I just set it dot to dot with a duplex chain. I have used the 544 cam very successfully in a number of engines - without the hassle of fiddling with offset keys etc. What works well in one engine may be hopeless in yours. There is no way of knowing exactly what will be the 'best' timing for a cam like that in YOUR engine. Most people make an additional 1-2 degree offset to the cam timing to compensate for timing chain stretch that will occur during the break in period of the new timing chain. Knowing the angular error, you select an offset key to provide the correction OR you use the vernier pulleys to create the correction. Regardless, the method of setting the cam angle is to measure the cam angle as installed before any adjustments/corrections are made (requires dial indicator and degree wheel) then determine how many degrees out the cam is from ideal. If you can't find those old threads, post back and we'll help locate a few. Please try the search feature to find a few of these threads and read up on the process.
#Mini cam timing how to#
There have been several threads here (with external links to tech articles) that describe how to degree a cam. Setting the cam angle using any method other than dot-to-dot dictates that you MUST have a dial indicator and degree wheel.
You do not choose the offset key based on the cam maker's specs, you choose the key based on careful measurements. To set this angle accurately you use EITHER an offset key with standard timing pulleys, OR you use the vernier adjustable timing pulleys. This however will not set your cam to the grinder's specified optimum angle. The cheapest is to use stock timing pulleys and line them up using the dot-to-dot method described in the manual. But I do have comments on the offset keys. No comment on the cam selection and or other go-fast bits. The 286 is a really lumpy cam and as you will be using lots of revs all the time to keep it on-the-cam expect to rebuild the engine more often. Of course, you can simply set the cam using the standard dot-to-dot method and it will run, but if fitting a 286 you won't get best power and it could run even worse at low revs that it will do when timed in accurately. You may have to mneasure and re-set several times to get it absolutely right which is essential in a race engine. You measure using a DTI and crank protractor to measure the basic setting without any adjustment, then fit the offset key or rotate the vernier sprocket to remove any error. To achieve this accurately you need to use either an offset woodruff key or a vernier cam drive sprocket.
With regard to timing, the ideal timing for a 286 is 106 degrees ATDC on inlets. also, with a 286 your engine should be capable of revving safely to about 6800 rpm and a final drive low enough to allow you to pull away without excessive clutch slipping in 1st. Without all this you'll just get all the disadvantages of the 286 with none of the advantages. It also needs a well gas-flowed head, twin 1.5" SU carbs (or something equally good), a good exhaust system, a lightened flywheel, etc. Whew, that only took me 5 hours to figure out.The 286 is a race/rally cam and as such it is not really very good for a road-going Mini which is not going to be used in serious competition. Rotate crank each direction Take readings 5 degrees on either side of maximum valve lift.ĭegree wheel read 110 degrees and 95 degrees.Īdd numbers together 205 then divide by 2 = timing at 102.5 degrees. Rotate crank forward until pushrod lift is at maximum. Place camshaft timing degree wheel on crankshaft end, mark 0 or TDC. Insert pushrod in second valve and place dial gauge on it. I've heard of a few degrees separation but is 25 degrees ok? However when I did the below timing method it shows that my dots are 25 degrees apart. When installing the timing gears you would normally align the dots on the timing chain gears to each other and then fine tune them. The Kent camshaft should be advanced 3-4 degrees, so I should be setting the timing to equal 103 degrees. It is my understanding that the timing for the cam on a standard mini engine is at 106-107 degrees. Installing duplex double timing chain and a Kent 276 Megadyne Cam in 1293 A+
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