Hey guys...Keep in mind he is running VORTEC heads. They have fast burn chambers and do not require as much timing as conventional heads. 28 degrees, maybe 30 is all the timing you should run with these heads.

Bob

bobl
i know the cocept of vortec heads but am not too familiar with them. what happens if you run the timing higher?
thanks, Fran

When the HEI first came out the plugs had as much as a .060 gap to take advantage of the higher energy spark. The Vortec plugs need the .045 gap to optimize their fast burn. I can apreciate the down to earth idea of motor cover off under power, trying 1 degree at a time to see what your engine thrives on for the true advance setting. Top speed will tell you the bottom line answer you are looking for.
Neal(a wrencher with never enough hours on the water)

I CHECKED FUEL PRESSURE AT WOT AND HAD NO LESS THAN 6 PSI.I CHANGED THE PLUGS TO THE R43LTS RATHER THAN THE R43LTSM.I DONT KNOW IF THE EXTRA LONG EXTENDED TIP OF THE LTSM WAS MAYBE PART OF THE PROBLEM.I HAVE NEVER SEEN PLUGS WITH THAT MUCH OF AN EXTENDED TIP.I KNOW THEY SHOULD RUN COOLER WITH THE EXTRA REACH BUT THEY SEEM TO HAVE A LOT OF METAL HANGING OUT THERE.I CHANGED THE JETS BACK TO 107 PRIMARY WITH A 37 POWER STEP AND A 104 SECONDARY.MY DETONATION APPEARS TO BE GONE.I SUSPECT THE PARTIALLY CLOGGED NEEDLE SEAT SCREEN.I ADVANCED THE TIMMING TO 6 INITIAL AND 30 OVERALL WITH NO INCREASE IN SPEED OR RPM.IT SEEMED TO RUN A LITTLE ROUGHER AT LOWER RPM 2500-3500.ANY EXPERIANCE WITH TIMMING AND THESE HEADS APPRETIATED.I KNOW OF A FEW POPULAR ENGINE BUILDERS IN MY AREA THAT HAVE HAD MELT DOWN PROBLEMS WITH THESE HEADS.WHEN I GOT THE BOAT OUT OF THE WATER I CHANGED THE PRIMARY JETS UP TO 110 BECAUSE IT FELT JUST A LITTLE LEAN.I WIL EXPERIMENT WITH TIMMING CAUTIOUSLY AND LET YOU KNOW HOW I MADE OUT.I CHECKED THE PLUGS AFTER EXTENDED CRUISE TIMES AT DIFFERENT RPMS AND THEY ARE JUST BARELY STARTING TO COLOUR.THEY DON'T APPEAR OVERHEATED.ANY IDEAS AS TO WHEN THE POWER VALVE SOULD SHIFT TO THE POWER STEP.RIGHT NOW I'M USING THE 10''VACUUM SPRING (SILVER)AND THE POWER VALVE SHIFTS TO THE POWER STEP UNDER ACCELERATION BUT WILL NOT STAY OPEN UNTIL AROUND 4000 RPM.THE VACUUM SECONDARYS OPEN AROUND 4500.DOES THIS SOUND RITE.I WOULD HAVE THOUGHT THE POWER VALVE WOULD OPEN SOONER.IS THERE MAYBE NOT ENOUGH LOAD ON THE ENGINE DUE TO PROP SIZE.IT'S TURNING 5400 RPM RIGHT NOW.

THANKS FOR THE INPUT