Datsun is treated to a lightened Flywheel and bigger Clutch

Last week I found an old Datsun A12 flywheel in my garage that my brother used a few years ago on A12 and A14 motors. This particular flywheel was lightened a bit, but the two of us thought that as the years went by, we can greatly improve what was done to it previously. In a moment of superior thought, I remembered I have a few pictures of lightened flywheels from  “Datsun B110 Competition Tune-Up Manual, Nissan Motor Co. Ltd., Tokyo Japan 1974″ that I have sourced from http://datsun1200.com site.

And so it began. I sourced a 190mm LUK clutch kit (had an idea the current clutch is only 180mm), found a a guy that does machining and dynamic balancing, made a appointment with him. I showed and explained the drawing to him, the next day I picked the super light flywheel up and was very pleased with the end results.

Here is a table comparison of the A12, A14 and Lightened A12 Flywheels

On dissembling, my thoughts where cast in stone, indeed the old clutch and pressure plate was only 180mm units. This meant that the clutch and pressure plate was still the original units. I need to give credit for Datsun, wow, that says a lot for quality.

After the gearbox was put back in it’s place and all the other nuts and bolts tightened up, my father and realized there was no clutch. And then it hit us, the A12 flywheel is much thinner than the A14 unit. This meant that the release bearing was unable to travel enough to get to the fingers on the pressure plate. This meant double work, one thing that really ticks me off. Work started dissembling everything again. After some serious measurements, we decided to increase the length of the pivot point that the fork pushes against. The original unit was replaced with a alancap with a shank and a nut to lock it in place, added some locktight and it is in place to stay.

Assembly started again, after all was done, clutch was good and we just double checked everything to make sure that the release bearing retainer does not move off, of the slide if the clutch is operated, that could lead to a locked clutch. Almost like trying to drive with the gearbox in neutral. What a lot of fun this could be.

Have a look at the pictures of the old and new Flywheels.

Datsun A12GX Head & Dual SU Carb Project Started

Last weekend, after my official duties at the Toyota Dealership Rally out in Caledon where finished, I decided to drive to my parents in Doornrivier for a visit and to get my little hands on some old Datsun parts.

One of the best decisions in a long time. It took me back a few years when my brother used to tinker with these little motors. These parts is almost like family treasures, as a lot of it came from my dad that also used to play with Datsun engines.

The idea of this project is to get these parts all cleaned up, assembled and installed on the bakkie, if memory serves correct there will be no need for mayor structural changes to the parts as A12-A14 engines are very interchangeable. The head was first on a A12 and later on a A14 that seized two pistons due to,  to much compression and running on normal 97 octane fuel (back in the day of 97 octane in SA).

The motor where rebuild and a spacer where added between the bottom end and head to drop the compression enough. This engine had a lot of torque and also very responsive.

The Head:

• A12 GX Head
• A14 Intake and Exhaust Valves
• 3 Angle Valve Seats
• Double Valve Springs
• Ported

The Carbs:

• Dual SU something something carbs ( will get numbers )
• Ported Intake to match the Head
• Custom Air Filter Housing

Johan (friend) started yesterday stripping the parts and the huge cleanup process. To my amazement the valves came out much easier than expected. I thought these double valve springs are going to require some serious fore arm strength, a knock with a hammer on the valve spring retainer was all that where needed, but still far more difficult than a head with only one set of valve springs.

Later on Ruan joined me, we had a long discussion around the SU carbs as they are fairly new to him, my knowledge on them is also quiet limited, thus it took some time explaining the operation of these carburetors. For more information regarding SU Carburetors, visit Wikipedia

The idea is to get all planned and assembled before 2 May 2009, after the 2nd May we want to start bolting these beauties to the bakkie, in the whole process I also want to swop the flywheel out for one that is  lightened and replace the stock clutch and pressure plate with a Datsun Pulsar unit, these are larger and still just a bolt on.  The other modifications that will be done at the same time is the fitment of a electric fan and a 4 into 1 branch exhaust manifold.