Degreeing a camshaft and Cam timing.

[claymore]

This is more of a nice to know information type post just so members can have some interesting information.

Again not really a DIY but this info CAN be used on your Jazz if somebody makes an adjustable timing gear for the Jazz.

First this is not a DIY as there are too many different kinds of members cars to pick one out for a real DIY but I'm going to include the regular disclaimer just to be on the safe side.

Disclaimer: The following is provided as a GUIDE ONLY, and neither myself, nor Honda Fit Forum take any responsibility for the outcome of someone else doing the following. You follow these steps at your own risk!


OK now that all the start up junk is out of the way we can get down to business. the first thing we have to cover is "just what is degreeing a camshaft"? (we will get to cam timing later). It's really very simple to talk about but takes a lot of work and patience in the real world.

Very simply degreeing a cam is using a mechanical tool called a degree wheel and other precise measuring equipment to measure the specifications of your camshaft, crankshaft harmonic balance key way, key, and your stock timing indicator to a precise degree of measurement to make sure your parts precisely meet specifications by Honda or your camshaft manufacturer.

Whew all that big talk means that you are checking your parts to see if they are made and installed the way they should be VERY SIMPLE.

http://img.villagephotos.com/p/2005-12/1118998/valve.jpg

This is a degree wheel and it's just a circle, in this case made of metal, and as you all should remember from math classes a circle has 360 degrees in it so the secret of a degree wheel is that it just shows all the degrees in a simple tool that can be attached to your engine.

http://img.villagephotos.com/p/2005-12/1118998/valve2.jpg

They come in all sizes prices and can be made from all different kinds of material.

http://img.villagephotos.com/p/2005-12/1118998/valve1.jpg

They can be simple with just degrees or have other indications on them like this one showing when the valves should be open or closed.

http://img.villagephotos.com/p/2005-12/1118998/valve3.jpg

If your a real skin flint cheapo you can even download one and print out one from the net. BTW it makes a neat wall decoration.

Now that we know what it looks like how the heck do you use it? The best advice is to use the biggest one you can get that fits into the space where you are working. As some of you remember from the boring math classes the larger the circle the more accurate the degree markings and that's why you are doing all this work to PRECISELY check measurements.

You can degree a camshaft while the engine is in a car BUT with a front wheel drive, transversely mounted engine, the room you have available to put on a degree wheel is severely limited so you end up using a very small degree wheel and that limits how accurate of a job you are going to do.

Tools needed:

Degree wheel, bigger is better.

Dial indicator .500 or one inch travel with a magnetic base or solid adapter that allows the indicator to use a bolt hole on the engine to solidly mount the indicator.

Pointer can be homemade or bought.

Positive piston stop again can be homemade or store bought.

Getting started

Now that you have collected all the tools you need you have to put the degree wheel onto your crankshaft.

There are a couple of ways to mount the degree wheel, one of them is to buy a ratchet adapter which is just a part that allows you to quickly put the wheel on.

Or you can go the quick and dirty route and get an adapter that uses the stock bolt in the crankshaft pulley.

Either way if the degree wheel is removed for any reason TDC must be found again.

The best and easiest way to degree a cam is when you have the engine out of the car and on a bench.

http://img.villagephotos.com/p/2005-12/1118998/valve4.jpg

This photo shows the wheel installed using the stock crank bolt location with a new longer bolt. Any method is fine as long as the degree wheel CAN NOT MOVE OR SLIP OUT OF POSITION.

It also shows a new pointer made out of a bent up piece of wire which is OK is long as you are not clumsy like me and never hit that weak pointer and knock it off it's position and have to start over. I prefer to make a pointer out of more sturdy metal so if your kid brother comes into your build area messing around it will be much harder for him to accidentally grab the pointer and mess you up. Any thing that points to the wheel and doesn't move is OK.

Now for the most difficult part of the job "finding TDC". In the photo above the dial indicator is the white face thing above the piston with a tail coming out going down to touch the top of the piston. All the knobs and metal rods are just parts of the set up holding the indicator in a stable precise position.

All the gauge is doing is measuring when the piston is at the very very top of the cylinder bore at the precise instant that it's not moving either up or down at the point where the piston is at the beginning of the cycle.

A tool called a positive stop can be used CAREFULLY with the head off. The stop is just a hunk of metal that has a bolt or rod screwed into it and holes or slots milled into it.

http://img.villagephotos.com/p/2005-12/1118998/P238_239.jpg

This photo is NOT a piston stop but it's the closest thing I could find. It looks almost the same but the part sticking out to the bottom left on a real piston stop would be much shorter and would be just the rounded end of the bolt not all that split part, and there would be bolt holes or slots in the big piece that the bolt is threaded into.

