1.5 or 1.6 roller rockers.

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1967formulaS

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Hi guys,
Advice on which ratio roller rockers to choose?
1.5 or 1.6.
My gut says 1.5 with this ridiculous cam profile. Solid flat tappet, matching lifters and valve springs. Iron closed chamber heads.

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I like the 1.6 here. Your valve lash is losing some lift at .014, plus the pushrod angle isn't dead on either, so that loses a little more. Not as bad as a small block, but there is some loss. Plus there's a little power to be had. Nothing complicated about it, either.
 
I like the 1.6 here. Your valve lash is losing some lift at .014, plus the pushrod angle isn't dead on either, so that loses a little more. Not as bad as a small block, but there is some loss. Plus there's a little power to be had. Nothing complicated about it, either.
Agree w/ this.-I`ve got a one step hotter solid roller w/ 1/6`s on it.
 
Talk to Mike at B3 Racing Engines LLC - Performance Engine Building and Mopar Valvetrains

He is a member on here as well. I gave him my set up information and he went out of his way to help me. I went with 1.6 rockers as he advised and every thing went great.



^^^^^^^^^THIS^^^^^^^^^^^^

The best thing you can do is let Mike help you out. You'll be happy you did.

As for the rockers I'd use 1.6 every day of the week and twice on Sunday. Your cam is close to what I run on a 340 and I used 1.6 rockers so I could NET a bit over .600 lift.

If you have the piston to valve clearance and retainer to guide clearance take the lift. Lift is your friend.
 
Ok, so got my 1.6 rockers.
Sat my heads on a just held em in with a couple of bolts finger tight.
Pulled the new rockers apart, checked the threads and chased a couple that were a bit ordinary.
Test fitted them to see where they sit and, 4 rockers on both sides are a fair bit out. I'm definitely going to need more shim packs, but a couple of the rockers closest to the hold Downs, need to move toward the holddown.

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Looks like PRW rocker arms. If that is the case then you'll need to make a visit to your local machine shop to get them to work.
 
Looks like PRW rocker arms. If that is the case then you'll need to make a visit to your local machine shop to get them to work.
Machine shop ? He can't do the fitting in his garage. Please explain.
 
Looks like PRW rocker arms. If that is the case then you'll need to make a visit to your local machine shop to get them to work.
Customer brought me a set that looked like those to use about 10 years ago. We went to visit, not the local machine shop, but the local dumpster.
 
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Lol.
I get what your saying. I simply don't have the budget for big dollar rockers. The prices are crazy here in Australia.
My options are, continue on and see if this will work or go back to hydraulic and be done with it.

I've moved a few things around, and have managed to centre them all. Surprisingly (sarcasm) the holddowns are not all exactly the same, so I was able to swap them around to achieve the rockers being central.

Question: Is it essential to have a shim between the rocker arm and the billet holddown? If not, I think I have this first obstacle beat.

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Agree,you need billet rockers with better clearance to valve tips.
And spring retainers.
 
You must have a washer between hold down and rocker. You can use a flat file on hold down to gain clearance.
 
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