More power!

Let me try to explain my view (and low buck engine power improvement idea) once again:

1) stock valve springs are beginning allow valve float by 5500 rpm and power production is lost at higher rpms
2) stock cam is not done by 5500 rpm -- it can make useable power to about 6500 rpm with better valve springs
3) shift points with better springs have to change so more "power under the curve" would be realized and the car will accelerate faster

stock spring rpm range between shifts = 4300 to 5800 rpm

with better valve springs that range = 5000 to 6500 rpm.

This is what the software says, it may be flawed (or overstating the effect), but that is why I posted the question if anyone had dyno or track numbers to back up what the software presented. A few people have supported the results with just the valve springs being changed, so it must be at least trending the right way. Making a big cam change requires tuning the OBD system, which is a whole 'nother can of worms (and $500+ and zillions of hours to do well yourself!) that might be avoided if the *real* difference between the 200/210 stock cam with better valve springs and a 224 cam with springs is only 30 peak hp.

Here is a statement to rattle the "stock cam is done by 5700-6000 rpm crowd" foundations: rpms of a given engine are limited by the valvetrain stability, cylinder head flow, and friction losses, not by the cam.

Thanks for the input!

Fred

RedHardSupra

iTrader: (1)

i concur. if you look at curves of ls1 vs ls6 (yea, i know, different head/cam/springs) but ls1 starts dying very soon after 5k. ls6 keeps on climbing till the redline.
my car is a living proof of how topend power combined with proper gearing can be a deadly combination without going into lumpy idles and emission unfriendly durations.
do yourself a favor, punch in stock values for z06 dyno, and do little numerical integration of 'area under the curve' for different shiftpoints, and you'll see how drastically numbers change. then do the same for ls1 dyno and while shifting higher helps, its nowhere near as beneficial as on a valvetrain setup that doesn't die early.

Andy02Z

iTrader: (1)

I found an article in Engine Masters that woulds be helpful here. They took a stock crate LS1 and made 420hp at 5600 rpm on an engine dyno. They noticed valve float at 5850 and switched to LS6 springs. After the swap they made 451 hp at 6000 rpm and pulled to 6600 while maintaining 449 hp. I will attach a pic of their results.

More power!

Just wanted to bump this back up so a few others could see that Andy02Z posted a nice table of values and I added a hp/torque graph towards the end of the replies.

Any SI guys with some dyno data?

Thanks!