Finding TDC

It is just bolted onto the top of the block and screwed down carefully until the bolt sticks out just enough to hit the top of the piston. now you can see why you have to be careful with this bolted in place the piston can come up and hit the stop and if it's not adjusted carefully or you crank the engine too fast and it bumps the stop at speed something is going to BEND.

OK so you have bolted the piston stop to the top of the block and SLOWLY AND CAREFULLY using your hand on the flywheel or a wrench on the crankshaft bolt (without bumping the degree wheel) move the crank in the direction of engine travel until the piston comes up to the top of the bore using just your eye to tell stop when the piston is all the way up. then slowly and with no force screw the bolt in the center of the piston stop down until it just touches the top of the piston and lock it off in that position. so now you should have the piston all the way up in the bore with the stop adjusted so it can't travel any more in that direction (positively stopped).

Now is the time you get to use your dial indicator. Mount the indicator to the top of your engine with the magnet or bolted down. After you have read the handbook or have gotten some instruction in the use of the indicator put the end of the indicator arm onto the top of the stop piston and adjust it so you are reading zero.

Install indicator to hit the piston near the center to minimize the effect of piston rock at TDC. Turn the crank through TDC in normal direction and 0 indicator at the highest reading. Now turn the crank the opposite direction of engine travel (backward) until the piston stops on the other side. Write down what your reading is on the indicator.

Now go back the other direction and when you get to a 0.100 reading which will then be 0.100 BEFORE TDC. Now go back in the other direction until you get a reading of 0.100 which will be 0.100 AFTER TDC so you now have Two readings one BTDC and one ATDC one before and one after Top dead center.

TDC (which is what we are looking for) will be half way between these readings. You could use any reading to get to this result like 0.500 as long as you remember which reading you are using.

Now that we know where TDC is what the heck do we do now? Well we know where TDC is but if you think back I have not yet told you which degree to start with on the degree wheel. We have to adjust the degree wheel and pointer. First carefully move the crank until the piston is at TDC by watching the indicator and moving the crank SLOWLY until the reading is between the two 0.100 readings. Now the piston should be right at the very top of the bore in the spot where it is neither going up or down known as TOP DEAD CENTER or TDC.

Adjust your pointer to read 0 at this point. You can either move the degree wheel which is more involved or bend or adjust your pointer to point exactly at zero degrees. Top Dead Center is now accurately known. This is a very important step because there is a point a few degrees before and after TDC when the piston moves very little. This method measures the same point on each side of TDC where piston movement is much greater per degree of crank rotation than at TDC.

Once you find TDC and have adjusted your pointer be sure to REMOVE the piston stop so you won't have to worry about turning the engine too hard and bend something OUCH.

[claymore]

You can do this process with the head on but you have to have an extension for the indicator arm so you can put it into the spark plug hole. Set the indicator up pointing down into the spark plug hole until the indicator is onto the top of the piston. Set the indicator to zero and go through the one direction to the other direction set up process again. The reading from the opposite rotation is recorded and TDC is halfway between your first 0.00 reading and the reading you get on the other side.

Whew the real hard boring work is done because we now know where TDC is.
So what you say? TDC is the starting point for all the readings we are going to do and remember the purpose of this exercise is to ACCURATELY measure some specifications.

The next question is why are you doing all this measuring in the first place?? If you have a stock engine with just minor mods like I/H/E and the car is running fine THERE IS NO NEED TO "DEGREE YOUR CAM".

Some engine builders like to degree a cam if you have purchased a new cam to make sure the new cam is installed to specs, or if you are going to be adjusting your cam timing which we will get to soon.


Measuring specifications


If you have all the stock parts installed on your block now is the time to see if the stock timing pointer and timing marks are accurate. Since we are at TDC it's a simple matter to look down and see where your stock pointer is pointing to. The stock pointer should be pointed directly at the TDC mark on your pulley or harmonic damper. If it is everything is GOOD. If it's not either you did a piss job setting up the degree wheel or your stock parts we not up to snuff from the factory (I would bet on the wheel not being installed properly).

