Re: camshaft lobe sep
[Re: mopar dave]
#2702190
09/30/19 09:50 AM
09/30/19 09:50 AM
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Joined: Jan 2003
Posts: 15,439 Val-haul-ass... eventually
BradH
Taking time off to work on my car
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Taking time off to work on my car
Joined: Jan 2003
Posts: 15,439
Val-haul-ass... eventually
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First, I responded to your PM already.
Second... unless you're going to run about 15:1 CR and spin it 8000 RPM, no way in He11 I can see you needing a cam w/ that wide of an LSA N/A (unless it also recommends reducing the duration quite a bit, which wouldn't make sense to me, either).
DV has written a lot of stuff, and I own a lot of his books. However, some of his approaches, such as how he determines cam LSA based upon overlap, etc., seem tailored to fit all his SBC testing, despite his claims that they're universally applicable (for the most part).
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Re: camshaft lobe sep
[Re: mopar dave]
#2702203
09/30/19 10:27 AM
09/30/19 10:27 AM
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Joined: Jan 2003
Posts: 14,539 So. Burlington, Vt.
fast68plymouth
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You can computer model and theorize all that cam stuff endlessly.
In the end, there’s only one way to know if it’s what your motor of combo wants....... and that’s to test it.
If the computer says it’s better, but your car is slower.........which are you going to believe?
Faster ramps will require higher spring loads(to achieve equal rpm), which will reduce the reliability/longevity of the components used....... no way around it.
The cam you have tries to balance that somewhat.
Would a more aggressive cam make more power? Probably.
The question becomes, how much more power does it make........and can I live with the ramifications of the more aggressive cam with the way the car is being used?
114lsa? That doesn’t turn out very well in most cases with a build like yours.
68 Satellite, 383 with stock 906’s, 3550lbs, 11.18@123 Dealer for Comp Cams/Indy Heads
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Re: camshaft lobe sep
[Re: mopar dave]
#2702212
09/30/19 10:43 AM
09/30/19 10:43 AM
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Joined: Jan 2003
Posts: 11,786 Portage,michigan
B3422W5
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Years ago i ran a 107 LSA comp cam Dwayne specced on a 416 motor that was just under 12 to 1 Scott Brown knew my motor specs well and suggested i try a 112 cam he designed Car went 10.38 with the 107 cam, best ever with the 112 was 10.55 The 112 killed the 60 foot. Acted like novacaine when the car launched. My take was more vert and compression it might have liked the 112 more. Real good heads and lots of compression imo are necessities for an NA street/ strip motor to make that swap worthwhile at the track, maybe huge cubic inches might help a good bit top. Probably would
69 Dart GTS A4 Silver All steel, flat factory hood, 3360race weight 418 BPE factory replacement headed stroker, 565 lift solid cam, footbrake street/strip car Best so far, 10.32 1/4 1.41 best 60 foot 6.56 at 104.17
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Re: camshaft lobe sep
[Re: fast68plymouth]
#2702213
09/30/19 10:44 AM
09/30/19 10:44 AM
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Joined: Jan 2003
Posts: 15,439 Val-haul-ass... eventually
BradH
Taking time off to work on my car
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Taking time off to work on my car
Joined: Jan 2003
Posts: 15,439
Val-haul-ass... eventually
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You can computer model and theorize all that cam stuff endlessly.
In the end, there’s only one way to know if it’s what your motor of combo wants....... and that’s to test it.
I'm the freakin' poster child for that... I don't even bother w/ the software stuff anymore. Empirical data all day long, please.
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Re: camshaft lobe sep
[Re: B3422W5]
#2702251
09/30/19 01:04 PM
09/30/19 01:04 PM
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Joined: Jan 2003
Posts: 13,496 Marion, South Carolina [><]
an8sec70cuda
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Years ago i ran a 107 LSA comp cam Dwayne specced on a 416 motor that was just under 12 to 1 Scott Brown knew my motor specs well and suggested i try a 112 cam he designed Car went 10.38 with the 107 cam, best ever with the 112 was 10.55 The 112 killed the 60 foot. Acted like novacaine when the car launched. My take was more vert and compression it might have liked the 112 more. Real good heads and lots of compression imo are necessities for an NA street/ strip motor to make that swap worthwhile at the track, maybe huge cubic inches might help a good bit top. Probably would I had a similar experience. Scott Brown spec'd a cam for a 10.8:1 compression Edelbrock headed 440 combo I had w/ a 112 LSA (254/266 at fifty). I wasn't happy w/ it at all. Switched to an Ultradyne on a 108 (259 at fifty straight pattern) and the car went quicker and faster.
