Here is the camshaft with it's specs. I coated al lobes before installing with break in cam lube. Installation hhas to be done carefully to avoid nicking the cam bearings. Arrow and I have talked about the spec and what we think/hope it will do. Steve
If confused that is a mini simplex crank sprocket used to space the bolt out. at this point I had not replaced the lifter galley plugs. Take care moving the cam key as a new one is not supplied. My plan was to tap the lifter galley bores and pipe plug. Not sure you can see it but the oiling holes down to front main are so close to the front I was concerned about masking those holes. The tiny plugs won't be a problem as they covered by tensioner. Steve
We have talked about these before. Considering the distance between cam and crank it's great idea. It is also pure evil to install a cam gear with 7 key ways and the crank gear is a light press. I am going to degree the cam so this came off and I wiz wheeled the old one in half to retain cam while finding what set of key ways we'll be using. Steve
It is suggested the cam is so well made it will degree in dot to dot with a quality timing kit. I'll know soon enough. Due to lobe nose design this roller cam has to be degried in upside down. Normal or right side up you would look for lobe center line by measuring .050 either side of full lift #1 cyl intake. As I understand it we are now looking for base circle center line of the #1 intake lobe. Measured at .050 lift either side of base center. Add the numbers together deviede by two and hope it says put it together right here. I have some setting up to do before anything to show. Assembly has gone very well so far. I'm sure there is a torque figure for rotating a complete engine. Wish I had thought to measure torque as each piston was added. I'll try to remember to check now and after valve train is added springs! As each piston/rod assembly is added ring drag picks up. Once piston is in bore past rings the rod has to be guided to the crank journal. Having already lubed the bearing in the rod and journal I lube cap bearing and place. These are aftermarket rods rather than bolt and nut the bolt threads into the rod after passing though an alignment tube. It's suggested the cap be tapped into place rather than pull down with bolt. Once in place lube ARP hardware with ARP grease and hand tighten lightly tap to seat bearing recheck side clearance and that the rod moves and torque. Again rotate engine after each part is added, I know ring drag increases but sticking should never happen. Steve
I have a good idea where TDC is and mounting the wheel so zero is in a good place to mount a pointer. I make mine out of coat hanger wire with side cutters and a bench grinder a washer and bolt. Form it up and mount it close to zero. With the above dial indicator rotate crank past zero and to .050 and note the degree wheel. Then rotate the engine and piston back past zero and to .050 down the bore note then traveling back in the right rotation past and to .050 again. TDC is half way between the two and small adjustments can be made by bending the pointer. You have to have repeatable measurements. That was the next problem finding the center of the base circle. with the roller lifter on the well lubed cam. Steve
I shot this from several angles. The dial gauge has a very light spring to keep it in contact. Before installing the cam I lubed it heavy with cam break in lube. I was having trouble getting consistent figures. Again with the coat hanger wire. Old timers with recall when we added roller rockers and rev kits to short track engines. With a inner spring and retainer from a classic mini held in place by wire bracket. You can see the roller now cutting though lube for consistent and dependable reading. Oh well so much for the hype, the card calls for 110 installed and it's looking a lot like 112. I'll select the 2 degree advance option and run it again several times.
I'll be honest, I have been degreeing cams a long time. Taking measurements off the base circle has given me a whole new look at cam design. Sure a roller is different from flat tappet but how and when the intake opens has so much to do with low lift flow. The valve reliefs will handle way more cam than I'm running. Even with this very mild cam the intake valve is already opening while the piston is still coming up the bore. Steve
Just a different angle and that is my block handling chain should handle the load. There was a time when we would degree a cam in a couple degrees early depending on chain stretch to correct. Now with this tensioner and pre stretched duplex chain I'll put it where they ask. Then assemble with tensioner and check a couple more times just to be sure. Steve
PS And a Happy Fourth Of July may we never forget.
I'll just say dialing this cam in is not fun. After at least 5 to 7 changes I was no closer to in time than when I started. I went right back to dot to dot and 112 degrees. Being pressed for time ( someone has to grille ) I was sloppy failed to follow the logic. The instructions were appearently written for a different set and were of little help maybe a little harm. Still no retainers so I have time. Thinking it would be fun and interesting to make a triple gauge real stable and a rear mount for the degree wheel and start over. That way I will be able to watch crank degrees, piston travel, intake and exhaust all at the same time. Just two, watching the piston still coming up as the intake valve is starting to open is a hoot. I also want to look at this over lap issue. Off to make something. Steve