Aces High Bulletin Board
General Forums => The O' Club => Topic started by: Beefcake on November 15, 2008, 09:53:22 AM
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....and it cost me 39 dollars. :) I could get used to gas being $1.84/gal, just as long as we don't lose sight of the overall energy problem. So how's your gas? Is it bad?
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1.96$ here. Was nice to fill the Scion for only 20.72$ a few days ago instead of 27$. :D
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22 gallons would cost you $150 over here in Blighty. :cry
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Filled my Car up this morning before heading into work, Cost me $2.58 per Gallon for Premium (San Francisco area) For a while there it was setting me back about $4.86 a gallon for Premium :O
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Filled my Car up this morning before heading into work, Cost me $2.58 per Gallon for Premium (San Francisco area) For a while there it was setting me back about $4.86 a gallon for Premium :O
What do you drive? What is the compression ratio of your engine?
I'm asking simply because I find that most people who use high octane gas don't know that they are probably decreasing the engine performance.
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Still $2.13 here in Tucson, sigh.
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....and it cost me 39 dollars. :) I could get used to gas being $1.84/gal, just as long as we don't lose sight of the overall energy problem. So how's your gas? Is it bad?
1.85 in front of my shop. 8 miles south it's 1.81.
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What do you drive? What is the compression ratio of your engine?
I'm asking simply because I find that most people who use high octane gas don't know that they are probably decreasing the engine performance.
and most cars these days(with a few exceptions) are designed to run on 87 octane.
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and most cars these days(with a few exceptions) are designed to run on 87 octane.
Correct, that is because most engines have roughly an 8-1 compression ratio. The only reason to run higher octane gas is if you have a high compression engine. If you run high octane gas in a normal compression engine, not only are you wasting your money on more expensive gas, your actual gas mileage will probably suffer a bit too.
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In western NY we generally have the highest gas prices in the continental USofA. Only places regularly higher are Alaska and Hawaii.
Needless to say I visit the reservation every other fill up, tax free.
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What do you drive? What is the compression ratio of your engine?
I'm asking simply because I find that most people who use high octane gas don't know that they are probably decreasing the engine performance.
I drive an 07 BMW 335i Coupe six speed, inline 6 cylinder 300 or 350 BHP (can't remember which) with twin turbos, one Turbo does 3 cylinders, Don't know the compression ratio!
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Since gas started going insane I limited myself to $50 a week unless I had some serious traveling to do for work.
Anything else, instead of hopping in my work to run to the store. or to pick my daughter up from someplace vehicle I used my wifes 4 cylinder.
I've seen it go as low as less them half a tank. Now I can almost fill it.
I've seen gas here as low as $1.90
Though its probably lower now. As I've been sick the last few days and havent driven much.
Falling gas prices are the only thing we have going for us now.
Can you imagine what it would be like in this economy if gas were still near $4.00?
I dont even wanna think about it.
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I have a 4 dr 2005 2500HD Silverado, when gas was $4.25 a gallon the thing sat and i used my company car. Filling it was $100.00. I would only use it to run things to the back of my property, then park it. I called it my $33,000 wheelbarrow.
Gas prices are wonderful now. The thing actually sees the road now, and i park the company car. :aok
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$1.71 here in Northern Ohio. In response to the premium thing, our Land Rover get a few miles per gallon better mileage on premium, enough to make it worthwhile. Runs better too. Although it still only gets like 14 miles per gallon :cry :cry
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$3.79 for regular unleaded here :aok
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around 2.30 up here(northern NY ft.Drum area)
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$1.77 at the Kroger in Huber Heights (Dayton) Ohio.
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$1.77 at the Kroger in Huber Heights (Dayton) Ohio.
Jeez, wouldn't mind those prices round here! :O
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I drive an 07 BMW 335i Coupe six speed, inline 6 cylinder 300 or 350 BHP (can't remember which) with twin turbos, one Turbo does 3 cylinders, Don't know the compression ratio!
Nice car! You have 300 hp and 300 ftpounds of torque FYI. Also you have about a 10.2 to 1 compression ratio, which is pretty high, so your car is one of the few that actually benefits from high octane.
