Picked a cam for lq9 408 w/tfs 215s
10-24-2018, 12:15 PM
#24
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Originally Posted by irocbrninrubber
All, thanks for the info. SO can a cam that has longer duration be tamed down a little by having wider LSA?
Usually if street manners are a concern, you end up reducing duration to preserve your efficiency and torque.
If you REALLY want to keep the duration and run a wider LSA, then you will likely want more compression to restore throttle response. That helps compensate for late IVC and early EVO
MAVN post below likely runs pretty good compression to work with that cam, as an example. Displacement and compression are great cam tamers.
10-24-2018, 12:29 PM
#25
Short answer yes, but it depends what you want to compromise. You want later IVC so low end is anemic? Or you want to push exhaust valve even earlier so you lose torque?
Usually if street manners are a concern, you end up reducing duration to preserve your efficiency and torque.
If you REALLY want to keep the duration and run a wider LSA, then you will likely want more compression to restore throttle response. That helps compensate for late IVC and early EVO
MAVN post below likely runs pretty good compression to work with that cam, as an example. Displacement and compression are great cam tamers.
Usually if street manners are a concern, you end up reducing duration to preserve your efficiency and torque.
If you REALLY want to keep the duration and run a wider LSA, then you will likely want more compression to restore throttle response. That helps compensate for late IVC and early EVO
MAVN post below likely runs pretty good compression to work with that cam, as an example. Displacement and compression are great cam tamers.
10-24-2018, 12:54 PM
#26
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10-24-2018, 04:08 PM
#27
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I am not sure who you spoke with on this, but I would like to talk to you about this one in more detail if you have not purchased a camshaft yet. If you would, send all the details of your build to Steven at CamMotion.com. I want to make sure you get the right camshaft for the job.
10-25-2018, 08:39 AM
#29
I've had the pleasure of talking to Bob regarding the Titan King LS7 LLSR cam and I'm really leaning in that direction when it comes time to go back into the LSX motor. Steven we've already talked about this new build. It's a Gen 3 block with a 4.030 bore, 3.622 stroke with 12cc domes and 823's up top and once I've made up my mind on the intake manifold I'll be calling you back.
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40 years of Championship Winning Experience • Superior 8620 Steel Camshaft Cores • Quiet, Smooth & Powerful Lobe Design • Virtually Unlimited Lift and Duration Combinations • Finish Polished For Quiet Operation • Cam Doctor Printout With All Cams
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www.CamMotion.com • ☎ 225-926-6110 • Like Us On Facebook!
The Switch Is On To Cam Motion!
40 years of Championship Winning Experience • Superior 8620 Steel Camshaft Cores • Quiet, Smooth & Powerful Lobe Design • Virtually Unlimited Lift and Duration Combinations • Finish Polished For Quiet Operation • Cam Doctor Printout With All Cams
The Industry's Best Customer Service
www.CamMotion.com • ☎ 225-926-6110 • Like Us On Facebook!
10-28-2018, 07:55 PM
#30
TECH Enthusiast
I stopped giving any eff words over LSA. its a calculated result is all it is. Like displacement. I care more what bore and stroke are than the displacement.
Two engines at 383. One is 3.9 bore x 4.0 stroke. Other is 4.1 bore and 3.622 stroke. Same displacement but will behave quite differently.
LSA is a result of calculating the valve events and is helpful for calculating valve events from the cam spec, which I really just view as short hand notation.
Want to know what rpm it makes peak torque and HP? Look at IVC and intake runners length. Want to know how smooth it will idle? Look at IVO and EVC to calculate overlap. Want to know how well it carries past peak? Look at EVO and overlap. And none of that matters without also looking at displacement and compression.
224/224-112+0
232/240-112+4
Both make peak torque and power at same rpm because 44 IVC. 232 will sound cooler at idle because more overlap (12 vs zero) will carry better past peak because overlap and EVO of 56 vs 44. 224 will drive easier because less overlap. 232 will make more power because more duration. So what did LSA do? Nothing.
What if we took that 232/240 cam and made it 232/232-114+6? We changed LSA and exhaust duration right? No. Wrong. We moved the EVC event 8 degrees. Other three events are still identical. LSA is just a calculation result.
Ok
/rant.
Lol
Two engines at 383. One is 3.9 bore x 4.0 stroke. Other is 4.1 bore and 3.622 stroke. Same displacement but will behave quite differently.
LSA is a result of calculating the valve events and is helpful for calculating valve events from the cam spec, which I really just view as short hand notation.
Want to know what rpm it makes peak torque and HP? Look at IVC and intake runners length. Want to know how smooth it will idle? Look at IVO and EVC to calculate overlap. Want to know how well it carries past peak? Look at EVO and overlap. And none of that matters without also looking at displacement and compression.
224/224-112+0
232/240-112+4
Both make peak torque and power at same rpm because 44 IVC. 232 will sound cooler at idle because more overlap (12 vs zero) will carry better past peak because overlap and EVO of 56 vs 44. 224 will drive easier because less overlap. 232 will make more power because more duration. So what did LSA do? Nothing.
What if we took that 232/240 cam and made it 232/232-114+6? We changed LSA and exhaust duration right? No. Wrong. We moved the EVC event 8 degrees. Other three events are still identical. LSA is just a calculation result.
Ok
/rant.
Lol