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Topic Review (Newest First)
11-08-2010 01:47 PM
PJ Dir Dr. Gears

Again, Supeer Thanks to all that assisted in this. 68 Nova SS, Thanks for hanging in there from the begining,well appreciated. Eric Nova, Thank you for your explanation on No. 6 & 1 Cyl @ TDC. I consider this a learning experience & hope to share this info with whomever may need . Thanks Again Guys. AFSOG.
11-07-2010 09:55 PM
68NovaSS So, your #1 cap tower is at 11 o'clock? If you still have plenty of rotational adjustment, it's OK to leave it, myself, I'd rotate it 180. If you do, make sure you don't turn the motor over while it's out, move the wires clockwise around the cap, fire it and time it.

Eric, if his #1 wire is at 11 o'clock, my suggestion would only move the #1 tower to the 5 o'clock position, then rotate the wires 180 as well. What am I missing here?
11-07-2010 09:52 PM
ericnova72 When you time the cam to the crank correctly(dot to dot, cam dot at 6 o'clock and crank dot at 12 o'clock) you are at TDC firing #6 cylinder, at the same time it is TDC exhaust stroke on #1 cylinder. As you have found, #6 cylinder corresponds to 11 o'clock position on the distributor cap. If you pull the distributor now and turn it 180 it will put your timing 180 out of time and the engine will not run. You have it correct right now, just final time it with a timing light.

The 6 and 12 dot to dot is just for installing the cam timed correctly to the crank, not the same as distributor timing, they are two seperate things. If you wanted to put the distributor in after installing the cam and have it pointed at #1 cylinder, you would first need to turn the crank and timing set/cam so that the crank dot is again at 12 o'clock but the cam dot is also now at 12 o'clock high.
11-07-2010 09:32 PM
PJ Direct Gears

68 Nova SS, I am Elated to report all Systems are go. Since Crower Cams of Chula Vista, sold me this kit, I decided to contact Jerry at Crower. His advice to all this was "Go for it". Direct Drive Gears will not damage Cam, Rollers, Springs, Lifters nor Pushrods. I am also happy to report, although Engine was set to TDC, Rotor Cap ended up pointing towards the 11 O'clock position (Facing Eng). Did as you stated, Installed Cap & Fired it up. Cranked like a Champ on first attempt. Ran car most of this weekend, Zero leaks & appears to be settling in nicely. My question is this: Should I leave "Well enough alone" or should I pull Distributor & rotate 180 ,so Rotor points to No.1 Cyl? Thanks.
11-03-2010 04:28 PM
WDCreech I changed to the Aussie chain, but I have a belt drive on my other engine.
11-03-2010 03:16 PM
PatM And, did adding a belt driven supercharger help to mitigate the spring failure, or did you miticate the failure just by changing to a roller chain?
11-03-2010 02:19 PM
WDCreech Pat, I don't understand why, either. I had been told that about 15 or 20 years ago and after running a Milodon gear drive on a hydraulic cam for 4 years, without problems, I thought it was BS, but when I put in a solid roller, my springs went away. Not once, but twice in one summer. They weren't cheap springs, either. They were expensive springs matched to my roller cam and the engine never saw over 6400 RPM.

11-03-2010 01:14 PM
PatM WDCreech -- I don't understand how a blower belt between the crank and the blower would dampen harmonics generated by the gear drive between the crank and the cam. I do understand how the belt could improve damping on the crankshaft itself. It might help the crank particularly if the HD on the engine was more rigid . . less compliant. Please help me to understand how the blower belt would help reduce harmonics on the valvesprings.

11-03-2010 06:57 AM
Originally Posted by afsog
Does anyone know for sure if you can or cannot run a P Jackson Gear Drive with Solid Lifters? Thank you.
It appears to me that it is not a case of can or cannot, it is a case of the combination possibly using up valve springs due to harmonics. Randomly remove a spring for testing periodically is what I'm taking away from this thread.
11-02-2010 08:54 PM
afsog Well F-BIRD'88, what do you have to say about WDCREECH Statement? "Stay away from Cars"? As stated previously? To SS Nova, Thank you for your expertise. Appreciate it. Ok Guys, so what is it? Does anyone know for sure if you can or cannot run a P Jackson Gear Drive with Solid Lifters? Thank you.
11-01-2010 10:20 PM
WDCreech A gear drive and solid lifters don't mix unless you have a blower belt to dampen harmonics. I ran a gear drive for several years with a hydraulic cam, but when I switched to a solid, I used up two sets of valve springs over one summer.
11-01-2010 08:33 PM
68NovaSS It should be just like changing a chain. If aligned correctly, it should fire, you'll have to check/adjust the timing of course. The only ajustments you might need to make is for clearance between the button and timing cover. You'll need access to the cam to move it back and forth, that means intake off and make sure you don't slide the cam out too far.
11-01-2010 08:21 PM
PJ Gears.

Again Super Thanks! Maybe I am not to good at understanding the whole answer but, I did key in on your first sentence! "You're OK with 12/12 with #1 @TDC Both Valves closed.
QUESTIONS: How will this effect the Initial Cranking of Eng & setting Timing ?Will any other adjustments have to be made prior to Cranking? Thanks Again.
11-01-2010 05:34 PM
68NovaSS You're OK, with 12/12 with #1 at TDC, both valves closed, you're ready to fire #1. The reference on the sheet regarding "TDC" in both alignment positions, is only the pistons are at TDC, period. In one, position cyl #6 is ready to fire, in the other #1 is ready to fire.

Would be at the top of the exhaust stroke #1, top of compression #6, which it is when the dots are cam 6 crank 12 (together).

I'm not great at explaining it, but you get the picture?
11-01-2010 05:18 PM
PJ Gears.

Misprint!! Cam Gear at 12 O'Clock. Crank Gear at 12 O'clock.
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