Top End Miss

madmax/6 said
I ran that red pump tru a regulator on a 625 Holley vacume secondaries carb at 5.5 lbs..NO issues with my close to 1,000 lbs lighter car.My carb was a 600 but has been worked.He is heavier and running more carb on lesser engine,with more gear.I hate to admit it,,butt he might need more pump.Black pump with a REGULATOR set a 6 lbs running will just tell me I was at the brink with that red pump,and not enough for his car.VERY CURIOUS.Btw my car ran the same with my new black pump at 6 psi as it did with with the red at 5.5. Mark
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Whether the engine can use it or not, it may be that HIS red pump just can't fight the inertia in HIS car. Either way, I dont think 5.5 is enough at the gage, and if the gage is at 5.5, the carb needles wil be slightly lower.