Idaho
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This is basically a continuation of this thread about choosing a carb and intake, but moving on to the camshaft.
http://www.forabodiesonly.com/mopar/showthread.php?t=178560
My basic recipe started here:
http://www.hotrod.com/techarticles/e...e/viewall.html
This is their setup:
LA timing case and accessories. LA oil pan.
M1 intake w Speed Demon 750
Mopar performance electronic ign.
Edelbrock RPM heads (9:1).
Stock lifters/retainers.
Comp 1.6:1 roller rockers.
Comp Magnum push rods.
Hooker 1 3/4 headers.
Comp custom grind:
Comp's XFI hydraulic roller lobes No. 3016 and No. 3037 on the intake and exhaust, respectively, 230/236 at 0.050 on a 110-degree lobe separation, 0.576/0.571-inch lift
Read more: http://www.hotrod.com/techarticles/...block_mopar_engine/viewall.html#ixzz1oIX3ZzbR
With input from members here, I'll likely make a few substitutions:
RHS X heads
Performer RPM intake
Holley 670 vac secondaries
Summit headers
stock rockers and push rods
I'm in the process of educating myself about cams. I'd like to start by clearing up a point of confusion to me found in this article.
My thinking was that lower LSA should reduce low rpm power by lowering dynamic compression because the overlap is increased. The gain should be at the higher rpm where overlap allows high velocity airflow to pack in more air after TDC.
So I ask (like O'Reilly) where am I going wrong here?
http://www.forabodiesonly.com/mopar/showthread.php?t=178560
My basic recipe started here:
http://www.hotrod.com/techarticles/e...e/viewall.html
This is their setup:
LA timing case and accessories. LA oil pan.
M1 intake w Speed Demon 750
Mopar performance electronic ign.
Edelbrock RPM heads (9:1).
Stock lifters/retainers.
Comp 1.6:1 roller rockers.
Comp Magnum push rods.
Hooker 1 3/4 headers.
Comp custom grind:
Comp's XFI hydraulic roller lobes No. 3016 and No. 3037 on the intake and exhaust, respectively, 230/236 at 0.050 on a 110-degree lobe separation, 0.576/0.571-inch lift
Read more: http://www.hotrod.com/techarticles/...block_mopar_engine/viewall.html#ixzz1oIX3ZzbR
With input from members here, I'll likely make a few substitutions:
RHS X heads
Performer RPM intake
Holley 670 vac secondaries
Summit headers
stock rockers and push rods
I'm in the process of educating myself about cams. I'd like to start by clearing up a point of confusion to me found in this article.
LOBE SEPARATION ANGLE
By choosing a cam with the correct LSA for the engine's intended usage, you can have your cake and eat it too. First of all, the LSA is ground into the cam at the factory and cannot be changed. It represents the number of degrees, in crankshaft rotation, that separate the intake lobe centerline from the exhaust lobe centerline. A wider LSA figure, i.e. 112-116 degrees, moves the lobe centerlines further apart and will smooth your idle due to the decrease in overlap that creates. The lower the figure, i.e. 106-110 degree, moves the centerlines closer and will increase bottom end power, but your idle will suffer along with it. We did a test a few years back running five different LSAs on otherwise identical cams in the same engine. What we found was that the cams with a 108-110 LSA worked best all around. But idle vacuum was higher with the wider LSA cams (112-114) and this would translate to better idle quality. Bottom line here is that most cam companies have put lots of effort into selecting the proper LSA for the cam's intended usage so you'd be wise not to second-guess them.
Read more: http://www.superchevy.com/technical...c_right_cam_choice/viewall.html#ixzz1oIRRmO00
My thinking was that lower LSA should reduce low rpm power by lowering dynamic compression because the overlap is increased. The gain should be at the higher rpm where overlap allows high velocity airflow to pack in more air after TDC.
So I ask (like O'Reilly) where am I going wrong here?