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paid $1.68 by airport the other day. sad though cause avgas is still $4.30
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In western NY we generally have the highest gas prices in the continental USofA. Only places regularly higher are Alaska and Hawaii.
Needless to say I visit the reservation every other fill up, tax free.
Avg here $2.58 from: http://www.buffalogasprices.com/
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$1.73 down at the pac-a-sac west texas
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It's as low as $1.85 around the metro areas here. Out in the sticks where I live it's still $2.20. Did I mention there is a refinery here? It's cheaper to buy gas 100 miles away from the plant than it is next door to it.
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Wow, we pay by the liter over here, so that makes premium $6.32 per gallon, and $6.10 for regular and that's at the decreased prices of today. Here I was thinking phew back to $90.00 a fill except for when I want to get a bit more go out of the beasty and use premium which is about $95.00 a tank. At the peak of the price increase I was up to $130.00 per fill.
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....and it cost me 39 dollars. :) I could get used to gas being $1.84/gal, just as long as we don't lose sight of the overall energy problem. So how's your gas? Is it bad?
Well, it's been announced that we AREN'T going to do any more offshore drilling...no Alaska, new coal-fired power plants will be a regulatory impossibility....as soon as world economies get back in gear (year or 2, likely) we will be exactly where we were last July. (Unless one thinks 'green' technology is ready to run the United States)
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there you go with the negative vibes again, think positive, think of windmill farms everywhere, acres of solar cells, all paid for by the rich people.
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Wow, we pay by the liter over here, so that makes premium $6.32 per gallon, and $6.10 for regular and that's at the decreased prices of today. Here I was thinking phew back to $90.00 a fill except for when I want to get a bit more go out of the beasty and use premium which is about $95.00 a tank. At the peak of the price increase I was up to $130.00 per fill.
Yeah but you can drive from one to the other end of your counrty on 1 tank full..lol. I have to drive an hour just to get to a city of any size. And there is NO PUBLIC transportation where I live. There arn't even any taxis...I was like 13-14 before I ever saw a taxi for the first time other than TV.
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Yeah but you can drive from one to the other end of your counrty on 1 tank full..lol. I have to drive an hour just to get to a city of any size. And there is NO PUBLIC transportation where I live. There arn't even any taxis...I was like 13-14 before I ever saw a taxi for the first time other than TV.
I pay that in Australia. Try doing my country on one tank.
Wow, we pay by the liter over here, so that makes premium $6.32 per gallon, and $6.10 for regular and that's at the decreased prices of today. Here I was thinking phew back to $90.00 a fill except for when I want to get a bit more go out of the beasty and use premium which is about $95.00 a tank. At the peak of the price increase I was up to $130.00 per fill.
Amen, Tongs.
When you yanks start paying $6 a gallon, feel free to complain.
Actually.... no, don't, I pay over $6 a gallon to run my car and I never complain about fuel.
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2.16 gal in NW Oregon
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$1.68 a gallon this morning, QT Bixby, Ok.
It's nice to have pocket change fill your car again.
:aok
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Nearly 8 dollars in Europe :mad: :mad:
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I drove thru town today and it had dropped to $1.79/gal. Man I got ripped off.
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The last time gas was this cheap I hadn't had my driver's license for long! :)
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was $1.73 this morning in St Louis area :O :aok
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$6.84 / gallon boy it's cheap again. Was closer to 8 before.
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I can still remember buying gas for 18 cents a gallon....... :cry
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$2.35 in The San Fransisco Bay area
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$2.25 in Vegas.
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$1.71, way south Texas.
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In 1986 I remember paying $1 for a gallon of gas and $1 for a pack of Marlboughros
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somethin like 2.20 in south western massachusetts, depending on were you are. that was 2 or 3 days ago, not sure now
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In 1986 I remember paying $1 for a gallon of gas and $1 for a pack of Marlboughros
i started driving in 1979. 89 octane leaded regular was 89 cents. 93 octane super unleaded was around .99 or 1.01 or so.
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Nearly 8 dollars in Europe :mad: :mad:
So far BarryBD is the only one who has a free pass to complain about fuel prices.