Now that we are at TDC what the heck are we going to measure?? Well we came here to degree a camshaft but how the heck do you do that?

http://img.villagephotos.com/p/2005-12/1118998/camcard.jpg

This is called a "Cam Card" and all it shows are all the points where you can take precise measurements to see if your camshaft is installed correctly and is manufactured to the specifications provided by the manufacturer. It's not hard to figure out point "A" is the degree reading of how long the valve is open. Then look at point "B" that is the amount of lift that you should be getting. Point "D" tells you what to rocker arm ratio is (more on this later). Cam cards come with your new cam or the specifications are in the repair manuals of car manufactures.

OK but how do we go about measuring all that stuff use a ruler?? Nope we use the dial indicator like we used to check for TDC. But you need something to hold the indicator and keep it steady right??

http://img.villagephotos.com/p/2005-12/1118998/valve5.jpg

This complicated looking bad boy is really a nice setup using 3 dial indicators. One for each cam (DOHC) and the one in the middle to the top of the piston for finding TDC. It's nice but if you don't use one very often you can get away with just one dial indicator it's just going to take more time.

http://img.villagephotos.com/p/2005-12/1118998/valve7.jpg

This three indicator is kind of overkill for a SOHC. It's set up with the far right one measuring lift at the cam itself the center on at the tip of the rocker arm and one on the top of the valve. The one on the rocker arm is redundant as you will get the same result from the one on the valve spring.

http://img.villagephotos.com/p/2005-12/1118998/valve6.jpg

This one from the first setup shows it set up to measure at the top of the valve spring, you CAN do it this way BUT you have to remember to check and see what the ratio of your rocker arm or cam follower is. Because most rocker arms are not 1:1 they give more lift because they have a ratio of 1:1.65 so the end on the valve spring moves more than the end on the cam itself and you have to remember to figure in this added lift when doing your measurements.

So now that everything is set up all you do now is move the crank so the degree on the cam card is under your new pointer and then see..... Whoops you have to start at zero on the base (flat part with no bump) of the cam lobe. OK indicator is zeroed on base so NOW got to the degree from the cam card you want to measure and see if the amount of lift on the cam card matches the lift you are reading on your dial indicator.

If all the readings match you are in like Flynn and are done unless you want to adjust your cam timing. But if the readings don't match now you need to rotate the crank forward and back slowly to see if you have to retard or advance the cam to make the readings match.

Ok this is too long again so have to split it.............................

[claymore]

Checking valve to piston clearance

One thing I forgot to add is that while you have your indicator set up you can use this whole setup to check piston to valve clearance if you have the head installed on the engine. All you need extra is a soft spring about the size of a valve spring but not strong. A scrap master cylinder sometimes has a real nice one you can use. Take off the valve spring you are going to use and replace it with the soft spring. The soft spring is just to hold up the valve so it doesn't slide into the cylinder. Watching your degree wheel get to TDC. Set your indicator up reading zero resting on the top of the valve. Now gently push down on the valve until the head of the valve inside the engine touches to top of the piston look at the indicator and that is how much clearance you have. Let the valve back up and try it again a few degrees advanced then retarded off TDC and your done (if you have enough clearance).

A few of you have gotten all put off by the first part because it looks complicated. It IS time consuming but it's not that hard. If you had a ruler with little tiny marks on it and super human vision you could do it by hand. Old time engine builders can get TDC just by touching the top of the piston with his fingertips and rotating the piston up and down by hand. It just take practice and learning how to read a dial indicator.

Cam Timing

But now to the main event what a lot of members want to learn about. Remember this is just a GUIDE There are too many types of members cars to get it right on all your cars.

There are two reasons to even think about degreeing a cam and adjusting your cam timing.

The first reason is you have is because you bought a new camshaft and installed it and you want to make sure it matches the specs you ordered and is installed correctly. If it doesn't line up correctly with the stock timing marks you now can adjust it to the proper timing.

The second reason and what interests most members is to adjust the timing to "gain more power" or move the power curve up or down the timing scale.

I know we have discussed this before but it's a matter of physics that installing new adjustable timing gears "does NOT create more power. Yea I know several of you guys in the back of the room are jumping up and down ready to tell the story of your engine reading more KW on the dyno after adjusting the timing. That power is NOT created physically by the new pulleys being installed all that extra power is coming from the same engine using it's original form MORE EFFICIENTLY so the reading is higher but it's coming from the same engine just "TUNED BETTER" not from installing the gears and getting more power from the gears it's just a gear not a power enhancer. Think about this... you buy your nice shinny new adjustable cam gears and install them without doing anything else, what do you think more power or not??? Nope the increase in power comes from the better TUNE not the gears. I know it's semantics but we have to be accurate.

