This is the cam in the engine:
Core# 08-000-8 CHEVROLET 262-400 V8 W/ Roller Cam (1987-98)
Intake lobe# (3410) 294 238 154 .350 .088 .075 .525 .560 .595
Exhaust lobe# (3357) 304 248 159 .333 .106 .092 .500 .533 .566
Lobe Separation Angle 104°
Intake Centerline 101°
Intake Duration @ .050 238°
Exhaust Duration@ .050 248°
LSA: 104°
Intake Centerline: 101°
IVO is 18.0 ° BTDC
IVC is 40.0 ° ABDC
EVO is 51.0 ° BBDC
EVC is 17.0 ° ATDC
steve cowan wrote: ↑Tue Mar 12, 2019 7:14 am
when you sized the heads on this build did you set you CSA by what you know or did you get them on a bench?? with the pinch set @ 1.9'' you will peak around 6500rpm,and is the avg CSA around 2.1''.
Disclaimer: I am not a cylinder head guy. The changes made to the heads were things that were suggested by someone that is ,I'm sure you can guess who that was, and a couple things I kind of winged...kind of the slept at a Holiday Inn thing. So there is no doubt they could be better. They never saw a flow bench. 2.1 avg is probably pretty close.
steve cowan wrote: ↑Tue Mar 12, 2019 7:14 am
looking at the intake manifold picture you posted i assume you done some work on the plenum and port match etc,how was fitment and port alignment??
I spent a complete afternoon on the manifold(but I'm slow). And that mostly involved squaring up the plenum, it was way off, and shaping the runner dividers, they needed a bit of weld from missing pieces of casting. Also just blending plenum into runners etc. No changes in csa to the runners. By the time it was all done the port match ended up very good. But it had to go on and off the engine a couple times to get there.
For myself personally, I can't see ever buying one of these manifolds.....crude and rough but can be made to work I guess.
steve cowan wrote: ↑Tue Mar 12, 2019 7:14 am
last question C H A D if you dont mind,i looked at the comp lobes 13064-13068
255- 271 @ 0.050'' 640'' lift
steve cowan wrote: ↑Tue Mar 12, 2019 7:14 am
how do you think this cam would perform with the compression and cylinder heads as is,
Intake Duration: 255
Exhaust Duration: 271
LSA: 108
Intake Centerline: 104
IVO is 23.5 ° BTDC
IVC is 51.5 ° ABDC
EVO is 67.5 ° BBDC
EVC is 23.5 ° ATDC
Only one way to find out. If they were for trying a cam on the dyno, I wanted to do something drastic for the sake of learning. These valve sizes, with these seat angles(and widths) are very window area limited, which definitely has some advantages, like plugging up overlap period some, better DC etc. But seem to run better than they (should).
I would like to see how well the little valve steep seat (protected) the bottom of the torque curve with a cam like this, as well as if it could bump peak hp up a decent amount and how that horsepower would be saturated at and around the horsepower peak with giving the small window area some (time). It may run like shit with it, who knows, I personally think it could be surprising, but if not I could always find something to use it in .