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gas hasnt been this cheap since right after I started driving lol. If it stays like this till summer, new camaro here i come
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Correct, that is because most engines have roughly an 8-1 compression ratio. The only reason to run higher octane gas is if you have a high compression engine. If you run high octane gas in a normal compression engine, not only are you wasting your money on more expensive gas, your actual gas mileage will probably suffer a bit too.
Many turbocharged cars will run higher compression ratios and require premium. Also, many European models require it as in Europe - what qualifies for 'premium' in the US is equivalent to the lowest octane fuel generally available (91 R+M/2 - 95 RON).
My wife's Volkswagen has a 2.0 Turbo I4 used by many Volkswagen / Audi models. It requires premium.
I'm curious as to why mileage will suffer in a car tuned for regular, but running premium? I agree there's not necessarily going to be any benefit, but I can't see why there would be any detriment either. I would think it goes like this:
Two cars - 1 tuned for 87, the other tuned for 91 are filled up with regular. The engine management module in the 87 car detects no knocking so runs as normal and produces its maximum power. The 91 car detects some knocking so retards the ignition a bit to compensate and suffers a loss of maximum power.
Next, both cars are filled with premium. The engine management module in the 87 car detects no knocking so runs as normal. The engine management module in the 91 car also detects no knocking and so runs as normal and develops its maximum power.
So while there's no advantage to using premium in the 87 car, I don't see where the disadvantage comes from (other than wasted money). That said, the holes in my mechanical knowledge have been cruelly exposed on this board before. :D
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The higher the octane rating the higher the flash point of the gas. So for an engine tuned for 87 running on 91 the fuel wont burn as efficiently because the engine doesn't run hot enough
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$2.15 east of mesa arizona :rock
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Many turbocharged cars will run higher compression ratios and require premium. Also, many European models require it as in Europe - what qualifies for 'premium' in the US is equivalent to the lowest octane fuel generally available (91 R+M/2 - 95 RON).
My wife's Volkswagen has a 2.0 Turbo I4 used by many Volkswagen / Audi models. It requires premium.
I'm curious as to why mileage will suffer in a car tuned for regular, but running premium? I agree there's not necessarily going to be any benefit, but I can't see why there would be any detriment either. I would think it goes like this:
Two cars - 1 tuned for 87, the other tuned for 91 are filled up with regular. The engine management module in the 87 car detects no knocking so runs as normal and produces its maximum power. The 91 car detects some knocking so retards the ignition a bit to compensate and suffers a loss of maximum power.
Next, both cars are filled with premium. The engine management module in the 87 car detects no knocking so runs as normal. The engine management module in the 91 car also detects no knocking and so runs as normal and develops its maximum power.
So while there's no advantage to using premium in the 87 car, I don't see where the disadvantage comes from (other than wasted money). That said, the holes in my mechanical knowledge have been cruelly exposed on this board before. Big Grin
The higher the octane rating the higher the flash point of the gas. So for an engine tuned for 87 running on 91 the fuel wont burn as efficiently because the engine doesn't run hot enough
Its actually more about the compression. The engine tuned for 87 simply does not have enough compression to burn all of the high octane fuel, therefor some of the fuel is being wasted. I think in many situations this would result in less fuel economy, less performance, or both.
Wooley, as far as I can tell the cars you mentioned have high compression motors (anything over about a 10 to 1 is high). In which case I would assume high octane is recommended by the manufacture.
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Many turbocharged cars will run higher compression ratios and require premium. Also, many European models require it as in Europe - what qualifies for 'premium' in the US is equivalent to the lowest octane fuel generally available (91 R+M/2 - 95 RON).not higher compression ratios.......but rather higher compression pressures. there is a difference/.
My wife's Volkswagen has a 2.0 Turbo I4 used by many Volkswagen / Audi models. It requires premium.
I'm curious as to why mileage will suffer in a car tuned for regular, but running premium? I agree there's not necessarily going to be any benefit, but I can't see why there would be any detriment either. I would think it goes like this:it won't actually suffer per se, but it will not benifit from the higher octane rating.
