Valve train noise

[4eyedblonde]

I have a rattling valve train noise under load only. (clackity sound if that helps at all) Is this a valve lash issue or a detonation issue?
its a 440 with stell heads (#906),

 

[4eyedblonde]

ok, I think I've narrowed this to detonation based on other forum answers to similar noises. Has anyone plugged off the vacuum advance and solved the problem?

 

[Cranky]

There's a lot of things that can contribute to ping issues and timing can be just one of them. How bout telling us exactly what you have if you know the details. Compression ratio or at least your cranking PSI, initial timing setting and total....that sort of stuff....

 

[4eyedblonde]

There's a lot of things that can contribute to ping issues and timing can be just one of them. How bout telling us exactly what you have if you know the details. Compression ratio or at least your cranking PSI, initial timing setting and total....that sort of stuff....

I'm new to all of this, just reading stuff off the web etc. Compression ratio is an unknown. It was a 10.5 to begin with but I had to change out the heads and I think I've lost going to the 906 heads. Cranking pressure can't give you, timing is 22 degrees at idle. It runs fine at temp (always under 180), I just noticed the other day the racket coming from under the hood when I lay into it. Exhaust is pretty loud so it was drowning out the clatter. cruising around it's quiet.

 

[Moparsmitty]

22 degrees of initial timing is probably too much, but without knowing all of the variables I'm just guessing. I would back off the initial timing to about 12 to 14 degrees and see what that does. You should be shooting for 32 to 34 degrees of total advance and then tweak it from there.

 

[4eyedblonde]

22 degrees of initial timing is probably too much, but without knowing all of the variables I'm just guessing. I would back off the initial timing to about 12 to 14 degrees and see what that does. You should be shooting for 32 to 34 degrees of total advance and then tweak it from there.

Dropping the timing solved that clatter. I bumped it to 16. seems to be ok. Still the idle drops way lo in gear (600) no matter how hogh the curb idle is set Obviously the tming isn't the problem as it would do that when it was at 22 degrees...the mystery continues
Thanks for the tips

 

[73runner]

Does it idle smooth?

 

[4eyedblonde]

Does it idle smooth?

Well, yes but that all relative I guess. It's a lumpy cam. So yes it's idling in park at about 900-950 rpm and holds fine. I'm thinking maybe it's leaning out when in gear?? no black smoke

 

[mr. b]

I have a lumpy cam in my car and idling at 1200 in neutral if this helps any.bob

 

[4eyedblonde]

I have a lumpy cam in my car and idling at 1200 in neutral if this helps any.bob

I set it to 1200 earlier and it still drops low in gear and feels like it's going to stall out. I was told that 1200 is way too high for curb idle setting but I dunno. I'll try setting it up again unless anyone else has any thoughts. I was thinking it's leaning towards the air/fuel settings..maybe a bad fuel pump
Thanks tho Bob

 

[Lenny Arsenault]

Maybe you need a higher stall converter

 

[4eyedblonde]

its a 3500 stall converter now