Page 40: Some Engine Stuff Starts. Again.
March 2025

It's March already! Progress slowed a bit this year, but picks up on the engine and interior. I didn't realise how many small decisions must be made in reupholstering the interior. Should the inner part of the instrument bezels be the same as the dash, or use the contrasting lighter color? Matching stitching or different color? Grab handle the same on both sides, or different? Lamborghini changed the color schemes used in the S and SV, so which of those do I adopt? Most of the decisions come down to personal preference with a bias for the original colors with an S theme. The factory records list the interior color as "Mustard" and I've seen some swatches of that color. I just don't like the yellow/orange tinge, so I've picked a nice tan instead. Bobileff was able to find the original vinyl and I was leaning towards using that, but later he said that the factory did not build a car with both vinyl and leather used in the interior. After some deliberation I decided to go all leather and a nice brown leather was found that looks close to the vinyl.

P400 and S bezels

SV bezels

The most significant development is that (as mentioned last page) I pulled the engine from Vintage Lambo, LLC and gave it to Bobileff. There were many reasons for this decision, but the catalyst was that Vintage Lambo had the engine for over a year and a half and very little progress had been made. On top of that, communication was abysmal as was record-keeping and invoicing. Other issues surfaced as I inventoried the returned parts and Bobileff evaluated the work that was done. Unfortunately a lot of work from Vintage Lambo has to be redone. This ranges from small things, like the safety wiring on the differential gear, to important things like the brake master cylinder, which would have failed in use.

This came back from Vintage Lambo. When asked about it, the reply was "This is how the factory did it.":

While that may be true, here's how it was correctly redone by Bobileff:

This is a very minor example, but there are much more serious and expensive problems that need to be fixed. The valve work must be completely redone and the block needs to be re-resleeved, replacing the new sleeves that Bobileff installed years ago. I will refrain from detailing my disappointment until the lawsuit is settled. 'Nuf said.

Pistons are on order from Carrillo, the same company that made my rods. (JE Pistons were also considered. Either would be a great choice.)

To Split or Not To Split? That Is The Question.

Splitting a Miura sump has always been a topic of debate, with pros and cons on both sides. The standard case for splitting is to isolate and optimize lubrication for the engine and transmission. I've heard the reason the factory split the sump in the last 96 SVs is that they were planning to install a limited slip differential, but that never happened. I don't know how true this is, but separation certainly prevents cross-contamination that may cause premature wear. The factory did it. All sounds good, but are there downsides?

Arguments for:

1. Optimizing lubrication (viscosity, composition) for the engine and the transmission is better for both sides.
2. Keeping contaminants (metal fragments, synchro dust, etc.) isolated to each side minimizes wear.

Arguments against:

1. The transmission is primarily lubricated as the gears, partially submerged in oil, transfer oil to the other gears. This is called "splash lubrication." One of the holes in the rear head (under the rear cam) drains oil to the transmission. This is plugged to split the sump. There is a claim that the oil drips onto the gears and provides some lubrication. When the car is stopped and the clutch is depressed, the transmission stops spinning so splash lubrication stops. The claim is that the oil that drips from the head provides critical lubrication at standstill with the clutch in, and plugging it can cause transmission damage.
2. With a shared sump, there is a lot of oil available to the engine. When split, less oil can mean oil starvation under hard cornering.
3. Transmission fluid takes longer to warm up, so shifting is a bit sluggish.
4. It's difficult to seal the engine completely, so some oil can leak from it into the transmission.

Rebuttals:

1. Oil from the head doesn't actually drip onto the gears, so there is no benefit. At idle with the clutch in, the transmission doesn't need much lubrication because it's not spinning.
2. In a split-sump car, the engine fill line on the dipstick is higher. (More oil is added). The lack of baffling in the pan contributes more to oil starvation under cornering than oil level. One mitigation is to add baffling to the pan.
3. Wait a while - drive gently - to let the engine and transmission fluid warm up before trying to shift quickly.
4. Minor leaks may be inevitable, but probably inconsequential.

Here are the four holes between the engine and transmission that are closed to split the sump. (This can also be seen on Page 14.) Several other steps are needed to fully separate the oils.

Bobileff said the car should be ready by August to take to Monterey this year. I would be SO excited if this happened, but I've been wrong so many years before. We'll see how things progress in the next few months. Most of the remaining work is the engine and interior. Stay tuned.

3/26/25: The Headliner Goes In!

I stopped by the shop yesterday to see Luis working on the headliner. This is the start of the interior installation. It was great to watch him work for a while and chat. He said he has done about 30 Miura interiors over the years. Truly one of the best.

4/4/25: The Overhead Console is Connected

Switches were found that still have the symbols on them (instead of all rubbed off) so there is some hope of learning what each one does. It was exciting to see the electrical system hooked up and tested so all the switches actually turn things on. It's as if the car is starting to come to life after so many dormant decades.

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