The revival of 650143R, 1970 with TS.

[jbcollier]

77mm bore = 1565cc.  Those look to be "higher" compression pistons, at least in the 10.25:1 and up range.

(77.8mm = 1596cc, 78mm = 1605cc, 79mm = 1647cc)

[GavinT]

Did not get to take my measurments but this may help?
Looks like standard bore with a compression bump.
We used to call such pistons "Pop-up's".

Hmmm . . can't see the piston top properly at that angle.
But pick a likeness out of these:

Left: Alpine 1796 (82.5mm) piston - ignore this one.
Middle: R12-Gordini piston -  coming in at about 12:1 (allegedly) before you relieve the combustion chamber etc.
Right: R17-TS piston - slight dome for 10.25 compression.

A dead flat piston top is what the R16TS came with and is variously quoted around 8.6 or 9.0:1.

[Richard48Y]

I never did get direct contact info for the guy who built this engine.
I was told it's about 11.5/12-1 and turns 8K RPM.
Middle piston is closest match but not exact.
Dome profile is consistent all the way across the top.
You may be able to get a better idea looking at the valve pockets.
Once I am able to bring them to TDC I will get a better pic.
Very little ridge in the cylinders so I may be able to just re-ring this engine.
If not I suspect that finding matching pistons will be a challenge.
What I have now are German made, Sach's?
JE will make a new set for $1K, a set of V8 pistons are $1K.
Maybe get two sets made for the price of one?

Going to clean up my lathe so that I may make some spacers to hold the cylinders down.
Cannot get totally immersed in the Lotus right now so pulling the engine will have to wait.
Need to get my MIG welder back in action to make the cradle that will stand in for the engine and trans.

[GavinT]

Two more shots of the same participant line up but at different angles.

The middle piston is out of a F2 Renault powered car which explains the deep valve reliefs . . and also obscures the original shape.
The profile has a quite pronounced middle section bump above the principal radius but it's not a smooth radius across the whole piston . . if that makes sense.
These OEM Renault 12-G pistons have a similar profile to the Wossner's - last pic.

But I've also see aftermarket versions where they do away with the Renault "hump on a hump" look. e.g. Mecaparts.

Installing these pistons mandates head clearance relief of the squish area.
Anyway, cc-ing the whole thing should tell the story.

I have a Sachs race clutch out of that same F2 Renault car around here somewhere.
Do Sachs also make pistons?

[Richard48Y]

I was probably thinking of Mahle.
Need to find a solvent to use in my parts washer that does not affect aluminum so that I may clean up the head.
Curious to see just how Ported it really is.

[Richard48Y]

Finally got my cylinders locked down so that I may turn the engine over.
That let me get more pics of the pistons.
Dome is not so extreme as expected.
Maybe some one here can interpret the markings?
Might reveal maker and compression?
Make a cast to measure dome?

Engine tag.

Also noted that the shift rod sits Very close to the engine block and have to wonder if this is normal or needs correction?

[Richard48Y]

Wiring has been a topic here lately.
Decided to look at mine, in part to see how bad a job it is going to be to fix up another Europa.
Access seems not so bad as some horror stories make it out to be.
But my own wiring may be due for a new loom, I see some sort of trailer wiring module being used for turn signals. Not a good sign.

[RoddyMac]

I see some sort of trailer wiring module being used for turn signals.

That should be the DB10 relay, used on various British cars (your MM might even have one).  Though it is possible someone replaced it with a trailer module, all it is two dpdt relays.

[Richard48Y]

Not able to do anything major with the car at the moment as I have a pretty hefty bill coming due at the machine shop for a couple of non-Lotus engine builds.
Still looking for some small parts to restore the car to a more original state.
Recently got a set of bumpers, rear is very good, front is easily (?) repairable.
Trying to decide if I want to chase down all the badging the PO removed.
I always find them annoying when trying to wash and wax any car.
No plans to sell but eventually I will be unable to enter and exit.
At that time resale value becomes more important.
Would having the badges and letters in a box make that much difference?

[BDA]

When I had my bumpers rechromed, I had my front bumper straightened. I don’t remember how bad it was, but I don’t think it was too bad. Anyway, the chrome guy said he could bend it back the way it was without another to compare it against. He did get it pretty close but the end sticks out about 3/8”, maybe less on the end that had been hit. The interesting thing is I’ve seen a similar situation on other Europas. Maybe the same guy straightened their bumper or the guy who did theirs used the same technique!

[Kendo]

The front bumper I sourced had obviously been used to stop the car. L-shaped from above. I was amazed at how the chrome shop could straighten it so well without a sample. In my case, it was ~1/4" too tight, and scraped the paint, which is being replaced anyway, so no big deal.

[jbcollier]

Before they do the final polishing and plating, get the bumper back and try it in the car.  Easy to resize before the final steps.  I did that with mine and had them widen the front by a 1.4”.

[BDA]

There are very few places (comparatively) that do real chrome plating any more. The funny thing is that I found a place out of town - I don't remember where they were - who would do my bumpers. I had my wife ship them to them and they gave me an estimate. I waited a week or two and hadn't heard from them so I called. He said, "Oh, I didn't know you wanted us to do them!" I thought, do you really think I'm going to send my bumpers to every chrome shop to make sure I get the very best deal?!!

As I say, he did a pretty nice job. I wish mine had come in as tight as Kendo's but they're fine.

I also want to give a recommendation for Quick-Glo chrome cleaner and polisher (www.quick-glo.com). I saw it on Jay Leno's Garage and bought some. The chrome covers for my K&N air filters had some small "stains" in the chrome so I thought I'd give it a try. I didn't use it them but when I was washing and waxing my car the other day, I saw some "stains" in the chrome on one of my bumpers. You couldn't see it from more than 5 feet away but I was still bummed about it. I tried some Quick-Glo and it really polished my bumpers up very nicely!!! I'm very impressed with it!

[Richard48Y]

Finally got to buy some parts beyond mere bumpers or lenses.
New cam followers are on the way.

[Richard48Y]

Now that I have my not easily sourced new cam followers what should I make a point of doing next?
Pull the cam for exam, get the head rebuilt?
Trying to make a point of addressing the items most difficult to obtain first.