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1970 Cougar, mechanical pump. i am wondering if it is overpowering the seats in the Edelbrock. Edelbrock recommends only about 6 psi. car always smells rich and i can't lean it out. no leaks detected. it does need a valve job though.

how do i test the output pressure? and if it is too high, what is involved with installing a regulator? thanks-
 

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Buy you a fuel pump/vacuum tester from auto parts store, fairly cheep, disconnect fuel line from carb, insert tester start engine, watch gauge. I doubt you have much over 4 lbs. but if you need to install a regulator, anywhere between the fuel pump and carb. will work.
 

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3-4 lbs is plenty for a carb 6 is probably to much....I doubt your mechanical makes more than 5 anyway....so you don't need a regulator I'm sure. You can get a cheapy inline fuel guage from Jegs/Summit and you can see what it is instantly anytime. More than likely you need to adjust the carb or get the correct jetting for your application.....rarely does "out of the box" run right without tweaking.
 

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I could be in the dark here fellas but my 289 Edelbrock mechanical fuel pump produced 7lbs of pressure which overloaded my Edelbrock 600cfm 4barrel carb. I guess the factory pump might not produce as much, but I'd be curious to see the specs of such. The engine never ran right until i installed a regulator.
 

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My stock fuel pump makes 6 psi and my Autolite and Holley's run fine with it. All the best with the test.
 

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I've bought a Holley pump that was defective, produced way too much pressure.
Check at idle then check during a hard top gear pull. Should be no less than 4 psi and no more than 6. Consult the carb manual for pressure requirements.
 

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Is it a 'new' rebuilt pump? Many of those are putting out 7 - 8 psi. I've had the same problem when i replaced pumps on my cars when they went bad. Make sure the float is adjusted properly and if in doubt, install a new needle and seat assembly.
 
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