My manifold so far
#1
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here is my manifold design so far. wanted to go with somthing a little better than the tipical log style. hope it works out
![](http://i96.photobucket.com/albums/l191/o0Quicksilver0o/DSCF0369.jpg)
![](http://i96.photobucket.com/albums/l191/o0Quicksilver0o/DSCF0375.jpg)
the turbine inlet flange will be between cylinders 1 and 2
![](http://i96.photobucket.com/albums/l191/o0Quicksilver0o/DSCF0369.jpg)
![](http://i96.photobucket.com/albums/l191/o0Quicksilver0o/DSCF0375.jpg)
the turbine inlet flange will be between cylinders 1 and 2
#10
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id love some tips loki, i will not grind the next ones down. My main issues was splatter, i need to buy some weld kleen, I am also using flux core only. Im gonna get some argon/co2 some time and do dual shield. The heat seemed fine, was burning through on some of the thinner parts.. my feed may have been a bit high.
200gs, im going all mild steel, the engine flange is a doner from a stock 1.6 manifold, the pipe is sch 40 black pipe, the elbows shown are stainless, but im going to buy some mild steel ones to use insted, i just happen to have those laying around.
200gs, im going all mild steel, the engine flange is a doner from a stock 1.6 manifold, the pipe is sch 40 black pipe, the elbows shown are stainless, but im going to buy some mild steel ones to use insted, i just happen to have those laying around.
#13
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thread hijacking at its worse:gay:! never grind welds on manifolds only bad things can happen when you do that. that is the kind of design that i am trying to avoid. here it is half welded, cant weld the rest until i find the location for the inlet flange and cut the hole. should be done in a few days ill update then...
![](http://i96.photobucket.com/albums/l191/o0Quicksilver0o/DSCF0378.jpg)
#14
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nice welds, looks good!
do you think runner #2 should have face inwards towards runner #3 and #4 the flow can all meet into the center of the chamber and exit in the middle? As it is, it seems #2 and #1 will be disprutive of each other, plus #2 will flow weird turn.
All you have to do is flip it around correct?
do you think runner #2 should have face inwards towards runner #3 and #4 the flow can all meet into the center of the chamber and exit in the middle? As it is, it seems #2 and #1 will be disprutive of each other, plus #2 will flow weird turn.
All you have to do is flip it around correct?
#15
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Arent the orifices on the backsides of those runners a little small? Youre going to end up with a ton of turbulence in the 4-3 and 3-2 section because the exhaust gas is going to squeeze down to fit through that small cutout and then expand again in the next section.
Youre going to end up with a restriction outside each cylinder instead of a single restriction at the turbine wheel- so your manifold will end up absorbing a lot of the "work" that should otherwise be driving the turbine- work that will be expressed as heat. And since it wont be even across all the entire head (1-2 cylinders will flow a ton better than the 3-4 IMO) you may end up with different EGT and knock characteristics between the front and back of the head.
The whole point of the non-log manifolds is that the exhaust pulses take an equal amount of time to directly reach the turbine instead of the cylinders dumping their pressure into a communal pool which empties into the turbine- your design doesnt bring the benefits of the equal length design and introduces complications that the internally smooth log design lacks.
Youre going to end up with a restriction outside each cylinder instead of a single restriction at the turbine wheel- so your manifold will end up absorbing a lot of the "work" that should otherwise be driving the turbine- work that will be expressed as heat. And since it wont be even across all the entire head (1-2 cylinders will flow a ton better than the 3-4 IMO) you may end up with different EGT and knock characteristics between the front and back of the head.
The whole point of the non-log manifolds is that the exhaust pulses take an equal amount of time to directly reach the turbine instead of the cylinders dumping their pressure into a communal pool which empties into the turbine- your design doesnt bring the benefits of the equal length design and introduces complications that the internally smooth log design lacks.
#20
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I read somewhere (I think it was autospeed) that the log style design with the center runners coming straight out, actually lessened the impact of the outside cylinders "aimed" at eachother. Making it sound as though log manifolds aren't built like that just because they're easy to build that way.