Holley 180 no more power after 4600rpm

[BobBrumby]

Yeh I have had my holley for a while and low to mid range is heaps better than the ****achi but after about 4600rmp does not pull at all and seems to go a little slower. I remember GD sayin his ea81 made good tourque out to 5500rpm. Could my fuel pump thats original i think not be putting out enough pressure? What is the stock pressure meant to taking in mind no fuel return on holley's. Or maybe bump the timing forwar a bit?

[NorthWet]

Yeh I have had my holley for a while and low to mid range is heaps better than the ****achi but after about 4600rmp does not pull at all and seems to go a little slower. I remember GD sayin his ea81 made good tourque out to 5500rpm. Could my fuel pump thats original i think not be putting out enough pressure? What is the stock pressure meant to taking in mind no fuel return on holley's. Or maybe bump the timing forwar a bit?

I assume that this is the "normal" 2-barrel progressive-opening Weber? Have you checked to make sure that you are getting full throttle opening?

 

I wouldn't think pressure would be so much of an issue as flow, since if the carb is not getting enough fuel the float needle would be unseated and almost any pressure would be enough. Have you done a hard run in the above 4600 rpm range, cut your ignition and rea the spark plugs? Lean or rich?

 

Have you checked to see if mechanical/centrifugal advance is functioning properly and reaching full advance?

 

Good luck!