Thanks Tom, that's very interesting.
I was reading some Hemi history recently and they talked about long runner
vs short runner. When people drove the two cars, not knowing which was which,
they all felt the long runner car was much more powerful. The engineers thought
it was because the short runner motor built power more gradually and didn't
suddenly shove you back in the seat.
Bryan
Thomas E. Bryant wrote:
> Bryan,
>
> This last weekend, Joe Mondello spoke at the NW Banquet revealing gobs
> of info on this subject. At one time it was thought that bigger was
> better, but that myth has been abandoned long ago. Joe talks about a wet
> flow bench that gives lots of info on the air induction, including what
> happens in the combustion chamber.
>
> The appearance of the restrictor plate in Nascar has given a great deal
> of info in this area. The heads I have were purchased from the Sabco
> Team. They were restrictor plate heads. The intake runner was reduced in
> size by about 1/3 with epoxy. I understand that two things helped to
> overcome some of the HP losses in the restrictor plate engines were
> higher compression and higher intake velocity. Some of the same thinking
> is also used in getting the exhaust out.
>
> If you remember the Ram Induction that Chysler was using in the early
> 60s, you will note that their design was changed from the original long
> rams to shorter ones for high performance engines. The long runners gave
> gobs of torque in the lower rpms, but sacrificed hp on the top. The
> shorter runners moved the torque up the rpm scale. The idea behind this
> system was to use the momentum of the air movement to stack air against
> the intake valve while closed. This gave a more dense charge when the
> valve opened.
>
> A Muffler Shop friend, Dave Hooper, and I did some experimenting with
> the exhaust system on my roadster in the early 60s. We used four 2"
> pipes, two on each side tying the cylinders in pairs to each pipe and
> extending them back above the rear wheels. It added a great deal to the
> low end torque. However, as in the case with the Chysler setup, it
> suffered on the top end. Just some food for thought!
>
> Tom, Redding CA - #216 D/CC
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