LS Build: In Progress
04-06-2019 | 12:22 AM
#211
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Joined: Nov 2004
Posts: 14,068
Likes: 3,668
From: On A Dirt Floor
I'm glad we are talking about this. Can you PM me with .100" and .200" durations and seat durations for both intake and exhaust lobes ?
You may just have one of those funk azz potatoe in the tailpipe cams.that I mentioned running into above...Post #203..that are near impossible to tune right.....and flat line....just maybe.....we'll see....
You may just have one of those funk azz potatoe in the tailpipe cams.that I mentioned running into above...Post #203..that are near impossible to tune right.....and flat line....just maybe.....we'll see....
Last edited by SB; 04-06-2019 at 12:27 AM.
04-06-2019 | 12:48 AM
#212
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Joined: Jan 2016
Posts: 493
Likes: 17
From: San Tan Valley AZ
I'm glad we are talking about this. Can you PM me with .100" and .200" durations and seat durations for both intake and exhaust lobes ?
You may just have one of those funk azz potatoe in the tailpipe cams.that I mentioned running into above...Post #203..that are near impossible to tune right.....and flat line....just maybe.....we'll see....
You may just have one of those funk azz potatoe in the tailpipe cams.that I mentioned running into above...Post #203..that are near impossible to tune right.....and flat line....just maybe.....we'll see....
04-06-2019 | 08:06 AM
#213
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Joined: Jul 2004
Posts: 11,332
Likes: 73
From: chicago
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.
'
I am currently building (4) LS engines for a twin 28 Eliminator Daytona Tall Deck and 32 Sunsation Dominator. Figured I would let the cat out of the bag for future reference as a go to for people that attempt this. These engines will have prak torque at about 5000 and peak power at 6200. Roughly 625hp 600tq and make a 525efi look like a fool the entire powerband. We will be rev limiting them at 6200rpm. Remember these are not bbc and can easily sustain that rpm for hours on end.
04-06-2019 | 08:06 AM
#214
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Joined: Jul 2004
Posts: 11,332
Likes: 73
From: chicago
NightHawk LS 408 Dyno Run
RPM Torque (Ft.-Lbs.) HP3600 466.8 340.03700 473.5 355.3
3800 494.7 374.9
3900 508.8 391.4
4000 516.8 407.8
4100 524.6 426.1
4200 534.9 443.1
4300 539.7 463.0
4400 543.0 482.5
4500 548.6 496.8
4600 552.8 510.1
4700 554.0 522.8
4800 554.9 535.3
4900 555.0 546.8
5000 555.5 558.5
5100 555.6 570.0
5200 555.0 580.7
5300 552.0 588.5
5400 549.8 594.7
5500 547.1 600.5
5600 544.9 605.6
5700 540.0 609.0
5800 537.3 611.0
5900 532.6 612.4
6000 527.5 619.5
6100 524.2 623.7
6200 520.2 625.8
6300 511.9 628.6
6400 508.4 629.0
6500 502.9 629.5
6600 489.4 628.6
6700 479.7 625.3
6800 472.7 623.3
'
'
Last edited by MILD THUNDER; 04-06-2019 at 08:10 AM.
04-06-2019 | 08:18 AM
#215
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Joined: Jul 2004
Posts: 11,332
Likes: 73
From: chicago
If your engine made 549HP at 6200 with 30* of timing, Id say thats not too shabby for a stock LS3 headed 408ci. That VE% is pretty good for what it is.
One common thing we in the marine world often are used to , is fairly poor VE numbers, fairly high BSFCs, and fairly low HP to ci ratios. The LS guys poo poo our big blocks for that. '
Your engine made 1.34Hp per ci. Thats pretty good. Might say, well it makes a 525EFI look like a fool. Sure, the 525 only makes around 1.09hp per ci. However, the 525EFI, is also 8.75:1, and makes that 1.09HP per ci, about 1000 RPM lower than that LS. Now, build a 502ci, with 10.8:1 compression, custom cam , and spin it to 6200rpm. At 1.34hp per ci, that would be 672hp. Really not a tough feat for a 502 with almost 11:1 compression. With a 4" stroke, decent valvetrain parts , that 502 will live a long time turning 6200rpm. Its been done many times. The end of the day, the LS engine has many nice features from a design standpoint. But its not magic. You still need to move X amount of air, to make X amount of HP. That is why the big block chevy is still a favorite in many forms of motorsports today, from marine, to drag racing, truck pulling, or the guy who simply likes blowing his tires off thru the first 4 gears on a saturday night.
