Weber 48 IDA Fuel Inlet Mod
09-16-20, 12:27 PM
#1
djessence
Thread Starter
Weber 48 IDA Fuel Inlet Mod
Couple questions that I have only seen mentioned but not really explained.
Weber 48 IDA on a 13B 6 port, race application. Done all the various changes as a starting point so good there. There is a thread where Wacky (new user name though?) mentioned to "remove the fuel filter (done) and drill down the fuel funnel inlet thing" or you'll run into fuel starvation issues.
Has everyone done this? I'm hesitant to start drilling/cutting a new carb but if its something everyone has done then I guess I'll do it. I assume it is drilling it down so fuel does not have to come in, up and then fall into the bowl? The idea I am guessing is don't give the fuel a tortuous path to get into the bowls and just keep the flow straightforward?
Then my dumb question: you keep the air horns on underneath the K&N filter right? Just seems like a super tortuous path for air to get in there but from a velocity perspective makes a lot of sense.
Weber 48 IDA on a 13B 6 port, race application. Done all the various changes as a starting point so good there. There is a thread where Wacky (new user name though?) mentioned to "remove the fuel filter (done) and drill down the fuel funnel inlet thing" or you'll run into fuel starvation issues.
Has everyone done this? I'm hesitant to start drilling/cutting a new carb but if its something everyone has done then I guess I'll do it. I assume it is drilling it down so fuel does not have to come in, up and then fall into the bowl? The idea I am guessing is don't give the fuel a tortuous path to get into the bowls and just keep the flow straightforward?
Then my dumb question: you keep the air horns on underneath the K&N filter right? Just seems like a super tortuous path for air to get in there but from a velocity perspective makes a lot of sense.
09-16-20, 12:59 PM
#2
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keep the air horns, you can change the length, but i think it needs them for the carb to work. i'm not sure exactly, but as long as there is about an inch between the stack and the filter it should be fine.
the inlet mod is really easy, once you take the carb top off you'll see the passage drilled in the casting, and you just drill it bigger. its probably not a bad idea to chamfer the hole too. if you're making a ton or power or have really bad BSFC you probably should do this, but if you're not trying to run stupid rich and not making a ton of power its probably not needed.
the inlet mod is really easy, once you take the carb top off you'll see the passage drilled in the casting, and you just drill it bigger. its probably not a bad idea to chamfer the hole too. if you're making a ton or power or have really bad BSFC you probably should do this, but if you're not trying to run stupid rich and not making a ton of power its probably not needed.
09-16-20, 01:30 PM
#3
djessence
Thread Starter
keep the air horns, you can change the length, but i think it needs them for the carb to work. i'm not sure exactly, but as long as there is about an inch between the stack and the filter it should be fine.
the inlet mod is really easy, once you take the carb top off you'll see the passage drilled in the casting, and you just drill it bigger. its probably not a bad idea to chamfer the hole too. if you're making a ton or power or have really bad BSFC you probably should do this, but if you're not trying to run stupid rich and not making a ton of power its probably not needed.
the inlet mod is really easy, once you take the carb top off you'll see the passage drilled in the casting, and you just drill it bigger. its probably not a bad idea to chamfer the hole too. if you're making a ton or power or have really bad BSFC you probably should do this, but if you're not trying to run stupid rich and not making a ton of power its probably not needed.
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