David Ambrose wrote:
>
> Mark Rayborn wrote:
> >
> > As I was searching the archives for info, I came across a post regarding
> > a small cam sold by Northwest Imports. They call it a "street
> > performance cam". Has anyone tried it? Do you think it will make any
> > noticeable difference? Are HS4's on a regular intake hot enough for the
> > cam?
You will likely give up some torque to get the horsepower, but given the
MGB's long stoke motor, you will be best to retain the torque. Aside
from the brief stint at 4500 RPM, you aren't up there very much. That
said, you can probably go to a hotter camshaft and not lose very much.
It may be more fun to drive, but I've always felt the MGB engine likes
to be revved as much a a diesel tug boat motor.
> > the money on a crossflow aluminum head. Any little tweaks I can do
> > during the rebuild process to enhance performance?
> >
> Blueprinting the engine helps. I used Hepolyte (sp?) 4 ring pistons.
> The rest is stock, but assembled carefully. Most of the valve train
> parts were either rebuilt or replaced.
Yes, blueprinting will help, but it won't be very cheap. However, you
will have an engine that is better than what came from the factory and
it will last longer. Don't forget the basics to the engine rebuild.
Check and document all tolerances. If you have the time and resources,
check the ring gaps, piston to wall clearances, and ALL bearing
clearances. If your machine shop is competent and you trust them, have
them clean up your ports, and of course, a FULL balance of the engine,
including front pulley and flywheel will reap great benefits on your
motor. It's free horsepower, aside from the machine work.
I've found the MGB motor is not an a highly modifiable motor. To get
power, you have to spend quite a bit of money. You would be best to
stick to the basics and build a high quality motor. If you want power,
get the V-8. Nuff said! The 2 Liter pistons are nice, but they can't
shake a stick at the V-8. Anyway, I don't think Mark was even heading
this direction.
Make sure you have good components outside the motor. New ignition
pieces can help (points, condenser, rotor), or just chunk the points and
get the electronic ignition, especially if your car is daily driver.
The Crane ignition multi-spark boxes do wonders with the carbs. Also,
make sure your carbs are in good condition. Mic that camshaft if used,
to make sure you aren't losing your better breathing engine. Also,
someone on the list mentioned smoothing and opening the 1.5" SU carbs
for better breathing. If you're handy, you can get quite a bit more out
of the motor. Takes sweat labor, not money, too! And if you're really
die-hard, then there's ceramic coatings and dry film lubricants. You
keep the heat in the combustion chamber, which equals power. Dry film
lubes and coatings can increase part lives quite a bit, and reduce
sliding/rotating friction. Coatings cost around $100, if you apply
yourself and have access to sand blasting equipment.
Sorry for the random jumble of thoughts, but I wanted to cover a lot of
things. Email for more info. I can fill your ears with more stuff.
Hope this helps!
Jay
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