In a message dated 10/4/99 6:06:10 PM, Herb_Goede@amsinc.com writes:
<< David ,
Surprisingly, straight through is not usually the best flow - especially
with small engines. Without some restriction/back pressure you lose
torque. (I don't know exactly why but someone on the list can explain it.)
And, you know what they say, horsepower sells cars but torque wins races.
The trick is to balance horesepower and torque to the best effectiveness of
both for your situation. That's why dynos were invented.
Herb
>>
I can really relate with this subject. My exhaust system starting at the
Engine is an LCB header, the pipe diameter exiting the LCB is 1.625" ID. Then
the 1.75" ID pipe which extends to just passed the rear axle and into a
Bullet style Turbo Muffler with a 2.0" ID pipe. As you may have noticed from
the header on back the system just keeps growing in diameter and the result
was a rather loud exhaust note (I kind of liked it but then there was my wife
and the neighbors) and NO low end torque. To take off from a stop I had to
raise the RPM's to about 2200 just to get it to move without stalling. In an
effort to reduce the noise level I decided to put a Suppertrapp exhaust tip
on the end of all this and was very pleased that it solved both the noise
level and made the engine idle smoothly for the first time. I am currently
running 10 discs and the noise level is around 1/2 to 2/3 of what it was, and
I can now take off from a stop at RPM's just above idle. The only draw back I
have found is the size of the 4" Suppertrapp (10" long with small glasspak
before discs) tip is a little large for a car that sits as low as a stock
Midget. Before putting on the new rear springs (stock rate) it would hit on
entering and exiting most driveways, Now it is rare but still hits on larger
dips.
OK just my .03¢ (too long to just be 2cents)
York Powell
'72 Midget - The Baby Car
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