The additional length will not effect the engine performance in any noticeable way.
You may want to check air filter clearance with the additional height.
I know. PMO tall manifolds make more torque. Well I have never seen it on a dyno sheet.
Don't get me wrong, I like Richard and his products. This claim is just tuff to swallow.
It is common knowledge that you must change the intake runner about 5 inches in order the notice a difference.
I have no way to prove it but I would bet that the Varioram system offers 10 inches of change.
The long runner technology came from a study on intake pulses pioneered by Dave Long first in college and then in the Chrysler engine technologies department in the 50s.
For you old timers, Chrysler made a slant 6 engine that had a 4 foot long intake. The engine slanted towards the right fender then had the carbs mount right next to the left fender.
Some of you might even remember the old Dodge cross ram manifold.
How long were those runners? 2.5 ft ?
