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stock eliminator roller cam lobe

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stock eliminator roller cam lobe

Posted: Sun Feb 10, 2019 11:33 pm
by Rowdy Yates
Can a lobe be done, that has more lift (vs normal SE* racing cams) & has more area under the curve vs a normal cam....or does some make 1 already? Just would like to know. Was looking at a old engine power show with Samtech and there Copo limited cam. Figure if it has that much more area under the curve why not have one with the lift wanted.

Re: stock eliminator roller cam lobe

Posted: Mon Feb 11, 2019 12:54 pm
by Sumtingwong
So a high lift Dwell nose profile? How much additional area are you looking for and where? And what does your current camshaft map out at?

Re: stock eliminator roller cam lobe

Posted: Mon Feb 11, 2019 1:35 pm
by Rowdy Yates
Just was asking brother guy's at bullet explained it, there harsher for what i was thinking....800 lift with a good amount of dwell time. Was told harder to control.

Re: stock eliminator roller cam lobe

Posted: Mon Feb 11, 2019 1:37 pm
by Rowdy Yates
https://www.powernationtv.com/episode/E ... po-a-go-go

Re: stock eliminator roller cam lobe

Posted: Mon Feb 11, 2019 2:20 pm
by Sumtingwong
Rowdy Yates wrote: ↑Mon Feb 11, 2019 1:35 pm Just was asking brother guy's at bullet explained it, there harsher for what i was thinking....800 lift with a good amount of dwell time. Was told harder to control.
You building a LS for a class car? What are the details?

Re: stock eliminator roller cam lobe

Posted: Mon Feb 11, 2019 5:08 pm
by Rowdy Yates
No class just HP wanted........Have 2 cams for 2 different heads just asking a question I didn't know.

Re: stock eliminator roller cam lobe

Posted: Thu Feb 21, 2019 10:39 am
by cgarb
Probably because there is only so much of the angle you can work with...so many degrees duration. If you want more lift it takes away from the amount of dwell you can have. You can't just pop the valve open, if the lobe was that steep it would side load the lifter and bind.

Re: stock eliminator roller cam lobe

Posted: Thu Feb 21, 2019 11:04 am
by pdq67
Might consider getting more lift from a rocker arm ratio increase??

pdq67

Re: stock eliminator roller cam lobe

Posted: Thu Feb 21, 2019 11:18 am
by CamKing
If you're not limited to a given lift, by rules, it's easier on the valvetrain, to get the area, by increasing the lift, then by adding dwell at max lift.

Re: stock eliminator roller cam lobe

Posted: Thu Feb 21, 2019 7:50 pm
by MELWAY
CamKing wrote: ↑Thu Feb 21, 2019 11:18 am If you're not limited to a given lift, by rules, it's easier on the valvetrain, to get the area, by increasing the lift, then by adding dwell at max lift.
Is this because there is more real estate to slow the motion down at nose before changing direction

If you look at 2 almost identical lobes. Same durations everywhere. But 1 has .400” love lift the other .440”.
Which one is more stable and easy on parts?

Re: stock eliminator roller cam lobe

Posted: Thu Feb 21, 2019 9:01 pm
by 1972ho
Like this same spec ones a stocker.

Re: stock eliminator roller cam lobe

Posted: Fri Feb 22, 2019 9:57 am
by Stan Weiss
MELWAY wrote: ↑Thu Feb 21, 2019 7:50 pm
CamKing wrote: ↑Thu Feb 21, 2019 11:18 am If you're not limited to a given lift, by rules, it's easier on the valvetrain, to get the area, by increasing the lift, then by adding dwell at max lift.
Is this because there is more real estate to slow the motion down at nose before changing direction

If you look at 2 almost identical lobes. Same durations everywhere. But 1 has .400” love lift the other .440”.
Which one is more stable and easy on parts?
I am not a cam designed. But the only way I can see them having the duration ever where is if the .400" lobe is the .440" with the top removed. If that is the case the .440" lobe will be more stable and easy on parts.

I look forward to seeing what Mike has to say.

