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Mini Vernier adjustbale duplex timing gear set

Mini Vernier adjustbale duplex timing gear set

Mini Vernier adjustbale duplex timing gear set
Part No: C-AJJ3327
Fits the following:
Classic Mini
Sprite & MG Midget
Morris Minor
Alternate Products
Classic Austin Mini duplex chain gear kit cam drive lightweight
$169.95 Classic Austin Mini duplex chain gear kit cam drive lightweight
Adjustable cam gear set. Even a stock camshaft needs to be timed correctly. If you want to get the maximum benefit from a "hot" cam it is doubly important that the cam timing be correct. This adjustable timing gear set uses sets of dowel holes with two degree increments. When done properly your cam will be within one degree of right. (Use a 1 degree offset key and you can be exact!) Kit includes billet steel upper and lower gears plus a quality chain. See AEA687 for new counter-sunk screws)
Fitment of an uprated cam drive system is essential when building a performance oriented engine. Timing scatter induced by the standard set up can reach up to 15degrees once the single row chain has stretched, which it does after only a few miles. This scatter not only affects the cam timing, but also the ignition, the distributor being driven by the camshaft. Power loss suffered by this phenomenon is substantial. Replacing the standard single row (simplex) system with a dual row (duplex) system greatly reduces the problem, use of a toothed belt system all but eliminates it. The belt system vastly reduces valve train noise and also helps damp out some of the odd harmonics generated by the 3 main bearing 'A' series engine. It is also extremely important to time any cam in to it's required setting to obtain maximum performance, especially with performance cams. The 'dot to dot' method can, because of manufacturing tolerances, be out by as much as 15degrees. Anything above 2degrees out and power suffers-most noticeably in small bore engines. In race engines you probably lose 1 hp for every degree the cam is out, more when over 6degrees! Technical Note:

PART NUMBER                            DESCRIPTION                             QUANTITY

C-AEG578                                     Camshaft sprocket, lightened          1
AEA695                                        Crankshaft sprocket                               1
2H4905                                        Timing chain                                             1
AEA687                                        Screw - countersunk                              2

The front plate will have to be countersunk as shown ‘X’ to take the screws AEA687, which replace the existing hexagon-headed screws, which would foul on the timing chain. Check for clearance on chain all round and align gears as per Workshop Manual.

When using ‘A’ plus timing covers there is a small round pressing at the bottom which needs making flat to allow timing chain clearance.

Ensure that the crankshaft oil thrower 12A1148 is correctly fitted with the letter F. Facing you or on very early engines the lip faces outwards.

Related Technical Articles:
Classic Mini Cooper Camshaft drive kits page 39
Created: January 10, 2019
Camshaft to engine timing drive kits, single row chain, double row chains and belt drive kits are all options for the Classic Mini Cooper. Upgrade and high performance duplex chain kits with adjustable timing gears are also an option.
Timing Chain Replacement for A-Series engines
Created: February 28, 2018
Building an engine is very much like most things in life- the more attention to detail you give an effort the more likely you will get the results you were looking for. Whether you are installing a new stock or performance camshaft or even simply rebuilding your motor with the stock camshaft getting the valve timing correct is one of the more important things that you can do.