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Internal Combustion Engine

ciechanow.ski

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Re: Internal Combustion Engine

#151

Post by mgarfias »

kingsuper20 wrote: post #124
mgarfias wrote: post #109

Earlier quoted context omitted.

Huh? What do you mean "takes off". Do you mean do we build LS motors now instead of gen1/2 SBCs then yes. If you mean "do the LSx heads drop onto a gen1/2 SBC", then no, not at all. only thing common between them is the cylinder spacing. The LS uses 4 bolts per cylinder like a ford, instead of 5 like the SBC, the firing order is different, the valve layout is different (ports are symmetric vs mirrored), etc.

Firing order is something of an arbitrary thing, it's been done on SBC for some time. There are small block Chevrolet blocks that accept LS heads (Bill Mitchell maybe?) (note: I wasn't referring to box-stock LS heads on a box-stock SBC)

Mostly what i've seen is making the SBC take a symmetrical head. Saw some INSANE CFE pro stock heads at the machinist last year, he was building them in a large bore, short stroke deal setup for bonneville to run like 11krpm.

Re: Internal Combustion Engine

#152

Post by slver »

specialp wrote: post #15

I just built an engine for my car. One thing I gained an appreciation for was how CHEAP cars and engines are. There's probably nothing else with as precise machining that is as inexpensive. Engine cylinders are honed to accuracies that are less than 1 thousandth of an inch. Crank journals as well and rod journals. This is all precise machine work with metal. I use inches here because in machine work thousandths of in…

How about your phone.

Re: Internal Combustion Engine

#153

Post by fuzzybear3965 »

wyuenho wrote: post #134
bob1029 wrote: post #20

Earlier quoted context omitted.

view-source:https://ciechanow.ski/js/ice.js I find this to be a very impressive implementation.

I wonder if it's completely written by hand from scratch or done with something like emscripten.

He said on Twitter that he hand-wrote the animation code.

Re: Internal Combustion Engine

#154

Post by Alupis »

elihu wrote: post #121
esaym wrote: post #93

Earlier quoted context omitted.

> EVs don't need a catalytic converter, so that's a big thing in their favor. I feel there is some sort of scam going on with catalytic converters for the last few years. I actually worked in a small family owned auto shop in the early 2000's. If a car came in with a clogged cat, we'd first fix the source of the issue (usually a mis-firing cylinder allowing raw fuel into the exhaust) and then we'd cut out the cat, an…

I don't think cats are to address greenhouse gasses; they're focused more on reducing pollutants that affect local air quality and human health. The main greenhouse gas from a car is carbon dioxide. The amount you create is directly proportional to the amount of fuel you burn. I don't know why modern cats are expensive; it might have to do with the price of platinum, palladium, and so on, and the relative amount of t…

> A cheap generic cat might have the bare minimum amount of catalyst, and might not do a very good job

It depends on the car/engine. My old Mazda RX-8 had a huge cat - longer than the muffler and cost me $2,000 to replace (including labor) back in the late 2000's.

The rotary engine in that vehicle had a terribly difficult time passing California's emission laws even when it was brand new off the lot - which led to strange "hacks" including a blower motor that moved high volumes of air through the exhaust to heat the cat sooner and somehow improve it's numbers, among other things. I assume the extra-long cat was part of the shenanigans Mazda had to go through to get it compliant.

Re: Internal Combustion Engine

#155

Post by alexvoda »

formerly_proven wrote: post #130
specialp wrote: post #15

I just built an engine for my car. One thing I gained an appreciation for was how CHEAP cars and engines are. There's probably nothing else with as precise machining that is as inexpensive. Engine cylinders are honed to accuracies that are less than 1 thousandth of an inch. Crank journals as well and rod journals. This is all precise machine work with metal. I use inches here because in machine work thousandths of in…

> I use inches here because in machine work thousandths of inches is the language du jour. Only in the USA ;)

The rest of the world figured that using prefixes with a predefined universal multiplier is more practical.

Therefore you can use the milifoot equal to a thousandth of a foot, or the kiloinch equal to one thousand inches, or the microyard equal to one millionth of a yard, maybe even the centifurlong equal to one hundredth of a furlong.