One common thing we in the marine world often are used to , is fairly poor VE numbers, fairly high BSFCs, and fairly low HP to ci ratios. The LS guys poo poo our big blocks for that. '
Your engine made 1.34Hp per ci. Thats pretty good. Might say, well it makes a 525EFI look like a fool. Sure, the 525 only makes around 1.09hp per ci. However, the 525EFI, is also 8.75:1, and makes that 1.09HP per ci, about 1000 RPM lower than that LS. Now, build a 502ci, with 10.8:1 compression, custom cam , and spin it to 6200rpm. At 1.34hp per ci, that would be 672hp. Really not a tough feat for a 502 with almost 11:1 compression. With a 4" stroke, decent valvetrain parts , that 502 will live a long time turning 6200rpm. Its been done many times. The end of the day, the LS engine has many nice features from a design standpoint. But its not magic. You still need to move X amount of air, to make X amount of HP. That is why the big block chevy is still a favorite in many forms of motorsports today, from marine, to drag racing, truck pulling, or the guy who simply likes blowing his tires off thru the first 4 gears on a saturday night.
Last edited by MILD THUNDER; 04-06-2019 at 08:28 AM.
04-06-2019 | 08:32 AM
#217
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Joined: Jan 2006
Posts: 3,854
Likes: 786
From: St. Pete Beach, FL
If your engine made 549HP at 6200 with 30* of timing, Id say thats not too shabby for a stock LS3 headed 408ci. That VE% is pretty good for what it is.
One common thing we in the marine world often are used to , is fairly poor VE numbers, fairly high BSFCs, and fairly low HP to ci ratios. The LS guys poo poo our big blocks for that. '
Your engine made 1.34Hp per ci. Thats pretty good. Might say, well it makes a 525EFI look like a fool. Sure, the 525 only makes around 1.09hp per ci. However, the 525EFI, is also 8.75:1, and makes that 1.09HP per ci, about 1000 RPM lower than that LS. Now, build a 502ci, with 10.8:1 compression, custom cam , and spin it to 6200rpm. At 1.34hp per ci, that would be 672hp. Really not a tough feat for a 502 with almost 11:1 compression. With a 4" stroke, decent valvetrain parts , that 502 will live a long time turning 6200rpm. Its been done many times. The end of the day, the LS engine has many nice features from a design standpoint. But its not magic. You still need to move X amount of air, to make X amount of HP. That is why the big block chevy is still a favorite in many forms of motorsports today, from marine, to drag racing, truck pulling, or the guy who simply likes blowing his tires off thru the first 4 gears on a saturday night.
One common thing we in the marine world often are used to , is fairly poor VE numbers, fairly high BSFCs, and fairly low HP to ci ratios. The LS guys poo poo our big blocks for that. '
Your engine made 1.34Hp per ci. Thats pretty good. Might say, well it makes a 525EFI look like a fool. Sure, the 525 only makes around 1.09hp per ci. However, the 525EFI, is also 8.75:1, and makes that 1.09HP per ci, about 1000 RPM lower than that LS. Now, build a 502ci, with 10.8:1 compression, custom cam , and spin it to 6200rpm. At 1.34hp per ci, that would be 672hp. Really not a tough feat for a 502 with almost 11:1 compression. With a 4" stroke, decent valvetrain parts , that 502 will live a long time turning 6200rpm. Its been done many times. The end of the day, the LS engine has many nice features from a design standpoint. But its not magic. You still need to move X amount of air, to make X amount of HP. That is why the big block chevy is still a favorite in many forms of motorsports today, from marine, to drag racing, truck pulling, or the guy who simply likes blowing his tires off thru the first 4 gears on a saturday night.
