Best Timing

Printable View

08-09-2009, 08:17 PM
GMC400

Best Timing

Just curious what some thoughts on a good starting point on timing would be for an engine. Timing is locked out and is a competition transfer sled truck pulling engine.

I was thinking around 34-36 degrees to begin with.
Any suggestions?

Specs:

11:1 comp., 4" stroke, 4.155 bore (434sbc internally balanced), solid flat tapped cam: 3500-7500rpm range, 108LSA, 264,264 duration 0.50" 0.548,0.548 lift isky cam. Dart iron eagle platinum heads: 230cc runners, runners smoothed, 2.08, 1.60 (1.65 can't remember) valve. Victor jr intake with built in 1" spacer. MSD 8.5 wires. Hei distributor locked out, MSD 6AL box, Edelbrock 750 cfm tuned to engine. 7quart moroso pan, high volume oil pump.

Thanks, Joe.
08-09-2009, 08:49 PM
pat mccarthy

well i would try 34
08-10-2009, 06:23 AM
GMC400

Thanks Pat. I was just making sure I was in the right ballpark.
08-10-2009, 06:33 AM
pat mccarthy

yep you going to have a hard load on the engine. so i think that should do .your going to have to play with it some so take it ez
08-10-2009, 07:37 AM
GMC400

ok. Thanks again Pat. One more question, starting point on the plugs around .044"-.050" gap?
08-10-2009, 02:13 PM
pat mccarthy

i would gap them .045 HEI GM and .035 msd
08-10-2009, 02:34 PM
GMC400

Just to make sure I understood Pat, 35 with a MSD dist. and 45 with a GM dist.

Right now I'm running a GM dist. w/ MSD cap and coil.
08-10-2009, 03:00 PM
pat mccarthy

Quote:

Originally Posted by GMC400

Just to make sure I understood Pat, 35 with a MSD dist. and 45 with a GM dist.

Right now I'm running a GM dist. w/ MSD cap and coil.

if you run the msd box 6a or 6al or any msd box i would gap them to 035 .so gm dist with no msd box 045. the coil should not matter
08-10-2009, 03:02 PM
GMC400

Thanks for clearifying Pat!
08-10-2009, 03:32 PM
pat mccarthy

give it hell
08-10-2009, 06:45 PM
GMC400

Runs great. Had issues with the tach and shift light but all is well now. (the power wire came off in the dash) :LOL: