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Discussion Starter #1 (Edited)
Hi,

I have a 1975 RHD GTj and I intend to drop a twinspark into it. I am picking an engine up this week and from reading all of the posts on here it looks relatively straightforward to convert it. I will be keeping the original fuel injection from the 75, but I'm not sure how to plumb in a fuel return line to my existing tank.

Has anyone got any pointers?

Cheers
Tim
 

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Is the tank rated for Fuel Injection? You may find at 35+ psi it's not quite air(or gas)tight. Otherwise, I would get an AN fitting with a 90 degree bend and drill a hole in the top of the tank close to the fuel level sender and stick your hand in and screw in the fitting. Make sure to get a plastic crush washer as well.
 

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Regarding the fuel line, I bought new line from Napa and a tubing bender. The first time I did it, I used the regular steel tubing. While it worked, it looked awful. Unhappy with my first set, I bought some rigid fuel line there that was sort of a dark olive drab green. It was a little more expensive, but much easier to bend. I highly recommend it.

Good luck with it.

Regards,
Lawrence
 

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Discussion Starter #4
Thanks for the pointers.
I guess the tank will be ok, it was replaced about 10 years ago and the car has only done 1,000 miles since.

I'll be back with more questions, once I get started!

Tim
 

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I used a VW Mk1 GTI in tank pump & level sender which has the return line in the top.
If you contact automec.co.uk & buy one full length of fuel injection copper supply line it is just enough to reach to & from the std fuel injection.
My 76 GTJ twin spark built by myself with std fuel injection works perfectly.
Im in Kent UK & can help you with any questions you may have.
Cheers Keith
 

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Discussion Starter #6 (Edited)
Hi Keith,

I was hoping you would post, I'm looking to build a white version of your car! I'm in Sussex, you can't live that far away.

Does the VW sender unit fit the Alfa tank? That sounds too easy! I've got the 75 pump from under the car and was going to use that, do you only have the in tank pump?

cheers
Tim
 

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Why not fit a proper surge tank and use the original pump as a lift pump to that, then run an EFI pump to your engine, with a return line to the top of the surge tank. Before anyone says about fuel heating issues, it has been proven conclusively, beyond doubt, that unless your line runs next to a heat source, recirculation will not heat the fuel. The tests were done on a 1200hp twin turbo V8....enough chance to generate heat, there!!!
 

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Discussion Starter #8
Why not fit a proper surge tank and use the original pump as a lift pump to that, then run an EFI pump to your engine, with a return line to the top of the surge tank. Before anyone says about fuel heating issues, it has been proven conclusively, beyond doubt, that unless your line runs next to a heat source, recirculation will not heat the fuel. The tests were done on a 1200hp twin turbo V8....enough chance to generate heat, there!!!
Hi Oz,
I have looked at surge tanks, but they all seem to have a fuel return line which looks like it needs to go to the tank? Also, my original pump is mechanical, attached to my 1.6 engine which is coming out - so i still need to fit an electric pump somewhere.
I'm open to any suggestions to make life easier!

Tim
 

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Hi Tim
The VW unit has a bayonet mount & the 105 has 6 4mm screws. Lay the rubber joint ring over the vw unit, mark out & drill clearance holes. Its very nearly a perfect fit. Im still dabbling to get the gauge calibration correct & I did extend the pickup tube to reach the base of the tank. One observation is the pump is noisy when not submerged later stuff is in a polystyrene tube to muffle the pump noise. I have pmd my address to you.
 
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