CHIP '70 hemicuda, 575" Hemi, 727, Dana 60 '69 road runner, 440-6, 4 speed, Dana 60 '71 Demon 340, no drivetrain, on blocks behind the barn '73 Chrysler New Yorker, 440, 727, 8.75 '90 Chevy 454SS Silverado, 476" BBC, TH400, 14 bolt '06 GMC 2500HD LBZ Duramax
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Re: camshaft lobe sep
[Re: an8sec70cuda]
#2702255
09/30/19 01:10 PM
09/30/19 01:10 PM
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Joined: Jan 2003
Posts: 19,544 Las Vegas
Al_Alguire
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A lot of factors to consider when the LSA is being chosen for a particular cam. As for not seeing that kind of LSA on an NA engine depends on the NA engine. My junk is 117 NA, our dragster runs a 114 and the heads up car, which is also NA is even wider....Just depend on the application
"I am not ashamed to confess I am ignorant of what I do not know."
"It's never wrong to do the right thing"
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Re: camshaft lobe sep
[Re: mopar dave]
#2702258
09/30/19 01:24 PM
09/30/19 01:24 PM
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Joined: Aug 2003
Posts: 43,744 Bend,OR USA
Cab_Burge
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I Win
Joined: Aug 2003
Posts: 43,744
Bend,OR USA
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I was told years ago(40+) by several people who worked for three different camshaft makers in SO CA that the LSA would help determine where the motor would make the most power, closer LSA would loose some power in the upper RPM limits(above 4000 RPM back then) and wider would loose power down low, below 4000 RPM. I have used several different grinds in BB Mopars with 104 and one 101 LSA solid lifter cams The one motor with the 101 LSA was a pump gas street stock stroke iron headed 440 that was installed at 99 on the ILC, the owner said that motor pulled real hard up to and over 7500 RPM The 104 Isky grinds where used in several different higher (above 11.5 to 1)compression M.W. bracket motors, I would shift those motors them between 6400 and 7200 RPM
Last edited by Cab_Burge; 09/30/19 01:25 PM.
Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)
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Re: camshaft lobe sep
[Re: BradH]
#2702261
09/30/19 01:31 PM
09/30/19 01:31 PM
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Joined: Jan 2003
Posts: 31,203 Oregon
AndyF
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Oregon
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Yeah Pro Stock stuff has been in the 120 range and some Super Stock stuff I've seen down in the high 90's. So LSA and LCA are just what it takes to get the job done. How you figure out what it takes to do the job is the tricky part.
Last edited by AndyF; 09/30/19 01:36 PM.
