Opinions on this cam for a 360

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That’s a loaded question Dan. Not enough information.
It’s kind of like, tomorrows forecast is 100% clear skies, is there any chance whatsoever that the color Blue 3 will appear on the 5 O’clock horizontal at 3pm if the humidity and suns pitch is in line for the day or does the air temperature have a play in it?
 
Dan the man said:
Is a tighter lsa better for low to midrange torque? I'm not worried about idle quality. I haven't got a car yet but I'm trying to get a decent idea of the route I want to take. I doubt that the engine will ever see over 5000 rpm's
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Why only 5000 rpm? If your main interest is just low to midrange, a stock 360 magnum might be a good choice. No sense in building an engine that makes power past the point of where you are willing to take it.
 
forphorty said:
Why only 5000 rpm? If your main interest is just low to midrange, a stock 360 magnum might be a good choice. No sense in building an engine that makes power past the point of where you are willing to take it.
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Only 5000 rpm's because it will be for cruising only, no racing
 
Dan the man said:
I can understand that. Would the tighter LSA still have a rough idle if the duration at 0.050" is under 220*?
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How tight is tight? The Summit 216 at .050 with a 110 LSA in my 318 sounds nearly stock.
 
rumblefish360 said:
That’s a loaded question Dan. Not enough information.
It’s kind of like, tomorrows forecast is 100% clear skies, is there any chance whatsoever that the color Blue 3 will appear on the 5 O’clock horizontal at 3pm if the humidity and suns pitch is in line for the day or does the air temperature have a play in it?
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That makes sense. I think that it's best to wait till I actually have the car in my driveway
 
Dan the man said:
That makes sense. I think that it's best to wait till I actually have the car in my driveway
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Grab a 5.9, give it headers, a 750 carb on top of a RPM & a vacuum advance distributor. Use a A-500 transmission & 3.55’s spinning 26-27 inch tires. If you don’t like the performance of it when you get your car…….. PM me on camshafts that “I” would use. From there, you can ask 10,000 questions and drag your feet on a cam purchase until you feel good about the research on the cam you pick.

:thumbsup:
 
Dan the man said:
Be a cam to look into. How's it for low to midrange torque and throttle response
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In a 318, a little soft on the bottom with a stock converter and pulls past 5500. Of course it would be stronger down low in a 360. If you're just cruising around, you would money ahead with just a stock 360, recurved distributor, 4 barrel and dual exhaust.
 
forphorty said:
In a 318, a little soft on the bottom with a stock converter and pulls past 5500. Of course it would be stronger down low in a 360. If you're just cruising around, you would money ahead with just a stock 360, recurved distributor, 4 barrel and dual exhaust.
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This really has been the most spoke of thing to do.
 
Posts #23 & 25.
Dan.

[1] All else being equal, for cams in this duration range, a tighter LSA will have a rougher idle & less vacuum.
[2] Waaaaaaaaaaay before LSA was a glint in anybody's eye, in the 1970s', cam grinder Sig Erson had this note in his cam catalog, under Cam Sense:
'' The camshaft with tighter lobe centres will always produce more power in the mid range than a cam using the same profile & wide lobe center...
[3] He also worked with, & was friends with, D. Vizard
 
Bewy said:
[2] Waaaaaaaaaaay before LSA was a glint in anybody's eye, in the 1970s', cam grinder Sig Erson had this note in his cam catalog, under Cam Sense:
'' The camshaft with tighter lobe centres will always produce more power in the mid range than a cam using the same profile & wide lobe center...
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Yep! There is a question with some that there is to far you can go with it. I’ve noted diminishing returns as the LSA reaches a certain point. There is also how much you can live with a racer idle.
 
For smoother idle:

Vizard says to reduce duration, not widen the LSA.

His SBC book has two pages of recommended cams.

Example: Street & tow would be smooth idle.
434 [ stroker ]
400
383 [ stroker]
350
327
302.

All have 207 @ 050 duration. What is different for each engine size is LSA [ overlap ]. Starting with the largest engine: 104, 105, 106, 108, 109, 110.
 
The world is used to seeing wider centerlines for this easier idle. Factory, magazines, TV shows, etc….
 
If it’s a choice between an ideal cam that had a tight LSA and I was concerned about vacuum for my power brakes and it required spreading the LSA, I’d convert to manual brakes. I’d convert to manual brakes regardless. Power brakes and steering....pfft. And run the idle at 1000 or so Lube that cam. What’s this attraction with low idle anway? Don’t bother answering. I know. Idle quality schmuality :lol:
 
kdeboy said:
Looking at a solid FT cam for an A body. Heads would be TF 190's, 10-10.5:1 compression ratio, 4.30 (or so) rear end, 3500 (or so) stall speed converter. Primarily street driven, needs to run on 91 pump gas but I want it to be quick. Looking at this one b/c all of their street cams have a wider LSA.
Comp Cams 20-629-5
Intake: 269 adv, 243 @ .050, 0.549 lift
Exhaust: 273 adv, 247 @ .050, 0.560 lift
LSA: 108

