Custom engine builders?

[fallenarch]

Do tell of this other tech. I'm only aware of a clutch or some version of a torque converter. I once read an article where an electrically charged fluid could change viscosity to lock up the drive.

[jellyrug]

Do tell of this other tech. I'm only aware of a clutch or some version of a torque converter. I once read an article where an electrically charged fluid could change viscosity to lock up the drive.

The title will most probably put you off, why it is missed by so many, but scroll down and play with the sliders and you will see no clutch no nada.

There is the option to take out the electrical motors and replace with hydraulic devices if battery weight is a problem.

BMW future prototypes with high performance is following the same concept. Besides efficiency, the main advantage is you can immediately spool up a high RPM motor into its power range and use the maximum available power that will not break wheel traction. Nothing slips, direct drive and no heat is generated and it is pretty efficient.

Another way to explain this is a gearbox without a clutch, with an infinite transmission ratio.

Toyota Prius - Power Split Device

[FlatlandBusa]

That's something that I've been mulling over. The torque-converter-based automatic prevalent in cars is an unholy mess of inefficiency designed to convert brake shoes into dust and gasoline into waste heat. (more so than the engine itself already does on it's own)

The engine I've described in this thread is a cut-down version of an engine that I'd eventually like to have in a car, and at one point I had considered starting my own car company. I may still do so in the future, but for now the automotive landscape is changing far faster than my ability to plan can keep up with. (And as an anarchist, I have no patience for government regulation) But I digress.

It occurred to me that not everyone has the mental wiring to handle a clutch. But how to avoid a slushbox? Computer-controlled clutch it was.

Yes the traditional torque converter is a terrible waste of energy all in the name of silky smooth drivability.

My wifes Focus has the 6 speed dual clutch (dry clutches so it is less complex compared to the smoother wet clutch setups like VW) transmission in it, it returns 28-29 MPG in town and 33-39 MPG on the highway (speed dependent).
I can tolerate the minor roughness and occasional shudder this transmission generates since it returns fantastic mileage with reasonable performance.

[TheAtomicAss]

The title will most probably put you off, why it is missed by so many, but scroll down and play with the sliders and you will see no clutch no nada.

There is the option to take out the electrical motors and replace with hydraulic devices if battery weight is a problem.

BMW future prototypes with high performance is following the same concept. Besides efficiency, the main advantage is you can immediately spool up a high RPM motor into its power range and use the maximum available power that will not break wheel traction. Nothing slips, direct drive and no heat is generated and it is pretty efficient.

Another way to explain this is a gearbox without a clutch, with an infinite transmission ratio.

Toyota Prius - Power Split Device

I suppose I'd have to see a working version to understand the principles of it. Explanations never jived with me much.

[TheAtomicAss]

Also, relevant to this thread, it's amazing the things you find when you twist your Google-fu the right way.

Just need to mount a bigger alternator.

[jellyrug]

I suppose I'd have to see a working version to understand the principles of it. Explanations never jived with me much.

Planetary gears is an old concept, what makes a difference today is the availability of advanced control engineering to use them to their full extent. By controlling the the different gears in the system, you can have infinite transmission ratios, both in forward and reverse, no clutch.

Here in the US, it is also referred to as Epicyclic gearing.

[fallenarch]

I guess I don't get the "infinite" ratios with the planetary gearing. You could have different ratios depending on whether you drove the little gears or the larger center shaft but the relative ratios are fixed. What am I missing?

[jellyrug]

I guess I don't get the "infinite" ratios with the planetary gearing. You could have different ratios depending on whether you drove the little gears or the larger center shaft but the relative ratios are fixed. What am I missing?

Play with the sliders on the previous link, it is pretty self explanatory.

Here is some more narrative, Nissan uses a design I would not use, but the output is somewhat similar. It is not planetary though and will not be as reliable.

Definitions: Continuously Variable Transmission (CVT) - Autotrader

What I like about it, is that if your motor develops maximum power at say 10,000 RPM, you can spool the motor up to 10,000 RPM out of the gate and keep it there until you cross the 1/4 mile line.