We are quiet proud of our prefixes. Now if only we would decide on a single reference unit to which to apply the prefixes. Conversion from megainch to hectofurlong is rather inconvenient.

Re: Internal Combustion Engine

#156

Post by labawi »

distortedsignal wrote: post #104
londons_explore wrote: post #45

Earlier quoted context omitted.

> Additional cost for regen brakes of course. Regen braking has no physical cost associated - it's pure software/firmware. The exact same hardware that is used to power the car forwards can be used for regen braking. It can be as simple as a single negative sign in the code to cause the phase to be 180 degrees out, current to flow backwards, torque to go the other way, and the battery to be charged instead of dischar…

> Regen braking has no physical cost associated - it's pure software/firmware. I think this is a slight exaggeration. The way I understand regenerative braking is that you (effectively) run your AC generator in reverse of what you would in order to accelerate in the direction of motion and then take the current generated by that, rectify it to DC, and use that current to charge a battery. The energy in the system is…

I think you are overestimating unique requirements of typical car engines. They are usually DC powered AC engines, where the DC->AC converter (generating 3-phase AC of controlled power and frequency) can probably run backwards (AC->DC) with at most a few minimal hardware changes, if any.

If you're not overdoing regen, you probably don't need additional balancing. Even if you wanted to charge the EV by towing, you could probably use the normal charge balancing circuitry, again minimal if any HW changes. Non-wimpy batteries and cells should be fine - if they can fast-charge, they can take regen. Might have some limitations on acceptable power vs. temperature, charge state etc.

Re: Internal Combustion Engine

#157

Post by kokanator »

specialp wrote: post #15

I just built an engine for my car. One thing I gained an appreciation for was how CHEAP cars and engines are. There's probably nothing else with as precise machining that is as inexpensive. Engine cylinders are honed to accuracies that are less than 1 thousandth of an inch. Crank journals as well and rod journals. This is all precise machine work with metal. I use inches here because in machine work thousandths of in…

Anyone who has the inclination to build an engine, should.

It is super rewarding not to mention you get to buy a bunch of really cool tools.

I build a 350 Windsor from the block. The research and design decisions were one of the best parts of the project. Then to put it all together and realize the power was amazing.

Re: Internal Combustion Engine

#158

Post by jcoby »

tmh88j wrote: post #129
zeusk wrote: post #117

Earlier quoted context omitted.

They're meant to be dual duty. There aren't any road car engines I'm aware of that use individual throttle bodies or 12+ compression without direct injection.

The S54 engine which came before the S65/85, was also high revving, had 11.5:1 compression ratio and didn't have any of the rod bearing issues. The 20v Toyota 4AGE also had them too with a high compression ratio.

The S54 absolutely had rod bearing issues. There was a recall on the 2001-2003.5 M3s to replace them and BMW switched to 60w oil as part of the remediation. They’re still having issues to this day.

The S54 is also notorious for VANOS issues and cam drive failures. I had to replace the solenoid pack on mine but elected to not upgrade the drive while I was in there.

Re: Internal Combustion Engine

#159

Post by Severian »

Grazester wrote: post #113
specialp wrote: post #67

Earlier quoted context omitted.

Yes you are right as far as LS engine builders there's loads. I could have ordered a crate engine from Texas Speed and been done with it. And yes for hours of my time spent vs hours of money saved I lost a ton of money. But all it takes is one very small mistake to make an engine short lived with these exacting tolerances. I'd rather blame myself than deal with someone kicking the blame back. It was also a personal s…

I have a buddy that is adamant about not flushing transmissions if you dont have a issue because he think its guaranteed to have an issue after, from his experience. lol

There is some truth to that, but not never. A flush will dislodge any metal shavings and crud from the moving parts. The filter should catch these, but the filters themselves can get clogged, and then bye-bye transmission.

Flushing can really be bad if you've never done a routine flush on a schedule. You don't want to go 150,000 miles before your first one. You would need a garage with a forced flush system to move it all out, and then probably flush again soon after to make sure all the gunk is out.

Transmission oil breaks down with heat and wear like any other, and will eventually contain sludge and dirt.

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