Some of the EM combos run very big intake lobes and advance the heck out of them to maximize (use up) the airflow potential of the heads by the 6500 rpm Cap set by the rules...Bishoff's 433" CHI headed Ford had a 106 split in at like 100 as I remember and Kasse built a motor that had (IIRC) a 98 degree ICL...and these guys have access to anything they want.

It's an over generization to say that advancing a cam to work well means you have the wrong cam....in an overported motor it can be great way to fill the holes well and still keep the Intake closing 'streetable'. an 8 degree larger intake lobe in 4 degrees earlier will have the same closing event, so if sized right for the port and as long as the roll on torque is sufficient down low it will probably make more top end power...won't it?

Ultradyne has ground tons of 108 spread cams that went in at 102 for years and years


It's dangerous and misleading to do more than generalize, all cams are application specific and more than 1/2 of the things I've learned that worked well or better for YEARS (particularly with strokers) seemed counter-intuitive to many 'experts'....but in recent years much of what has been flushed out of these jaw dropping engine-masters contests has made me feel a lot more open about talking about them.

Lobe spread and durations with a typical pushrod single cam motor are always at best a trade off....you have to give somewthing somewhere to get more somewhere else....and as correctly pointed out with a race app in a way it's easier because the clutch/cionverter and gearing can side step over the low efficency parts of the curve....in that respect a ture street motor is a lot more difficult to get as right as possible. Ask yourselves why have all the major auto companies spent umpteen millions develop their own forms of Variable cam timing (VTEC effects lift AND durations) and variable lobe spread tuning technology over the years? To improve VE across the powerband and make more power and/or torque with less cubes.