Interesting observation ... I hadn't thought about that. I'm sure you are right, but I doubt you could tell without a stopwatch or dyno.

Consider equal-length headers (extractors) vs. un-equal length headers. Yes, the equal-length give slightly more horsepower (because the pulses are more evenly spaced?)

I suspect it's a somewhat more important in the intake runners. However, in many stock cast intake manifolds some runners are longer than others. Think of straight-six manifolds with single carbs.

For a competition race car any improvements are important to gain an edge on the other competitors ... but for a street car does it really matter?

for all you LHD dattos out there has any one ever put IDA's on a 1200 you could get a manifold cut it in half and elbows in it they might hit the bonnet though just a thought

That picture looks familiar...
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