You guys are lucky that they now make adjustable cam gears in the "old days" we had to make our own advance or retard "things and one of the better ones was to make an offset key so the crank pulley could be physically moved clockwise (advanced) or counter clockwise (retard).

http://img.villagephotos.com/p/2006-1/1135975/key1.jpg

This is a homemade key and if you look at the side you can see it doesn't go straight up it is "Offset" and you put it in the key way with the step either left of right to advance or retard.

http://img.villagephotos.com/p/2006-1/1135975/key.jpg

In this photo it is installed on the left so in this case when you put the crank gear back on it would be twisted to the left making the timing retarded.

Not all the way back in the "Old days" we got lucky and speed parts manufactures started making gears with several different key ways milled in so you wouldn't have to do the work yourself.

http://img.villagephotos.com/p/2006-1/1135975/chain.jpg

Yea I know this is a V-8 timing chain set, just ignore the chain and look at the small pulley and notice all the different key ways around the inside of the gear and they even marked them for us. Using gears like this one could adjust the valve timing without degreeing the cam (if you felt lucky).

But enough history HONDA is why we are all here and this is it....

http://img.villagephotos.com/p/2006-1/1135975/gearbest.jpg

"B" series with adjustable gears installed.

http://img.villagephotos.com/p/2006-1/1135975/gear.jpg

WOW what a piece of machinery. The white marks scribed on the top edge of the gear are degree marks so you COULD move (adjust) the cams without a degree wheel.

I keep saying if you are lucky because you could take a chance and just move the timing without a degree wheel but it is more professional to use one and more accurate too.

http://img.villagephotos.com/p/2006-1/1135975/gear2.jpg

Another beauty and I would use this type over the HKS for one reason. If you look at the purple HKS it only has 3 bolts to keep the gear locked into the proper position while the silver one has five and some brands even six screws. If you think about the timing belt whipping around those pulleys at 9000 RPM you can be assured there is a BUNCH or torque being placed onto that outer surface of the pulley and all that is keeping it in place are those little bolts. So when you are thinking about buying a set find one you like with the most locking bolts.

Caution:

When you buy a new set of gears be sure to check the bolt that holds the gear to the cam. SOME BRANDS of gears are thicker than stock and the stock bolt MAY not screw into the cam far enough and MAY fall out causing major headaches. So physically screw in the bolt and make sure there are at least 4-5 threads caught by the bolt if not go and by a new bolt making sure the strength and specs of the new bolt match the old one only longer.

Be sure and READ the instructions that come with your cam or gears as the main bolt torque spec will probably be different than the stock bolt torque spec.

The second thing to remember is on some engines the clearance between the valves and the clearance from the valves to the top of the piston is very small and clearances CHANGE when you rotate the camshaft so either take your car to a knowledgeable tuner/engine builder or be darn sure to check with your cam manufacturer to find out if the changes you plan to make won't cause valve to valve or valve to piston clearance issues.

Before you start:

OK how do we know we need to adjust the cam timing?? We already covered installing a new cam and it is not in the proper position but what about in your car??

The procedure starts with buying a new cam. There are sooo many different things that effect getting the best cam for your application. Weight of your car, tires you are going to use, highest RPM reached, FD ratio,what HP you are going for, valve springs pressure, compression ratio, etc. etc. it goes on forever. The very best thing you can do it TALK to the guys at the manufactures of cams you may want to buy.

They hear the stories everyday and MOST will take the time to talk to you IF you have a list of your mods, type of car, weight, HP wanted all ready to go when you are talking to them. What they don't like is "tire kickers" calling around with no idea what so ever about their car and what you want to do so be prepared to answer their questions.

So you have your new cam installed but you are not quite happy with it's performance or with your stock cam for that matter what are your going to do?

There are two easy ways to change the characteristics of your cam. Advancing and retarding the cam can move the power band up or down a few hundred rpm. Advance for more bottom end and retard for more top end. It usually takes about a 4 degree change for a driver to feel it. The second way is to change the valve lash. Tightening the lash will increase the top end power while loosening it will increase bottom end power. You won't hurt anything by tightening the lash but check with your cam grinder as to the maximum lash you can use before running off the ramp and damaging the valves. When making these changes, increases at one end mean decreases at the other end.

Have to split this again.................................

[claymore]

Let's examine two scenarios for cars going to be used on a road course track. Car A is slow off the turns but has great power the last half of the straights. Loosening the valve lash or advancing the cam will increase power out of the turns with a slight power loss at top rpm.

