Aftermarket pipe I.D.

RiV wrote:

I doubt its a Hooker pipe, they always seemed to manage to get an exhaust shield that had a heart punched through it and were normally...

I doubt its a Hooker pipe, they always seemed to manage to get
an exhaust shield that had a heart punched through it and were
normally two piece stamped pipes. Bassani maybe, they did coned
pipes but were usually pretty quiet with welded on long silencers.
Home made.....I don't doubt that, its not very flowing.

Are you just curious about the manufacturer? Or trying to find out
if it will work well for a stk/modified engine? You could measure the
pipe best you can down the center to where the last cone is but
measuring to the end of where the angles of the pipe would
intersect. If you add that to the length of the exhaust port from the
piston face (deducting any overlap in the manifold) you will have
the pipes tuned length for a basic reference. If you can measure
the exhaust port duration then you could run the basic formula
if you know the engines designed or your intended RPM.

For example lets use 175 deg & 9500 rpm, many exhaust tuners use
1650fps as exhaust speed so why not:


175 x 1650=288750

288750÷ 9500=30.395" (rounded)

more duration=longer pie@same rpm (more time)
more RPMs=shorter pipe@same duration(less time)

Hope this helps, not trying to add confusion in any way-promise