Oooops!!!!!! I f***ed up.

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#1
Ok so I jb welder the diy carb intake manifold. But it accidentally shifted overnight. Now the 5/8 pipe isn’t aligned with the 5/8 hole. Is this a huge issue. Help. I belive with the benoulli affect, this decrease the pressure and increases the velocity due to this obstruction. If this is a problem, i really dont want to make the carb intake again, so create a better carb filter thing, like a snorkel.
 

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CrazyDan

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#2
That obstruction will lower the amount of air that can potentially enter your engine. You should remake it. maybe you can chisel or grind off the jb weld and try again? You are very successful at trolling yourself :ROFLMAO:.
 
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#3
That obstruction will lower the amount of air that can potentially enter your engine. You should remake it. maybe you can chisel or grind off the jb weld and try again? You are very successful at trolling yourself :ROFLMAO:.
How bad would the performance drop be? I don’t feel like grinding it off. Maybe if I make the carb less restrictive it will work. Plus, the total volume of air can will be the same due to conservation laws. It’s just the velocity will be higher and the pressure will be lower.
 

Street Ryderz

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#4
benoulli affect ? what does this have to do with anything,This is not fluid dynamics this is about air/fuel flow and atomization.The volume will be less due to lack of area and the velocity slightly higher at the same pressure,You didn't change the pumping efficaintcy,intake is a vacuum pulse aided by atmospheric pressure that does not change.
 
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benoulli affect ? what does this have to do with anything,This is not fluid dynamics this is about air/fuel flow and atomization.The volume will be less due to lack of area and the velocity slightly higher at the same pressure,You didn't change the pumping efficaintcy,intake is a vacuum pulse aided by atmospheric pressure that does not change.
So basically I am lowering the efficiency of the engine. If I created a snorkel to funnel more air volume at the carb filter part, would that counteract this.
 

Street Ryderz

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#6
So basically I am lowering the efficiency of the engine. If I created a snorkel to funnel more air volume at the carb filter part, would that counteract this.
No because the bottle neck is the intake,witch slows the charge from entering as quickly compared to one that free flows and is matched to the window and track.Area is important and when it changes in dia(smaller) it becomes a restriction.Stock intake dia is around 17mm i.d. and the window is 16.5mm on average and use's a 14mm carb,see where this is going? Most of us end up opening the window to atleast 19mm and some even more,so idealy you want the same thing the smallest dia really should be the carb so that each charge is metered by the carb body volume then it should be free flowing straight to the window for max volume to enter in that short pulse.
 
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#7
No because the bottle neck is the intake,witch slows the charge from entering as quickly compared to one that free flows and is matched to the window and track.Area is important and when it changes in dia(smaller) it becomes a restriction.Stock intake dia is around 17mm i.d. and the window is 16.5mm on average and use's a 14mm carb,see where this is going? Most of us end up opening the window to atleast 19mm and some even more,so idealy you want the same thing the smallest dia really should be the carb so that each charge is metered by the carb body volume then it should be free flowing straight to the window for max volume to enter in that short pulse.
ok so i knocked off the intake with a sledgehammer ground down the jb weld and re-jbwelded it. I put the thing on a elevated sheet of plexi glass so i could watch it and make sure it was perfectly lined up when it dries. Layed some 1" steel plate (that i stole from a scrap pile by the railroad) around it so it stays that way and doesn't shift around like before. heres a cool resource i found about the carb intakes. http://home.windstream.net/bsprowl/CarbMythFact.html
 

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