[Niku-Sama]

so ok i was cruising craigslist and saw a few metros popped up recently. i'm getting down to the point where i need to get something before my car gives up on me so i can fix the dang thing. it'll take me several weeks i am sure of tedius connectore replacing, injector replacing, fuel rail fab, clutch slave replacing, chasis bushing replacment, clutch replacment....the list kinda goes on.... its a 30 year old car.

i've always wanted to get some chepo econobox and modify it for power and/or MPG and see what i could get out of so for fun i went looking for mods on this metro. i'm assuming its a 3cylinder metro but who knows for sure

i came across this through some people cutting grooves in cylinder heads

http://www.somender-singh.com/

it sounds interesting, i assume its possible for some gain as i can imagine the piston comming up squeezing the mixture through the groove and mixing it up more evenly and channeling it twards the spark plug.

but at the same time the spak plug fires for how long? and this talk about "nitrogen" wheres the nitrogen comming from when both valves are closed?
what about those corners that can heat up and stay hot and cause pre-detonation?

i dont know, i guess i wont really untill i try it.

i am always worried about such sites that put so much emphasis (literally, look at the underlines and bolded wording) that are trying to play science professor with fake science and no real results.

i guess i could try it, a metro head shouldnt cost very much

[Mother Goose]

Originally Posted by Niku-Sama

i am always worried about such sites that put so much emphasis (literally, look at the underlines and bolded wording) that are trying to play science professor with fake science and no real results.

Well, it looks like you do have some cause for concern (that's one of the most ridiculous sites!).

But just do a google for his name and tons of sites pop up. The comments in this one are interesting, including, apparently, the writer who had written the original article on him.

Hi all- Charles Graeber here, the guy who went to India and wrote the story on Singh for PopSci. (I'm a contributing editor with Wired too so I'm not sure that it appeared there- Singh came to my attention through a personal contact who happened to know Singh socially in Mysore). I'm just jumping in because, firstly it's interesting to me that so many have read this story, as I certainly haven't heard much of it, and secondly, to address a few of the above questions. I too would like to see the dyno #'s, and worked hard (without success) to secure them. I suspect, as one writer commented, that Singh has a good cheap improvement which can easily be realized for the majority of dirty workhorse engines which power the planet. He may have something more there too, but it's impossible to determine that without expensive scientific testing which, as far as I know, Singh has neither carried out nor allowed, for fear of proprietary loss. I'm intrested to hear from people in this country who have carried out Singh's mods; what sort of results did you get, and which engines did you mod?

[donuts]

I remember reading about this @ hotrodders.com. To me it didn't seem like there was a definitive answer as to whether they worked or not, but some folks swore by them. I was toying with the idea when I swapped heads on my old pick-up last summer. I'm curious though, If I had a spare set of heads, I might try it...

[FudgeNuggets]

Not much you can do with stock cars to get better MPG. I mean people even argue whether or not Cold Air Intakes contribute or not. Better flowing exhaust definetly will too. What really kills me though is how much the EPA screws us over on MPG. The Ford Fiesta on Europe gets like 60+mpg and by the time the EPA gimps it here with all their emmissions garbage BS then it'll get less than 40mpg. Only VW and select Mercedes and BWMs will sell diesel cars here because of the EPA and even then they're gimped to get 2/3 of the mpg of what their European counterparts do.

65mpg European Ford Fiesta:
http://www.wired.com/autopia/2009/02/ford-will-give/

40mpg US model:
http://www.autoblog.com/2009/12/02/2...d-hits-40-mpg/

[Quigsby]

Originally Posted by FudgeNuggets

65mpg European Ford Fiesta:
http://www.wired.com/autopia/2009/02/ford-will-give/

40mpg US model:
http://www.autoblog.com/2009/12/02/2...d-hits-40-mpg/

The Euro-model is diesel while the US one is gas/petrol. Diesel one has a turbo - weeeee!

Yeah, turbo diesel sounds great. Trucks have used it forever.

[FudgeNuggets]

Originally Posted by Quigsby

The Euro-model is diesel while the US one is gas/petrol. Diesel one has a turbo - weeeee!

Yeah, turbo diesel sounds great. Trucks have used it forever.

Right, but you can't even get a diesel Ford car in the US.

[Quigsby]

Originally Posted by FudgeNuggets

Right, but you can't even get a diesel Ford car in the US.

