This isn’t stock, anyone identify this

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AZ-Nick

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I removed the valve covers from my new to me 340 and I can see that it’s not stock. Can someone identify what I have here and what I need to know about it.
Thanks

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Looks like stock or Crane adjustable iron rockers with Mancini or eBay hold downs. The hold down blocks are too thick to be speedmaster small block units. Are the shafts completely surrounded by the block and the rocker stand milled flat?
 
Those are aftermarket rockers as well as the block style hold downs. Crane made rockers like that (with the locknut) as well as a few other companies.
 
Those are aftermarket rockers as well as the block style hold downs. Crane made rockers like that (with the locknut) as well as a few other companies.
Correct! I forgot that Erson and Isky also made that style of rocker. I’m sure there were others as well…
 
To add my 2 cents.
Looks like step headers and 340 X heads and power steering.
 
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Those are Mopar Performance hold downs made my Crane
I agree. I bought mine from Mancini back in the day. Crane 1.6 incase ya,wonder what was next to the hold downs, on Mopar Comando heads.

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Having the adjustable rockers is nice. Does it bother any one else with the iron rocker riding that tight to the hold downs even if they are billet?
 
Having the adjustable rockers is nice. Does it bother any one else with the iron rocker riding that tight to the hold downs even if they are billet?
If you look really close, you can see clearance. Besides, that's what the oil filter's for. lol
 
Like the hold down was ever a weak link.

The problem with the OE hold downs is the lack of bearing area for the rocker. Stock cams and springs it’s not usually an issue but quicker lobes and higher spring loads and the OE hold downs will chew up the rocker.
 
The problem with the OE hold downs is the lack of bearing area for the rocker. Stock cams and springs it’s not usually an issue but quicker lobes and higher spring loads and the OE hold downs will chew up the rocker.
Well them there rockers don't look too far from the OEM application. The aftermarket rocker shaft hold down surely can not hurt. Thanks for for the info concerning higher spring loads.
 
When I assembled my heads, I found a set of 5/16" grade 8 bolts. I've accidentally broken a few of the over the years.
 
Correct! I forgot that Erson and Isky also made that style of rocker. I’m sure there were others as well…
I forgot Erson. I often wondered if one company made them all and the companies just put their name on the box. Just curious. The aftermarket ones all had the lock nut. The interference fit adjusters on the stock ones work well. A new adjuster usually takes care of any loose issues.
 
I forgot Erson. I often wondered if one company made them all and the companies just put their name on the box. Just curious. The aftermarket ones all had the lock nut. The interference fit adjusters on the stock ones work well. A new adjuster usually takes care of any loose issues.

Probably. There are not that many companies out there who can extrude a rocker or forge one. So they probably have 2 or 3 options to get the stuff made.

And maybe not even that many today.

Of course, even thought the same manufacturer may make rockers for several companies, I would think that each company would have its own design and geometry and such. Or maybe they just copy others stuff and sell it.
 
LOL a red X for something I know has never been a problem. I'll take that with a grain of salt. :thumbsup:
 
LOL a red X for something I know has never been a problem. I'll take that with a grain of salt. :thumbsup:
Lol
Yeah the instructions that came with my Hughes hold down kit says .005 to .010
Side clearance.
I set mine at .010 works great and much quieter too.
I think some would consider that to tight because the factory stuff was so loose.
Now I will say that's with adjustable rocker arms.
Maybe the stock paddle style rockers need more room, but I'm not sure why it would?
 
I say, "if it is not broke, don't fix it". I like the stock set up best. Never had a issue with my 340's. There is a reason a torque spec is called on bolts. Newer cars even more so.
 
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