I am trying to figure out how much total timing I need to be running . I have a stock bore 350 with 3.75 stroke crank , 10.2:1 compression dished pistons , and Edelbrock dual plane intake. My cam is a Crane hyd roller .509/.528 and 222/230@.050 I am running an MSD dist. and Blaster2 coil. Currently in a 82 Berlinetta with 3.73 posi and 700-4R with a 2400 stall. Heads are GM Vortecs cut for high lift with 1.94/1.50 valves with springs matched to the camshaft. 125lbs. closed / 345lbs. open pressure. Any help would be greatly appreciated.

 

32-34 total usually for vortecs, but every engine is different.

Put the black limit bushing and one light silver and one blue spring in the distributor. You should wind up at 14-16 at idle.

 

Didi some research and found that ,according to MSD, i need to retard the timing and use the Heavy springs on the advance because of "higher cylinder pressure" and over 9.5 compression to reduce detonation. Does this sound about right ? Also thanks for the total timing reply. Now I'm down to how fast I should be advancing.

 

No, set it up the way I said. Forget about the recommendations in the instructions.
You do not have high cylinder pressure with 10.2 compression and your cam.
And even it it did have detonation it would be due to the total timing, not the timing curve.

 

Okay. So I shouldn't worry about detonation with my combo ? I am just trying to be thorough with this build . Several of my SBC "How-To" books all swear by the over 9.5-10 CR will result in detonation. But I have ran alot of crazy stuff when I was younger and have never had a problem . I will pull the distributor later and try the silver/blue light springs and the Black bushing. The black one says it limits me to 18 degrees , so that won't be to little will it ?

 

No its is not to little. You want the least amount of advance so you have more timing at idle to smooth it out. The only time you have a chance of knocking with this setup is with a really heavy car. Also do you have a vacuum advance on the distributor?

Just out of curiosity, how old are those books you have?