Fuel System - gas and alcohol
#11
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Wait a minute, Bigger engine pulling more air with more velocity but less fuel, that does not make any sense to me and I have been running alcohol for 15 years.
Tom, Do you run a smaller jet than the guys with smaller engines?
Tom, Do you run a smaller jet than the guys with smaller engines?
#13
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Originally Posted by davis419b
Wait a minute, Bigger engine pulling more air with more velocity but less fuel
BTW, I'm running a BG400 pump.
George
#14
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I would be more inclined to believe that with an electic fuel pump you need a bigger jet for more volume due to the lack of volume the pump delievers. Have you ever ran a mechanical pump with your set-up. Years ago i bought an alcohol carb from Barely Grant. I had a Barry Grant pump and they told me it wouldnt work and they were right. Have had a mechanical pump every since. I do not believe you need that bid of jet with an Enderle pump.
Zipper, where are you i need you to jump in here !!
Zipper, where are you i need you to jump in here !!
#15
I can tell you that what George is saying is the exact thing I am going through right now. We have an older Rupert 950 that we had on a 468. It had 165 jets in it, I put it on my 383 that is a lot milder motor that the 468 and have had to go up to 173 jets, went quicker and faster than with the 165s, and I am going to go up even more the next time out. I am using an electric pump also. The one thing that I will have to watch with an electric pump is emptying the bowls faster that the needles will let fuel in with the bigger jets because I can't raise pressure with rpm like a mechanical pump, even though that is probably the better way to go.
Curtis
Curtis
#16
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I rest my case! Find me someone who is running that big of jet with a belt drive pump, you wont. The guy in question here is running a belt drive pump. If you run the right fuel system you wont need all that fuel pressure bleed off crap, just set the fuel pressure and go!!
#17
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Originally Posted by davis419b
I would be more inclined to believe that with an electic fuel pump you need a bigger jet for more volume due to the lack of volume the pump delievers. Have you ever ran a mechanical pump with your set-up. Years ago i bought an alcohol carb from Barely Grant. I had a Barry Grant pump and they told me it wouldnt work and they were right. Have had a mechanical pump every since. I do not believe you need that bid of jet with an Enderle pump.
Zipper, where are you i need you to jump in here !!
Zipper, where are you i need you to jump in here !!
just my .02
Zip.
#18
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Originally Posted by davis419b
I would be more inclined to believe that with an electic fuel pump you need a bigger jet for more volume due to the lack of volume the pump delievers.
Curtis, you are going in the right direction.
George
#20
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The guy in my post above that had 209 jets installed is using a belt driven pump. I didn't invent physics I just have to apply them like everyone else. I don't intend on getting into a pizzing contest on which pump is better. Different type pumps require different setups. Like I said in my original post, it works for me. If it doesn't work for you that's fine, too. And I'll let it rest with that.
George
George