Some Saturday Motor Fun
#51
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Hey now....
It is kinda funny though when your think of a tunnel ram 565 with 236/244 much smaller than 252/252 yet pulls peak hp at 6k. Port velocity??? Valve timing??? Wonder what peak hp woulda been with some 315 cnc heads. Btw I did end up with cams that even make yours look small. Lol
It is kinda funny though when your think of a tunnel ram 565 with 236/244 much smaller than 252/252 yet pulls peak hp at 6k. Port velocity??? Valve timing??? Wonder what peak hp woulda been with some 315 cnc heads. Btw I did end up with cams that even make yours look small. Lol
Like i said earlier, rpm capability, can be affected by valve lift, valve diameter, head flow, and so on. If his velocity was crapola, i dont think hed be making more torque at lower rpms than bcks smaller headed, smaller cammed, 10:1 548 with 305 afr heads.
Change the camshaft lobe, and valve size, and your velocity can go way up, or way down. It all plays a part. Thats what "custom" cams were meant to do. Design a cam for the engine package the customer has.
#52
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Getrdunn, just entering some information in pipemax.
With tahoe's specs, his cam, and 2.25 valve , it shows the intake system, is good for 5760rpm
By simply adding a 2.3 valve, with .700 lift, it raises to 6019 rpm. A 2.35 valve, with .730 lift, goes up to 6159 rpm.
Thats adding 400 additional RPM to the intake system, without a single change to the .050 duration.
By adding 1.85 rocker arm, which would increase his lift to roughly .685, his intake system went from 5760, to 5928 rpm.
While its just a computer program, seems pretty dam close to me, suggesting the engine would run out of steam with that combination of lift, duration, and valve size at 5700, and his dyno sheet seems to agree. Pretty neat stuff.
With tahoe's specs, his cam, and 2.25 valve , it shows the intake system, is good for 5760rpm
By simply adding a 2.3 valve, with .700 lift, it raises to 6019 rpm. A 2.35 valve, with .730 lift, goes up to 6159 rpm.
Thats adding 400 additional RPM to the intake system, without a single change to the .050 duration.
By adding 1.85 rocker arm, which would increase his lift to roughly .685, his intake system went from 5760, to 5928 rpm.
While its just a computer program, seems pretty dam close to me, suggesting the engine would run out of steam with that combination of lift, duration, and valve size at 5700, and his dyno sheet seems to agree. Pretty neat stuff.
#53
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Getrdunn, just entering some information in pipemax.
With tahoe's specs, his cam, and 2.25 valve , it shows the intake system, is good for 5760rpm
By simply adding a 2.3 valve, with .700 lift, it raises to 6019 rpm. A 2.35 valve, with .730 lift, goes up to 6159 rpm.
Thats adding 400 additional RPM to the intake system, without a single change to the .050 duration.
By adding 1.85 rocker arm, which would increase his lift to roughly .685, his intake system went from 5760, to 5928 rpm.
While its just a computer program, seems pretty dam close to me, suggesting the engine would run out of steam with that combination of lift, duration, and valve size at 5700, and his dyno sheet seems to agree. Pretty neat stuff.
With tahoe's specs, his cam, and 2.25 valve , it shows the intake system, is good for 5760rpm
By simply adding a 2.3 valve, with .700 lift, it raises to 6019 rpm. A 2.35 valve, with .730 lift, goes up to 6159 rpm.
Thats adding 400 additional RPM to the intake system, without a single change to the .050 duration.
By adding 1.85 rocker arm, which would increase his lift to roughly .685, his intake system went from 5760, to 5928 rpm.
While its just a computer program, seems pretty dam close to me, suggesting the engine would run out of steam with that combination of lift, duration, and valve size at 5700, and his dyno sheet seems to agree. Pretty neat stuff.
#54
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It is just interesting how cam duration always gets discussed where people want to make their peak power at a said rpm yet heads, valve size and induction can change it in a hurry with the same cam. Combo, combo....
#55
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Looks like you could've pulled a few jets out for sure. For cam duration vs cylinder head comparisons, here's a very similar combo with a lunati 238/248 114. Same cubes, same heads, a little less comp. 1 7/8 ID headers with 3" exhaust and mufflers. No accessories. Vic Jr. Hp950
[ATTACH=CONFIG]564863[/ATTACH]
[ATTACH=CONFIG]564863[/ATTACH]
#57
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Looks great. That should work very well for you, and I bet upgrading to a quick fuel 1050 4150 carb or something similar down the road will pick up a fair bit more power too. Nice build.
#59
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So AFR heads and custom cam same power as 088 GM heads and off the shelf cam.
Marine Kinetics really killin it!
Marine Kinetics really killin it!
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#60
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