[Roadsters] Head Porting

[Daryl Smith]

Thought some of you might be interested in an article in the July issue of
Classic Motorsports in which they build up an1800cc MGB engine.

The most interesting point (to me) that they make is this:
"....before the upgrades, our high compression ratio required premium unleaded
fuel that still left us with pinging problems. After the upgrades, we could
run unleaded regular on all but the hottest summer days without a single ping.
We attribute this gain to the porting, especially of the restrictive exhaust
ports. We've seen this time and again with B series engines - a well ported
head gets the heat out of the combustion chamber faster and keeps preignition
and detonation at bay."

Our engines are, aside from 8 ports rather than 5, quite similar in design,
with restrictive exhaust ports. There are 3 reasons to clean up those exhaust
ports - more power, less detonation, and a cooler running engine.

Now to be fair, part of the reason, I think, for having less detonation is
that the longer duration cam will also reduce the effective compression ratio.

And something that really bothers me, after spending nearly $2,000 on a cam,
lifters, cam gears, porting gaskets etc. they gained only 14 hp at the wheels!
Up from 64 to 78........

My hopes of getting 100 hp at the wheels of my 1800cc stroker are looking
pretty damn slim.......  :-(

Daryl