Since the tracks are closed and the weather is summer like still here,I started looking for a/the reason my 440 does`nt like to make power over 5,000 rpm.

Been all thru the fuel demands/AFR stuff,no improvements.
3 different cams.
Checked valve springs,only a couple tho... shop said OK? 112 seat.
Checked exhaust back pressure .5lbs,nothing there.
Different octane fuels nope.
Hood off,nope.

So I`ve been told that the blower cant feed it and thats why it noses over like that.
So I took the blower off and installed a 4bbl. intake. Weiand Team G.
I had it in the attic from a package deal some years back. Man that thing is HUGE in the plenum,sits as high as the blower.
NO,,,, it NOT ideal for my engine but I ain`t buying something just to test.

1st trip. run surprisingly good till about 5,100 just gives up and pops once.
2nd trip 1st gear only DOWNHILL ,held it to the floor. Got to about 5,200 popped once and made it to 5,600.
Should have redlined and blown up.

So evidently the "tested" valve springs are not up to the job.
What are people using on a .509 hyd. cam these days?