LS Build: In Progress
#221
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From: San Tan Valley AZ
#222
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From: On A Dirt Floor
The cam card just shows .050" durations. Also shows intake lobe area to be a little larger than exhaust. Does not mean a ton ,, yet, lobe info will show more.
Again,looking for seat, .100" and .200". This will be found in the master lobe catalog.
Let me know when you get this. Thanks.
#223
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From: San Tan Valley AZ
Was looking at the "AERA NIGHTHAWK " LS build just now . '
408ci 4.03x4.00
CNC ported trick flow heads
11.69:1 compression
243/251 .624/.624 114 LSA
Engine made 629HP at 6500RPM.
Your engine has almost a full point less compression, STOCK cylinder heads, 6* less intake duration, 14* less exhaust duration, same bore and stroke. Im just not seeing the original claim that this combo would make 625hp by 6000rpm, with the ingredients it has. The power seems to be fairly in the ballpark for what it is.
'
408ci 4.03x4.00
CNC ported trick flow heads
11.69:1 compression
243/251 .624/.624 114 LSA
Engine made 629HP at 6500RPM.
Your engine has almost a full point less compression, STOCK cylinder heads, 6* less intake duration, 14* less exhaust duration, same bore and stroke. Im just not seeing the original claim that this combo would make 625hp by 6000rpm, with the ingredients it has. The power seems to be fairly in the ballpark for what it is.
'
#224
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From: San Tan Valley AZ
The cam card just shows .050" durations. Also shows intake lobe area to be a little larger than exhaust. Does not mean a ton ,, yet, lobe info will show more.
Again,looking for seat, .100" and .200". This will be found in the master lobe catalog.
Let me know when you get this. Thanks.
#225
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From: taxachusetts
#227
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From: chicago
Will the cam i currently have make those numbers? Probably not. But one that note you will notice I changed paths on the cam after that post to prevent the need for dry exhaust and avoid reversion. I do see it making 570-580 which I am ok with. look up some dyno pulls on an ls3/l92 and you will see that NONE of them fall off on the power like mine currently is around 5200. When we clean that up results will be alot more impressive. In the mean time they are just pineapples. A good example to look at is a ct525 ls3 factory gm crate engine. 6.2 liters cranking out 540-550 with stock heads and a little 226/236 cam. Now Imagine that with 408 cubes and a bigger cam. I would say I should definitley be making a bunch more power than that engine eveywhere, which currently I am not.
Im still not sure why you thought you would make 625hp at 6200, when that engine is similarly specd, just less cubic inch, but only makes 533hp at 6600.
theres much smarter guys than me on this thread, just seems to me if 625 horse power is what you want, you need better heads , more cam, more rpm.
Of course youre limited by reversion/exhaust. Thats where heads would help. Less duration needed , when you have heads that flow really well. Stock LS3 heads dont exactly flow very well. My 392 Hemi in my challenger makes 485hp at 6000rpm. Sae power with all accessories, factory exhaust, etc. On a typical dyno, with long tube headers, its easily over 500hp. The cam is fairly short duration, but the apache heads flow like an aftermarket big block chevy head.
I follow you with the single pattern cam concept, as it can help build torque in the lower rpm range. I remember brian tooley talking about this topic. In his testing, he found the crossover point, where the dual pattern cam on a LS started making more power, was much lower than most think. I forget the exact number, but wanna say it was in the 2500-3000rpm range. With such a poor intake to exhaust flow ratio on the stock LS3 heads, i just dont think its single pattern worthy. Now if they had excellent exhaust ports, it might be worth it.
Please dont take offense to my or others criticism towards your combo. Its just shop talk. Looking forward to your next move and its results.
#228
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From: San Tan Valley AZ
Yes, the CT3 makes 533hp, at 6600rpm, with a 226/236 cam. It also has a significantly smaller stroke crank. The cam that pulls to 6600 in that engine, wont be the same cam that will pull to 6600 in yours. You need more cam to get to 6600.
Im still not sure why you thought you would make 625hp at 6200, when that engine is similarly specd, just less cubic inch, but only makes 533hp at 6600.
theres much smarter guys than me on this thread, just seems to me if 625 horse power is what you want, you need better heads , more cam, more rpm.
Of course youre limited by reversion/exhaust. Thats where heads would help. Less duration needed , when you have heads that flow really well. Stock LS3 heads dont exactly flow very well. My 392 Hemi in my challenger makes 485hp at 6000rpm. Sae power with all accessories, factory exhaust, etc. On a typical dyno, with long tube headers, its easily over 500hp. The cam is fairly short duration, but the apache heads flow like an aftermarket big block chevy head.
I follow you with the single pattern cam concept, as it can help build torque in the lower rpm range. I remember brian tooley talking about this topic. In his testing, he found the crossover point, where the dual pattern cam on a LS started making more power, was much lower than most think. I forget the exact number, but wanna say it was in the 2500-3000rpm range. With such a poor intake to exhaust flow ratio on the stock LS3 heads, i just dont think its single pattern worthy. Now if they had excellent exhaust ports, it might be worth it.
Please dont take offense to my or others criticism towards your combo. Its just shop talk. Looking forward to your next move and its results.
Im still not sure why you thought you would make 625hp at 6200, when that engine is similarly specd, just less cubic inch, but only makes 533hp at 6600.
theres much smarter guys than me on this thread, just seems to me if 625 horse power is what you want, you need better heads , more cam, more rpm.
Of course youre limited by reversion/exhaust. Thats where heads would help. Less duration needed , when you have heads that flow really well. Stock LS3 heads dont exactly flow very well. My 392 Hemi in my challenger makes 485hp at 6000rpm. Sae power with all accessories, factory exhaust, etc. On a typical dyno, with long tube headers, its easily over 500hp. The cam is fairly short duration, but the apache heads flow like an aftermarket big block chevy head.
I follow you with the single pattern cam concept, as it can help build torque in the lower rpm range. I remember brian tooley talking about this topic. In his testing, he found the crossover point, where the dual pattern cam on a LS started making more power, was much lower than most think. I forget the exact number, but wanna say it was in the 2500-3000rpm range. With such a poor intake to exhaust flow ratio on the stock LS3 heads, i just dont think its single pattern worthy. Now if they had excellent exhaust ports, it might be worth it.
Please dont take offense to my or others criticism towards your combo. Its just shop talk. Looking forward to your next move and its results.
Last edited by mggdoors; 04-06-2019 at 07:08 PM.
#229
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Joined: Feb 2009
Posts: 8,356
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From: NW Michigan
Good point MT with superior flowing heads less duration necessary. Good example is Valakos 565 ci peaks hp at 6K with a little 236/244 duration cam. Running solid rollers to boot. Makes complete sense.
Endeavor32 and I took a not so cozy temp lake MI ride today in his 37 AT but did some prop changing and had fun regardless. Mike said my face was redder than my maga hat. Lol....
Regardless keep at it doug and I know you will. Nothing ventured nothing gained. Get some more deposits for doors and get some heads coming. You might even be able to get away with your existing cams. Good thread.
Endeavor32 and I took a not so cozy temp lake MI ride today in his 37 AT but did some prop changing and had fun regardless. Mike said my face was redder than my maga hat. Lol....
Regardless keep at it doug and I know you will. Nothing ventured nothing gained. Get some more deposits for doors and get some heads coming. You might even be able to get away with your existing cams. Good thread.
Last edited by getrdunn; 04-06-2019 at 07:49 PM.



