Mancini rocker questions...

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Icetech

Icetech

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K.. so pushrods showed up today and i got home all excited to finally get this together... Mancini sends no info at all with their rockers, not a big deal it seems pretty common sense.. big spacer between the rockers, small shim spacers on the outside of the pairs of rockers.

So i'm pre fitting the rockers to make sure no issues and as soon as i tighten down the old downs the rockers get so tight i can barely move them (This is only tightening using a nut driver for fitting purposes).. Loosen slightly and all is fine, it's not the hold down blocks twisting side to side.. tried moving them around and same issue. 1 or 2 cyls move fine when tight but most are rubbing bad..
Looking for specs the only person i found that mentions side to side play on rockers is moparjoe who likes .016 i have .000..

So.. not sure what to do, i'm 99% sure i got the shims/spaces and hold downs in the right places.. Considered "Clearancing" the hold down blocks but wouldn't get them square enough and that would end badly...

P.S. measured the shims .047-.049 each.. the spacers between the rockers were all matching but i don't recall the exact number at the moment.

Thanks for any help.. praying i don't need to order thinner shims and wait 2 more weeks :(
1694038383979.jpeg
 
P.S.. I believe my rocker hold down bolts should be 25lb-ft but.. locktite or antiseize?
 
mopar head said:
Probably exactly what you`ll have to do.
Click to expand...
Icetech said:
K.. so pushrods showed up today and i got home all excited to finally get this together... Mancini sends no info at all with their rockers, not a big deal it seems pretty common sense.. big spacer between the rockers, small shim spacers on the outside of the pairs of rockers.

So i'm pre fitting the rockers to make sure no issues and as soon as i tighten down the old downs the rockers get so tight i can barely move them (This is only tightening using a nut driver for fitting purposes).. Loosen slightly and all is fine, it's not the hold down blocks twisting side to side.. tried moving them around and same issue. 1 or 2 cyls move fine when tight but most are rubbing bad..
Looking for specs the only person i found that mentions side to side play on rockers is moparjoe who likes .016 i have .000..

So.. not sure what to do, i'm 99% sure i got the shims/spaces and hold downs in the right places.. Considered "Clearancing" the hold down blocks but wouldn't get them square enough and that would end badly...

P.S. measured the shims .047-.049 each.. the spacers between the rockers were all matching but i don't recall the exact number at the moment.

Thanks for any help.. praying i don't need to order thinner shims and wait 2 more weeks :(
View attachment 1716138335
Click to expand...


I bought a Sears belt sander almost specifically for this job years ago. I’ve showed pictures before how I mark every rocker and every hold down for position. I would remove material from the sides of the hold downs and shim as needed to center up each and every rocker. Only after I was satisfied would I bolt everything down and then measure for pushrod length. Step by step. Caution of course is needed using these sanders.

7DAE13B7-6B8C-4BDF-BB39-2B81226A784A.jpeg
 
Sometimes the centering bushing needs a little shaving to get proper alignment/ clearance
 
pittsburghracer said:
I bought a Sears belt sander almost specifically for this job years ago. I’ve showed pictures before how I mark every rocker and every hold down for position. I would remove material from the sides of the hold downs and shim as needed to center up each and every rocker. Only after I was satisfied would I bolt everything down and then measure for pushrod length. Step by step. Caution of course is needed using these sanders.

View attachment 1716138345
Click to expand...
Beats the hell out of a file.:thumbsup:
 
pittsburghracer said:
I bought a Sears belt sander almost specifically for this job years ago. I’ve showed pictures before how I mark every rocker and every hold down for position. I would remove material from the sides of the hold downs and shim as needed to center up each and every rocker. Only after I was satisfied would I bolt everything down and then measure for pushrod length. Step by step. Caution of course is needed using these sanders.

View attachment 1716138345
Click to expand...
I almost thought of doing that on the hold downs.. wouldn't take much but i don't trust myself.. gonna find a shim kit to order..

It's all a learning process.. just getting mad that winter is almost here and i don't even have this motor in.. and wanted to have a new motor for next year.. my plans were too big for how lazy i am :)
 
On the upside it looks like i got the pushrods correct.. bout 1.5-2 threads on the adjuster.. will just need to figure how many thought 1 turn is so i can lash (hydraulic)
 
Icetech said:
I almost thought of doing that on the hold downs.. wouldn't take much but i don't trust myself.. gonna find a shim kit to order..

It's all a learning process.. just getting mad that winter is almost here and i don't even have this motor in.. and wanted to have a new motor for next year.. my plans were too big for how lazy i am :)
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Speedmaster offers them as does summit
 
Icetech said:
On the upside it looks like i got the pushrods correct.. bout 1.5-2 threads on the adjuster.. will just need to figure how many thought 1 turn is so i can lash (hydraulic)
Click to expand...
Likely 20 threads per inch, so one full turn would be .050.
Could also be 24 tpi,so .042 per one full turn.
To tune up my rocker stands, I used some 80 grit, and 240 grit sandpaper (or emery cloth) glued to a pane of glass (flat!). Roll in circles, remove metal slowly on the 80, cleanup with 240.
Time consuming and tiresome? You bet. Necessary if you want them right, and almost free. (Used the same setup to true up holley metering blocks and bodies.)
 
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33IMP said:
Likely 20 threads per inch, so one full turn would be .050.
Could also be 24 tpi,so .042 per one full turn.
Click to expand...
yeah, i think it's 24 it's pretty fine, going to just measure a turn to be 100%.. i mean it doesn't have to be THAT accurate but rather be sure..

BTW.. was just looking up something and ran into this.. just goddamn...
 
You could just take the blocks to a machine shop and have em skim cut to whatever clearance you want since right now you’re at zero.
 
TT5.9mag said:
You could just take the blocks to a machine shop and have em skim cut to whatever clearance you want since right now you’re at zero.
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naw, the issue is i don't knwo what i'm at cause it's actually negative, the rockers are actually binding so have no idea what i would need to take off. The car isn't going anywhere in a hurry i can wait for shims.
I ordered new axles also and have a 4.57 pig to put in, trans to build.. plenty to get done still. Hoping i can modify my tapered axle backing plates to work with normal flanged axles.. will see soon :)
 
Icetech said:
Thanks PBR, i ordered the 20's and 40's.. their prices are good but the shipping is pretty bad :( Summit only had .015 and .020s i think 20s and 40s will give me more to work with.

Thanks for all the help :)
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I know you need them now but just a heads up. I order stuff like this during the Black Friday 40% off sale. I get free shipping on my orders and no tax so it’s a triple win win win. Some stuff is so cheap you buy it just to have it.
 
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