Greetings listers! Hope you all had a joyous holiday season. I used part
of mine to get the spit back together.
This past summer, I blew a head gasket. My job has been somewhat hectic of
late, so progress on the spit was a little slower than I wanted. Actually,
it was supposed to be done in time to attend Triumphest in Laughlin this
year, but needless to say we didn't make that goal.
Having an extream case of "ship-wrights disease", I ended up installing a
new cam, pistons, bearings, etc. The cam is Ted Shumacher's TSI275-4 (.425"
lift, 275 degrees duration, 3000-6500 pwer range, flat power curve), the
pistons are 0.040 oversize, 9-1 compression. I also rebuilt the carbs
including new jets.
Anyway, the engines back together, relatively oil tight. I've got about an
hour on the new engine mainly setting the carbs. Took her out on the road
for about a mile (fully warmed up) and there seems to be less power now than
with my stock cam & pistons. Seems boggy.
I think it's probably a couple of things:
- First, the timing is probably off. The crank pully isn't indexed
properly, just a small hole marking what I think is TDC. I used a file to
mark 5-degree increments before and after which is better, but not by much.
So Question 1 is: "is this correct or does the hole mark some other timing
setting?" Q2 is: "Assuming that I can properly degree the pully, what
should the dynamic timing be for this engine?"
- Once the timing is set, I feel confident that I can get the carbs tuned
(pair of stock SU HS-2). However, not sure if there's anything I should do
different than normal considering the new cam other than avoid setting them
too lean. Any thoughts?
Sorry for so long.
Chris
'64 Spitfire4 BFC26375L
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