TR220 112 lsa vs TR220 114 lsa
10-31-2005, 08:48 PM
#41
[QUOTE=Sport Side]I've seen a back to back dyno comparison between a 112 and 114 seperation. The 114 lossed midrange torque and both camshafts peaked at relatively the same rpm.
You can't always follow those ancient rules of advance does this and, wide lobe seperation angles flatten out the torque curve. These ideas do not apply to every application.[QUOTE=Sport Side]
Going a little bit back of what Sportside said, is that why I feel that my truck starts to pull from 4300 rpm above? I told this to tiburon one time and he told me that maybe it has not been tuned for mid-range. It really sucks because sometimes I tend to race somebody for say on a 50 mph roll and my rpm is let's say at 3800, when I floor it, it feels kind of sluggish until it reaches to 4300 rpm
. Even though with the 3k stall, I thought it would be better to resize it to a 3800 so it wouldn't be that much far from 4300 rpm. I must say that I haven't dynotuned my truck, it was tuned on the road only. I have logged it with rgv sierra and readings say that it's running like in the high 10's air/fuel. Very rich I suppose. Maybe there's a little bit left in her. What do you guys think about all this? 
You can't always follow those ancient rules of advance does this and, wide lobe seperation angles flatten out the torque curve. These ideas do not apply to every application.[QUOTE=Sport Side]
Going a little bit back of what Sportside said, is that why I feel that my truck starts to pull from 4300 rpm above? I told this to tiburon one time and he told me that maybe it has not been tuned for mid-range. It really sucks because sometimes I tend to race somebody for say on a 50 mph roll and my rpm is let's say at 3800, when I floor it, it feels kind of sluggish until it reaches to 4300 rpm
. Even though with the 3k stall, I thought it would be better to resize it to a 3800 so it wouldn't be that much far from 4300 rpm. I must say that I haven't dynotuned my truck, it was tuned on the road only. I have logged it with rgv sierra and readings say that it's running like in the high 10's air/fuel. Very rich I suppose. Maybe there's a little bit left in her. What do you guys think about all this?
Last edited by La Chochita; 10-31-2005 at 09:03 PM.
10-31-2005, 09:19 PM
#42
Originally Posted by La Chochita
is that why I feel that my truck starts to pull from 4300 rpm above?
*EDIT* I somehow missed your A/F ratio the first time I read this...running pig rich will definitely be killin ya.
Last edited by budhayes3; 10-31-2005 at 09:47 PM.
10-31-2005, 09:32 PM
#43
great article notice how he emphasized cam selection importance for the aftermaket truck world
"For the first and most important half of the induction stroke the intake valve is opened farther by a cam with a tight LCA than one with a wide LCA. This produces a greater flow area as the piston starts to pull in a fresh charge."
Also he remarked about a cam with alot of overlap not liking backpressure. I noticed this when I first did my h/c swap I still had stock manifold y pipe cats and a 50 series blowmaster. I noticed a marginal increase up top when things started flowing and I had enough pressure built up to push the exhaust out. As soon as I fabbed up a ypipe, got rid of the cats, lt's and a cutout. It fealt like I gained 40+ rwhp and its was a more noticable improvement than even after I had done the h/c swap. Ill have the numbers to back it up soon. I really think alot of people leave a tremendous amount of power on the table with exhaust work, they throw in a cam-tune and expect it to run.
"For the first and most important half of the induction stroke the intake valve is opened farther by a cam with a tight LCA than one with a wide LCA. This produces a greater flow area as the piston starts to pull in a fresh charge."
Also he remarked about a cam with alot of overlap not liking backpressure. I noticed this when I first did my h/c swap I still had stock manifold y pipe cats and a 50 series blowmaster. I noticed a marginal increase up top when things started flowing and I had enough pressure built up to push the exhaust out. As soon as I fabbed up a ypipe, got rid of the cats, lt's and a cutout. It fealt like I gained 40+ rwhp and its was a more noticable improvement than even after I had done the h/c swap. Ill have the numbers to back it up soon. I really think alot of people leave a tremendous amount of power on the table with exhaust work, they throw in a cam-tune and expect it to run.
10-31-2005, 09:38 PM
#44
Going a little bit back of what Sportside said, is that why I feel that my truck starts to pull from 4300 rpm above? I told this to tiburon one time and he told me that maybe it has not been tuned for mid-range. It really sucks because sometimes I tend to race somebody for say on a 50 mph roll and my rpm is let's say at 3800, when I floor it, it feels kind of sluggish until it reaches to 4300 rpm . Even though with the 3k stall, I thought it would be better to resize it to a 3800 so it wouldn't be that much far from 4300 rpm. I must say that I haven't dynotuned my truck, it was tuned on the road only. I have logged it with rgv sierra and readings say that it's running like in the high 10's air/fuel. Very rich I suppose. Maybe there's a little bit left in her. What do you guys think about all this?
