Stumbled across a possible 2"primary LSJ Header?..
11-20-2009, 08:47 AM
#27
11-20-2009, 10:10 AM
#28
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honestly it's not worth it think about this:
4 x 1.5" = 6" area for exhaust to travel through
4 x 1.75 = 7" area
4 x 2" = 8" area
all three of which, go right into at the biggest a 1 x 3" pipe. this is why i find it funny when people argue about how much better a 1.75" primary header is than a 1.5" primary header
the more volume you have, the slower the velocity. the slower the velocity, the less scavenging effect you have. so bigger on everything, isn't always better.
4 x 1.5" = 6" area for exhaust to travel through
4 x 1.75 = 7" area
4 x 2" = 8" area
all three of which, go right into at the biggest a 1 x 3" pipe. this is why i find it funny when people argue about how much better a 1.75" primary header is than a 1.5" primary header
the more volume you have, the slower the velocity. the slower the velocity, the less scavenging effect you have. so bigger on everything, isn't always better.QTY 4 x 1.5"= 7.07in^2
QTY 4 x 1.75"= 9.62in^2
QTY 4 x 2.00"= 12.57in^2
QTY 1 x 3.00"= 7.07in^2
Wow, triple post, my bad...
11-20-2009, 10:47 AM
#29
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11-20-2009, 12:51 PM
#30
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who gives a crap about my math, the point of the thing is that 4 x 2" primaries is bigger than a damn 3" single pipe.
we can argue about african swallows being faster than european swallows in our next round if you would like, and you can calculate the which bird uses the best navigational method to travel from fixed points
and if you dumbies want to get really technical, all of your math can be wrong as well because we didn't specify the gauge of the tubing being used.
we can argue about african swallows being faster than european swallows in our next round if you would like, and you can calculate the which bird uses the best navigational method to travel from fixed points
and if you dumbies want to get really technical, all of your math can be wrong as well because we didn't specify the gauge of the tubing being used.
11-20-2009, 02:11 PM
#31
who gives a crap about my math, the point of the thing is that 4 x 2" primaries is bigger than a damn 3" single pipe.
we can argue about african swallows being faster than european swallows in our next round if you would like, and you can calculate the which bird uses the best navigational method to travel from fixed points
and if you dumbies want to get really technical, all of your math can be wrong as well because we didn't specify the gauge of the tubing being used.
we can argue about african swallows being faster than european swallows in our next round if you would like, and you can calculate the which bird uses the best navigational method to travel from fixed points
and if you dumbies want to get really technical, all of your math can be wrong as well because we didn't specify the gauge of the tubing being used.
11-20-2009, 02:22 PM
#32
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If you want to argue the part about the backpressure vs. vvt, vvt changes the pressure wave about the same as more or less backpressure and/or scavenging would. i'm no engineer nor have i ever claimed to be so it may be hard for me to explain stuff technically in my posts. but what i do is build fast cars. some of which you could unplug 7 of the 8 cylinders and it would still put down more power than most of the cars on this site.
again the whole thing was initially about scavenging and velocity, not about backpressure so the argument can go away now
11-20-2009, 02:24 PM
#33
you're right nothing i posted makes any sense. the documents clearly state that more backpressure helps out on the low end EXCEPT in properly tuned cars, which means pretty much a custom tune and not one on the car off the factory line, and even then you have to get a good tuner that understands peak and WOT runs are 5% of what a car does. It takes a hell of alot of skill of which i would say less than a dozen people on this site have (myself not in the group) to be able to properly tune a partial throttle operation with the most efficiency.
If you want to argue the part about the backpressure vs. vvt, vvt changes the pressure wave about the same as more or less backpressure and/or scavenging would. i'm no engineer nor have i ever claimed to be so it may be hard for me to explain stuff technically in my posts. but what i do is build fast cars. some of which you could unplug 7 of the 8 cylinders and it would still put down more power than most of the cars on this site.
again the whole thing was initially about scavenging and velocity, not about backpressure so the argument can go away now
If you want to argue the part about the backpressure vs. vvt, vvt changes the pressure wave about the same as more or less backpressure and/or scavenging would. i'm no engineer nor have i ever claimed to be so it may be hard for me to explain stuff technically in my posts. but what i do is build fast cars. some of which you could unplug 7 of the 8 cylinders and it would still put down more power than most of the cars on this site.
again the whole thing was initially about scavenging and velocity, not about backpressure so the argument can go away now
11-20-2009, 05:12 PM
#36
11-20-2009, 06:28 PM
#38
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Exhaust gases coming out of a motor are very hot, 1000+ deg F. Well that exhaust gas is hot, it has a lot of velocity. As it cools, its velocity slows down, thus you need to start reducing the size of the exhaust piping to keep the velocity up. So a bigger primary is indeed better for flowing those hot exhaust gases, but there is only a very small handful of people on this site who are supercharged that could even take in any advantage from that versus the amount of money it would cost to make.
11-20-2009, 06:30 PM
#39
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bball anyone?
11-20-2009, 08:35 PM
#45
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Hey! Thats RD Fabs! They do amazing work with stainless parts. They are the first people to make a full 3" intake for the lsj that doesnt bulge the fenderwell AND they are also the first to make an exhaust manifold with 2" primaries for the cobalt. I know the guys personally and a good friend of mine has had ALOT of work done with them.
Best. Quote. Ever.
Best. Quote. Ever.
Last edited by JohnnySasakiMGS; 11-20-2009 at 08:36 PM. Reason: Automerged Doublepost
