1HD-FTE Into 80 Series - 6mm or 8mm Return Fuel Line?? (1 Viewer)

[gnarlynick2072]

Hello everyone,

I am well into my conversion project I realized that the native fuel return line is 6mm on the 80 series, but the 1HD-FTE uses 8mm.

For those of you that have done 1HD-FTE conversions on your 80 series - did everyone size up to 8mm on their return lines? This is quite the huge retrofit as it would require the return lines to be upsized on the main tank and, in my case, the sub tank as well which would be a custom fab job.

What's the consensus on this?

 

[mudgudgeon]

I reckon ideally 8mm.

Toyota upsized supply fuel line on early 1hd-t due to fueling issues. I'd avoid anything that might restrict flow in the system.

Not sure it's actually critical as the return is under pressure.

You could change lines to 8mm, and leave tank fittings at 6mm. Most flow restriction will be in the line. Not ideal, but maybe a middle road.

Can you use the existing supply line as your new return? And upgrade the supply to 12mm as used by Toyota?
You don't say what vehicle you're doing the conversion in. Fzj80?

 

[TheBussman]

if your going from gas to diesel you can use your old 8mm supply line as a return and then run a new 12mm line for supply.

 

[Jorgito]

I used 12mm feed from 1h-ft and 1fz-fe feed as return. Seems ok.