Come on guys were all family here(supra wise). Lets all calm down a bit. No need to get all angry over the subject.
1jz and 2jz bottem end.
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siman said:
discouraged?? nah don't be ignorant.. just putting you in your place like me and the good dr have done in the past....
why else would i post this in OFF TOPIC to begin with?
I love watching threads grow to 4 pages in 2 hours.....great stuff. :bigthumb:
EDIT: and my post count needs to friggin come up :rofl: :rofl: :rofl: :rofl:
I love watching threads grow to 4 pages in 2 hours.....great stuff. :bigthumb:
EDIT: and my post count needs to friggin come up :rofl: :rofl: :rofl: :rofl:
I<3Supras said:
sorry but when the posts get ignorant. It is time to shut the idiot down that is posting such stupidity. If he wants to be ignorant fine but don't be passing that ignorant shit as FACT because like me, Shawndude and IJ will tell you. We WILL set you striaght with FACT not hocus pokus mumbo jumbo. Except i will not sugar coat the ignorant posters stupidity. I will call you on it.
siman said:
hmmm
did you comprehend what reading is? Off topic huh.let see
Supramania > 86.5 - 92 MK3 Supra > General Discussions > 1jz and 2jz bottem end.
weird don't say nothing about off topic there.
I guess you will be getting a higher post count slick.... probably not in this forum.
Dumbass, if you noticed the first post ( from me) is a LINK to the thread in OT...thats all this was ment for. :ugh2:
but you and your little "cuss em' out, get em' out" gang decided to go apeshit over this topic.....
i guess you think its your time to shine???? whatever doo doo head. Everyone in there right automobilistic mind knows how to search on google.com much less search for " engine displacement".....
doo doo head.
but you and your little "cuss em' out, get em' out" gang decided to go apeshit over this topic.....
i guess you think its your time to shine???? whatever doo doo head. Everyone in there right automobilistic mind knows how to search on google.com much less search for " engine displacement".....
doo doo head.
No more negative reputation left to give
Somehow I picture Simann as a 48 year old laughing his ass off at all the controversy he stirs up by posting known fact as fiction
Somehow I picture Simann as a 48 year old laughing his ass off at all the controversy he stirs up by posting known fact as fiction
close the thread before anything else is said. Its pointless to argue any further about this since its pretty clear how people disagree with Siman. So i ask if a moderator or someone close this thread because its out of hand.
ma71supraturbo said:No more negative reputation left to give
Somehow I picture Simann as a 48 year old laughing his ass off at all the controversy he stirs up by posting known fact as fiction
:rofl: ....I wish....
While I know this thread is now closed, I simply want to add to this the fact that displacement is not the volume inside of an engine. A 3.0L engine does not have 3.0L in it, it has more than 3.0L. 3.0L is the displacement, in other words, it is the amount of fluid each cylinder can suck in, added together.
If each cylinder has a 0.5L displacement, that means that the volume in that cylinder at the bottom of the stroke is 0.5L more than what the volume is at the top of the stroke.
If you consider the formula for volume, you've got the area of the circle, multiplied by the height of the cylinder. Because the area above the piston at the top of it's stroke doesn't change (it gets added to the overall volume at both the top and bottom of the stroke), it doesn't affect displacement, so you can ignore it when calculating displacement.
The bore (area of the circle) and the stroke (height) of the "cylinder" are all that can affect displacement. As such the only real way to increase displacement is to either increase bore or increase stroke. The way Porsche did it was to increase the bore.
Your first post siman was in error, the only way to have a stroked motor is to change the crank, but it's not the only way to increase displacement. Changing bore can result in an increase in displacement, but it is not a stroked motor.
The bore of the 1JZ and 2JZ are both 86.0mm, simply leaving the only other way for there to be a difference in displacement the stroke, which is of course 71.5mm for the 1JZ and 86.0mm for the 2JZ. Stroke cannot be changed without changing the crank.
Here is a diagram to explain it better:
A: Total Cylinder Volume, Top of Stroke, 0.2L
C: Total Cylinder Volume, Bottom of Stroke, 0.7L
B: Displacement: 0.5L
As you can see, making the deck higher could not change the displacement, only the volume above the piston. Toyota needed more space to allow the piston 86.0mm to move up and down inside the block. The 1JZ piston only had to move up and down 71.5mm.
The space above the piston at the top of it's stroke is simply the area that the fluid sucked in during the down stroke gets compressed into. Hence, in my diagram, 0.7L is being compressed down into a space of only 0.2L.
This is how you can have 2 engines with exactly the same bore/stroke/block, etc, and yet one will have higher compression, the space is made to be smaller above the piston. This is why the Turbo pistons are dished on the 7M-GTE and not on the 7M-GE, to change the compression. Allowing more space above the piston. But note: it did NOT change the displacement.
Lower compression on a Turbo engine allows for more boost with less detonation, it also does something else though. Because of the lower compression, it actually means there is more volume to fill in the cylinder. Meaning you could fit more air into a lower compression engine than into a higher compression engine.