[TheAtomicAss]

Planetary gears is an old concept, what makes a difference today is the availability of advanced control engineering to use them to their full extent. By controlling the the different gears in the system, you can have infinite transmission ratios, both in forward and reverse, no clutch.

I meant that, without the gas guzzler, MG1 and MG2 in the models, I can't picture how the Prius uses this to do it's thing.

[TheAtomicAss]

Here is some more narrative, Nissan uses a design I would not use, but the output is somewhat similar. It is not planetary though and will not be as reliable.

Definitions: Continuously Variable Transmission (CVT) - Autotrader

Actually, no, those things SUCK power pretty badly. I've put 26,500 into the Burgman 400, and it's single has a lot of potential which is wasted on the CVT. And at least in Suzuki's variation, it was not possible to achieve high revs until sufficient velocity had been gained, with the engine staying below 5k until well past 35 mph.

ETA: I'd honestly buy a new Burgman, if they could stick a manual in it and throw in some hydraulic lash adjusters.

[motonutz]

10 grand, the only build ull get for that is a bike with a whole drilled in the air fiter box.when u said 10k u lost everyone lol, and todo something comparable to a 650, why? the fellows including me thought u were talking about what i ACTUALLY did.

At my home track i race a 9.99, 9.50 index classes, crazy 8s, an pro bike n sled. ( Ihave Busas for each class) Then they said a new, street legal heads up class was comng the next year, What a perfect opportunity to do a real custon bike and engine build! i knew it was a money class. The one with the most money and least brains to put it 'ALL INN' the build would win.

And i won. i may have the worlds quickest, and gorgeous Hayabusa. it is still street legal, the engine is an original 1625cc stroker. over 300 hp!!! @311hp the rear wheel started spinning (shredddding) on the Dyno. we called Dyno Jet and they said 'add 20hp' Bike weighed 500 lbs. to start and now weighs 435lbs.

The bike took a year to build. spent $15,000 just in shipping all over the States and Canada. The paint on the bike took 4 1/2 months, min 60hrs a week.

Take a look at my profile pics, and there u wil see one of the sickest Hayabusas. In the World...

[TheAtomicAss]

10 grand, the only build ull get for that is a bike with a whole drilled in the air fiter box.when u said 10k u lost everyone lol, and todo something comparable to a 650, why? the fellows including me thought u were talking about what i ACTUALLY did.

Well, unlike typical reasons for building a truly custom, from the ground up engine (HP bragging rights), my goal is to test some theories rattling around in my brain meats, that if correct, (and the builder was competent in his craft AND tuning), would give me MPG bragging rights. Plus, if you've happened to glance at the doc, said engine has 12 CYLINDERS. There are some smooth bikes out there, but I seriously doubt any that are that smooth.

Now, that being said, I've put a fully custom engine on the back burner, but I have a new, more reasonable project to tackle. I've been doing a bit of reading into the Prius engine, and the special cam profile it uses to effectively transform itself from an Otto cycle into an Atkinson cycle engine.

So what should I expect to pay, (ballpark) and what are some good shops to consider to get a cam ground to my specs, plus a tune?

[ali123]

Stultifying, is a brief way of describing the last five years.

As far as my budget and the engine, I want to say $10k? But that could be flexible. As for the design? I made a Doc. And I was talking specifically about a motorcycle engine, I'm just not sure what chassis I plan to put it in.

And the goal is to prove a theory I have, that larger cylinder counts are more thermally efficient than fewer, and to try to get >150mpg on the roads with a reasonably powerful engine.

old thread... but I got a good laugh here.... 10 grand fellas.... lol

[bigoltool]

3D printing will soon make this type of project commonplace. Ability to rapidly itterate designs without need of costly tooling or machining(mostly).

[ali123]

no way

[sixpack577]

3D printing will soon make this type of project commonplace. Ability to rapidly itterate designs without need of costly tooling or machining(mostly).

+1
a casting mold will be cheap and easy to make. And aid in R&D on forged and milled parts.

[ali123]

how long... how many years? u guys betting men?

[sixpack577]

How about now

[sixpack577]

It's not common place, but already being done.

[bigoltool]

F1 guys are printing parts on race weekends now.