I have a 360 with a 428 crank, Comp Cam RV grind ,ported heads ,billit shaft stands ,RPM manifold ,Edelbrock HO pump,holley regulator , 570 Holley,(I have downsized the jets) ,MSD 6AL(4100 RPM limit ), MSD ready to run distributor.I live at an altitude of 6200 '.It's a daily driver so everything is done and over by three grand (sometimes a little more if I am feeling lucky). I talked to MSD and curved the distributor to their specs . It starts right off in the A.M. It is harder to start later in the day .It smells like it is running rich . I had a recurved Duraspark that the vac advance was frozen .so I ran it that way with ports pluged .It ran OK .I am currently running at 14 degrees initial. Any insight about curve , initial ,total timing, or what ever would be appriciated ,

 

Sounds to me like you have a 410.

Are you referring to a restart after it has been run a while? Do you have an aluminum intake?

The hot restart issue was resolved for me by adding a 1" phenolic spacer under the carb.



John

 

Actually it's a 417 or18 since it got bored .30 to clean up the cylinders. It is the Edelbrock RPM manifold with a fresh spacer. I'll check into a thicker spacer.

 

Since you're not staying up in the "total ignition advance mode" very much(you say your rpms are usually between idle and 300o rpm), your initial timing and actual curve are quite significant important. If you have the intial timing set too retarded, and you stay in that rpm range a lot, your engine will run hotter than normal (and burn more gas). This extra heat (along with your elevation) could be contributing to vapour lock/percolation after your engine is shut off for a while. Basically, the fuel in the carb, and in the manifold evaporates away, and the next time you try to start it....a lot of cranking is needed.

I'd try increasing your initial timing about two degrees at a time and listening for "pinging". If it's a standard trannsmission, try lugging it from about 1000 rpm to 3000 rpm in high gear and listen for pinging. If none, try another 2 degrees advance.

Once you're done, check your max timing and make sure it is 38 deg or less.....even down to 32 is probably OK. If it is over 38, you need to adjust the limit stops in your distributor.

Of course....if that spacer fixes everything.........I just wrote a whole pile of uselss info......LOL. Yeah....try the space first!!!

 

You have overlooked a very important item that changes his tuning parameters that means 38° isn't gonna work.

"I live at an altitude of 6200 '."

That means lean is a normal condition, plus low compression caused by thin air. Your 32° is a better max number to be working with. But for his application a 3500 rpm max timing in is a good idea.

 

I didn't overlook it. I didn't know it! So, at higher elevations, max timing should be reduced.....I learned something new! Good point Bear.