Ignition Timing on a 440!

[emonster6x]

I need to know what you guys time your 440's with a bumpy cam to.

I am using a Mother Thumper with 290 degrees of duration.

Stock Exhaust manifolds, Dual plane intake, Std HEI Mopar ignition, Holley 750 carb with vacumn secondaries.

Please let me know......

Thanx!

 

[Cranky]

What's the compression ratio? Bigger cams usually bleed off cylinder pressure in the lower rpm range so a bit more initial usually helps. I usually start with around 15 degrees initial and give it what it likes for total.

 

[emonster6x]

I believe the comp ratio is stock probably 10:1? It is a 1970 Dodge coronet.

 

[Cranky]

A 70 4 bbl motor according to my books should be around 9.7 and probably closer to 9.5 Book says 2 1/2* BTDC on the timing but I've never had any big blocks run worth a damn with timing as soft as that....even back in the day.

 

[bigmanjbmopar]

ka thunk ka thunk @ 9.5 lol 10-15? what's your total now? mine runs at 12 inital and 35 total@3000 rpm

This your cam?
http://www.compcams.com/Company/CC/cam-specs/Details.aspx?csid=1500&sb=2

 

[emonster6x]

My is this:

Nope it's this one!

http://www.compcams.com/Company/CC/cam-specs/Details.aspx?csid=1524&sb=2

 

[70redbee]

Nope it's this one!

http://www.compcams.com/Company/CC/cam-specs/Details.aspx?csid=1524&sb=2

That one says it is for a Ford. Can't be right, check again.

 

[emonster6x]

Sorry, this one!

http://www.compcams.com/Company/CC/cam-specs/Details.aspx?csid=1496&sb=2

anybody got an idea as to what this one should have for ignition timing?