Geely: 48.4% thermal efficiency. 106mpg

[Logic]

The idea here is to explore how Geely got to 48.4% as time allows. (and not forget to! )
Series hybrid with direct drive top gear And
small battery..! (Always on engine?)

Just some links atm. No time!

https://autoexphub.com/geely-i-hev-4...id-technology/

https://www.motor1.com/news/793204/g...engine-record/

https://www.autoevolution.com/news/geely-says-ai-helped-it-create-the-most-efficient-internal-combustion-engine-ever-252980.html

[Logic]

Another almost? always on, large genset, small battery, Series Hybrid:

https://www.youtube.com/watch?v=tdTpYNpZHig

I NB that tuned length intakes and exhausts only work for around a second, 5 times in the std urban cycle.
So manufacturers go for simple, cheap, light instead.
When you are at optimal rpm and load 100% of thetime, that math changes!

Grok:
Constant RPM & Load in a Series Hybrid Genset – Why Tuning Finally Makes Sense
In normal cars the engine is only at any specific optimal RPM/load for a very short time (e.g. ~1 second, 5 times in the standard urban cycle). That is why manufacturers go for cheap, simple and light designs instead of aggressive tuning.
In a series hybrid range-extender (genset) the engine can run at one chosen optimal RPM and load 100% of the time it is on. This completely changes the math.
Intake Tuning at the Design RPM
Properly tuned fixed intake runner lengths (using wave resonance / Helmholtz tuning) can deliver:

5–12%+ improvement in volumetric efficiency at the target RPM compared to a typical compromise production manifold.
Peak gains in some studies reached 8.7% VE at the chosen mid-range RPM.

Because the genset stays at that RPM, you get the full benefit all the time.
Exhaust Tuning
Exhaust primary pipe length and collector tuning gives smaller but still useful gains:

Typically 2–6% improvement in torque / scavenging at the tuned RPM.
Intake + exhaust effects are largely additive.

Combined Effect
At a single optimal RPM/load point, dedicated tuning of intake + exhaust + combustion chamber can realistically give 8–15% better fuel economy (lower BSFC) compared to a standard untuned or broadly-compromised automotive engine running at the same RPM.
This is exactly why some range-extender projects aim for 35–40%+ thermal efficiency at the genset level — something very hard to achieve in a normal variable-RPM car engine.
Bottom line for genset use:
Normal car → “tuning is hardly worth it”
Genset → Yes, tune aggressively!

[freebeard]

The Alessandro Volta is one of my favorite cars. The midengined Hybrid Synergy Drive appeared in the Prius GT racer.

Originally Posted by DDG

Road & Track
https://www.roadandtrack.com/car-cul...r-gt-race-car/How the Toyota Prius Became an Unlikely Racing Hero
Not just any Prius, the Prius GT was a mid-engined V-8 monster, fitted with impressive aerodynamic addenda on a highly modified racing chassis, but still incorporating a near-factory hybrid drive ...

[Logic]

Not done here! There are other reasons the Geely engine gets 48%.

DLC (diamond like coatings)
Well there's a"
"Just pour it into the oil"
easy treatment that gives you a ceramic layer that's:

• 85% the hardness of diamond and ~100x more slippery than metal-oil-metal.
• Self replenishing should it be worn or scratched off.
• Treats ALL your 'in oil/ed' cylinders, bearings, valve-train etc, not just the sleeves and piston sides.
• Turns the enemy of engine lubrication: Water, into your greatest ally.

Buuuut; NO-ONE believes it!
Too bad; Your (6%+ economy and huge longevity) loss...

AI designed intake to get max turbulence in the combustion chamber.
The why's of max turbulence and squish is a 'Magnum-Opus' all of it's own!

Other..?

[freebeard]

Not done here!
...
Well there's a"
"Just pour it into the oil"
easy treatment that gives you a ceramic layer

I admire your persistence.

If I source the ingredient, I'd administer it to the XFi, but I only see a few hundred miles of use going forward. I'm coming around to selling the Superbeetle as is.

[Logic]

Originally Posted by freebeard

I admire your persistence.

