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Posted

I need some guidance. I have a 72 K-20 with a 350 small block, 1406 Edelbrock carburetor and the stock mechanical fuel pump. The engine is running a little rough at idle and the exhaust smells rich. I tested the fuel pressure and it bounces from 8-9 psi (seems high for a mechanical fuel pump).

 

I searched around for guidance on a deadhead fuel pressure regulator and there seems to be conflicting information. Some say a deadhead pressure regulator will damage the mechanical fuel pump.

What’s the best option for a regulator or should I go in a different direction?

Posted

regulator- https://www.summitracing.com/parts/mrg-2015

Forum for efi pump conversion- http://www.gearhead-efi.com/gm-ecm-pcm-conversion/in-tank-fuel-pump-conversion.html

 

I don't know the answer to your mechanical fuel pump question, but I do have this alternative, which is a lot of work, but if you're willing to do it, its very reliable. and of course you could do a much prettier job of it than I've done.

 

I have a 400 SBC, Holley 650 carb, that's been running off an 89-95 gm TBI 350 fuel pump and tank for the better part of four and a half years now, the pump puts out 14 psi +/- and its been turned down with this regulator to 7 psi. truck starts and runs great every time I turn the key. it has the factory TBI fuel lines, both feed and return, all the way to the back of the engine, I cut the two threaded nut fittings off of the lines, leaving the large "flare" so I could squeeze rubber line over those hoses. its a tight fit but they will go, and they'll never come off either. then I wired up the fuel pump to a relay powered by an ignition source and the sending unit to my fuel gauge. I have the factory TBI steel fuel filter on the frame still plus a small clear plastic one near the carb. probably over kill but it doesn't hurt.. just check the final pressure on the output of the regulator to make sure its working, I used a cheap fuel pressure gauge on the end of the hose for that. in my application I have swapped a 72 body onto a 1994 frame, so the TBI fuel tank bolted right up, in your case, you'll have to follow that link to the efi pump conversion thread, there's plenty of ways to go about that. its basically what a lot of the LS swap guys do to their c10 fuel tanks essentially. connecting a high pressure in tank pump to the pickup tube inside of the tank. more than one way to skin a cat, but you could have all these parts from a salvage yard for pretty cheap. hope this helps. sorry I couldn't answer you're question. these are the best pics I have of my setup. and yes it is pretty nerve racking having the regulator right above the distributor. meant to move it about three years ago but never got around to it haha. 

 

 

 

 

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