Tag Archives: flywheel

A12GX Head – A14 Sub – Dual SU's – Lightened Flywheel

What a busy few weeks getting the Bakkie in order.

Just want to give all that provided me with tips and tricks some feedback.
Got the Datsun

Comps spec on the flywheel, took the flywheel and a new pressure plate to the dude that does my machining, he got it down to 5.78kg, he also balanced the flywheel and new pressure plate for me.
Installed the A12GX head with worked ports and valves.
Fitted a 4-1 branch manifold, already had a 50mm Stainless Free flow System
HS4 Dual SU Carburetors, intake manifold ports matched to head intake ports
Fitted a electric fan, switch comes on at 85degrees, removed mechanical fan on water pump
Had to purchase a new Temp Sensor, could not get the old one out of the A14 head.

Here comes the interesting bit, somewhere down the line, they changed the resistance on these sensors, from about 560ohm to about 360ohm at 16degrees.
This caused more than enough problems. All of a sudden the temp gauge needle climbed way more that it should.

We started it up, all was fine, no bolts, pistons or valves flew around, tuned the su’s. The electronic fan came on, everything working as it should.

Once on the road it was a different story, torque there is a lot of, it is clean, revs up nicely, pulls excellent from 2k rpm right thru to the limiter (currently at 7k rpm), there is not even signs that you are about to hit the limiter, this means all is working together, producing nice bottom down torque and decent top end power.

Then, all of a sudden the motor gets hot. After a day or two and enough swear words to make a sailor look like a beginner. We figured it out. Once on the road there is enough air travelling over the switch to cool it down and not switch the fan on. This caused me more time under the bonnet than needed.

Obviously if the water gets way to hot, pressure builds

and want to escape somewhere, the place it picked was between cylinder 3 and 4 at the water ports on the intake manifold gasket. After taking it apart, I also noticed that the one exhaust manifold washer was pressing against a piece of welding on the branch. Smoothed it down, reassembled the lot. Also re-fitted the old mechanical fan on the water pump to be on the safe side.

Took it for a drive, no issues what so ever anymore, the fan doesn’t even switch on after some heavy spinning and gymkhana practice.

Saturday we have our next race meeting and look forward to the added power and overall better A14-A12 inbreed.
Just hope I will be able to keep the wheel spin to a minimum, we are expecting rain also, and that sure as hell wil not help.

Thanks a lot to all that helped and gave advice. Special thanks to Einstein(My Brother), My Father and Ruan.

Datsun is treated to a lightened Flywheel and bigger Clutch

cialis online purchase

p?g2_view=core.DownloadItem&g2_itemId=557&g2_GALLERYSID=TMP_SESSION_ID_DI_NOISSES_PMT” alt=”LFlyFront” width=”384″ height=”288″ />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

Component Weight
A12 9.0kg
A14 11.5kg
A12 Lightened 5.78kg
Old 180mm A-Series Pressure Plate 3.1kg
New 190mm A-Series Pressure Plate 3.1kg
Old 180mm A-Series Clutch 0.8kg
New 190mm A-Series Clutch 0.825kg
New Flywheel, Pressure Plate & Clutch 9.0kg

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.