Cutting spring pockets on SBC 462 heads

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Cutting spring pockets on SBC 462 heads

Post by VMC » Wed Nov 11, 2009 9:16 pm

When cutting these old "double hump" heads for 1.550 springs, can the cut go down to the same depth as the OE spring pocket w/o hitting water?

bill jones
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Post by bill jones » Wed Nov 11, 2009 9:31 pm

-seems to me that you had better expect to break into water----maybe not all of them but at least one or two anyway.

-Your chances of NOT hitting water is increased if you radius the cutters corner edge----but then the valve spring shims also need that same radius.

-I have occasionally had the problem--and ended up cutting the seat way out to accept spring cups--then epoxying in spring cups.

-I'm not exactly sure about the 1.550"s----I think they break thru just going out to about 1.460" springs so I may have used the cups for the 1.460" springs.

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Post by Shopboss » Wed Nov 11, 2009 9:44 pm

It's a gamble. Most of the older ones have enough meat but the newer ones, like the 186 get real thin. Play it safe, put a .060 shim in the spring seat and cut down to it. I've hit water on all of them at one time or another. With the selection of different length of valves, push rods, spring heights, high and low retainers and keepers that are so easy to get,There really isn't a need to take a chance. In the old days we would take a chance because it was easier to cut the pocket down than it was to find the right parts. Have you though about using a Beehive spring so you don't have to cut the head out as much?

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Post by ProPower engines » Wed Nov 11, 2009 10:19 pm

I have done lots with a 1.500 spring and only cut down to a .030 shim.
As mentioned before with a +100 long valve and a .050 hardened spring seat and -.050 locks you end up the same or use a taller spring depending on the installed height needed
Either way the 2 end springs need support on the outer edge.
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Post by trmnatr » Wed Nov 11, 2009 11:26 pm

We have a set of 291's with 1.46's and off the top of my head a .030 sim before we cut out

Also an identical pair of 461's with the half moon welded in to make them angle plug heads :roll: Not any more but hey back then it was the head

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Post by VMC » Wed Nov 11, 2009 11:47 pm

Thanks guys, .060" shim it is.

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Post by maxracesoftware » Thu Nov 12, 2009 1:51 am

VMC wrote:Thanks guys, .060" shim it is.
i would definetly use the .060" Shim to be safe !

all the #462 castings i've ported for SuperStock
i mill spring seats 1.635 OD->

1st= i use a modified 1.560" od cutter with a .060" corner radius
custom ground into that blade

2nd= then i put a .060" thick Shim on the seat
and come back with a 1.635" OD Cutter with
a custom ground .060 corner radius

those 2 cutter radius blend in to each other
and you put .060 shim and figure Installed Heights
using at least that .060 or .030 thick shim plus whatever more
Shims you might need.

on the #041x on just a few pairs
i've went all the way down with a 1.635 - 1.640 OD cutter
w/.060 corner radius

i've only seen 1 #041x head break thru @ 1.640 all the way down
but there are at least 2 versions or 2 different castings
that have different water jacket configurations around the
spring seats, ...but usually i always use the
1.560 w/.060 radius + 1.640 w/.060 radius on all those type castings
#462, #461, #041x

there are at least 3 or more versions of the #462's
again with some water jacket configurations around the spring seats
that are different

i had 1 SuperStock Racer from Baton Rouge
pickup up his #041x Heads here at my Shop,
1 of the #041x's had that different water jacket configuration
around the spring seats...and the other #041x didn't
..i had all the Installed Heights perfectly the same as could be

he left, drove back to Baton Rouge,
starts bolting the Heads on,
then calls me complaining i setup the Spring Heights
different from one Head to the other

he won't listen to reason over the Phone
so he drives back to my Shop that night
and i show him and let him personally check the Installed Heights
here with height mikes....well he leaves apologizing :)

one of the Heads looks like the Springs are way deeper than the other
its real obvious when you see them side by side,
but they are the same heights

all i'm saying be careful, as there are different casting versions
of the same #462's out there
and a 1.560" od cutter w/.060 shim as a depth stop is the wiser choice

on some of the #186's even 1.480 Cutter can get you into trouble
...always step cut a #186 or the old #492's ( were the worst )
heads w/ .060 shim at 1.480
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Post by trmnatr » Thu Nov 12, 2009 4:17 am

So Larry what would you do on 461's?

Go .030" shim and go out to 1.55" with the radius then put a .030" shim there and go out to 1.64" with a radius?

461, not 461x

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