307 non computer controlled timing.

[olds307 and 403]

I have removed and blocked off the EGR on a Olds 260, a few 307's, a couple of 350's and a 403. Aggressive timing on them all, no signs of pinging on 87 octane. I tried it 9.6 to 1 with 204/214 cam on 91, I needed to restrict timing a lot.

 

[Jimmy]

Did you swap the carb too?

Yes q jet with electric choke

 

[TURNA]

Disconnect the vacuum advance and plug the port on the carb.

It is hard to see the numbers on the 307 timing tab

Set the timing to the center of the timing tab that should be 12*.

Lock it down reconnect the advance and go from there.

A hair more in either direction to fine tune it to your engines liking.

You may need a timing chain.

If you pull off the fuel pump you can check the slack in the chain.

Mine had a ridiculous amount of slack but it held the timing.

I was glad I caught it before it jumped a tooth or broke.

 

[TURNA]

Oh and


JIMMMMMMMMMMMMMMMMY

 

[Jimmy]

Disconnect the vacuum advance and plug the port on the carb.

It is hard to see the numbers on the 307 timing tab

Set the timing to the center of the timing tab that should be 12*.

Lock it down reconnect the advance and go from there.

A hair more in either direction to fine tune it to your engines liking.

You may need a timing chain.

If you pull off the fuel pump you can check the slack in the chain.

Mine had a ridiculous amount of slack but it held the timing.

I was glad I caught it before it jumped a tooth or broke.

Thanks TURNA I think that will be the approach I take. I am pretty sure the timing chain is ok it was replaced a couple of years ago when I had to rebuild the engine. I swapped the distributor and carb (which looks like its on life support with all the crap plugged into it) to try and simplify things. It runs a lot better, but still has some issues that appear to be timing related.

 

[Jimmy]

With no egr you'll have to back off the timing a coupld of degrees. The egr cools the combustion chanber and without that cooling the advanced timing can cause pre-ignition due to the heat.

Thanks I think I'm gonna set the timing to 12 degrees and try It. If it still doesn't go right it wont be hard to reconnect the EGR valve.

 

[DoubleV]

Why set it at 12? Yes it'll run like that but why would you willingly set it so low? 32 total advance and only 10 vacuum advance is all too low for your engine. You're just leaving power, milage, and even idle quality in the table.

With all your timing in by only 1800, maybe you're getting some mechanical advance at idle which is not what you want. Idk what you're running exactly but perhaps 1 heavier spring would slow down your curve a bit.

 

[TURNA]

Why set it at 12? Yes it'll run like that but why would you willingly set it so low? 32 total advance and only 10 vacuum advance is all too low for your engine. You're just leaving power, milage, and even idle quality in the table.

With all your timing in by only 1800, maybe you're getting some mechanical advance at idle which is not what you want. Idk what you're running exactly but perhaps 1 heavier spring would slow down your curve a bit.

OK then set it to 22 degrees run 90+ octane and don't try anything else.

That's it done . Do not ever try anything else. Do not experiment with anything.


NEVER EVER TRY ANYTHING!!!!!!!!!!!!!

 

[DoubleV]

Theres no need to try things that are obviously not correct. I'm curious where you're getting your numbers from TURNA? Did you just pick a number and say 'try this' and not put any real though into it?

Stock base timing with CCC was 20. Total is around 35ish. Most bump this up a couple degrees. Why should it now be much lower than this?

 

[pontiacgp]