If I source the ingredient, I'd administer it to the XFi, but I only see a few hundred miles of use going forward. I'm coming around to selling the Superbeetle as is.

Cool! (Er... XFi?)
BA @ Walmart! https://www.walmart.com/c/kp/boric-acid

NB: B2O3 preferably printed on the box
NOT! Borax
This one looks good: https://www.walmart.com/ip/PF-Harris-Boric-Acid-Indoor-Roach-Powder-Killer-with-Applicator-16-oz/26779793?classType=REGULAR


Try get the finest powder you can. (not a deal breaker)
A small coffee grinder that fits in your freezer is handy, but also not a deal breaker. (For making the powder fine.)

If you tell me how much oil it takes; I'll give you a 'How much of what' etc.

[freebeard]

DDG says 3.5 quarts. I'm Okay with Walmart since Amazon is bigger and badder, but I've seen things on their website that aren't available in the brick and mortar store.

My question is how would I know the difference with few miles driven. Would it sound quieter?

[Logic]

Originally Posted by freebeard

DDG says 3.5 quarts. I'm Okay with Walmart since Amazon is bigger and badder, but I've seen things on their website that aren't available in the brick and mortar store.

My question is how would I know the difference with few miles driven. Would it sound quieter?

Assuming it has some miles on it (well past run in) for all this.

You have a feel for the vehicle.
How fast the engine turns over on the starter.
The vibration coming through the gear lever etc.
The sound, yes.

You will notice it turn over faster on the starter.
Less vibes through the gear lever etc. A general 'smoothness, to the mechanical side of the sound too.

Also general pep: less throttle for the same go.
And around 6+% in fuel economy. (going by the studies. I never really checked beyond: 'Hmmm!? seems better')

Oh:
Your beetle will be more saleable. (More money for it. I saw this in a Nissan 1400 'bakkie')
Compression will pick up unless its a burnt/leaky valve.

(The check for that is a compression test.
Then another, but with 2-3 squirts of oil in the plug hole.
If compression picks up noticeably with the oil; it's piston - rings - sleeve.
If not; it's valves)

In a lot of ways it's a great/better contender.
If it's really old and worn; good!

Instructions for 3.5 Quarts coming up...
Any drug store should stock it.

[Logic]

Originally Posted by freebeard

DDG says 3.5 quarts. I'm Okay with Walmart since Amazon is bigger and badder, but I've seen things on their website that aren't available in the brick and mortar store.

My question is how would I know the difference with few miles driven. Would it sound quieter?

For 3.5 quarts, you need ~100 grams of boric acid.

Instructions:
You want ~350ml of boiling water.
Stir in about 100g of boric acid. The first ~60g will dissolve easily — no need for it to be super fine.

That will leave 1–2 teaspoons of undissolved boric acid at the bottom.
This undissolved part should preferably be finely ground (coffee grinder, freezer trick) so it stays in suspension better and more passes through the oil filter.

Use a thermos or something quick to open without burning yourself.
Pre-heat it with boiling water, that you pour it out before it holds your mixture.

Shake the mixture well just before pouring, to get the undissolved powder into suspension.
Bring a spoon for any powder left in the bottem.
Add it to an engine that’s topped up with oil and warmed up.

Drive of immediately but gently for 10–15 km because the oil will be thinner temporarily.
You will feel it kick in:
The engine smooths out and more pep.
You can then drive normally (or really test it properly! &#128521.

Advice:

The safe approach:
Do this with new oil, after an engine flush to clear out any sludge.
(Using different oil brands can make a lot)
This stuff gets underneath sludge like nothing else, loosening it.
The sludge could block your oil pump pickup and/or filter.
Change the filter again after ~2 days.

At minimum:
You should change the oil filter before and do a proper oil service within ~2 days.


The coffee grinder, freezer trick:
You put your BA in the coffee grinder, then the whole ting in the bottem of the freezer for a good couple of hours.
This makes the powder brittle (freezes any moisture) and the coffee grinder more effective.
Take the grinder out and run a couple of bursts, while turning it this way and that.

Repeat.

When the powder becomes so thin it sticks to the lid, obscuring your view, you're about done.
Takes 2-3 goes.