> i was wondering if anyone out there with the 360 engine ever
> converted to screw in studs to adapt small block chevy roller rockers
> and where they found guide plates. i'm in the middle of doing this
> and so far all i've heard was to use small chevy guide plates, cut
> them, and weld them back together???
Important! Do not use Chev 1.5 rockers as they are shorter than the AMC
1.6's, and the tip will not correctly contact the valve. This will
result in a broken rocker stud, the lifter thrown out of it's bore, no
oil pressure, and a blown engine. In addition this will drop the valve
lift to .398 (with a stock cam) and will result in a loss of power.
There are proper 1.6 rockers that fit the AMC commonly available and
relatively inexpensive from Crane, Speed Pro, Comp, etc. The earlier
AMC (up to about 73, recommended casting number 993) heads came
equipped with screw in studs (a shouldered stud) so no conversion is
necessary, but the later heads can be easily converted to screw in
studs, similar to doing so on a Chev. For guide plates I use 5/16 big
block Chev plates cut apart, with a little grinding they fit fine. I
don't bother welding them back together and haven't had any movement in
1800 passes. The earlier heads have a cast in alignment slot so guide
plates are not necessary unless the slots are worn. Wear can be a
problem, especially with a higher load valve spring. I haven't checked
the ratio of the later bridged pivot rockers, but I've checked numerous
earlier style rockers and found them to be usually 1.61 or 1.62, so
assuming the quality is similar (dangerous) just putting on roller
rockers would have little to no effect on performance. The early
rockers even seem to be plenty strong, I've used them on springs
approaching 400 lbs over the nose and never broke one. However, if you
get into a that load valve spring I would recommend good rockers to
reduce valve guide wear.
Ken
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