reading over some of the comments and i cant seem to grasp why a few people can not seem to understand this method or question it? watching over it a few times has helped me understand and worked fine on rebuilding my mini engine, many thanks to the MiniMania team!
I wish I can grasp this at first hand . I do understand that in this stag of the build is the most important part of any build and the most part hard to grasp but if you buy instruction and the steps then it's easy know matter if you understand it or not . The thing is that it helps to understand it and the reasoning of it . I my self would think not understanding and follow instruction than to do it what i think is right way of doing it right because i would be completely wrong . Thanks Mini Mania for the lesson .
i was watching this thinking i could totally build a classic mini engine, ti this point. haha, I'm sure watching it a few more times will help me understand.
Our 40+ years of engine building trumps your theory. This is a tried and true method for setting the cam timing on a A Series engine - and the proof is in the pudding. This engine ran beautifully on the test stand (as all of our engines do!). We'll leave it at that.
I would urge anyone watching to also look carefully at positive stop or split degree methods of cam timing. "Judging" TDC may work on some engines when combined with experience but it will not always be the case!
no piston stop? maybe run the dial to .050" before max indicator value and reference the degree wheel, then continue through tdc to the after max dial value .050" mark and re-reference the degree wheel. find the median of two points and move the crank to that mark, then spin the degree wheel so zero is at that location. then verify the move is on point? properly setting the degree wheel is important especially if aftermarket cam is used. a few * off can cause undesired running conditions.
Let me see if I understand it right: you did the first assembly and testing to figure out what offset you need on cam gear because you have an aftermarket cam? As in the first time you assembled and got the numbers would have been proper for a stock cam?
When you rotate the crank 25º then back to 5º is that because you need a 5º key? Or is it just a general rule? i.e if you needed a 7º key would you move it 25º then back to 7º. Thanks.
To clarify, was the 107 target number from the cam spec sheet or is that some "magical A series tuning number? Why was that the number you were looking for? Thanks for the great video. More please!
The 107 number refers to the recommended number of degrees past TDC for this particular cam. The cam in question is our performance street cam part no. CAM103M.
@@minimania Mini Mania So, after watching this and th-cam.com/video/mPdSCWZbHEU/w-d-xo.html I can see that your method of measuring and adjusting was aiming for maximum valve lift at 107° past TDC. And that would give a crossover point for inlet and outlet valves which is appropriate for your cam shaft. Think I'm with you so far. I just wanted to point out that most dial test indicators don't display degrees, so when you were measuring "5°" either side of maximum travel on the push rod, would you have actually been measuring 5 thou of an inch? The cam shaft and timing chain then translated that vertical movement to a rotational movement that you could read from the blue timing wheel? Therefore, the only reason for fitting the offset key that I can see is to account for your non-stock cam shaft. And if we were to measure the angular difference between maximum lift on the inlet and exhaust push rods we could determine the overlap position after TDC?
Lobe center at 110°? This video demonstrates for a 107°. At any rate, follow the procedure in video - make sure to set up TDC carefully - then use the second hole from the front for the first intake valve and insert the push rod. Set you dial indicator on the push rod and zero it to maximum intake lift - then go counterclockwise (from the rear of the engine) first to 25 then back to 5 - take the reading from the dial on the front of the engine. Do the same thing clockwise (again from the the rear of the engine) - to 25 and back to 5 and take that reading from the dial on the front of the engine. The difference in two numbers is where you are. If you get say, 112°, then you need a 2° offset key for a 110° cam - make sense?
It makes sense and we must have watched this video about 100 times while doing what you have explained but only get small numbers to add, like 11 and 7. The only thing we can think of is our dial is different but even that doesn’t make sense cause looking at your movement and ours they would be the same.
Notice also that when Tony is counting in the video he's starting @ 90 the first time and counting up - not down - on the dial indicator even though technically the numbers are going down on the dial. Maybe this is where you're going wrong?
Your lobe center would actually be 105deg. if you had true TDC to start with. 122-92 / by 2 +90=105 or another way you can go is 122-92 +180/by2=105. The way your doing it is adding the opening and closing figure without the rest of the duration and dividing it by 2 and calling that your LC. .006 is not the best number to start checking the timing numbers from. the standard of the industry is .020 or .050.
unfortunately you made mistakes right from the start. You must find TDC with a piston stop or stop the piston before TDC at a certain point BTDC . Then split the amount for true TDC, then in setting the cam you must subtract the small number from the large number divide by 2 and add 90deg to get your cam lobe centre. IE. if it's the intake valve you must subtract the opening number from the closing number divide by 2 and add 1/2 of the rest of the duration , which is 90deg., to get your LC.
![Operation Bad Wolf [Ep 13] - How to Set your Cam Timing/Advance | Classic Mini](/img/n.gif)
reading over some of the comments and i cant seem to grasp why a few people can not seem to understand this method or question it? watching over it a few times has helped me understand and worked fine on rebuilding my mini engine, many thanks to the MiniMania team!
I wish I can grasp this at first hand . I do understand that in this stag of the build is the most important part of any build and the most part hard to grasp but if you buy instruction and the steps then it's easy know matter if you understand it or not . The thing is that it helps to understand it and the reasoning of it . I my self would think not understanding and follow instruction than to do it what i think is right way of doing it right because i would be completely wrong . Thanks Mini Mania for the lesson .