. Even though with the 3k stall, I thought it would be better to resize it to a 3800 so it wouldn't be that much far from 4300 rpm. I must say that I haven't dynotuned my truck, it was tuned on the road only. I have logged it with rgv sierra and readings say that it's running like in the high 10's air/fuel. Very rich I suppose. Maybe there's a little bit left in her. What do you guys think about all this?
I dont agree with the notion of trying to tune for a spot in the rpm range. You should be tuning for the mods that you have done, you tune around the cam not the reverse. Pick the mods then tune for them, if you want mid range power pick the mods that will support that particular goal.
just my .02
10-31-2005, 09:52 PM
#45
Originally Posted by 02sierraz71_5.3
great article notice how he emphasized cam selection importance for the aftermaket truck world
Also he remarked about a cam with alot of overlap not liking backpressure..
Also he remarked about a cam with alot of overlap not liking backpressure..
11-01-2005, 05:02 AM
#46
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La Chochita,
I wouldn't necessarily say that your problem is the lobe seperation angle. That camshaft on a 114 or 112 does not have much overlap. It could more than likely pass smog on either seperation. (-4* @ .05'' vs. -8* @ .05'')
Your problem is either the tune or just simply the wrong camshaft for your needs.
Have Dan fix your PE table to rougly 13.0:1 AFR @ w.o.t. and bump up your timing.
I wouldn't necessarily say that your problem is the lobe seperation angle. That camshaft on a 114 or 112 does not have much overlap. It could more than likely pass smog on either seperation. (-4* @ .05'' vs. -8* @ .05'')
Your problem is either the tune or just simply the wrong camshaft for your needs.
Have Dan fix your PE table to rougly 13.0:1 AFR @ w.o.t. and bump up your timing.
11-01-2005, 05:18 AM
#47
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I found the dyno graph I had mentioned that compared a 112* LSA to a 114*LSA. The 112 made roughly 4-8rwhp from 2300-4500 over a 114. Those gains are based off of what I can tell. The chart is not accurately labeled. Also, remember that were only talking about a small change in overlap. Now, when you take a camshaft that has a 116 seperation w/ 6* advance and tighten that to a 110* seperation installed straight up. You now have the same IVC point if duration has not changed and 12* more overlap at that given lift.
I'll see if I can post the dyno up this afternoon. I'm having some troubles with my computer.
I'll see if I can post the dyno up this afternoon. I'm having some troubles with my computer.
11-01-2005, 09:08 AM
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my a/f ratio was showing around 12.2 @ wot. and between 14 and 15 when slowly excellerating on the dyno. how good is this? don't know too much about a/f ratio. thanks... lance
11-01-2005, 09:33 AM
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Originally Posted by Sport Side
La Chochita,
I wouldn't necessarily say that your problem is the lobe seperation angle. That camshaft on a 114 or 112 does not have much overlap. It could more than likely pass smog on either seperation. (-4* @ .05'' vs. -8* @ .05'')
Your problem is either the tune or just simply the wrong camshaft for your needs.
Have Dan fix your PE table to rougly 13.0:1 AFR @ w.o.t. and bump up your timing.
I wouldn't necessarily say that your problem is the lobe seperation angle. That camshaft on a 114 or 112 does not have much overlap. It could more than likely pass smog on either seperation. (-4* @ .05'' vs. -8* @ .05'')
Your problem is either the tune or just simply the wrong camshaft for your needs.
Have Dan fix your PE table to rougly 13.0:1 AFR @ w.o.t. and bump up your timing.
