The mechanic is right... maybe.
You didn't specify what weber or "how much mild upgrade" cam you have. If
it's around 265-275 overlap, you first problem, all else being equal, is that
you and everybody else he's talking to likely have too much carb. A stockish
B motor does very well on stock needles on the HS4s with a "torque grind" cam
and the 270's range are fine on #6 or #7 needles. 90% or more B weber
installs are too much carb for not enough cam, and the low end goes away in a
sea of unburnt gas.
The other major issue is cam timing. Almost every cam I've seen comes
ground a few degrees off time. If not installed properly (finding spec with a
degree wheel etc) you will almost always end up with a cam that ends up
top-endy at the expense of bottom end. The only possible reason I know why
this happens is that the typical DIY cam buyer wants a wiz-bang increase in
revvy power and will complain if all that shows up is more torque and a
bigger power band...even though that's really what you are buying at this
level of upgrade.
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post------------------___________________
From: Enrique Claure <spanlab@ceibo.entelnet.bo>
Subject: Camshaft bull s...
Hi list, I took my MG to get the weber tuned. About four race cars were
waiting their turn for the dyno. I was very impressed at all the fancy
equipment they have. The mechanic in charge told me that I had to find out
the correct valve clearances for the cam (which I did) and also told me
that these mild cam upgrades tend to reduce the engines low end power at
1st and 2nd gear and are designed for speed on the track rather than fast
acceleration. I find this hard to believe since acceleration at the race
track is always important. Is he bull shitting me? Enrique
SPAN Inc HeadQuarter
PO BOX 6524
La Paz Bolivia
South America
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