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Homemade Fuel Pin

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I'm working on a more aggressive fuel pin for my '92 Dodge Posted Image. I used a Grade 8, 3/4" diameter 4" long bolt for the basis of the pin. More to come!

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In this pic, the bolt has been machined down to .475. I'll use emery cloth coated with thread cutting oil to reduce the pin to .467-..468" diameter.

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This pic shows the 1st successful fuel pin I cut, on the left is the stock pin. The next one is gonna be cut a bit deeper Posted Image

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Here is the pin drilled and tapped for a 1/4x28 bolt. I have also polished the pin down to .468" using 220 grit emery cloth. I wish I had some 320 grit stuff, but this pin is already looking much better than my 1st pin Posted Image. Virtually no tooling marks on the pin. So far, so good(knock on wood).

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Here are a couple of pics of the profile cut into the new pin. The thinnest part of the pin measures .115". My current fuel pin's thinnest part measures .145". The factory stock fuel pin at its deepest setting is measured at .245". I used a milling machine to cut the profile, and in these pics, the pin is chucked into an old Reed-Prentiss lathe to be cut off.

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I used an adjustable turntable clamped to the bed of the milling machine. IMHO, that turntable is the most important tool that is used with the milling machine :).

That's very cool! I love my old South Bend Lathe... Wish I had a Mill.

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    Here is the finished pin. Ran the truck into town earlier today. The new pin sure made a difference! The truck now wants to pull the front end off the suspension at a bit over 1/2 throttle. It was definitely a worthy project!

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    You know guys, I would be willing to sell these pins for pretty cheap, say $50 plus 5 or 6 bucks shipping. PM me if interested Posted Image

    just have to throw in my .02 cents here, because i tried the same thing in my machine shop at school.the grade 8 may seem hard bet could possibly still be to soft for a fuel pin. the stock pin i beleive was 40 rockwell which is HARD. i used tool steel and heat hardened it twice. and mine still ended up grooving. if it starts to groove badly it could affect how the afc work. just something to think about when you run it

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    I have not heat-treated my pin at all, and only mild grooving on my pin......I think the grooving has more to do with the squared off end of the horizontal fuel rack pin that causes the groove. If I can can find a spare fuel rack pin to measure, I might be able to solve these grooving issues. My best friend has a 91.5 CTD with a stock fuel pin. I inspected his stock fuel pin on Dyno Day Mar. 17, and his pin was severely grooved. I'm sure the squared off end of the fuel rack pin cut the groove in his fuel pin.

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