Weber draw through fuel system help
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Re: Weber draw through fuel system help
I know this one, fit a boost sensitive fuel pressure regulator
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Re: Weber draw through fuel system help
These single side drafts have a very small float bowl, and a somewhat small needle inlet and seat. For 8 to 10 pounds boost, you may get away with an unregulated pump at 2 psi fuel pressure. Personally, I wouldn't take the chance. For any more boost than 10 pounds, you should absolutely have a regulator that is referenced to boost pressure, so you can keep up with the volume of fuel that the engine will need. Run a 60 psi EFI pump with a return line going back to the tank, and a Malpassi or similar boost referenced regulator. Set it down to 2 or 3 psi, and you'll never have to worry about running lean, ever. That is the way it has been done for decades. Read Turbomania from the 90's. Mr. Craineum's reference to thermodynamics is mis-used in this circumstance.
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Re: Weber draw through fuel system help
Buggsy is spot on I at first was running only 10psi boost with a non boost sensitive fuel pressure regulator witch was set to 3psi and even at 3psi I was over powering the floats on my Weber DCOE carb and if I stayed at 10psi for more than a few seconds I was getting lean popping and bang (not good) so I followed the advice on this thread and fitted a boost sensitive fuel pressure regulator wind my idle pressure down to 2.5psi (witch for some reason is the lowest it will go) and now I can happy sit at 13 psi boost with out going lean
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- Chip Birks
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Re: Weber draw through fuel system help
Are you running a sidedraft weber or dellorto?richardcraineum wrote: βSun Nov 19, 2017 5:25 pm u don't need to raise fuel pressure on a draw through, been running one for about 3 yrs now about 13 lbs of boost with 3lbs fuel pressure. I'm no scientist but remember the law of fluid dynamics, pressure goes up and volume goes down. the only reason to increase fuel pressure in a blowthrough is so that the boost doesn't go higher than fuel pressure and push fuel backwards out of the fuel bowl , not an issue on draw through
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Re: Weber draw through fuel system help
Me ?
Iβm running a Weber DCOE side draft
Iβm running a Weber DCOE side draft
- Chip Birks
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Re: Weber draw through fuel system help
Hey richard cranium, can you please answer the question I asked?
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Re: Weber draw through fuel system help
He is running a modified DCOE that is now a split shaft vacuum progressive carb. It's on the theSamba.Chip Birks wrote: βFri Nov 24, 2017 12:27 pmAre you running a sidedraft weber or dellorto?richardcraineum wrote: βSun Nov 19, 2017 5:25 pm u don't need to raise fuel pressure on a draw through, been running one for about 3 yrs now about 13 lbs of boost with 3lbs fuel pressure. I'm no scientist but remember the law of fluid dynamics, pressure goes up and volume goes down. the only reason to increase fuel pressure in a blowthrough is so that the boost doesn't go higher than fuel pressure and push fuel backwards out of the fuel bowl , not an issue on draw through
Stripped66 wrote:The point wasn't to argue air temps with the current world record holder, but to dispel the claim that the K03 is wrapped up at 150 HP. It's not.
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Re: Weber draw through fuel system help
Samba link anyone ? (saves me searching)
'65 Bus with a JDM Subaru EJ20 Turbo
Built by Germans powered by Japanese and brought together by Canadians
Built by Germans powered by Japanese and brought together by Canadians
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Re: Weber draw through fuel system help
Damn iPhone won't let me copy a link.
Performance forum on page 3. Progressive Weber thread...
Performance forum on page 3. Progressive Weber thread...
Stripped66 wrote:The point wasn't to argue air temps with the current world record holder, but to dispel the claim that the K03 is wrapped up at 150 HP. It's not.
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Re: Weber draw through fuel system help
So you're saying this will support 20+ psi in 4th gear in a 2 liter motor?
If so you have probably just done something that noone has ever done with a sidedraft at 3psi of fuel pressure.
If so you have probably just done something that noone has ever done with a sidedraft at 3psi of fuel pressure.
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Re: Weber draw through fuel system help
Keep us posted when you put a performance motor in it. I'd like to seethe pics of how your testing goes. And if its a 94 bore I know where you can get heaps of cylinders for cheap. You're gonna need them.
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Re: Weber draw through fuel system help
been there too
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Re: Weber draw through fuel system help
It's all about the carburetor being used, weber sidedraft has a small float bowl. You need to boost reference the fuel pressure regulator to keep fuel bowl supply happy when on sustained turbo boost.richardcraineum wrote: βFri Dec 01, 2017 3:53 pm if u mean me, it's actually on a 1600 (for now) and I did not exceed 20lbs. but yes 3lbs of fuel pressure. I don't get why this seems odd. say if we were talking small block Chevy or Ford and u build a 13:1 compression motor, u don't need to increase fuel pressure for this motor which has a higher compression than say a stock motor, compression doesn't affect the carb. draw through is same concept