timing for Olds 455

[scarborough]

What's a good timing setting for a Olds 455 with Edelbrock cam it has Hei distributor with stock plugs, in process of changing the plugs to Ac Delco r46sx. my mechanic has the timing set at 20 degrees. just wonder is that's good.
also what brand oil filter are you guys using I like Ac Delco for my chevy motor. not finding a good Ac part number for the Olds.

 

[olds307 and 403]

Wix 51258 or Hastings LF222. You need to see what curve is in that distributor. Some have similar to a sbc or Olds points curve. Some have 14 to 16 mechanical advance built in. Get a dial back timing light, set the total around 34 to 38.

 

[pontiac guy]

How much total timing does it have? How does it start hot?

 

[scarborough]

How much total timing does it have? How does it start hot?

not sure of total timing. it fires up with no problem hot, pat of the gas maybe twice when cold. I did make a mistake, the upgrade plug will be r46sz not r46sx

 

[Rt Jam]

A fully tuned distributor will have at LEAST 3 things. Timing during cranking, idle, low load cruising and max power.

When is your engine at 20? With no vacuum advance during idle? If so, that's a tiny bit high but if the spread in the mechanical system is say 20, then you will have 40 at high rpm. Too high.

 

[olds307 and 403]

What is your compression ratio?