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Reply to "Looking for my VS build's sister"

@Stan Galat and @DannyP (and anybody else who cares to follow along our engine nerdiness)-

The camshaft/rocker combination (and duration/valve lift they provide) is only 1 piece of the puzzle of what makes power in an engine; heads, carbs, exhaust and compression also play a part (I know you both know this, but please bear with me).  As my 2 fellow Poopiehead friends have mentioned, better heads have the potential for way more power- but not in a stock cammed 1600.  Stock dual port heads rise in flow to about .400" valve lift, at which point the graph goes flat and lifting the valve further does nothing, hence why a lot of milder 1.1:1 ratio cams lift to just over that figure. 

Case in point- the Engle W110 that Ed mentioned has .430" valve lift (with 1.1's).  It's not only the duration increase (and subsequent rise in rpm's) but also the amount of time the valve stays open up near the .400" mark that allows the cylinder to fill with more air/fuel mixture, especially at the higher rpm's, that makes the increase in power.  Higher ratio rockers allow the cylinders to fill better and also add 4? 5? 6??? degrees more duration @ 0.050" so not only is there more upper rpm power but peak power (or redline) extends a little as well.  Now we're in (really) mild aftermarket cam territory.

In this instance the higher ratio rockers allow the stock heads to operate a little closer to their potential, with the carbs and exhaust being able to contribute more as well (neither have reached their limit in this combo either).  Would I bother trying the 1.4's on a totally stock 1600?  Like putting better heads on the dual carbed, stock cammed engine, there'd be no point without other modifications.

Properly ported stock valve heads will flow proportionately more to about .500" valve lift, but you can't use that here as they'd be a waste in a stock cammed 1600.  Even with the kadrons and 1 3/8" header, without more valve timing and valve lift there's no benefit.

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