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Old 02-16-2016, 09:33 AM
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I think there are exceptions to the rule that blower cams need to be on a 114 to make power. I remember a buddy swithing from a 115lsa cam with an M4 procharger, to a 112lsa cam, and his torque numbers went thru the roof compared to the 115 cam, and the engine ran much better off boost
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Old 02-16-2016, 09:33 AM
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Originally Posted by Black Baja
Good point. I forgot it was boosted. In that case I would go with the 114.
It tends to widen the power band a bit and be less peaky from what I've seen.
[ATTACH=CONFIG]551085[/ATTACH]
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Old 02-16-2016, 09:40 AM
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Originally Posted by MILD THUNDER
I think there are exceptions to the rule that blower cams need to be on a 114 to make power. I remember a buddy swithing from a 115lsa cam with an M4 procharger, to a 112lsa cam, and his torque numbers went thru the roof compared to the 115 cam, and the engine ran much better off boost
Did the lobes stay the same and the split tightened up?
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Old 02-16-2016, 09:42 AM
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Originally Posted by MILD THUNDER
the engine ran much better off boost
Maybe that had something to do with more reversion in the intake manifold (overlap)?

My old cams were on a 112 and I saw a lot of carbon tracking inside the intake manifold. My exhaust sound changed a lot as well. The 112 had the perverbial AFR chirp at idle, while the 114 pops at idle. I don't think 2* degree's is going to change the world but my torque curve definitely got wider which might also have had more to do with the hydraulic roller but none the less, it worked out well.
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Old 02-16-2016, 09:52 AM
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Originally Posted by MILD THUNDER
I think there are exceptions to the rule that blower cams need to be on a 114 to make power. I remember a buddy swithing from a 115lsa cam with an M4 procharger, to a 112lsa cam, and his torque numbers went thru the roof compared to the 115 cam, and the engine ran much better off boost
Did the lobes stay the same and the split tightened up?
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Old 02-16-2016, 09:52 AM
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Originally Posted by Black Baja
Did the lobes stay the same and the split tightened up?
I cant recall the exact specs, but the lift was about same, split was about same, but duration moved down a bit. This combo was making 1260hp at 6000. Ill see if i have the dyno sheets from both setups tonight.

I know all bds blower cams are 110lsa. For gasoline that is, and chief engines in florida was using 110LSA cams as well on their blower motors. Supposedly the extra overlap helped cool down the exhaust valves by allowing a little more of the intake charge past the exhaust valve. Problem is effieciency and boost level goes down a bit, and you have to spin the blower a little harder.
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Old 02-16-2016, 10:00 AM
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Originally Posted by MILD THUNDER
I cant recall the exact specs, but the lift was about same, split was about same, but duration moved down a bit. This combo was making 1260hp at 6000. Ill see if i have the dyno sheets from both setups tonight.

I know all bds blower cams are 110lsa. For gasoline that is, and chief engines in florida was using 110LSA cams as well on their blower motors. Supposedly the extra overlap helped cool down the exhaust valves by allowing a little more of the intake charge past the exhaust valve. Problem is effieciency and boost level goes down a bit, and you have to spin the blower a little harder.
So it may have ended up with less overlap...
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Old 02-16-2016, 10:11 AM
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Originally Posted by Black Baja
So it may have ended up with less overlap...
Quite possible. I dont think the duration change was more than a couple degrees. This was also a 522 inch engine. That cam was from terry at custom cams i wanna say.

Marine kinetics did a cam for this engine when converted to roots and afr heads. It made 1020hp at 6700rpm with 10lbs of boost. Cam was a standard cam core .842 hyd lifter. Duration was 245/253 113LSA, with lift something like .697/681 or somethint like that. Ill have to dig up the cam card . Engines have dyno time only, so it will be intersting how they hold up in the boat. Kind of scary hearing and seeing some of the carnage with similar setups now.

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Old 02-16-2016, 10:40 AM
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Originally Posted by MILD THUNDER
Quite possible. I dont think the duration change was more than a couple degrees. This was also a 522 inch engine. That cam was from terry at custom cams i wanna say.

Marine kinetics did a cam for this engine when converted to roots and afr heads. It made 1020hp at 6700rpm with 10lbs of boost. Cam was a standard cam core .842 hyd lifter. Duration was 245/253 113LSA, with lift something like .697/681 or somethint like that. Ill have to dig up the cam card . Engines have dyno time only, so it will be intersting how they hold up in the boat. Kind of scary hearing and seeing some of the carnage with similar setups now.
and you can bet that i am a little nervous and worried about the longivity of these engines.
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Old 02-16-2016, 10:50 AM
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I'm with you on that bud.

Originally Posted by mike tkach
and you can bet that i am a little nervous and worried about the longivity of these engines.
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