OK guys, have decided due to the amount of work has been done to this engine and the fact it's been apart quite a few times, machined etc.... I better setup the initial exhaust cam timing before it goes in and hits the dyno. Has anyone had any joy using these cams and variable gears and what advance/retard did you setup on dyno? Obviously these cams are setup to have a 4 degree advance on them from when they were first designed to apparently counter the lack of breathing mods available at that time. I'm thinking setting them up at exactly same spec as the camsheet with the 4 degree advance, lock them off and Mark as a baseline and then if there appears to be any gains to be had from advancing further or retarding back to a true zero advance (reduce the camshafts built-in 4 degree advance) we can have a crack after the initial run-in. Thoughts??
No getting a tuner. Thinking best to zero it in and set it up neutral and see what they want to do. Just thought I'd see if any boys on the forum have had good/bad experiences and results
Will be interesting to see if there is any major differences in the intake cams considering I had to get a replacement cam after my little install fu+?up
Yep set em to 0. And take it in. Cams are affected by head port, turbos, inlet manifold porting etc. Unless someone has exact same setup. What works for one setup wint work for another.
I run 400+ but just used stock exhaust gears. Didn't tbh see the merit at the time of running adjustable.
I was just reading Ron's update on the silver bullet the other day actually. Gained nearly 600rpm of power curve with 4degs. Lost a smidge of peak power.
Jwt cams have a +4 advance in them . Dial them in - 4degrees exhaust side. Designed to help spool bigger turbos back in the day but with all breather mods now dial in to what would be 0 . .
I have dialled out the +4 advance on my R5 cams. According to Greg @ SZ in most cases where there are sufficient breather mods he finds backing out back to 0 nets quicker spool.
The main reason for adjustable cam gears is to correct cam timing relative to the crank shaft. If your head and/or block were machined as part of the rebuild process your cam timing will have changed as the cam gear is now closer to the crank gear.
i don't know if i would be going off the markings on the cam wheel anyway. If it were me, I'd be setting up the dial indicator and degree wheel to get the timing to exactly match the cam spec sheet.
wow thats a pretty big difference. though looks more like its moved 450 rpm than 600. am i reading that wrong? if you're looking for area under the curve, thats going to improve drive-ability.