11-01-2005, 11:02 AM
#50
I did not tune his truck eather and prefer not to say who did. I will leave it up to Ivan if he wants to say. This is what his PE table looks like:
1.284 1.284 1.284 1.284 1.284 1.345 1.345 1.345 1.355 1.394 1.41 1.452 1.488 1.459 1.459 1.459 1.459 1.459 1.459
And here is his VE Table
41 58 46 55 49 52 47 52 58 64 67 59 49 38 29 29 29 29 29 29
54 57 56 59 58 59 53 55 65 71 74 71 69 59 50 50 50 50 50 50
55 58 61 59 58 64 66 65 73 77 79 77 72 65 58 58 58 58 58 58
55 60 55 60 67 73 70 74 81 83 84 82 78 72 65 65 65 65 65 65
56 63 56 69 70 74 73 76 83 85 87 85 81 76 70 70 70 70 70 70
59 55 59 67 72 77 78 81 85 87 90 87 83 79 72 72 72 72 72 72
61 57 67 73 73 83 79 82 84 88 89 87 84 85 74 74 74 74 74 74
62 68 66 73 75 81 81 82 85 89 90 88 85 81 75 75 75 75 75 75
58 69 70 76 76 82 82 83 88 90 92 89 86 82 76 76 76 76 76 76
64 69 74 78 77 82 82 85 89 91 91 89 87 83 77 77 77 77 77 77
66 68 72 77 78 83 83 89 88 91 92 90 88 84 78 78 78 78 78 78
67 63 73 78 79 83 84 86 90 92 92 91 88 85 79 79 79 79 79 79
70 75 73 81 83 84 85 86 88 91 92 91 89 85 80 80 80 80 80 80
71 74 78 82 81 85 86 89 90 92 92 91 89 86 80 80 80 80 80 80
72 76 79 82 83 85 87 87 90 93 93 91 89 86 81 81 81 81 81 81
73 77 81 85 85 85 87 87 90 94 94 92 90 94 82 82 82 82 82 82
74 78 82 85 85 90 86 90 92 95 94 99 98 94 83 83 83 83 83 83
75 80 84 88 86 93 92 96 98 102 101 100 98 88 83 83 83 83 83
75 79 82 85 85 86 87 89 91 95 94 93 91 88 83 83 83 83 83 83
As you all can see, he shoud running very rich with these values. However, his 02 reading at WOT are in the 875-895 range. There is only one way to find out what his true A/F ratio is.
Dan as far as taking our trucks to the Dyno, maybe we should set a date and of us go
1.284 1.284 1.284 1.284 1.284 1.345 1.345 1.345 1.355 1.394 1.41 1.452 1.488 1.459 1.459 1.459 1.459 1.459 1.459
And here is his VE Table
41 58 46 55 49 52 47 52 58 64 67 59 49 38 29 29 29 29 29 29
54 57 56 59 58 59 53 55 65 71 74 71 69 59 50 50 50 50 50 50
55 58 61 59 58 64 66 65 73 77 79 77 72 65 58 58 58 58 58 58
55 60 55 60 67 73 70 74 81 83 84 82 78 72 65 65 65 65 65 65
56 63 56 69 70 74 73 76 83 85 87 85 81 76 70 70 70 70 70 70
59 55 59 67 72 77 78 81 85 87 90 87 83 79 72 72 72 72 72 72
61 57 67 73 73 83 79 82 84 88 89 87 84 85 74 74 74 74 74 74
62 68 66 73 75 81 81 82 85 89 90 88 85 81 75 75 75 75 75 75
58 69 70 76 76 82 82 83 88 90 92 89 86 82 76 76 76 76 76 76
64 69 74 78 77 82 82 85 89 91 91 89 87 83 77 77 77 77 77 77
66 68 72 77 78 83 83 89 88 91 92 90 88 84 78 78 78 78 78 78
67 63 73 78 79 83 84 86 90 92 92 91 88 85 79 79 79 79 79 79
70 75 73 81 83 84 85 86 88 91 92 91 89 85 80 80 80 80 80 80
71 74 78 82 81 85 86 89 90 92 92 91 89 86 80 80 80 80 80 80
72 76 79 82 83 85 87 87 90 93 93 91 89 86 81 81 81 81 81 81
73 77 81 85 85 85 87 87 90 94 94 92 90 94 82 82 82 82 82 82
74 78 82 85 85 90 86 90 92 95 94 99 98 94 83 83 83 83 83 83
75 80 84 88 86 93 92 96 98 102 101 100 98 88 83 83 83 83 83
75 79 82 85 85 86 87 89 91 95 94 93 91 88 83 83 83 83 83 83
As you all can see, he shoud running very rich with these values. However, his 02 reading at WOT are in the 875-895 range. There is only one way to find out what his true A/F ratio is.
Dan as far as taking our trucks to the Dyno, maybe we should set a date and of us go
Originally Posted by rgvsierra
no no, i did not tune the truck, i only logged it with my hp cable, i have seen a copy of his bin and the pe table has worse than stock settings. his 02's if i remember correctly were good, the only thing he needs to do is hit the dyno, i've been telling Tiburon and LaChochita to go, but they refuse to.. they are worried that they wont hit 300rwhp. lol.
Last edited by Tiburon; 11-01-2005 at 11:09 AM.