I know it's listed as an oval track cam, I was thinking that "might" mean it's a little more useable for street use than a drag race cam
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According to David Vizard's LSA formula, considering a stock stroke and 2.02" intake valves and using the Chevy 128 number, your ideal LSA would be 103°. Might be a little lumpy, but a cam with 10°less duration and that LSA would likely give the same or more performance across the rev range.
Now DV says, "I don't have an opinion, I have a dyno". I don't know how many dyno tests David has for his resume, but 10,000 probably does not cover it.
David states you are better to be a degree too tight on LSA than a degree too wide. You could spec a cam LSA as long as they can grind it on a core without going through the hard surface. DV also recommends the extra hard surface on a Comp grind. Talk to them and mention DV and they probably will know exactly what you are referring to. In the end it is your dime. Consider this that DV also says, it costs the same to grind on the correct LSA as on the wrong LSA.
 
OK, this goes way back, but the 56 Plymouth Fury 303 poly had a cam with almost exactly the same duration and lift as the standard 277 poly cam, very mild, with less than .400 lift and duration at .050 probably less than 200 (244 advertised), but the Fury cam had a tighter lobe separation than the standard 277 cam for more power (in midrange, I assume).
 
Dale Davies said:
According to David Vizard's LSA formula, considering a stock stroke and 2.02" intake valves and using the Chevy 128 number, your ideal LSA would be 103°. Might be a little lumpy, but a cam with 10°less duration and that LSA would likely give the same or more performance across the rev range.
Now DV says, "I don't have an opinion, I have a dyno". I don't know how many dyno tests David has for his resume, but 10,000 probably does not cover it.
David states you are better to be a degree too tight on LSA than a degree too wide. You could spec a cam LSA as long as they can grind it on a core without going through the hard surface. DV also recommends the extra hard surface on a Comp grind. Talk to them and mention DV and they probably will know exactly what you are referring to. In the end it is your dime. Consider this that DV also says, it costs the same to grind on the correct LSA as on the wrong LSA.
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My math might be wrong
But I get 107.73
Using DV 128 formula?
Just Courious
 
Mopar69gts said:
My math might be wrong
But I get 107.73
Using DV 128 formula?
Just Courious
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I get the same:

LCA = 128 - (((CID/#-of-cylinders)/In-valve-diameter-in-inches) * 0.91)
LCA = 128 - (((360/8)/2.02) * 0.91)
LCA = 128 - ((45/2.02) * 0.91)
LCA = 128 - (22.28 * 0.91)
LCA = 128 - 20.27
LCA = 107.73

Close enough to 108 for me.
 

kdeboy said:
I get the same:

LCA = 128 - (((CID/#-of-cylinders)/In-valve-diameter-in-inches) * 0.91)
LCA = 128 - (((360/8)/2.02) * 0.91)
LCA = 128 - ((45/2.02) * 0.91)
LCA = 128 - (22.28 * 0.91)
LCA = 128 - 20.27
LCA = 107.73

Close enough to 108 for me.
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BTW, I like your choice of camshaft!
keep us posted after install please.
 
I have a 410 stroker and has a cam with a 112 LSA. it has 238/242 @610 lift on a roller hyd cam.
It makes 425 rear wheel HP . It idles happy at 850rpm but crack the acc pedal at any thing over 2500 rpm in second gear (manual) and it goes insane! I am 68 years young so did not want a lumpy pig to drive so went with a wide LSA and I am quite happy with how mild the car drives but produces over 530 HP at the flywheel. Every body comments how nice it idles and drives!
 
James Clews said:
I have a 410 stroker and has a cam with a 112 LSA. it has 238/242 @610 lift on a roller hyd cam.
It makes 425 rear wheel HP . It idles happy at 850rpm but crack the acc pedal at any thing over 2500 rpm in second gear (manual) and it goes insane! I am 68 years young so did not want a lumpy pig to drive so went with a wide LSA and I am quite happy with how mild the car drives but produces over 530 HP at the flywheel. Every body comments how nice it idles and
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What are the timing events on that cam? Heads, intake?
 
James Clews said:
I have a 410 stroker and has a cam with a 112 LSA. it has 238/242 @610 lift on a roller hyd cam.
It makes 425 rear wheel HP . It idles happy at 850rpm but crack the acc pedal at any thing over 2500 rpm in second gear (manual) and it goes insane! I am 68 years young so did not want a lumpy pig to drive so went with a wide LSA and I am quite happy with how mild the car drives but produces over 530 HP at the flywheel. Every body comments how nice it idles and drives!
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That's the Beauty of a Stroker right there!

I must admit I do like a Lumpy ldle.
Bullet is grinding a new cam for my
Stock stroke 340
Single pattern, Solid flat for a 904 lifter
239 @50, 536 lift, 108 Lsa.
This is their recommendation after describing what I was after.
More bottom end For my Driver
With a lumpy idle
Never sees more then 6 -6500
(This cam is an Ultradyne NF 70)
 
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