12 Valve Conversion Help & Tips???
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From: Red Deer, Alberta
This "theory" has been dyno proven. Going to a 5" setup has no benefit and is actually a detriment to flow in the pipe. Its not so much the pulses, but you want lamilar flow, that being all the fluid is flowing in one direction in a straight line (the main reason we use mandrel bent pipes). The large pipe causes turbulence, especially at low flow ie. low rpm and then artifically causes "backpressure" or loss in the system. If you can get lamilar flow in the piping with little pressure loss, you actually get a scavenging effect and the flow increases in efficiency.
Most guys in the 600 club have compounds where the primary is a 5" outlet anyway.
Jamie, when you have the engine in your hands, call me.
Most guys in the 600 club have compounds where the primary is a 5" outlet anyway.
Jamie, when you have the engine in your hands, call me.
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From: Okotoks AB
This "theory" has been dyno proven. Going to a 5" setup has no benefit and is actually a detriment to flow in the pipe. Its not so much the pulses, but you want lamilar flow, that being all the fluid is flowing in one direction in a straight line (the main reason we use mandrel bent pipes). The large pipe causes turbulence, especially at low flow ie. low rpm and then artifically causes "backpressure" or loss in the system. If you can get lamilar flow in the piping with little pressure loss, you actually get a scavenging effect and the flow increases in efficiency.
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From: Red Deer, Alberta
You won't drool over it, It's a heap but a fun heap of.....
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From: Grande Prairie, AB Canada
I have five inch exhaust on my 5.9 and i dont have an issue. my pretty plain truck turned almost 500hp on the dyno with no much put into her, and loosing power to the 37 inch rubber and 6 inch lift. so you may all have your theories, but my truck had it on when i bought it, it has unique sound that no one else has in town, and when i leave you all in my black smoke thats all that matters to me!! because in the end its gonna be a girl in a sweet cummins diesel thats going to kick all your butts anyways!!!! lol later!
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cheap motor that works nails
cheap way to build a cheap motor that puts out 300hp .... get a 360 magnum and put a carb with a carb intake on it ,,, under 600 u can have a mint motor ... if u want cheap motor for a mud truck
The Guru
Joined: Jan 2004
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From: Airdrie Canada
I ran a set of PDR 40/3B with no exhaust. That set-up spooled pretty fast without the exhaust. Once I added the exhaust, it slowed down some. I think I scared my neighbor hood with it though anything. I just finished putting on the twins and had no exhaust ready. You have to try stuff. I have even tried running my 300C srt without the exhaust on it. Now thats one noisy car.
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Joined: Feb 2002
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From: Red Deer, Alberta Canada
so how exactly are these being dyno proven? what kind of scientific method is being used> I understand fully the technical aspect of what you're saying, but i don't believe it. that pipe diameter increase of 1 or 2 inches produces a measureable loss of low end performance.
Mike, you are the turbine expert... Am I not interpreting the results correctly?
The Guru
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From: Airdrie Canada
I thought that it ran better with the open exhaust, of course I just put on twins on. I didn't not dyno the truck at that time. I'm with Luke, backpressure is not you're friend. Honestly it would be hard pressed to see any difference between 4in vs 5in. I just think that 5in stacks look cooler. Which pump you running Jamie and what year is the motor? You running a VE pump on that thing? We just gonna have to dyno tune that sweet ride up at our next dyno outting. I just want time off so I can have time to pull wrenchs, my hemi is starting to look good to me. I want to start driving the old ride again. I miss the shaking and the rattle beast.
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From: Red Deer, Alberta
I thought that it ran better with the open exhaust, of course I just put on twins on. I didn't not dyno the truck at that time. I'm with Luke, backpressure is not you're friend. Honestly it would be hard pressed to see any difference between 4in vs 5in. I just think that 5in stacks look cooler. Which pump you running Jamie and what year is the motor? You running a VE pump on that thing? We just gonna have to dyno tune that sweet ride up at our next dyno outting. I just want time off so I can have time to pull wrenchs, my hemi is starting to look good to me. I want to start driving the old ride again. I miss the shaking and the rattle beast.
The Guru
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From: Airdrie Canada
At least its new stuff. The first thing to try is a p pump. I have a liquid to air IC available, if you want. I trade it for your 2001 motor and 5spd tranny. Made you laugh, its your's if you want it. I bought one and got two, an ebay buy.
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From: Fort McMurray, Alberta
I have five inch exhaust on my 5.9 and i dont have an issue. my pretty plain truck turned almost 500hp on the dyno with no much put into her, and loosing power to the 37 inch rubber and 6 inch lift. so you may all have your theories, but my truck had it on when i bought it, it has unique sound that no one else has in town, and when i leave you all in my black smoke thats all that matters to me!! because in the end its gonna be a girl in a sweet cummins diesel thats going to kick all your butts anyways!!!! lol later!
Its not that you wont make power with a 5", its just that it isnt going to give you extra power over a 4". And in some instances it has been shown to actually hurt power,, not by bunches, but by some.
Kevin
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