Cam Specs - Hard numbers, really!
#31
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Revolver Cams:
Duration / Intake: 262º
Duration / Exhaust: 264º
Valve Lift / Intake: 11.4 mm
Valve Lift / Exhaust: 11.5 mm
Link:
http://www.revolvercams.com/mitsubishi.html
Duration / Intake: 262º
Duration / Exhaust: 264º
Valve Lift / Intake: 11.4 mm
Valve Lift / Exhaust: 11.5 mm
Link:
http://www.revolvercams.com/mitsubishi.html
#34
I'm not so sure about the whole idea of using a larger exhaust cam than intake cam.
I have some airflow data now in an excel spreadsheet, but I should have some better data tomorrow, assuming the track doesn't get rained out tonight.
Basically, I think I lost a lot of airflow and power when I swapped in my HKS 272 exhaust cam in place of the 264 I used to have in there. Now I am back to 264/264. I'll see if I got anything back. I may even try the 272I/264E setup.
I have some airflow data now in an excel spreadsheet, but I should have some better data tomorrow, assuming the track doesn't get rained out tonight.
Basically, I think I lost a lot of airflow and power when I swapped in my HKS 272 exhaust cam in place of the 264 I used to have in there. Now I am back to 264/264. I'll see if I got anything back. I may even try the 272I/264E setup.
#35
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Originally Posted by ShapeGSX
I'm not so sure about the whole idea of using a larger exhaust cam than intake cam.
I have some airflow data now in an excel spreadsheet, but I should have some better data tomorrow, assuming the track doesn't get rained out tonight.
Basically, I think I lost a lot of airflow and power when I swapped in my HKS 272 exhaust cam in place of the 264 I used to have in there. Now I am back to 264/264. I'll see if I got anything back. I may even try the 272I/264E setup.
I have some airflow data now in an excel spreadsheet, but I should have some better data tomorrow, assuming the track doesn't get rained out tonight.
Basically, I think I lost a lot of airflow and power when I swapped in my HKS 272 exhaust cam in place of the 264 I used to have in there. Now I am back to 264/264. I'll see if I got anything back. I may even try the 272I/264E setup.
#36
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I have built a twin turbo Viper, several single and twin turbo LS1s with Incon or Lingenfelter kits and worked on dozens of 2JZs, 4G63s, EJ20s etc and every single one of those cars runs better with more intake duration than exhaust and retarded exhaust timing to further decrease the area of lift during the overlap period....
#40
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Originally Posted by Fenris Ulf
I have built a twin turbo Viper, several single and twin turbo LS1s with Incon or Lingenfelter kits and worked on dozens of 2JZs, 4G63s, EJ20s etc and every single one of those cars runs better with more intake duration than exhaust and retarded exhaust timing to further decrease the area of lift during the overlap period....
The exhaust cam lobe immediately precedes the intake cam lobe, not the other way around. If the exhaust cam is retarded, it reduces the lobe separation angle and increases valve overlap.
Cam design is dependent upon many variables, some of which include the flow characteristics of the intake ports, the same for the exhaust ports, and how these two sets of numbers flow with respect to each other.
Because the exhaust gas is energized by its heat, the static port flow for the exhaust can be about 75% of that of the intake to give relatively equal real world numbers. Therefore, if a particular cam setup gives balanced flow, upsetting the balance by making one cam larger may not be to our benefit. Of course, we are speaking in generalities here.
In short, static cam specs do not tell us enough about what is really going on for us to make arbitrary determinations. All we can do by looking at cam specs is compare them on paper and judge how one set should behave in comparison to another.
Last edited by Ted B; Aug 19, 2004 at 12:11 PM.
#44
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Depends on what you want to measure. Give us an idea of what you want to know and I can better help you.
[EDIT] Forgive me, I wasnt thinking about what I was saying.
I think its quite obvious your looking for the specs relavent to this post.. In order to do so they must be installed and degreed accordingly.
[/EDIT]
[EDIT] Forgive me, I wasnt thinking about what I was saying.
I think its quite obvious your looking for the specs relavent to this post.. In order to do so they must be installed and degreed accordingly.
[/EDIT]
Last edited by JustDSM; Sep 17, 2004 at 06:43 AM.
#45
ok not sound like a newbie... as i have helped build plenty of engines... but why is lift important... i realize the wider a valve opens the more room, but wouldn't duration be more important on the HP side of things. Also... not that i would ever do this, but can you mix brands of cams to create more HP or a better power curve