Yeah, but I think it's due to the diesel 'scare' of the 80's when cars used to pour black smoke. Car companies like Volkswagen have had a TDI model available for years. My only personal concern with diesels are gelling, but that's because temps hit -30 here (actual) during the winters.

[Cowboy Shane]

Is there a better source for reading up on this? I tried the link and managed to notice the 40% efficiency gain stuff was for side-valve engines. Are those still being used in some cars somewhere?

[Bobnova]

No modern cars use flat heads (with the valves on the side). Only lawn mowers, and really very few of those. He mentions those just so he can say 40%.
If you look at a modern four valve cylinder head there aren't the wide squish bands to cut slots into, making the whole thing fairly irrelevant.

It doesn't increase efficiency much anyway, unless you're in 1930's engine technology land.
It does lead to better mixing, however at the same time it lowers the compression ratio. The end result is a tiny gain or no gain at all.

You can use it to allow a higher compression ratio to be run with a given grade of fuel, THAT increases efficiency.
The nitrogen statement has absolutely nothing to do with anything.
Air is mostly nitrogen, him saying that he's using that nitrogen to distribute oxygen is like saying that your lungs pump nitrogen to distribute oxygen. It's kinda true, sorta, but not really.

This is slightly better then the "runs on water" things (total fabrication), but not much.


One of the main problems is that you need all four combustion chambers to be as close to exactly the same as possible, if they aren't you can't tune the motor correctly and either lose efficiency tuning for the bad cylinders, or kill the bad cylinders tuning for the good ones.

Modern diesels still rattle and smell terrible, even brand new ones. I spent some time driving a vw TDI. It feels like it has lots of power but because they set the throttle pedal so that 10% movement equals 50% power increase, but if you actually put it all the way down it becomes obvious that it has the same amount of power as every other 102hp car out there (funny how that works).

[VinnyTAMU]

I have improved my average MPG (CITY) in my 2006 Honda Civic from 28 MPG Average to 32 MPG Average just by implementing hypermiling practices when I am driving.

http://www.hypermiling.com/

[nd4spdbh2]

Originally Posted by Bobnova

Modern diesels still rattle and smell terrible, even brand new ones. I spent some time driving a vw TDI. It feels like it has lots of power but because they set the throttle pedal so that 10% movement equals 50% power increase, but if you actually put it all the way down it becomes obvious that it has the same amount of power as every other 102hp car out there (funny how that works).

Diesels are so much more efficient and generate so much more power its not even funny. Its truly a shame that we cant have them here in the USA... although it seems to be turning around with vw and audis tdi's... but even then they are bastardized versions of the rest of the world counterparts. I really dont understand why people still think diesels are dirty loud terrible smelling things... when in fact they produce less emissions, produce more power, and are much better on gas than a gasoline equivalent.

My buddies 2002 chevy 2500hd 6.6L duramax was dynoed not long ago at 711hp and 1024ftlbs of torque... and he makes 22mpg around town... my 2001 chevy 2500hd with the 6.0L gas guzzler makes all of about half the horse power and a third the torque... yet uses twice the gas.

It becomes even more aparent in smaller cars. An audi q7... the 4.2L gas motor vs their 4.2L TDI. 350hp @ 6800rpms for the gas, 340hp @ 3750 for the TDI. 320ftlbs @ 3500rpms for the Gas... 561ftlbs @ 1800-2500rpms for the TDI. 22.2mpg for the gas... 28.5 for the TDI. 302 g/km of c02 for the gas... 262 g/km for the TDI.

So in the same car with a same displacement V8 motor... you have the TDI with 10ish less horsepower... but 175% more torque, 6.3 better mpg and 15% less emissions.

[Bobnova]

They are somewhat more efficient, in the 35-40% range compared to 30-33% for gasoline. The 40% diesels are stationary motors that have a 300rpm window. Diesel is not that much more efficient.

They do not make more power, everything else being equal. Lots of torque, yes. Lots of horsepower, no.
Horsepower is torque X RPM.
Diesels require large heavy pistons and rods, as well as having a fuel that burns quite slowly. As such, they cannot do high RPM.
Your buddies motor is highly modified, yours is not.

Horsepower is what actually accelerates the car, torque does not, your transmission exists specifically to give torque over a broad range. A 100hp diesel vs a 100hp gasoline motor will do the 0-60 mand 1/4 mile in exactly the same time, despite the diesel having two or more times as much torque.

