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Re: Priorities!

To: garyb@pentek.com
Subject: Re: Priorities!
From: todd@nutria.nrlssc.navy.mil (Todd Mullins)
Date: Thu, 19 Jun 1997 11:31:42 -0500 (CDT)
Gary Burrell writes:

> First Off I highly recomend the pamplet "Performance MGB"
> by Moss UK.

Hadn't heard of this one.  What's the best way for a North American to
obtain this?

> A note on performance the first 10 % increase is easy to get
> the cost/ease of obtaining gets increasinly difficult/expensive.
> Also as you get more perfomance don't forget to address 
> braking, handling etc.

One distinction which I feel needs to be made here, and for some of you
it may fall into the realm of nitpicking, but I'll make it anyway:
Brake performance has nothing to do with engine performance.  Sure, it's
nice, and even recommended from a safety aspect, to upgrade your brakes'
performance.  But an increase in horsepower does not automatically
require a brake upgrade.  Braking is all about bringing a certain mass
from a certain speed to rest.  How you get to that speed is irrelevant.
The moment you transfer your foot from the right pedal to the middle
pedal, your beautiful ported-and-polished-and-cammed-to-the-hilt
performance motor simply becomes a 400 (give or take 50) pound lump of
metal.  For a 'B, the brakes are responsible for stopping ~2100 pounds
of mass, whether the motor puts out 60 hp or 160 hp.

The only case in which an engine upgrade necessitates a brake upgrade is
top speed.  If you increase your top speed, then braking FROM THAT TOP
SPEED will require more energy dissipation.  But it takes a whole lot of
horsepower to overcome the aerodynamics involved.

Please note that this is explicitly NOT a suggestion to take a cavalier
attitude regarding brake performance.  You can never have too much
brakes, no matter how powerful your engine is or how fast you go.  My
point is simply that there is no direct causal relationship between
motor and brakes.

> 3) Competition Style exhaust with Long Center branch Header
> I bought mine in stainless for about $400 for the complete
> set up.  Came with lifetime warranty.  (I needed a new
> exhaust so I went with this)
> (This gets air/exhaust out easier)

Actually, the dual-carb factory exhaust manifold is pretty darned good.
Does anybody have any hard numbers on the performance gain that a LCB
header nets?

> 5) Electronic Ignition kit.  I used the crane/allison kit
> but the new in the distribuiter type looks nice too.
> (cost $100) I also used a sport coil ($40)
> (More power to sparkplugs)

All the electronic ignition really gives you is reliability and
stability.  It doesn't actually make any more power.  The Sport Coil may
allow you to open up your spark plug gap, which will make power, but not
a whole lot (again - anybody have any hard data, so I can quit making
such qualitative musings?).

> After you've done this you probably want to change the carb
> needles on your SU's to something slightly richer

I've never quite understood this thinking.  If you need a richer
mixture, why not simply turn the jet screw a few flats?

-- 

Todd Mullins
Todd.Mullins@nrlssc.navy.mil    On the lovely Mississippi (USA) Coast

'74 MGB Tourer happy with new rotors and semi-met pads

That's me at the corner.
That's me at the stoplight,
Losing my transmission...

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