unless someone can explain the numbers on each and break it down to me as to where the big difference between them lies/
I can try that;Not as good as Wrmy,
but I can try. Adjust your screen size so that this line just fits on one line. .....
What Ima gonna do is line 'em with all durations included so you can see what your getting, then we'll talk about what the numbers mean.
1:268/268/110/Ica of 60/120comp/112power/48olap@40Effective/218@.050
2:269/269/112/Ica 65.5/114.5 comp/112.5 power/45 olap@43E/213@.050
Firstly; Looking at just the .050 and lift numbers, the clear choice for me would be the first cam with 218*
Secondly; what Rusty said; single pattern cams, for your combo, are not the best choice. Those are mostly open-header, hi-flow-head choices. Rusty already mentioned why in Post #7.
Thirdly; the 112LSA is not the best choice either compared to a 110, because, take a look; it steals compression degrees and rolls them into overlap. Your combo cannot afford to give up compression degrees. In fact, at your elevation, you need a buncha more compression degrees, or just more compression period.
Fourthly; the power is in the Duration @.050. #1 has 5* more than #2, which should make it the clear choice for power. But#1 also has 3* less effective overlap, so that muddies the picture. But #1 also has 5.5* more compression duration, so the cylinder pressure will be higher at ALL TIMES, but specifically should make more power.
Fifthly; ; Power extraction is a wash and surprisingly is pretty generous, owing to the single-pattern cam.
Sixth; and this is very important; Area under the curve. Wyrmrider mentioned this in his typical, gentle voice. Since the data you supplied does not include these numbers, I cannot speak to that. Furthermore, since both of these cams are such poor choices for your combo, I wouldn't waste time searching it out.
However; the correct response to Wyrmrider's offer would have been something like; "tell me more", or what do you mean?"
Seventh; As I have already previously detailed, with either of these cams, your cylinder pressure and VP will be so low, as to be laughable, and off the line with your chosen combo, as Rusty so eloquently said; "will suck".
In case you forgot, I will post up the pressures again
Cam #1, Ica of 60*
Static compression ratio of 8.5:1.
Effective stroke is 2.88 inches.
Your dynamic compression ratio is 7.03:1 .
Your dynamic cranking pressure is 125.26 PSI.
V/P (Volume to Pressure Index) is 109
Cam #2, Ica of 65.5
Static compression ratio of 8.5:1.
Effective stroke is 2.75 inches.
Your dynamic compression ratio is 6.76:1 .
Your dynamic cranking pressure is 118.36 PSI.
V/P (Volume to Pressure Index) is 98
This comparison clearly shows cam 1 to be the winner as it posts a VP of 109 compared to 98 for the second.
BUT
I can guarantee you that VPs this low, suck; both of them.
You want to be up around 140 or better, but at your elevation, with your unverified Scr of 8.5, it's not ever gonna happen no matter how small a cam you slip in there. Not 140.
But at 10.7, you can make mid 140s happen, but not with iron heads; the pressure gets to be too high, which even on best gas, leads to detonation which must be avoided no matter what.
,
Here is an iron-headed engine you can build, but your chambers will have to be just right, and you will have to feed it best gas of 91 or better
Static compression ratio of 10.7:1.
Ica of 66*
Effective stroke is 2.79 inches.
Your dynamic compression ratio is 8.56:1 .
Your dynamic cranking pressure is 165.42 PSI.
V/P (Volume to Pressure Index) is 139, see this VP here? 139 is nice
Check this one out, for aluminum heads
Static compression ratio of 11.5:1.
Ica of 66*,aluminum heads
Effective stroke is 2.79 inches.
Your dynamic compression ratio is 9.18:1 .
Your dynamic cranking pressure is 182.15 PSI. Burns 87E10 for me
V/P (Volume to Pressure Index) is 153; this is sooooo Sweet!
But in all honesty, once you have the pressure and VP numbers where they need to be; a cam this big is ridiculous to run with your stall and gears.
Lessee, you could go down at least 2 cam sizes, and pull the compression back too;
check this out!
Static compression ratio of 10.8:1.
Ica of 56*,aluminum heads
Effective stroke is 2.97 inches.
Your dynamic compression ratio is 9.13:1 .
Your dynamic cranking pressure is 180.79 PSI.
V/P (Volume to Pressure Index) is 162; check this out; What a ripper! When is less more? I dropped the Scr from 11.5 to 10.7, but the VP climbed from 153 to 162 Shazzam. That is what the 10* earlier closing intake can do for you; 66 compared to 56*
This should break-loose 275s at ~50 mph, in second gear, with just a foot-stomp; yes with your 3.40 gears, and 2200stall.
Now; you might be asking; what cam might have an Ica of 56*.
Glad you asked.
Here is a theoretical cam I just made up for you;
260/268/108/Ica of 56/124* comp/116 power/48*olap@48Effective
This will make the Pressure and VP you need at an easy to build 10.8 Scr.
Ok so now you might be wondering about the .050 numbers. Well that will depend on what type of cam this is and who is grinding it.
As for me, I would make it a solid lifter type , because it will make an easy 15/20 horsepower more. But with the cylinder pressure now taken care of, you can afford to make it a Hydro. In which case the ramps are gonna vary from around 48 to 44, so this makes your intake durations @ .050s drop in at around 212 to 216, and that is perfect; the 212 power peaks at about 4600, and the 216 at maybe 4800.
I choose the 108LSa to make the 44* of overlap, so your headers can put their stamp on the power curve. This makes the power curve a lil taller at the expense of width. But in the case I am working towards, we don't care cuz this stinking 360 here, is already a tire fryer, and it's just a 1.5/2 gear run to 60mph, with those 3.40s (and 27" tires) getting you, in second gear, 60@3700@ zero-slip (perhaps as high as 4400 at 20% slip), very close to the power-peak. Shazzam! This indicates that if you wanted to, you could go to the next smaller cam, or a cam with longer ramps.
However, I feel, that this 260* cam I outlined is already pretty small.
With the engine now pulling like a freightrain at WOT, the PT (Part-Throttle) will also be extremely strong with that 162VP being the witness of it. You will be having so much fun, you will want to drive it everywhere all the time. And so;
finally, this cam sports 116* of power extraction and an effective stroke of 2.79.. Together with 3.40 gears,27" tires,and 65=2750rpm@zero slip, there exists a potential to pull some pretty good mpgs out of her.
So now you can
drive it everywhere all the time.
Ok the final witness;
I already built a combo like this, but with a cam one size bigger, because I am at a lower than you, 930 ft elevation. I ran it with a 4-speed,27s, and 3.55s, mostly.
mine looked like this;
Static compression ratio of 10.7:1.
Ica of 59 @930ft elevation
Effective stroke is 2.91 inches.
Your dynamic compression ratio is 8.88:1 .
Your dynamic cranking pressure is 182.15 PSI.
V/P (Volume to Pressure Index) is 163
It ran on 87E10 with full timing. It went 12.9@106, on street tires and street-tune. I showed up, I ran it, I went home. I used a slow-ramp cam of 223/230/110+2.
I cannot begin to tell you how much fun this combo was.
Happy HotRodding
