67 twin turbo dart

[AUSA66]

Could it be working the bolt side to side in the load unload cycle there doesn't appears to be a lot of surface area on the retainer post

 

[Matts440]

Pardon my ignorance, I've only dealt with B/RB engines. Why is there a hole in the head of the bolt that goes down the shaft? The allen headed bolts that I'm use to only have a hole in the head part. With all the material missing in the shaft of the bolt it will be weaker than a bolt with no hole.


View attachment 1716492088

Those pieces are for the shaft mount they came up with instead of a stud mount like a Chevy for the magnum heads so it links the rocker arms together per cylinder

 

[Matts440]

Here's what they look like and where those go

 

[AUSA66]

may be possible to put a heavy brace place across the top to stop movement

 

[Matts440]

may be possible to put a heavy brace place across the top to stop movement

Not sure without getting in the way of the rockers movement. Was thinking if studs would be better but again most of ARP nuts are wider than a Allen head top

 

[AUSA66]

ARP 3/8" unc with a UNF top stud, ARP do a small diameter 12 point nut if the nut has to big a diameter just put the stud in the drill with the nut & file it down slightly also you can make sure the stud is all the way in the head & not put out

 

[Matts440]

The head has inserts into to adapt to this set up. I'm just wondering if with studs and tightening if it would pull the inserts out. I believe the bolts are 5/16".

 

[RustyRatRod]

Here's what they look like and where those go

View attachment 1716492119

View attachment 1716492120

It appears from the witness marks under the bolt heads that something's moving around. ...that shouldn't be.

 

[AUSA66]

If they pull out then the inserts are not deep enough i use 5/16" with about 3/4" of thread in the head.

If the put out at the torque setting then they will definitely pull out under full spring pressure.

 

[AUSA66]

Another question is why are the spacers curved they should be flat so they mate across they whole surface of the holdown by the looks of the witness marks they are only touching the bar on the ends of the curve also they should be hardened under repetitive action the bright steel will compress & you will lose tension.All the pressure should be on the machined flat surface of the bar not the curved you will never get a good match put some marked on the end & tighten down remove & see what sort of contact you are getting

 

[Matts440]

Another question is why are the spacers curved they should be flat so they mate across they whole surface of the holdown by the looks of the witness marks they are only touching the bar on the ends of the curve also they should be hardened under repetitive action the bright steel will compress & you will lose tension.All the pressure should be on the machined flat surface of the bar not the curved you will never get a good match put some marked on the end & tighten down remove & see what sort of contact you are getting

The curve part sits on the shaft to act like a cradle for it, the flat part goes to the head. There's a small shim underneath to correct geometry. The shoulder is long enough to get through the shaft only and the thread part is through the pedestals. I wonder if this is one that I removed due to the locks broke and installed back on and maybe forgot to torque them down but im pretty sure I did. Not sure. This is why im replacing all the bolts and torquing them all down to spec. Hughes said I was the first the break one lol yay go me