the group of engineers that designed the SB 400 should be grouped up and dunked in $hit.

With that said I just swapped on my Brodix Track 1 heads, ran the torque pattern once at 40 ft/lbs, then when I started round 2 at 70 ft/lbs the nightmare began, yep, the threads pulled out of the block. :mad: :mad:

I helicoiled it, started the pattern again and another one stripped, and no its not the torque wrench.... this continued over and over again and I now have 15 out of of the 17 bolts with helicoils installed. My machinist is not concerned about this what do you all think about running all helicoiled head bolts?

Thanks...

Mark that is a bunch of shit - those are what 1/2 13 thread right? running a heli coil should not cause major problems unless the heli is not below the block surface not tring to say you would not leave these high - and also seal the shit out the theads - and your just going to have to go with it and be a test guy for us- or go all out and go studs - good luck - Jess did you get your front line back? :D

Jess,

They are 7/16"-14 and it just got better, I guess my tap got bent or worn or something and the last two holes I tapped are crooked, found this out after I started the threads about 1 turn in put the wrench on them, felt a little resistance and then I heard a creak, that was when the helicoil cross threaded... now we are making a set of 5/8" inserts with 7/16" threads... Man this simple head swap is becoming a PITA....

And the front shaft came in today, have not had time to pull it out of the tube..

Thanks

Have you checked how far the bolts go into the block?

With aftermarket heads, especially ones with heavily revised ports or rocker-mount pads, it's not uncommon to need a different length bolt. Also double-check to be sure you didn't get a set of metric bolts or got the wrong thread.

The threads should go an inch or so into the block before they start to tighten down.

Or, as recommended above, get a stud kit.

Doc.

Doc, I have about 3/4-7/8 engagement into the block, one head went down fine but the other has been a real pain!

Thanks for the advice, looks like the 30 year old block has past its prime... :D