Tapered Rocker Shims

So I've been trying to sort out my rocker train on my 383/451 build over the past few weeks and I'm at a bit of an impasse. I'm attempting to use Crane 1.6 Iron rockers and my wipe pattern wants an .040 shim.

In an attempt to avoid potential pedestal split problem, I trimmed the shims back. This helps but doesn't completely solve the pinch problem at the top of the saddle. Someone had posted awhile back that someone sold tapered shims but I can't find them. Hughes sells straight aluminum shims and Mancini sells straight steel ones.

I've already wasted a lot of time and money trying to sort out this setup, I'm not sure what to do next, short of tearing heads apart and having having valve stem tips shortened.

In hindsight, it would have been way easier to just buy Harland Sharps for this build which would move the wipe pattern outwards, but its way overkill for such a mild street motor.

Does anyone know if a tapered rocker shim is actually available?

b3racingengines.com

Use nothing else.

I agree with madscientist, seek out B3racing. Mike did the correction for the geometry on my Trick Flows and they are perfect.

Thanks I'll give him a call Monday!

I bought a new set of longer exhaust valves to correct my issue.Seeme the whole stem is hardened so I didn't need lash caps and the swipe is perfect!

Thanks but longer valves would move the pattern the opposite way (move towards intake) of what these rockers need (move towards exhaust).

I wound up using .080 lash caps on my 500 build with Harland Sharps and Eddy heads to shift pattern towards intake, similar to what you did with longer valves.

Centering the sweep sometimes increases the sweep width - not what you want.

Good to know, thanks for the info. So B3 says perpendicular to valve at 1/2 lift the target if I read correctly?

I can see where flat pads with rocker shaft blocks would be advantageous. Just a PITA for such a relatively mild build.

If the rocker design is mid-lift: yes.
If not (and they won't tell you specifically) that just moves the error (not 90) to the pushrod side and may result in a smaller "window" of lift X duration. Some compromise (where neither is at 90) may be better, but generally the valve side is more critical.

Poly what does that mean "mid lift" (newbie here) & I'm dealing with the same issue.

I've always used what the old Mopar drag race engineers said in their drag race seminars years ago, shoot for the roller tip to start out on the inner third of the valve stem, closest to the shaft, and have the roller tip roll across the center of the stem at mid lift to the outer third at max lift Most of the heads I've set up that way end up with about .045 to .060 width on the total sweep
IHTH

So would .045 to .060 scrub apply for non-roller tips?

I don't remember about non roller tipped rockers and how much sweep. I would think the minimum is best, but there is much more math and science to it that I'm not willing to say definitively if that's correct.

Did you talk to Mike at B3? He's very knowledgeable and willing to help. I say he's your best option.

I did message Mike with my specifics, waiting to hear back on his take.

Quick Update, Mike did not have a solution for Iron Rockers and suggested I switch to PRW rollers with his relo kit. Unfortunately, 1.6 PRWs are out of stock for a month or so. I found that if I raised the Iron Cranes .080, the pattern got real narrow and moved to the exhaust side. So raising them .080 and moving shaft centers towards intakes about .080-.100 would be about perfect. Meanwhile I'm done messing with these things and I'm not willing to wait any longer. So.....I'm selling off ALL of my Crane Iron stuff to raise cash for Harland Sharps which is what I should have done in the first place

This is good advice in my book.

Just an update, I appreciate the inputs but in the interest of availability and $ I went with "Edelbrock" versions of Harland Sharps 700016KE, no shims, no adapters, my ARP shaft studs still work, my custom Manton pushrods for the crane irons still work showing 1.5 threads, pattern starts just inside center of valve, centered at 1/2 lift, finishes just outside center of valve with about .060-.070 pattern width. Thanks Cab and hats off to Shanon's for hooking me up.