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Re: camshaft lobe sep
[Re: AndyF]
#2702320
09/30/19 05:14 PM
09/30/19 05:14 PM
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Joined: Jan 2003
Posts: 11,786 Portage,michigan
B3422W5
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I Live Here
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Yeah Pro Stock stuff has been in the 120 range and some Super Stock stuff I've seen down in the high 90's. So LSA and LCA are just what it takes to get the job done. How you figure out what it takes to do the job is the tricky part. Yep. Like i said above a bigger motor with good heads and lots of compression is going to shine with a wider LSA camshaft. Hemi super stock because of rules is a much more limited motor and a more rpm band sensitive narrow LSA cam will shine. For the typical bracket 10 and 11 second car that isn't light like a pro stock or heads up car, a narrower cam is typically gonna make the car ET better Not gonna find to many 15 to 1 440’s or 416’s with eddie heads bracket racing because among other reasons fuel is expensive. Most “ class “ cars run narrower stuff. Talking stock and superstock Chip, yea, Scott Brown was all about wider cams, no matter the situation. I was stupid letting him talk me into trying his cam. It didnt make any sense, and the results ended up predictable
69 Dart GTS A4 Silver All steel, flat factory hood, 3360race weight 418 BPE factory replacement headed stroker, 565 lift solid cam, footbrake street/strip car Best so far, 10.32 1/4 1.41 best 60 foot 6.56 at 104.17
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Re: camshaft lobe sep
[Re: AndyF]
#2702333
09/30/19 06:04 PM
09/30/19 06:04 PM
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Joined: Aug 2011
Posts: 2,905 Pattison Texas
CSK
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master
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Pattison Texas
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I used to chase this stuff around but these days I use 112 in all of my street stuff with 4 degrees of advance. I don't even think about it anymore. Maybe I'm leaving peak power on the table but I don't care. 112 in at 108 works great on pump gas street engines, especially with EFI. 112 lsa is 112 lsa , no matter how much you advance the cam
1968 Charger COLD A/C Hilborn EFI 512ci 9.7 compression, Stealth heads, 4.10 gear A518 ODtrans 4100lb,10.93 full street car trim 2020 T/A 392 Stock 11.79 @ 114.5
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Re: camshaft lobe sep
[Re: AndyF]
#2702335
09/30/19 06:14 PM
09/30/19 06:14 PM
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Joined: Jan 2003
Posts: 11,786 Portage,michigan
B3422W5
I Live Here
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I Live Here
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Portage,michigan
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I used to chase this stuff around but these days I use 112 in all of my street stuff with 4 degrees of advance. I don't even think about it anymore. Maybe I'm leaving peak power on the table but I don't care. 112 in at 108 works great on pump gas street engines, especially with EFI. On the street where the big inch big blocks you primarily fool with will blow the tires off at the hit, you likely wouldnt notice any difference. You are not wringing cars out at the track, are you? Its not like the difference is huge in most cases anyhow. I learned over the years( at least to me) it takes 3 tenths or so to notice in the seat of the pants driving around after changes on the street and then going to the track. Car runs 10.20 on the track and you drive it on the street. Make changes and drive it on the street and it feels the same. Take it to the track and the changes result in it going 10 flat. You think wow......wouldn't have guessed that pulling up to the ET shack
69 Dart GTS A4 Silver All steel, flat factory hood, 3360race weight 418 BPE factory replacement headed stroker, 565 lift solid cam, footbrake street/strip car Best so far, 10.32 1/4 1.41 best 60 foot 6.56 at 104.17
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Re: camshaft lobe sep
[Re: CSK]
#2702341
09/30/19 06:30 PM
09/30/19 06:30 PM
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Joined: Jan 2003
Posts: 14,539 So. Burlington, Vt.
fast68plymouth
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I Live Here
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So. Burlington, Vt.
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I used to chase this stuff around but these days I use 112 in all of my street stuff with 4 degrees of advance. I don't even think about it anymore. Maybe I'm leaving peak power on the table but I don't care. 112 in at 108 works great on pump gas street engines, especially with EFI. 112 lsa is 112 lsa , no matter how much you advance the cam That’s true....... but it’s installed at some ICL.
68 Satellite, 383 with stock 906’s, 3550lbs, 11.18@123 Dealer for Comp Cams/Indy Heads
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Re: camshaft lobe sep
[Re: fast68plymouth]
#2702363
09/30/19 07:32 PM
09/30/19 07:32 PM
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Joined: Aug 2011
Posts: 2,905 Pattison Texas
CSK
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master
Joined: Aug 2011
Posts: 2,905
Pattison Texas
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I used to chase this stuff around but these days I use 112 in all of my street stuff with 4 degrees of advance. I don't even think about it anymore. Maybe I'm leaving peak power on the table but I don't care. 112 in at 108 works great on pump gas street engines, especially with EFI. 112 lsa is 112 lsa , no matter how much you advance the cam That’s true....... but it’s installed at some ICL. True,
1968 Charger COLD A/C Hilborn EFI 512ci 9.7 compression, Stealth heads, 4.10 gear A518 ODtrans 4100lb,10.93 full street car trim 2020 T/A 392 Stock 11.79 @ 114.5
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