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by Litle brother » Mon Apr 18, 2016 8:15 am
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Last edited by Litle brother on Thu May 23, 2019 1:54 pm, edited 2 times in total.
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Re: Mod-S cam VS 3.8 RSR cam in a 3.2 short stroke
by scarceller » Thu Apr 28, 2016 1:12 pm
The first ModS cam closes the intake valve at 52deg ABDC
While the second closes the intake at 65deg ABDC
If you do not up compression when using the more aggressive 2nd cam you won't like the results. The 2nd cam at 65deg ABDC will not have enough dynamic compression to achieve peak torque.
I also suspect it will not work well on a static compression of 10.3:1 but the first cam with 52deg ABDC should do OK at 10.3:1
The 65deg ABDC cam needs more compression to achieve a decent level of dynamic compression.
When you select a cam it's very important to select the correct static compression for that given cam.
While the second closes the intake at 65deg ABDC
If you do not up compression when using the more aggressive 2nd cam you won't like the results. The 2nd cam at 65deg ABDC will not have enough dynamic compression to achieve peak torque.
I also suspect it will not work well on a static compression of 10.3:1 but the first cam with 52deg ABDC should do OK at 10.3:1
The 65deg ABDC cam needs more compression to achieve a decent level of dynamic compression.
When you select a cam it's very important to select the correct static compression for that given cam.
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by Litle brother » Thu Apr 28, 2016 9:51 pm
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Last edited by Litle brother on Thu May 23, 2019 1:53 pm, edited 4 times in total.
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Re: Mod-S cam VS 3.8 RSR cam in a 3.2 short stroke
by scarceller » Fri Apr 29, 2016 5:31 am
At 10.3:1 that first cam is the better choice. Please do post back results.
Best of luck.
Best of luck.
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by Litle brother » Wed Nov 08, 2017 12:57 am
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Last edited by Litle brother on Thu May 23, 2019 1:52 pm, edited 1 time in total.
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Re: Mod-S cam VS 3.8 RSR cam in a 3.2 short stroke
by Steve » Wed Nov 08, 2017 7:54 am
Porsche driveline losses are 12%.
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by Litle brother » Wed Nov 08, 2017 4:25 pm
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Last edited by Litle brother on Thu May 23, 2019 1:53 pm, edited 1 time in total.
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Re: Mod-S cam VS 3.8 RSR cam in a 3.2 short stroke
by Steve » Thu Nov 09, 2017 3:04 pm
The 12% is what I measured after running several engines on our engine dyno, followed by running the same engine in the car on a Dynojet chassis dyno. Those are THE best ones to use for power measurement since the operator cannot do anything to skew or affect the results.
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