Scavenging is a thing, even if some don't believe in it. A dual 2-1/4" system can support upwards of 400hp.
I believe in scavenging, but it ties into engine rpm and the duration of that rpm to gain the benefit. There is no scavenging during stop and go traffic
True, but it does happen once you are underway. Stacking slow moving exhaust pulses decreases both power and fuel efficiency. A correctly sized, and and improperly sized system will have a similar performance in stop-and-go traffic. Only one will produce maximum performance otherwise.
was presant in the SoCal header movement, they will all tell you that the headers were designed with being easy to bend the tubing and fitting the engine compartment. Once that was done--- the advertising department took over for the sales. Years ago I needed headers for a 360 in my Cuda, Thorley sold them , but wanted to look at the before spending $1000. 2-bolt flanges and crush areas, 1 tube was made in 8 sections and the tubes were unequal lengths. Was it ever tested??? No, all it did was replace the stock manifold.
I remember when GM hit the TBI era in the trucks, and everyone wanted 3-inch duals with Flowmasters on their 350. I remember a whole lot of upset people complaining about torque loss. I made a bunch of money taking those system off.
Until then it was over carb and over cam - for bragging rights and simply big is better ignorance - then the big diameter exhaust joined the club. And remains there to this day. If only we all drove around at 8,000rpm all day. (of course there's always someone who will say they do)
Could you please post a pic or two and school us as to putting dual SU carbs on a Ford banger. I’ve been thinking about this for awhile now but have not seen any reference to it before now…
The Jalopy Journal