Car B is slow off the turns but suffers from excessive wheel spin. The cure here is to kill a little power off the turns by tightening the lash or retarding the cam. This will enable the car to hook up better and cut lost power from wheel spin. Increased top end power will be an added bonus but the real need was to get horsepower off in the corners down to a level that the car and driver can handle.

Changing to a milder cam for car A or a larger cam in car B will accomplish the same thing but at a much higher cost in time as well as dollars.

One other important thing is knowing the minimum rpm encountered. Few drivers can accurately tell you what their lowest rpm really is. It is hard to be fast if your cam has a power range of 4500 to 7000 and your restarts are 3500. The lowest rpm encountered is as important as the maximum when selecting the proper cam.

The same thing for a drag racing car. If you are getting shitty 60 ft times with hardly any wheel spin or even bog but doing great on the top end you could adjust the cam timing to advance the timing and get more usable power on the bottom end to help with your 60 ft times.

If you have a real light weight car and wheel spin off the line is killing your 60 ft times you could retard the cam timing to kill some bottom end and better control the wheel spin while getting better on the top end.

Adjusting the cam position:

Yea yea I know everybody likes this stuff but some people want to get to the question HOW DO YOU DO IT??

Again it's VERY SIMPLE all you are going to do is physically turn either the gear or the camshaft until they are advanced or retarded to the point you want them to be. Simple to talk about but time consuming in practice.

Unless you are just messing around changing the position just for the fun of it you need a plan. I mean how the heck do you know how much to advance or retard???

This is where it gets down to the nitty gritty. Probably the best answer to start out with is do you have a baseline reading for you car before any cam timing changes??

You should make a few runs around your favorite road course or a few times down the strip and RECORD that information like times for 60 ft, lap times, split lap time weather, temperature, etc or make the trip to your local dyno and make some pulls. Now you have a starting point and will know if the changes you make are helping or hurting your performance.

Now for our members with more limited budgets. You CAN make changes without going to a dyno but it will take considerably more time to determine if you are getting results because you have to go to the track or strip and make some runs to see what is happening with your times.

Doing the changes on a dyno where you can make a pull then change the cam timing and see the results instantly is a great time saver if you can afford it but remember SOMETIMES great results on the dyno don't necessarily mean better times on the track because the dyno can't measure for other factors like tires, car weight, suspension etc. And using a dyno you need a tuner who can interpret the results to see if the power curve is heading where you want it not just making more total power.

Now that you have your spiffy new gears and you plan on making changes there is one mod that will help you save loads of time.

http://img.villagephotos.com/p/2006-1/1135975/gear1.jpg

Sorry it's not a Honda engine but you get the idea. Cutting out a portion of the cam drive belt cover so you can get to the adjustment bolts, and the main cam gear bolt will allow you to get at these parts so you can adjust the cam timing without having to remove the cover every time.

Now that you have decided to change the cam timing what do you do?

Just look at you new cam gear and note the lines scribed into it while you have the engine at TDC, no you don't have to go through all THAT again remember you checked the stock timing pointer while we were finding TDC and it's accurate right??? Now you can use the accurate stock pointer and marks on the drive pulley just like you were setting ignition timing.

Make very sure in your mind to read the degree marks correctly and you are turning in the proper direction you want, advanced or retard (most good gears have directional marks or indications on them).

If you have the engine out and everything is exposed you can go at it in two ways.

http://img.villagephotos.com/p/2006-1/1135975/gearbest.jpg

One way is to get everything lined up like you were changing the belt and with everything open like this it's a breeze. Then after loosening up the belt tensioner loosen the adjustment bolts a bit while it's easier, then just take out the main bolt and take the gears off the engine. Put the pulleys on a bench and move the lines until they are lined up with the amount of advance or retard you want and tighten down the adjustment screws. Then just put the pulleys back on like you had replaced the belt.

The other way is if the engine is still in the car and all together. If you haven't cut your cover you have to take the cover off to gain access to the gears and then you have to loosen the adjustment bolts and main gear bolt and then the fun starts because you have to move the cam in the proper direction and end up with the proper advanced or retarded mark lined up on the pulley. Once it's all lined up don't forget to re-tighten the adjustment bolts and the main bolt using the torque specs on the cam or gear instructions.

Since there are a bunch of different type of engines and cars out there I will leave it up to you how you rotate your cams or cam to get the lines lined up.

That's all I have for now once you make your changes it's either off to the track or Dyno to test your car and see the results but now that you are an expert if you don't like the results you can do it all over ag