C3 sump install.
Thread Starter
Instructor
Joined: Jul 2015
Posts: 106
Likes: 23
From: Holland, Michigan
C3 sump install.
75’ is getting a drink change. Sent out the 400sb and it will be coming back as a 421 sb! Went through Eric at HPI and picked up one of his awesome 850cfm E85 built carbs.
along with that we decided do to the c3’s fuel tank design. It would be in our best interest to install a sump. Along with all of the other fuel system changes. Ensuring we have enough fuel under hard launching!
did some practice runs on the old tank the other night. Mocked up and welded in a plate the same size and thickness as our sump to ensure the welder is set to exactly where it needs to be, and also, everyone knows a plan in their head or even paper never goes to plan. So far with a little bit of fab work(I enjoy the most in any project). Tonight, I’ll finish forming the sump to the tank, and weld it in!
Race Director
Joined: Jul 2015
Posts: 13,082
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From: SW Florida.
By sump you mean baffles? And is that a new tank never had gas in it? I brazed a bike gas tank dent puller holes. Filled with water 5 times. Still blew flame 3 feet out the filler neck.
Race Director
Joined: Jan 2000
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From: Corsicana, Tx
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I put one on mine many years ago. Works great. Might add a drain plug...comes in handy at times.
JIM
JIM
Thread Starter
Instructor
Joined: Jul 2015
Posts: 106
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From: Holland, Michigan
already on it Jim, but great minds think alike. After some research and talking to some other gurus. We decided we would use one bung in the sump for obviously our supply line and the other to drain. Then on the side further up the tank weld our return line bung in to have the fuel come back into he main chamber of the tank. We came up with that due to return pressure isn’t very much but we didn’t want to create more turbulence inside the sump itself.
Thread Starter
Instructor
Joined: Jul 2015
Posts: 106
Likes: 23
From: Holland, Michigan
brand new tank fresh from the vendor, the holes are to act as a baffle to retain fuel in the sump that is being installed.
Team Owner
Joined: Jul 1999
Posts: 65,492
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From: Orange Park Florida
Late shark, I can't say, but my '72 got rid of the spare/carrier, and I added a 5 gallon steel air tank from HF as a gas tank, under and forward of the main tank, it is the sump and is gravity fed from main tank, pump is tied off to the rear frame, vents/returns/lines are totally stock, the 5 gallon tank acts to stop fuel slosh problems with cornering, and it making engine stumble on a lo tank level.....
so 23 gallon capacity total, now.....
never even dropped the tank for the install....
so 23 gallon capacity total, now.....
never even dropped the tank for the install....
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already on it Jim, but great minds think alike. After some research and talking to some other gurus. We decided we would use one bung in the sump for obviously our supply line and the other to drain. Then on the side further up the tank weld our return line bung in to have the fuel come back into he main chamber of the tank. We came up with that due to return pressure isn’t very much but we didn’t want to create more turbulence inside the sump itself.
JIM
Le Mans Master
Joined: Oct 2010
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From: melbourne florida
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Water in a gas tank is a dumb move. Run exhaust gas from a tailpiece through it until the gas fumes are burned out.your lucky it just shot flamestream out I saw a tank explode after a guy flushed it with water. You could also have a radiator shop boil it out.
that's a nice sump! I'm sure it will work well.
that's a nice sump! I'm sure it will work well.
Thread Starter
Instructor
Joined: Jul 2015
Posts: 106
Likes: 23
From: Holland, Michigan
Great looking work guys! All the tank dumps look great.
the only thing we failed to take into account is our sump is not deep enough for the lines to clear the rear tank support/brace. Somewhat left with the option of notching out the brace or spend some more time researching another option.
the only thing we failed to take into account is our sump is not deep enough for the lines to clear the rear tank support/brace. Somewhat left with the option of notching out the brace or spend some more time researching another option.