1150 cams in a 1100

[Fjbj40]

I found this helps slot if you are trying to precise.
http://www.thegsresources.com/_forum...t=Degree+wheel

I read that one, I need to get a better wheel than I currently have. I made one myself from an online printed sheet and piece of aluminum.

[posplayr]

I read that one, I need to get a better wheel than I currently have. I made one myself from an online printed sheet and piece of aluminum.

With 600 dpi print resolution, I suspect that if the wheel was at least flat and centered you are fine. I insuring proper perspective of teh needle to wheel alignment will probably add much more variability.

My finding was that with the back and forth measurement of one side and then the other of TDC, with a precise reading of the wheel, you developm much more confidence in the measurement and can iterate to the final degree settings much faster.

Sighting down the edge of the razor just takes a lot of variables out of the measurement and therefore improving repeatability (I'll not repeat my analysis here). It is hard to imagine anybody arguing the point, but then again I have to realize there are plenty of people that are insecure enough that they will argue against the most basic principles in defense of their prior practices regardless of what "new" might come along.

No reference to you but rather the parties in the other thread, I just revisited.

[Fjbj40]

With 600 dpi print resolution, I suspect that if the wheel was at least flat and centered you are fine. I insuring proper perspective of teh needle to wheel alignment will probably add much more variability.

My finding was that with the back and forth measurement of one side and then the other of TDC, with a precise reading of the wheel, you developm much more confidence in the measurement and can iterate to the final degree settings much faster.

Sighting down the edge of the razor just takes a lot of variables out of the measurement and therefore improving repeatability (I'll not repeat my analysis here). It is hard to imagine anybody arguing the point, but then again I have to realize there are plenty of people that are insecure enough that they will argue against the most basic principles in defense of their prior practices regardless of what "new" might come along.

No reference to you but rather the parties in the other thread, I just revisited.

It was a rather interesting read

My wheel was okay and up to the job. What I did was make the pointer the width of the degree gaps and the wheel was flat enough that the pointer was only about .040" off the surface.

This made it easy to get the readings, actually quite easy.

The only issue was I ended up getting the numbers I wanted but when I looked at the notches on the cams there was a large spread! So I rechecked true TDC and sure enough the wheel moved, this was after Loktite. So I had to redo it.

I am sure I seated the new rings into the cylinders though

Cheers

[posplayr]

It was a rather interesting read

My wheel was okay and up to the job. What I did was make the pointer the width of the degree gaps and the wheel was flat enough that the pointer was only about .040" off the surface.

This made it easy to get the readings, actually quite easy.

The only issue was I ended up getting the numbers I wanted but when I looked at the notches on the cams there was a large spread! So I rechecked true TDC and sure enough the wheel moved, this was after Loktite. So I had to redo it.

I am sure I seated the new rings into the cylinders though

Cheers

As I described in the thread, my motivation was the readout accuracy I saw at RapidRay's shop. He was degreeing my engine using his big wheel and had me read off the angles. Then he leaned over and read a number himself and promptly told me I was reading 1 degree off. It became obvious that where you stand can make a huge difference (i.e. 1 deg ) even with the big wheel.

Another subtle factor is that when you measure two angles on each side of TDC and then diffence them, teh error goes up (statistically) by 1.41 again.

So if you figure 1 degree variation for the 18" wheel, that equates to 2 degree error for an 8" wheel and the error you used to move the cam is 1.41 times that or close to a full 3 degree of potential error (+ or - 2 sigma).

It is no wonder that you might have to go through multiple iterations of back and forth (which I experienced as well) measurements trying to figure out where a cam lobe really is if you have such sloppy tolerances.

With the razor I figure it was easy to get to 0.1 deg (1 sigma) and so there was a lot less trial and error getting to the proper settings. Perhaps as an engineer I'm much more aware of these things as it is part of my practiced skill set. Ironically this turned out to be even more controversial than the wheel alignment techniques debates. (the string v.s .the laser).

If you are careful about how you read a piece of wire (or can keep a sharp point next to a flat disk), you can do a reasonable job I suppose. If you have significant distance or less than fine point on the wire, there is really no way to know how accurate you really are as just moving your head a little can make a pretty big difference.

[Fjbj40]

I totally understand what you are saying. I strive for perfection, within limitations, on everything I do. I am an aircraft mechanic by trade, I accept nothing but the highest level of success in my job.

The pointer I used is exactly the same width of the degree markings, if you are not looking at it perfectly straight when you take the reading you will see the side of the pointer and not just the front, so you know you are not reading it correctly. Looking straight on you will just see the front and no sides of the pointer, make sense?

For me, it was the best that could be done at the present time. I am sure I will improve my technique on the next one, I will look over your thread again and see how I can use it to improve, multiple ideas are always better than just one idea as long as they are looked at in an unbiased manner.

[posplayr]

I totally understand what you are saying. I strive for perfection, within limitations, on everything I do. I am an aircraft mechanic by trade, I accept nothing but the highest level of success in my job.

The pointer I used is exactly the same width of the degree markings, if you are not looking at it perfectly straight when you take the reading you will see the side of the pointer and not just the front, so you know you are not reading it correctly. Looking straight on you will just see the front and no sides of the pointer, make sense?

For me, it was the best that could be done at the present time. I am sure I will improve my technique on the next one, I will look over your thread again and see how I can use it to improve, multiple ideas are always better than just one idea as long as they are looked at in an unbiased manner.

Sighting down the wire is the key. The old pros probably just take for granted but anybody doing this for the first time would not realize .

[oldgsgkd]

cam makers have said up to 4 degrees before noticing a noticeable change

[posplayr]

cam makers have said up to 4 degrees before noticing a noticeable change

If you are going 110/110 you probably don't want to mistakenly go 114/114.

Stock motors probably have +/- 4 degrees of slope (2 degree 1 sigma)

Back in 1980-81 they also have noticeable 1/4 mile ET's on 1100E's due to manufacturing tolerances on valve jobs.