[sherman8r]

I've been searching through old posts trying to find out if i need a regulator on my 408ci sbc. I have a 750 race style proform carb. and a carter M4891 strip super series mechanical fuel pump that is rated at 7 to 8.5 psi. Its a 3900# street car with a 500 lift cam and dart pro1 platinum heads. Thanks,Ken

 

[poncho62]

Generally, a mechanical pump will not produce enough pressure to overwhelm a needle and seat. Electric fuel pumps put out more pressure. I would say no......

 

[sherman8r]

thanks for the info :welcome:

 

[hotrod389]

Mechanical Fuel Pumps Will Float Over The Bowls On A Demon Jr.
Hook It Up, If The Carb Overflows, You Need A Regulator.

 

[techinspector1]

No modern 4-barrel carburetor needs over 5 psi pressure at the carb inlet. You could run a 1,000 hp motor with 5 psi fuel pressure, so long as you have the VOLUME there to feed the motor.

More pressure can overload the needle and seat and blow raw fuel into the intake manifold, presenting you with tuning nightmares. First, find out what the pressure is at the carb inlet. If it is excessive, get the pressure under control.