Lotus Elan and Lotus Elan Plus 2 Forums

Bud, you have a PM.

Well, even though we can't buy many of the vehicles the rest of the world can because of the influence of big insurance we can still modify cars. Building one from scratch??? That is another topic....

Kurt

Thanks for the responses re dvla. I think Andy is spot on with his post. It may be that using the likes of Spydercars to do the conversion and sign it off is the way to go.

Sean.

E-bay shows a Zetec cast flywheel and clutch kit for cheeeep money. Don't know what would be required for ring gear or TO bearing.

Kurt

A good sized lathe and the Rob Walker (prezoom), purpose built, flywheel holding hub which I have in my possession and can pass on with his blessing. You'll need it to machine the flywheel to the proper diameter to accept the correct ring gear and mate up with your starter.

Machining the flywheel for the 110 tooth ring gear was the most tedious thing I think I have ever done. I contacted several automotive machine shops in the area to have them make the modifications, only to be told they wouldn't touch it with a 10' pole. I consider myself a metal remover, not a machinist, but the work had to be done. I have a 13" lathe, and it is not realistically big enough to perform the task at hand. The compound will not move back far enough to clear the outside edge of the flywheel. As I had mounted the flywheel to the chuck in the orientation as it was mounted on the crankshaft, all the machining was done from the backside. To do this, I had to weld up a brazed carbide cutting tool to a home grown adapter that when attached to the tool post holder, would reach around the back of the flywheel. With the cutting edge of the tool so far from the holder, I didn't trust the assembled cutting tool to accurately cut what was dialed into the lathe. I was also concerned with the tool digging into the flywheel. So, I took very small, .002", cuts to get to the final dimension. I took the better part of a day and into the evening to complete the task. Even refused my wife's call to eat diner, as I didn't want to stop until I finished. The end result was far better than I expected. Prior to the machining, I had mounted the flywheel to the crankshaft to measure the runout in two axis. The result was .0005". After the machining process, I remounted the flywheel to the crank, measured again, and the result was the same as before machining. The sigh of relief could have been heard around the world.

Rob, how much material had to come off?

Greg/Rob,

I am not sure about this, but if your flywheel came with 135 tooth ring gear, then a 10 tooth pinion on your starter should engage with the ring gear.

Hope this helps,

Richard Hawkins

The 135 tooth ring gear from the Fidanza flywheel was larger in diameter than the one on a steel flywheel from TC. I don't remember the exact number, and I ditched the old one. To get a new diameter for the 110 tooth, I removed the knackered one from the steel flywheel and measured the flywheel outer diameter. I then measured the inner diameter of my new ring gear from Bean, to determine the interference fit. If memory serves me, it was .020". From Beans catalog I took the maximum temperature one should heat the new ring gear, but decided I would try a lower temp, 450 degrees F. Used a MAAP gas torch to heat the ring gear hanging from a wire hook. When it reached the desired temp, I used two pliers on the ring gear and dropped it onto the aluminum flywheel, with no additional assistance. The original Fidanza unit had three 10-32 button head cap screws equally spaced around the flywheel between the ring gear and the flywheel itself to help prevent any rotation of the ring gear. I could not use the old locations because the threaded holes were mostly removed in the machining process. I indexed three new holes equally between the old holes. I did this on my mill, using a rotary table. Everything is still holding together, so believe the solution was workable. The main difference between the steel flywheel in my S2 and. the Plus2 is, the Plus2 revs much quicker and less throttle is required to get things spinning.

Thanks for the info, guys. I'm currently recovering from a round of the Covid, just in time for Christmas!

Kurt

So, Rob, you have Zetecs in both the S2 and the Plus 2?

I would think that in my S1 with the close ratio box and anticipated 3.5 diff that a heavier flywheel would be preferred to hopefully help in getting the car started from a stop. I now have a 3.7 on the twin cam and have to pay attention when getting underway. Of course the Zetec is going to have considerably more torque.

Kurt

A very standard TC in the S2. The S2 came with a middle close and a 3.9. The Plus2 had a middle close as well, with a 3.77. I was able to buy a close ratio, which I planned for the S2, but had the engine out of Plus2, and decided to try the close ratio in the Plus2, as I had just installed a 3.5. For the package, I love it. The Zetec was a replacement for a flamed out TC in the Plus2. The whole engine thing was a hacked up mess. I knew this when I bought the car. As a tickler, in the front Weber carb, the auxiliary venturi in the number one cylinder was melted.

Hmmm, Rob, spose there was a seating problem on the #1 intake valve????

Along that vein.....what were the years for hydraulic and solid cam followers in Zetec's? Valve clearances sound as if they could be a problem on a Zetec as well.

Kurt

The US silver top, metallic cam cover and two part sump, engines up to 5/98, had hydraulic buckets. From then on, the black, plastic cam cover and one piece aluminum sump, had the solid type.
My cars TC engine, recently re-built, was a mash up, tall block, cartridge water pump, and a Stromberg head that had the intake manifolds cut off and a Weber style intake welded on. It took a while to figure out what happened with the melted venturi. The car was a late 72 version, with the revised version of the fuel tank breather. No up and over with the vapour producing tubes, a single small tube that ran from an auxiliary vapour tank, forward along the left side chassis rail to a charcoal canister that then ran to the intake manifold to dispose of the fuel vapours. The line was plastic/nylon and was tucked up up under the flat top of the chassis rail, fairly close to the exhaust down pipes. With the dreaded process of removing/installing the exhaust down pipes, frustration must have regained supreme and a flame wrench was employed to cut a half moon chunk out of the top of the chassis rail. This misguided action melted the vapour line sealing it completely and securely shut. So...... when the PO had finished all this work, and took the freshly rebuilt re-built car out for its first drive, the fuel tank was now completely sealed, and as the fuel pump started drawing fuel, at some point it could draw less and less fuel, which leaned out the mixture to the point things started melting. I have not removed the old cylinder heat to inspect the damage. Do not need to know what the end result is, and what is left still useable, but it is just spare parts for some future project.

Ah, yes, the old 'Flame Wrench'! Very familiar with those kinds of annoyances! I 26R'd my frame and made allowances for header clearance in the process.

Kurt