Two cars - 1 tuned for 87, the other tuned for 91 are filled up with regular. The engine management module in the 87 car detects no knocking so runs as normal and produces its maximum power. The 91 car detects some knocking so retards the ignition a bit to compensate and suffers a loss of maximum power.
Next, both cars are filled with premium. The engine management module in the 87 car detects no knocking so runs as normal. The engine management module in the 91 car also detects no knocking and so runs as normal and develops its maximum power.
So while there's no advantage to using premium in the 87 car, I don't see where the disadvantage comes from (other than wasted money). That said, the holes in my mechanical knowledge have been cruelly exposed on this board before. :D
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Its actually more about the compression. The engine tuned for 87 simply does not have enough compression to burn all of the high octane fuel, therefor some of the fuel is being wasted. I think in many situations this would result in less fuel economy, less performance, or both.
Wooley, as far as I can tell the cars you mentioned have high compression motors (anything over about a 10 to 1 is high). In which case I would assume high octane is recommended by the manufacture.
turbocharged cars run LOW compression ratios. this is due to the boost of the turbo. taqke a car with 10.5 to 1 comprsession ratio, and boost it. most likely, you'll pop the head gasket. in extreme cases, even stretch the head bolts enough to literall lift the head off the block.
run 8 to 1, and boost it. now you're running a higher compression pressure, but not blowing the gaskets out.
compression pressure is determined by the cam timing, lift, and any power adders.
compression ratio is determined by the size and shape of the combustion chamber, and the size and shape of the piston top.
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turbocharged cars run LOW compression ratios. this is due to the boost of the turbo. taqke a car with 10.5 to 1 comprsession ratio, and boost it. most likely, you'll pop the head gasket. in extreme cases, even stretch the head bolts enough to literall lift the head off the block.
run 8 to 1, and boost it. now you're running a higher compression pressure, but not blowing the gaskets out.
compression pressure is determined by the cam timing, lift, and any power adders.
compression ratio is determined by the size and shape of the combustion chamber, and the size and shape of the piston top.
One correction, compression ratio is also determined by cam timing and lift. In other words if the piston moves further up in the cylinder, you'll have a higher compression ratio.
Yes I left out the part about turbos and supers for simplicity, although once everything is said and done it is still the final compression (however you may achieve that) that determines what octane gas will work best.
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One correction, compression ratio is also determined by cam timing and lift. In other words if the piston moves further up in the cylinder, you'll have a higher compression ratio.
Yes I left out the part about turbos and supers for simplicity, although once everything is said and done it is still the final compression (however you may achieve that) that determines what octane gas will work best.
nonono../....
cam timeing and lift will change your compression pressure only.
you can take a 10 to 1 engine, and change the pressure according to the cam you put in. the only way to change the compression ratio is by changing the pistons, or the cylinder heads.
i put an X303 cam in my 5.0L. with all of that duration, and added lift, my compression ratio remained the same(9.5 to 1 i think), although my compression pressure changed drastically over the stock cam.
and, yes.....that final statement is definitly true......
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In a normal piston engine the compression ratio is the ratio between the volume of the combustion chamber when the piston is at the bottom of its stroke, and the volume of the combustion chamber when the piston is at the top of its stroke.
If you install a cam with more lift, the piston will move further on each stroke, and the volume of the combustion chamber when the piston is at the top of the stroke will be less, while the volume of the combustion chamber when the piston is at the bottom stays the same, resulting in an increased compression ratio.
If you say your compression pressure increased, then in effect so did your compression ratio since it is only a measure of the difference between the uncompressed and compressed combustion chamber.
Correct me if I'm wrong but I don't think I am on this one.
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In a normal piston engine the compression ratio is the ratio between the volume of the combustion chamber when the piston is at the bottom of its stroke, and the volume of the combustion chamber when the piston is at the top of its stroke.
If you install a cam with more lift, the piston will move further on each stroke, and the volume of the combustion chamber when the piston is at the top of the stroke will be less, while the volume of the combustion chamber when the piston is at the bottom stays the same, resulting in an increased compression ratio.
If you say your compression pressure increased, then in effect so did your compression ratio since it is only a measure of the difference between the uncompressed and compressed combustion chamber.
