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Petrol tank outlet


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If you mean the petrol tank, mine is 1/2" UNF x 20TPI. Just brought a larger adaptor (brass with push on adaptor)to allow more fuel to flow and it screws directly in in place or the nut and copper pipe.

Colin.

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I bought one of those too but yet to  fit it, looks well made

Edited by Steves_TR6
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Surely the hole in the bottom of the tank needs enlarging to mate with a larger diameter pipe?  Screwing a 1/2” diameter adaptor into a 5/16” hole does not change the original supply hole that is drilled in the tank.  You need to drill out larger the hole in the tank outlet union that is brazed into the tank.

snake oil part?

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I understand that the part fits the original hole but has a larger bore, achieved with thinner walls ?

i’ll post pics when i get to it!

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58 minutes ago, Steves_TR6 said:

I understand that the part fits the original hole but has a larger bore, achieved with thinner walls ?

i’ll post pics when i get to it!

So the hole in the tank is not any larger to allow more fuel flow.

The outlet hole in the tank remains as the restrictor.

Peter W

PS. I have fallen in now.  Larger outlet means that a larger diameter rubber pipe can be fitted.   The larger tank outlet union external diameter is the same as the inlet to the Bosch or what have you pump.  Meaning bigger flexible pipe is used but no increase in fuel flow through the tank outlet restriction.  

Edited by BlueTR3A-5EKT
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36 minutes ago, BlueTR3A-5EKT said:

So the hole in the tank is not any larger to allow more fuel flow.

The outlet hole in the tank remains as the restrictor.

Peter W

PS. I have fallen in now.  Larger outlet means that a larger diameter rubber pipe can be fitted.   The larger tank outlet union external diameter is the same as the inlet to the Bosch or what have you pump.  Meaning bigger flexible pipe is used but no increase in fuel flow through the tank outlet restriction.  

On my tank the hole through the tank is 7.9mm, but the original pipe I/D when removed was 6.2mm.

 

IMG_0165.jpg.3bd3ce65c68b4bf4a40a12a04ec26ccd.jpg

The new adaptor I/D is 7.9mm all way through, so increases the diameter by 1.7mm. This gives an increase in I/D of +30%, but  an increase in area of +65%, so for a fixed head of petrol this must be a significant benefit without re-drilling and re-tapping the tank?

Colin.

 

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4 minutes ago, c.hydes said:

On my tank the hole through the tank is 7.9mm, but the original pipe I/D when removed was 6.2mm.

 

IMG_0165.jpg.3bd3ce65c68b4bf4a40a12a04ec26ccd.jpg

The new adaptor I/D is 7.9mm all way through, so increases the diameter by 1.7mm. This gives an increase in I/D of +30%, but  an increase in area of +65%, so for a fixed head of petrol this must be a significant benefit without re-drilling and re-tapping the tank?

Colin.

 

Thank you that is an excellent explanation and photo demonstration.   I understand now, the new union seats on a crush washer rather than inside the tank outlet with an olive, hence the increased area through the bore.

Peter W

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Thanks for the pics Colin, nicely explained.

now, how many extra BHP will i get ..... :-)

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