HI fellow hambers, I have a 327 chevy sb with solid lifters and mild cam the question is what fuel pressure should I run with the rodchester two barrel tri-power set up . and do I need to run high volume fuel pump and electric pump at the same time or can I use the stock mechanical pump by its self? tell me your thoughts humbly john!
For years, GM cars stock from the factory ran fine with the stock fuel pumps. 348"'s with tri-power, 409's with dual quads. Pontiac Bonneville's with tri-power, GTO's. had tri-power setups..That might give you a clue. I also ran the stock GM pump back in the 60's with 3 dueces, 2 four barrels and tunnel ram systems. Never ran out of fuel, or had excessive pressure. Corvettes also ran fine with dual quad set-ups and stock pumps.
The Rochester two barrels don't like a lot of pressure, anything from 3 to 5 psi will work, some get away with more, some need less. The type of needle and seat you install will determine maximum fuel pressure. A stock, factory correct, standard fuel pump is all thats needed. If the car will set for weeks at a time, a small electric pump would be handy to prime the carbs with. Most of the small pulse pumps can be put inline, the factory pump will pull fuel through it while turned off. No need for both to work at the same time.
One more thing.... Use an adjustable fuel pressure regulator with a gauge and set it too????.... 4.5-5.0 psi...
Used an aftermarket pump with mine (holly, Ebrock) I got in a deal. Worked fine but did give some high pressure, went to a regulator (dial type) but found that the regulator was wrong on its readings, ex: 4=5.3, etc. Used a master pressure gauge to set pressure at 2.5 to 3 psi and all was great. Large base rochesters didn't like the high pressure.
thank you regulator was bad, back on the road and the radiator blew OH! well! it was a walker that lasted 40 years happiness is working on your hotrod
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