I have a 95 NA I'm re-building, and I'm to the Point of checking the Cam/Crank Timing..

Being a nOOb this deep in to the Nissan Motor, I've hit a few snags that are not available by any Search Feature.. and I've hit a few different Forums looking for an answer.. so far no luck..

I'm comfortable with using a Dial Indicator on a Rocker Arm.. But these motors have a Valve Puck, nicely hidden below the Cam.. where no Dial Indicator can reach.. and the Lifter is a Hydraulic.. and the lifters are flat by now, so no rebound from the Valve springs..

I built a Fixture to hold the Dial Indicator on the Top of the Centerline of the Cam.. and Did my Indication that way.. It's 180 Cam deg off.. but other than that all looks good..



This allowed me to get a Timing on the Cams.. and the Cylinder 1 Bank is late by 10 Deg from the Other Bank..



But now I'm having Difficulty figuring out the Duration of the Cam. if I take the Duration readings at 0.050 lift, Duration is too short from factory specks..

What Starting Point is used for the Start of the Duration on the 300 Motor?.. 0.010 looks like it'll be Close.. I can figure out what will work.. but it'd be nice to know what factory is..



Thanks..

Cap

 

I sat down in front of the Motor and did some measurements and extrapolating..

If I start measuring the Duration at a Cam Lift of 0.010 Inches, I get a Duration on the Intake and Exhaust of 223 Deg.. The book calls for 248.. That's not it.. If I Start the Duration at 0.005, I get a Duration of 249.. So I'm good-nuff at 0.005 inch..

Then, doing some checking with the Known starting point, the drivers side bank is Late by 9 Crank Deg, and the Passenger side bank is Late by 15 Deg.. the relationship between the Intake and Exhaust on each bank is correct..

This is a '95, so it has the adjustable intake gears.. I can slide the bolts in the holes to get the Timing Perfect.. just might take a few tries..

For the Exhaust, I'll set up the Cam gear in the Index head in the Mill, and re-drill a Drive pin hole about 180 from the Factory Pin Hole. I will offset this by 5 Deg for the Drivers side, and 7 Deg for the Passenger side.. then if I put a new mark on the Outer rim of the Pully, to line up to the Belt line.. the Center 'Cover Washer' goes back on, all looks stock..

Cap