Stan

Re: stock eliminator roller cam lobe

Posted: Fri Feb 22, 2019 3:14 pm
by paulzig
CamKing wrote: ↑Thu Feb 21, 2019 11:18 am If you're not limited to a given lift, by rules, it's easier on the valvetrain, to get the area, by increasing the lift, then by adding dwell at max lift.
If you have a cam that is .550 vs one that is .750" how much dwell over the nose would you need on the .550" cam to offset the .200" lift difference?

Re: stock eliminator roller cam lobe

Posted: Sat Feb 23, 2019 12:02 am
by Stan Weiss
paulzig wrote: ↑Fri Feb 22, 2019 3:14 pm
CamKing wrote: ↑Thu Feb 21, 2019 11:18 am If you're not limited to a given lift, by rules, it's easier on the valvetrain, to get the area, by increasing the lift, then by adding dwell at max lift.
If you have a cam that is .550 vs one that is .750" how much dwell over the nose would you need on the .550" cam to offset the .200" lift difference?
This is using a Cam DR file for a Comp Cams solid roller. The card give numbers with a 1.65:1 rocker. I used a 1.8:1 to get around 0.750" net valve lift. Notice the duration at the valve at 0.550" lift. I can no calculate how much area would be lost if the nose is changed to dwell.

Stan

Code: Select all

VALVE_____Lift______Opens___Closes__Duration
_________________Deg_BTDC__Deg_ABDC_____________Area
_________0.00000____47.64_|__84.31_|_311.95_|__66.54
_________0.00600____44.76_|__81.03_|_305.79_|__66.52
_________0.01000____43.06_|__79.05_|_302.11_|__66.51
_________0.02000____39.31_|__74.68_|_293.99_|__66.44
_________0.04000____33.26_|__67.84_|_281.10_|__66.25
_________0.05000____30.73_|__65.09_|_275.82_|__66.10
_________0.10000____20.51_|__54.22_|_254.73_|__65.33
_________0.15000____12.49_|__45.87_|_238.36_|__64.32
_________0.20000_____5.47_|__38.66_|_224.13_|__62.89
_________0.25000____-1.08_|__31.97_|_210.89_|__61.51
_________0.30000____-7.43_|__25.63_|_198.20_|__59.53
_________0.35000___-13.73_|__19.29_|_185.57_|__57.53
_________0.40000___-20.17_|__12.81_|_172.64_|__54.87
_________0.43000___-24.12_|___8.83_|_164.71_|__53.17
_________0.45000___-26.81_|___6.11_|_159.31_|__52.27
_________0.50000___-33.85_|__-0.96_|_145.20_|__48.41
_________0.55000___-41.55_|__-8.63_|_129.82_|__44.66  <<<<<<<<<<<<<<<<
_________0.60000___-50.21_|_-17.28_|_112.51_|__39.44
_________0.65000___-60.44_|_-27.48_|__92.07_|__33.12
_________0.70000___-73.69_|_-40.58_|__65.73_|__24.28
_________0.75000__-100.89_|_-66.71_|__12.40_|___4.51
CAM
_________0.00600____56.01_|__92.95_|_328.96_|__39.04
_________0.01000____50.50_|__87.43_|_317.93_|__39.00
_________0.02000____41.86_|__77.65_|_299.51_|__38.83
_________0.04000____30.98_|__65.35_|_276.33_|__38.48
_________0.05000____26.89_|__60.95_|_267.84_|__38.29
_________0.10000____11.47_|__44.82_|_236.29_|__37.07
_________0.15000____-0.70_|__32.36_|_211.67_|__35.53
_________0.20000___-12.08_|__20.95_|_188.87_|__33.37
_________0.25000___-23.72_|___9.23_|_165.51_|__30.83
_________0.30000___-36.39_|__-3.48_|_140.13_|__27.21
_________0.35000___-51.53_|_-18.59_|_109.88_|__22.27
_________0.40000___-72.76_|_-39.65_|__67.59_|__14.31
_________0.43000__-103.12_|_-68.78_|___8.10_|___1.72

Re: stock eliminator roller cam lobe

Posted: Sat Feb 23, 2019 11:29 am
by Stan Weiss
The original lobe with the top removed.