You're also comparing turbocharged motors to normally aspirated motors, that's like comparing a 4350 GPU to a core2duo.
If you took that same displacement gasoline engine and gave it the same amount of turbo boost as the dfiesel, it would eat the diesel for lunch.

[nd4spdbh2]

Originally Posted by Bobnova

They are somewhat more efficient, in the 35-40% range compared to 30-33% for gasoline. The 40% diesels are stationary motors that have a 300rpm window. Diesel is not that much more efficient.

They do not make more power, everything else being equal. Lots of torque, yes. Lots of horsepower, no.
Horsepower is torque X RPM.
Diesels require large heavy pistons and rods, as well as having a fuel that burns quite slowly. As such, they cannot do high RPM.
Your buddies motor is highly modified, yours is not.

Horsepower is what actually accelerates the car, torque does not, your transmission exists specifically to give torque over a broad range. A 100hp diesel vs a 100hp gasoline motor will do the 0-60 mand 1/4 mile in exactly the same time, despite the diesel having two or more times as much torque.

You're also comparing turbocharged motors to normally aspirated motors, that's like comparing a 4350 GPU to a core2duo.
If you took that same displacement gasoline engine and gave it the same amount of turbo boost as the dfiesel, it would eat the diesel for lunch.

Yes but you also have to take into consideration that you have a transmission effecting output.... a transmission on a diesel motor will be geared higher to make use of its torque and in the end create more where it matters.

And torque gets you off the line... hp keeps you going. But this is not my debate. What im trying to point out is that TDI's are the way to go... they produce very similar hp and way more torque... while using less fuel, which is easier to manufacture, and produce less emissions.

[Bobnova]

Still stink, still cost more for a given power output, and still cost more for a given mileage, too.

Torque gets you off the line indeed, but your transmission gives you as much torque as you need regardless of the motor.
A diesel transmission with long gears gives you good torque off the line.
A gasoline transmission with short gears gives you torque off the line.

I did take the transmission into account, if you'll re-read the above post.

The transmission does not create torque anywhere, either.

[Niku-Sama]

Originally Posted by Bobnova

No modern cars use flat heads (with the valves on the side). Only lawn mowers, and really very few of those. He mentions those just so he can say 40%.
.

what are you talking about, the guy has an OHC head on his bench, if you check the pics there are OHC and OHV heads that people have cut slots into

[nd4spdbh2]

as far as the original topic.... cutting notches into a head has been done but its not worth it.

[Bobnova]

The 40% number was from a "side valve" motor. That, to me, says flathead.

[doz]

Yeah, this wont work with modern engines. Its a joke really. That site is a joke.

Everyone is so worried about the environment, yet everyone continues to contribute. Im tired of this crap. If cars are so bad, ban them. Make it law that people ride bicycles or walk who have less than a 10 mile commute (no cars in other words). Atleast then itll solve 2 problems. Obese America and Polluting America. Hell, youll even gain revenue from ticketing all the people who try and get away with it

[Cowboy Shane]

What is really funny is that, in the information on Wikipedia about flathead or side-valve engines, the idea of having channels cut in the head has been done before:

The greatest advancements to flathead engine technology were developed in the 1920s through experimentation by Sir Harry Ricardo of Great Britain, who improved the performance and efficiency of flathead engines by intently studying their flow characteristics. He published his findings, and obtained patents, in 1927. Primarily, his Ricardo Head can be recognized on sight, because he moved the location of the exhaust valve farther from the center of the cylinder than the intake valve (they had previously been symmetrical). He also paid careful attention to the form of the intake and exhaust tracts cast into the cylinder block as regarded turbulence in the intake stream and within the combustion chamber.

Modern engines have complex head geometries that are unlikely to be improved by cutting channels...

[Cowboy Shane]

Originally Posted by doz

Yeah, this wont work with modern engines. Its a joke really. That site is a joke.

Everyone is so worried about the environment, yet everyone continues to contribute. Im tired of this crap. If cars are so bad, ban them. Make it law that people ride bicycles or walk who have less than a 10 mile commute (no cars in other words). Atleast then itll solve 2 problems. Obese America and Polluting America. Hell, youll even gain revenue from ticketing all the people who try and get away with it

That idea might have the unintended consequence of increasing urban sprawl and flight to suburbs. Most people would choose a home 11 miles from their work than anything from an eighth of a mile to 10 miles if it means they can drive rather than walk.