Whether or not you choose to believe what is and has always been one of the basic fundamentals of engines is up to you. If you want to believe Orin's 1 time statement that the 1JZ and 2JZ have the same crank, even though he has stated elsewhere that they are not the same, that also is up to you. In the end the choice is yours to be made. I thought about this exact issue about a year ago, and spent about 3-4 days thinking over how 2 engines with the same bore/stroke can have different compression ratios, but I did finally come to terms with the way things are. This is something you're going to do, or not going to do.
I'm going to finish off this post with the following; in order to fully understand, you need to understand what the word displacement means, it is the change in position, displacement is not a synonym for volume, they are 2 very different terms, and cannot be interchanged, even though they both use the same unit when referring to engines. The volume inside an engine is not the displacement of an engine. You need to realize that if you ever hope to understand the way things work. The 1JZ and 2JZ cranks are not, nor can they be the same with the difference in displacement. Not unless the 1JZ had a smaller bore, which it doesn't. The 1JZ's short stroke is one of it's strongest points with regards to it's purpose. It can rev like nothing else, because at 7000rpm, the piston is actually moving at a slower velocity than a 2JZ would be at 7000rpm. (The 2JZ piston has to move up and down 86.0mm, while the 1JZ piston only moves up and down 71.5mm in the same amount of time).
Good luck as you continue to research this further, and I suggest you send off an email to Orin Sr if you would like some more clarity from him.
I hope this message finds you well, and I hope you take it as it was written.
If each cylinder has a 0.5L displacement, that means that the volume in that cylinder at the bottom of the stroke is 0.5L more than what the volume is at the top of the stroke.
If you consider the formula for volume, you've got the area of the circle, multiplied by the height of the cylinder. Because the area above the piston at the top of it's stroke doesn't change (it gets added to the overall volume at both the top and bottom of the stroke), it doesn't affect displacement, so you can ignore it when calculating displacement.
The bore (area of the circle) and the stroke (height) of the "cylinder" are all that can affect displacement. As such the only real way to increase displacement is to either increase bore or increase stroke. The way Porsche did it was to increase the bore.
Your first post siman was in error, the only way to have a stroked motor is to change the crank, but it's not the only way to increase displacement. Changing bore can result in an increase in displacement, but it is not a stroked motor.
The bore of the 1JZ and 2JZ are both 86.0mm, simply leaving the only other way for there to be a difference in displacement the stroke, which is of course 71.5mm for the 1JZ and 86.0mm for the 2JZ. Stroke cannot be changed without changing the crank.
Here is a diagram to explain it better:
A: Total Cylinder Volume, Top of Stroke, 0.2L
C: Total Cylinder Volume, Bottom of Stroke, 0.7L
B: Displacement: 0.5L
As you can see, making the deck higher could not change the displacement, only the volume above the piston. Toyota needed more space to allow the piston 86.0mm to move up and down inside the block. The 1JZ piston only had to move up and down 71.5mm.
The space above the piston at the top of it's stroke is simply the area that the fluid sucked in during the down stroke gets compressed into. Hence, in my diagram, 0.7L is being compressed down into a space of only 0.2L.
This is how you can have 2 engines with exactly the same bore/stroke/block, etc, and yet one will have higher compression, the space is made to be smaller above the piston. This is why the Turbo pistons are dished on the 7M-GTE and not on the 7M-GE, to change the compression. Allowing more space above the piston. But note: it did NOT change the displacement.
Lower compression on a Turbo engine allows for more boost with less detonation, it also does something else though. Because of the lower compression, it actually means there is more volume to fill in the cylinder. Meaning you could fit more air into a lower compression engine than into a higher compression engine.
Whether or not you choose to believe what is and has always been one of the basic fundamentals of engines is up to you. If you want to believe Orin's 1 time statement that the 1JZ and 2JZ have the same crank, even though he has stated elsewhere that they are not the same, that also is up to you. In the end the choice is yours to be made. I thought about this exact issue about a year ago, and spent about 3-4 days thinking over how 2 engines with the same bore/stroke can have different compression ratios, but I did finally come to terms with the way things are. This is something you're going to do, or not going to do.
I'm going to finish off this post with the following; in order to fully understand, you need to understand what the word displacement means, it is the change in position, displacement is not a synonym for volume, they are 2 very different terms, and cannot be interchanged, even though they both use the same unit when referring to engines. The volume inside an engine is not the displacement of an engine. You need to realize that if you ever hope to understand the way things work. The 1JZ and 2JZ cranks are not, nor can they be the same with the difference in displacement. Not unless the 1JZ had a smaller bore, which it doesn't. The 1JZ's short stroke is one of it's strongest points with regards to it's purpose. It can rev like nothing else, because at 7000rpm, the piston is actually moving at a slower velocity than a 2JZ would be at 7000rpm. (The 2JZ piston has to move up and down 86.0mm, while the 1JZ piston only moves up and down 71.5mm in the same amount of time).
Good luck as you continue to research this further, and I suggest you send off an email to Orin Sr if you would like some more clarity from him.
I hope this message finds you well, and I hope you take it as it was written.
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