Some time back I posted a query to the list about cam problems I was
having with my Rover V8.
The end of the saga was this:
I suspected that the machine shop had taken too much off the heads
when they skimmed them - this turned out to be so....
Not only that, when they recut the valve seats, they were a bit
over enthusiastic on cylinders 7 and 6 [opposite sides] and cut the
seats very deep on the exhaust valves.
When we put the beast back togehter and checked the valve lift
individually [sheesh 16 valves!!!] we found:
Number 6 28 thou excess lift on the exhaust valve, number 7 the same.
all other valves 4-6 thou. excessive lift.
result was the valves weren't closing properly, some lifters were
bottoming put and bending rods, and the thing ran like a dog.
we fitted a set of adjustable rods and set the pre-load so that the
lifters wouldn't bottom out and bend the rods. Engine now runs
sweetly.... sort of!
Carbie is a Weber 38DGAs with 160 mains, CO level is running at
about 2% on 3000rpm. The engine just doesn't give you a nice shove
in the back when you boot it. Manifold is a standard Rover with the
tower machined off. Thoughts are that the machinist didn't do a good
job and somehow has altered the flow characteristics of the manifold.
Any comments, or advice on jetting etc.???
Peter B
Cape Town
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