Code: Select all

VALVE_____Lift______Opens___Closes__Duration
_________________Deg_BTDC__Deg_ABDC_____________Area
_________0.00000____47.64_|__84.31_|_311.95_|__57.70
_________0.00600____44.76_|__81.03_|_305.79_|__57.68
_________0.01000____43.06_|__79.05_|_302.11_|__57.66
_________0.02000____39.31_|__74.68_|_293.99_|__57.59
_________0.04000____33.26_|__67.84_|_281.10_|__57.40
_________0.05000____30.73_|__65.09_|_275.82_|__57.25
_________0.10000____20.51_|__54.22_|_254.73_|__56.48
_________0.15000____12.49_|__45.87_|_238.36_|__55.48
_________0.20000_____5.47_|__38.66_|_224.13_|__54.05
_________0.25000____-1.08_|__31.97_|_210.89_|__52.66
_________0.30000____-7.43_|__25.63_|_198.20_|__50.68
_________0.31900____-9.82_|__23.24_|_193.42_|__49.74
_________0.35000___-13.73_|__19.29_|_185.57_|__48.68
_________0.40000___-20.17_|__12.81_|_172.64_|__46.02
_________0.45000___-26.81_|___6.11_|_159.31_|__43.43
_________0.50000___-33.85_|__-0.96_|_145.20_|__39.56
_________0.55000___-41.55_|__-9.55_|_128.90_|__35.82
CAM
_________0.00600____56.01_|__92.95_|_328.96_|__34.13
_________0.01000____50.50_|__87.43_|_317.93_|__34.08
_________0.02000____41.86_|__77.65_|_299.51_|__33.92
_________0.04000____30.98_|__65.35_|_276.33_|__33.57
_________0.05000____26.89_|__60.95_|_267.84_|__33.38
_________0.10000____11.47_|__44.82_|_236.29_|__32.15
_________0.15000____-0.70_|__32.36_|_211.67_|__30.61
_________0.20000___-12.08_|__20.95_|_188.87_|__28.45
_________0.25000___-23.72_|___9.23_|_165.51_|__25.92
_________0.30000___-36.39_|__-3.48_|_140.13_|__22.30
_________0.31900___-41.74_|_-10.22_|_128.04_|__20.73
With dwell added to get same area.

Code: Select all

VALVE_____Lift______Opens___Closes__Duration
_________________Deg_BTDC__Deg_ABDC_____________Area
_________0.00000____47.64_|_116.31_|_343.95_|__66.52
_________0.00600____44.76_|_113.03_|_337.79_|__66.50
_________0.01000____43.06_|_111.05_|_334.11_|__66.48
_________0.02000____39.31_|_106.68_|_325.99_|__66.41
_________0.04000____33.26_|__99.84_|_313.10_|__66.22
_________0.05000____30.73_|__97.09_|_307.82_|__66.07
_________0.10000____20.51_|__86.22_|_286.73_|__65.30
_________0.15000____12.49_|__77.87_|_270.36_|__64.30
_________0.20000_____5.47_|__70.66_|_256.13_|__62.87
_________0.25000____-1.08_|__63.97_|_242.89_|__61.48
_________0.30000____-7.43_|__57.63_|_230.20_|__59.50
_________0.31900____-9.82_|__55.24_|_225.42_|__58.56
_________0.35000___-13.73_|__51.29_|_217.57_|__57.50
_________0.40000___-20.17_|__44.81_|_204.64_|__54.84
_________0.45000___-26.81_|__38.11_|_191.31_|__52.25
_________0.50000___-33.85_|__31.04_|_177.20_|__48.38
_________0.55000___-41.55_|__22.45_|_160.90_|__44.64
CAM
_________0.00600____56.01_|_124.95_|_360.96_|__39.23
_________0.01000____50.50_|_119.43_|_349.93_|__39.19
_________0.02000____41.86_|_109.65_|_331.51_|__39.02
_________0.04000____30.98_|__97.35_|_308.33_|__38.67
_________0.05000____26.89_|__92.95_|_299.84_|__38.48
_________0.10000____11.47_|__76.82_|_268.29_|__37.26
_________0.15000____-0.70_|__64.36_|_243.67_|__35.72
_________0.20000___-12.08_|__52.95_|_220.87_|__33.56
_________0.25000___-23.72_|__41.23_|_197.51_|__31.02
_________0.30000___-36.39_|__28.52_|_172.13_|__27.40
_________0.31900___-41.74_|__21.78_|_160.04_|__25.84
Stan
ab-comp161-dwell.gif
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