HOW TO DEGREE A CAMSHAFT Reher Morrison racing engines

I'm Tony Claridge if you called with technical questions I may have been one of the ones you call to you today we're going to show you a part about doing cam timing something that we've written about in length in our book we still get a lot of phone calls so I thought we would kind of lay out how we do it here and eliminate some of the myths about cam timing so this is what this whole project here is going to be about first myth I want to end is when you put a motor together and you line all your components of dot-to-dot that's what you've done you lying all your components up dr. dot that is a starting point for degreeing in the cam that does not mean the cam is heads up it does not mean it's what the lobe separation on your cam car says it is strictly dr. dot your Tim companies will all state you need to degree in your cam and here's the reason why every component I've laid out here has variables they have an area of range they can hit on this upper gear for this lower gear to the cam button to the crankies so you can have all these components only be off a degree of two and then this can be 10 degrees motor wouldn't run very good 10 degrees cam companies try to take advantage and save the base circle of the cam and that's why the dial is located where it's at this button might not be perfectly if everything was perfect where it would wind up 1:13 there's a variable involved so another reason you have to degree in your camp if you're going to do this otherwise you're just laughing everything up dr. doc you haven't done anything but get to a starting point in your project I use this we're also wheel for the simple reason my old eyes these big numbers make life a lot easier but it also has the numbers of which you're going to when we start getting in Green that are in black that will help you count backwards to help you degree come up with your final numbers we do this off of 50 off method if you look at your cam cards they'll have advertised and then they'll have that 50 we degree in all our cams all our data is based off at 50 so there's several things you need the degree in the cam some people use a hard stop to find TDC that's the first thing you have to do it's important to find TDC and keep everything locked down until you get your pointer and balance you're off because everything is based off this first step you make your piston to valve your cam timing your ignition timing if somebody bumps your pointer are you loosing your pointer or whatever happens it throws everything off so there's a very important project I do do it a different way than the hard stop to find TDC but we'll get into that later gotta have a bridge that I have a dial indicator degree with this is the part you're going to need if you're going to degree in your cam if you're doing a can change with the head zone you have to fight bills I don't know they even sells them but we have a spark plug with a shaft through it to make a hard stop so you can even do this chain scans and degree it in with the motor with the heads already humming okay when advancing and retarding the cam Jessel makes it real easy they not only have this adjustable gear they have it written all here for you advance makes life a lot easier take our billet gear we drill a hole always have them drilled and ready for our builds and put a zero button in them this particular gear cent comes with a advanced feature on it says it's 4 degrees never assumed as I'll say dr. dot is an assumption so it would be advanced if you wanted to advance it four degrees you might advance it four degrees it might be six it might only be two so you still have to check it sometimes it's a four-degree button advancing it sometimes it's a four-degree button you so that's kind of why this is important big difference in a motor if it's 8 degrees ok here we're going to demonstrate the hard stop method for 5 at TDC just gently roll the motor over clockwise we'll see where it stops stops at 20 ok now we'll go counterclockwise and we'll see where it stops stops at 19 so we need to split the difference 19 and a half check make sure that's what we wound up with 19 and a half so that should be perfect TDC and we need to protect this pointer we're now ready to set up or portion of this to start the green in the cam I got a set of checker lifters here I use light oil in this case wd-40 because I want to make sure nothing affects these lifters going up and down I'm about to set up my dial indicator so what I'm going to try to do here is get the lifter at max hike so that I can make sure my dial indicator doesn't bottom out I'm going to use a push rod in this case with that set up I still have plenty of travel this is the two inch dial indicator so I'll have plenty of room most people will only have a one inch so your amount of room will be less but you need to make sure you've got room on both ends bottom and top so if you don't get a false reading we have plenty of travel there at the bottom so nothing nothing is going to give us a false reading from this standpoint okay when we start the green in the camp these are the numbers we're gonna look for open at 50 close at 50 add these two together then add 180 that will equal our duration at 50 we will then take that number divide it by two subtract the open at 50 number and then that will give us our intake center line we will then go to the exhaust side of degree in the can same procedures we're gonna check open at 50 plus closed at 50 plus 180 then that will equal our duration at 50 we will then divide the duration at 50 by 2 and then subtract on the exhaust side we subtract the clothes at 50 and then that will equal our center line we didn't take our intake center line plus our exhaust center line add them together divide them by 2 and then that comes up with the cam lobe separation okay we now want to be on the back side of our lobe so that we can set the zero on our dial indicator and what we're going to be looking for is to come up this is where the term 5050 off comes from so we want to make sure it stays on 0 until it heads to the positive to the clockwise or positive then we're coming up on 50 and then we'll come around here in my degree in this case is we're gonna call this 30 the next number we're going to look for which I had told you earlier was we wanted to know when I'm doing my belt sheet I wanted to know left after TDC so that's 50 that would be a hundred thousandths and now we're trimming up I'm 10 degrees so we're at 205 there's 300 there's 400 494 left ok now we're going to write that number down now we'll back up we'll keep turning forward I mean clockwise and there's 400 300 200 100 and now we're going to get our closing in at 50 now we come to our wheel this is where you use your black numbers for intake closing it's clearly marked a good thing about this degree wheel 71 2 and 1/2 we're gonna do the intake numbers open it 50 plus closed at 50 plus 180 will equal our duration at 50 in this case 283 there's your duration now we divide it by 2 we come up with this number 141 point 5 then we subtract the open at 50 which was 30 point 5 and that gives us an intake centerline of 111 so making sure it stays on zeros and it starts to head toward 50 just like within pate this is a belt drive we got to back load it there it is still 2 degrees back loading okay coming up with 91 and a half exhaust is different from intake on the next step next step on exhaust will be getting maximum load lift there's one hundred two hundred three hundred four hundred eighty five that's the load lift forty now let's find our lift it cockpit clothes there's two hundred one hundred and we're looking for fifty coming up okay we've got a back load it it is thirty thirty seven and a half for the exhaust we get the open number at fifty this is ninety one point five plus the clothes number at fifty plus 180 which equals 309 duration at 50 thousandths we then take that number divide it by to come up with one fifty four point five then we subtract the clothes number at fifty which is thirty seven point five and we come up with 117 exhaust centerline now to do your camshaft lobe separation you take the intake center line which was 111 the exhaust center line which was 117 add them together then divide them by two and you come up with a 114 lobe separation which is why we're running the intake number since we generally run two to three up while we're running it at 111

Channel: Eagle Hyzer

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Id: HCJpdEez318

Length: 13min 7sec (787 seconds)

Published: Mon Jan 28 2019