Correct me if I'm wrong but I don't think I am on this one.
Cams adjust valve timing, not the distance the piston travels per stroke.
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Bahh sorry I was using cams in the place of crankshafts. DUH! Sorry I haven't even thought about this stuff in years.
So if you change the CRANKSHAFT to increase the piston travel it will increase compression ratio. Everything else I agree on.
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CAP1 already stated how to change the compression ratio, change the pistons or change the heads.
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CAP1 already stated how to change the compression ratio, change the pistons or change the heads.
OR by changing the crankshaft, which was what I was originally trying to say (but with the wrong terminology). "Stroker" motors have different crankshafts which move the piston further, essentially increasing displacement but also increasing compression ratio.
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In a normal piston engine the compression ratio is the ratio between the volume of the combustion chamber when the piston is at the bottom of its stroke, and the volume of the combustion chamber when the piston is at the top of its stroke.
If you install a cam with more lift, the piston will move further on each stroke, and the volume of the combustion chamber when the piston is at the top of the stroke will be less, while the volume of the combustion chamber when the piston is at the bottom stays the same, resulting in an increased compression ratio. negative. the piston only travels the same distance, regardless of camshaft. the stroke on a 302(5.0L ford) is 3.00 inches, with a 4 inch bore. the old 289 ford engines(predecessor to the 302)was 2.87 inch stroke with 4 inch bore. the camshft cannot change this. the camshaft controls when, for how long, and how much the valves open. nothing more. this is how the camshaft changes compression pressure too. different cam profiles open at different places inrelationship to TDC.
1985 and Later 302 Roller Cam 1.60 5° BTC 39° ABC 49° BBC 5° BTC 286° 286° .339 I .542 I 107° 117°
224° 224° .339 E .542 E
these are X303 cam specs. you can see a ton of duration, and overlap. this'll hurt combustion pressure a bit at idle, but once ya wind her up............ :D :D
If you say your compression pressure increased, then in effect so did your compression ratio since it is only a measure of the difference between the uncompressed and compressed combustion chamber.
Correct me if I'm wrong but I don't think I am on this one.
In a piston engine it is the ratio between the volume of the cylinder and combustion chamber when the piston is at the bottom of its stroke, and the volume of the combustion chamber when the piston is at the top of its stroke.
now, so ya don't misunderstand me, i'm NOT trying to berate you in anyway.........just having a fun discussion with ya sir!!
i love this crap.....could talk bout it all day!
<<S>>
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Hog, I knew what you were trying to say. My last comment came out wrong, please ignore it.
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OR by changing the crankshaft, which was what I was originally trying to say (but with the wrong terminology). "Stroker" motors have different crankshafts which move the piston further, essentially increasing displacement but also increasing compression ratio.
BUT.......
you can change the crank, and not affect the compression either. it also can be determined by the pin depth in the piston, the klength of the connecting rod, the stroke of the crank throws too. :D
there was some weirdness with the late 60's ford 302's. some had shorter connecting rods than others did, but they had the same compression ratio. i'll try to find that one.....
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Ok so my original point is compression ratio can be changed by changing pistons, head OR by changing the crankshaft in certain situations, in which case I think we are all agreeing.
The problem started when I misused the term camshaft in place for crankshaft, obviously they are different and I know this, I just haven't talked car talk in so long it came out wrong.
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Ok so my original point is compression ratio can be changed by changing pistons, head OR by changing the crankshaft in certain situations, in which case I think we are all agreeing.
The problem started when I misused the term camshaft in place for crankshaft, obviously they are different and I know this, I just haven't talked car talk in so long it came out wrong.
in all seriousness......do you know how many times my parts supplier has sent me a cam sensor when i've ordered a crank sensor? and vice versa too? :rofl
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Fuzeman where you from? Growing up in Canandaigua I always experienced ridiculous prices too...I would see national averages and cry a little. If I was down in Elmira visiting family, it was cheaper being close to the PA border...
Anyway, I didn't even bring my car to DC with me...so I honestly don't know the price. There aren't too many gas stations in the heart of the city where I live/work.