1972 truck exhaust up-grade

Grumpy

The Grumpy Grease Monkey mechanical engineer.
Staff member
I'm taking the 72 to the muffler shop tomorrow to have the exhaust replaced from the manifolds back. I converted it to duals years ago but nothing lasts forever. It's a 1972 cheyenne super c-10 with a 350 and a RV cam. Now it has 2" pipes all the way back behind the wheels. Would 2 1/2" pipes be better or stick with 2" like it is now? I want it to sound healthy but not extremely loud. I'm 65 years old and have a hard enough time hearing on the freeway as it is.




a properly designed DUAL 2.5" exhaust (especially with a (X) pipe) should provide a noticeable improvement, as usual theres plenty of math to point you in the correct direction

in the ideal exhaust system youll want to have less than .5
(thats 1/2 a PSI of back pressure) at the engines peak rpm

Id also point out that cam timing matched to the exhaust scavenging has a huge effect on potential intake flow rates
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exarea.gif

http://www.exhaustvideos.com/faq/how-to-calculate-muffler-size-pipe-diameter/

http://www.mk5cortinaestate.co.uk/calculator5.php

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3" o.d = 2.87" diam. inside--approximately 6.5 sq inches of area
2.75 o.d = 2.62"diam. inside--approximately 5.4 sq inches of area
2.5 o.d = 2.37" diam. inside--approximately 4.4 sq inches of area
2.25 o.d = 2.12" diam. inside--approximately 3.5 sq inches of area

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well worth reading

http://www.popularhotrodding.com/engine ... ndex1.html


http://garage.grumpysperformance.com/index.php?threads/exhaust-components.361/

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http://garage.grumpysperformance.com/index.php?threads/calculating-required-exhaust-pipe-size.11552/

http://garage.grumpysperformance.co...-exhaust-pipe-diam-for-your-application.1730/

http://garage.grumpysperformance.com/index.php?threads/is-backpressure-hurting-your-combo.495/

http://garage.grumpysperformance.com/index.php?threads/building-an-exhaust-system-for-your-car.1166/

http://garage.grumpysperformance.co...-calculators-and-basic-math.10705/#post-72061

http://www.wallaceracing.com/Calculators.htm
 
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