Kk
Great video! Nice to see the theory put into practice in a clear concise way :) Thanks @minimania
i was watching this thinking i could totally build a classic mini engine, ti this point. haha, I'm sure watching it a few more times will help me understand.
This is a great video. I used this procedure, and it worked for me. Many thanks!
Our 40+ years of engine building trumps your theory. This is a tried and true method for setting the cam timing on a A Series engine - and the proof is in the pudding. This engine ran beautifully on the test stand (as all of our engines do!). We'll leave it at that.
Our method of calculating TDC is just fine for our purposes, thanks.
I would urge anyone watching to also look carefully at positive stop or split degree methods of cam timing. "Judging" TDC may work on some engines when combined with experience but it will not always be the case!
no piston stop? maybe run the dial to .050" before max indicator value and reference the degree wheel, then continue through tdc to the after max dial value .050" mark and re-reference the degree wheel. find the median of two points and move the crank to that mark, then spin the degree wheel so zero is at that location. then verify the move is on point? properly setting the degree wheel is important especially if aftermarket cam is used. a few * off can cause undesired running conditions.
You're absolutely right, nice catch, he did it incorrectly because he didn't factor in dwell.
Very good video. I have a 270 / 106 camshaft on A+ 1275, hif44, lcb, ported head. do i need an offset key ?
see the annotation starting at 4:12 in the video - it explains it.
Tony you are a great teacher! Cheers mate!
Let me see if I understand it right: you did the first assembly and testing to figure out what offset you need on cam gear because you have an aftermarket cam? As in the first time you assembled and got the numbers would have been proper for a stock cam?
When you rotate the crank 25º then back to 5º is that because you need a 5º key? Or is it just a general rule? i.e if you needed a 7º key would you move it 25º then back to 7º. Thanks.
No, this is simply to take the "slop" out of the chain - especially if the chain isn't being replaced with you're doing the timing.
To clarify, was the 107 target number from the cam spec sheet or is that some "magical A series tuning number? Why was that the number you were looking for?
Thanks for the great video. More please!
The 107 number refers to the recommended number of degrees past TDC for this particular cam. The cam in question is our performance street cam part no. CAM103M.
@@minimania Mini Mania So, after watching this and th-cam.com/video/mPdSCWZbHEU/w-d-xo.html I can see that your method of measuring and adjusting was aiming for maximum valve lift at 107° past TDC. And that would give a crossover point for inlet and outlet valves which is appropriate for your cam shaft. Think I'm with you so far. I just wanted to point out that most dial test indicators don't display degrees, so when you were measuring "5°" either side of maximum travel on the push rod, would you have actually been measuring 5 thou of an inch? The cam shaft and timing chain then translated that vertical movement to a rotational movement that you could read from the blue timing wheel? Therefore, the only reason for fitting the offset key that I can see is to account for your non-stock cam shaft. And if we were to measure the angular difference between maximum lift on the inlet and exhaust push rods we could determine the overlap position after TDC?
Hi there we are trying to do as you but are only getting small numbers to add together, what are we doing wrong. We are using a 731 cam in a 1275.
Lobe center at 110°? This video demonstrates for a 107°. At any rate, follow the procedure in video - make sure to set up TDC carefully - then use the second hole from the front for the first intake valve and insert the push rod. Set you dial indicator on the push rod and zero it to maximum intake lift - then go counterclockwise (from the rear of the engine) first to 25 then back to 5 - take the reading from the dial on the front of the engine. Do the same thing clockwise (again from the the rear of the engine) - to 25 and back to 5 and take that reading from the dial on the front of the engine. The difference in two numbers is where you are. If you get say, 112°, then you need a 2° offset key for a 110° cam - make sense?
It makes sense and we must have watched this video about 100 times while doing what you have explained but only get small numbers to add, like 11 and 7. The only thing we can think of is our dial is different but even that doesn’t make sense cause looking at your movement and ours they would be the same.
Notice also that when Tony is counting in the video he's starting @ 90 the first time and counting up - not down - on the dial indicator even though technically the numbers are going down on the dial. Maybe this is where you're going wrong?
Got it sorted thanks for your help, we were turning the dial back to Tdc after getting the valve up to maximum lift.
Sir my dial gauge is mm how to do? Think you
Your lobe center would actually be 105deg. if you had true TDC to start with. 122-92 / by 2 +90=105 or another way you can go is 122-92 +180/by2=105. The way your doing it is adding the opening and closing figure without the rest of the duration and dividing it by 2 and calling that your LC. .006 is not the best number to start checking the timing numbers from. the standard of the industry is .020 or .050.
Think Il need to watch this one a few times. Shame about the tool to table noise lol.
unfortunately you made mistakes right from the start. You must find TDC with a piston stop or stop the piston before TDC at a certain point BTDC . Then split the amount for true TDC, then in setting the cam you must subtract the small number from the large number divide by 2 and add 90deg to get your cam lobe centre. IE. if it's the intake valve you must subtract the opening number from the closing number divide by 2 and add 1/2 of the rest of the duration , which is 90deg., to get your LC.
made perfect sense to me...cam card called for 107
Mini cuper
Potentially very interesting vid, but terrible camera work, moving around all the time, & I'm not even drunk.
once I see pliers on a dti I just move on , this butcher should be slicing bacon not building engines , its that simple.
Could have been explain more clearly! How do you expect people to understand that.
see the annotation starting at 4:12 in the video - it explains it.