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Discussion Starter #1
As when building my engine, I'm a newbe in this area too.
So timing gurus, your help is needed!

I have set my timing to 35 degrees just to have something to begin with.
The old engine was working well at that timing.
But with the 11.3 comp, I guess the timing should be changed, retard?

Right now my distrubutor MSD 8454 (same as MSD 8571) have the advanced stop bushing in silver.
For the advance curve I have one thin light silver spring + one light blue spring.
Don't have any idea if this is a good or bad setting.
 

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Discussion Starter #3
I only use Shell V-Power 99 octane, similar to US 94-95 octane.
I think it's the best that can be found on regular gas stations.
 

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Do a search for timings posts by LARS :thumbsup:
 

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going off what you have posted in the signature line, i would go with the following. set your final timing to 36* (with vac advance disconnected) and put the 18* (should be MSD black) limiter bushing in the distributor. this will give you 18* initial timing. the main reason for this is the cam you have. it has some pretty big numbers for a 388. i run a 244/256 @ 0.050" in my 406 with .600 final lift, creating a very lopy idle. my heads are also aluminum and running 11.2 comp ratio. i can easily run 90 octane with out detonation at sea level. the big cam bleeds cylinder pressure at low RPM and the extra intial timing helps throttle responce and carb signal. this also makes it easier to tune the idle circuit. this is also all contingent that your starter can pull the intial timing, most can. also set it so that you get full mechanical advance by 2500 rpm.
 

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You might be on the edge.

Here is a little read that may get you a few option to think about.

http://www.popularhotrodding.com/tech/0311_phr_compression_ratio_tech/

One addition to their 15 item list is water injection.

:D
You don't understand "dynamic compression ratio" He has a big solid roller cam. My 383 is 11.24 Static CR with less cam and it runs fin on our California 91 octane max. My real hot rod motor is 11.8 and it also runs fine:laughing:

Nobody can really state the perfect timing for somebody else's motor. Way to many variables. You have quench area height, volumetric efficiency at different rpm, exhaust dilution, combustion chamber type. Both of my motors have initial of 17-18 degrees and total of 32-33 all in @ 3200 rpm. My Dart heads have fast burn technology and I use about .040 quench to get a higher burn rate. With my higher compression and free flowing 3 inch exhaust I have very little burnt gases dilution to slow down the burn rate. I also have used the adjustable vacuum advance to limit it to maybe 5-8 degrees cruising under lite motor load like 150 Kph
 
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