Re: Cat Converters - Restrictions?

[rusmaster <rusmaster@xxxxxxxxxxxxx>]

Hi Scott,
    Removeing the cat can give some top end hp, I've heard from 4-10hp
depending on other mods.  What it hurts is the torque.  Low end torque
needs a certain amount of  backpressure to give maximum torque where the
cam comes on.  To say, in the M30 stock engine, the peak torque is
204@4k RPM.  Removing backpressure may decrease this somewhat.  I've
never heard numbers on the decrease in torque by doing this.  So, if you
wan't top end, then the less restiction the better, but some is needed
for maximum torque.  This relates to intake systems also.  Thats why
some cars like the Taurus SHO use dual intake runners for each
cylinder.  This to to maximize the resonance of the intake to low and
high RPMs for the most torque and hp.  I believe it's long runners for
low end, short runners for high end.

Take Care,
Russ

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