04-06-2019 | 08:39 AM
#218
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Joined: Jul 2004
Posts: 11,332
Likes: 73
From: chicago
One thing I have yet to see, is how the LS will stand up to offshore abuse. Meaning, in a big offshore that runs in BIG water, where the crankshaft is seeing tremendous shock loading from props coming in and out of the water, trying to twist the crankshaft out of the block. Flat water runs, dyno runs are one thing, a 41 Apache gettin it in big water with some saccenti like throttling going on, is another.
04-06-2019 | 10:57 AM
#219
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Joined: Jan 2016
Posts: 493
Likes: 17
From: San Tan Valley AZ
If your engine made 549HP at 6200 with 30* of timing, Id say thats not too shabby for a stock LS3 headed 408ci. That VE% is pretty good for what it is.
One common thing we in the marine world often are used to , is fairly poor VE numbers, fairly high BSFCs, and fairly low HP to ci ratios. The LS guys poo poo our big blocks for that. '
Your engine made 1.34Hp per ci. Thats pretty good. Might say, well it makes a 525EFI look like a fool. Sure, the 525 only makes around 1.09hp per ci. However, the 525EFI, is also 8.75:1, and makes that 1.09HP per ci, about 1000 RPM lower than that LS. Now, build a 502ci, with 10.8:1 compression, custom cam , and spin it to 6200rpm. At 1.34hp per ci, that would be 672hp. Really not a tough feat for a 502 with almost 11:1 compression. With a 4" stroke, decent valvetrain parts , that 502 will live a long time turning 6200rpm. Its been done many times. The end of the day, the LS engine has many nice features from a design standpoint. But its not magic. You still need to move X amount of air, to make X amount of HP. That is why the big block chevy is still a favorite in many forms of motorsports today, from marine, to drag racing, truck pulling, or the guy who simply likes blowing his tires off thru the first 4 gears on a saturday night.
One common thing we in the marine world often are used to , is fairly poor VE numbers, fairly high BSFCs, and fairly low HP to ci ratios. The LS guys poo poo our big blocks for that. '
Your engine made 1.34Hp per ci. Thats pretty good. Might say, well it makes a 525EFI look like a fool. Sure, the 525 only makes around 1.09hp per ci. However, the 525EFI, is also 8.75:1, and makes that 1.09HP per ci, about 1000 RPM lower than that LS. Now, build a 502ci, with 10.8:1 compression, custom cam , and spin it to 6200rpm. At 1.34hp per ci, that would be 672hp. Really not a tough feat for a 502 with almost 11:1 compression. With a 4" stroke, decent valvetrain parts , that 502 will live a long time turning 6200rpm. Its been done many times. The end of the day, the LS engine has many nice features from a design standpoint. But its not magic. You still need to move X amount of air, to make X amount of HP. That is why the big block chevy is still a favorite in many forms of motorsports today, from marine, to drag racing, truck pulling, or the guy who simply likes blowing his tires off thru the first 4 gears on a saturday night.
Last edited by mggdoors; 04-06-2019 at 11:41 AM.
04-06-2019 | 11:00 AM
#220
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Joined: Jan 2016
Posts: 493
Likes: 17
From: San Tan Valley AZ
I really dont understand the "LS CRAZE". That engine platform came out 22 years ago. Its not exactly some "NEW" technology. Its a great engine, that had some design improvements over the old small block engines. Sure they have made some great engines evolving from the early LS1. Theres more technology into a 4 cylinder Honda engine. Its a pushrod V8.
One thing I have yet to see, is how the LS will stand up to offshore abuse. Meaning, in a big offshore that runs in BIG water, where the crankshaft is seeing tremendous shock loading from props coming in and out of the water, trying to twist the crankshaft out of the block. Flat water runs, dyno runs are one thing, a 41 Apache gettin it in big water with some saccenti like throttling going on, is another.
One thing I have yet to see, is how the LS will stand up to offshore abuse. Meaning, in a big offshore that runs in BIG water, where the crankshaft is seeing tremendous shock loading from props coming in and out of the water, trying to twist the crankshaft out of the block. Flat water runs, dyno runs are one thing, a 41 Apache gettin it in big water with some saccenti like throttling going on, is another.
