Those people who thought I was wrong about the 1jz and 2jz cranks....

[siman]

Remeber you guys talking about you "cannot have a stroked motor without having a longer crank stroke"....

Besides the point. The 1jz and 2jz are .5 LITERS different. The blocks are identicle except for just one thing. DECK HEIGHT. The 2jz has about a half (to 3/4) inch taller deck height compared to the 2jz

The cranks are the same. I have verified that from Orin B. Sr. off Supra Forums...the guy built both motors for competitive drag racing years back and even made the US's first 1.5jz.....He told me the cranks are IDENTICLE. The rods are the only part INTERNALLY that cannot be swapped.

ok. We all know from the FACTORY the 1jz had a equal torque to HP rating. 280ps and 280lb's of torque. Now at higher HP numbers that equality DECREASES on the torque's side. Just like F1 motors ( extreme example) they create somewhere in the realm of 800-900bhp, and ONLY 350-400lb's of torque...WHY? Becuase the INTERNALS are not heavy enough to carry the weight at lower rpms....


HENCE. The 2jz's superior torque ratings...the internals ( only the rod has changed) is heavier...giving the motor that little edge it needs to produce better torque values per HP increase.

That being said. The pistons, wrist pin placement and just say FOR NOW the cranks are identicle between the 2 motors.

The rods alone woule make up the increase in internal weight to give that extra kick of torque.

NOW. I was reading a August 2004 issue of Road and Track magazine.

You guys said that you could not increase displacement WITHOUT increasing crank stroke???? WRONG:

Page 48-49 of August 2004 issue of Road & Track CLEARLY STATES about the new 2005 Porsche 997 Carera and S model Carera:

" The current Carera 3.6- Liter engine is continued; the new Carrera S gets a 3.8- liter engine which the capacity increase is obtained by 99.0- mm ( instead of 96.0- mm ) cylinder bores, the stroke REMAINING at 86.0 mm.
There is a more rigid (nevertheless 400g lighter) crankshaft common to BOTH engines, but with a torsional damper added in the case of the 3.8."

My proof that you DO NOT NEED a crankshaft stroke increase to increase OVERALL displacement.

This in turn disproves ALL claims that Toyota used different cranks in the 1jz and 2jz blocks. The only difference is the rods. The taller/thicker/ more beefy rods of the 2jz....made to withstand more loads.....hence more power ( torque in this matter) can be obtained.

This is the exact reason toyota didnt revamp the block. They NEW they had a GREAT block and bottom end...but NOT enough torque for racing...getting out of hairpins at low speeds and high gears....

They had to increase the internal weight rather than develope a whole new size crank which would have to develope new rods and NEW PISTONS....changing the whole motor basically.


All toyota did was change the rods and increase the deck height to support the longer bigger rods.....thats IT.

Nobody has challenged me on this, ever since Orin told me the differences ( or similarities of that matter) between the two blocks. No one had CLEAR evidence of this or that being the case...it was all subjective and subject to name calling.

All i have heard is BS calling, name calling.

That stops RIGHT NOW. I have finally proven my point of increasing displacement without increasing crank stroke. All of this is relative to my argument about the cranks being the same...

Japanese have alternative ways of increasing the overall size of the motor....

Just like my old statement about the way the USED to originally measure displacement. The used to bring once cylinder to BDC and pour a liquid into the bore to measure how much CC's ( liters) it took to fill it, then times that amount by the number of cylinders and you have your displacement in liters.

The taller deck height of the 2jz would give it that extra much of "liquid" to fill in the extra MINISCULE amount of .5 liters....its not this huge big difference everyone thinks it is...rather is very small indeed. Go get a 2 liter bottle of coke and pour out 1/4 of it.....then devide it AGAIN by 6.....yeah now you get me.

-Jonathan Mann

 

[CTsupra]

probably one of the most informative posts i've read in a while. good job!

 

[Cz.]

Of course you can increase displacement by increasing the bore. Isn't that what a couple guys are doing? From flatlander or something?

 

[siman]

Nope, thats Oneandgone ( defiant7m...allan).....he got a custom crank and bored it out and such....very different...thats completly custome.

I am just showing that Toyota did NOT use different crank set ups for the 2jz....its the same darn thing.

People ( who should remain nameless) have kept on saying "you cannot change displacement without changing the crank stroke" yada yada blah blah blah...

well i finally got all my papers together and made my friggen point! I new i was right. I had that gut feeling. There was just "another way" of calculating the displacement of the motor.....another way to get that "number" without changing some parts in the motor...and its exactly what toyota did...and Porsche is doing, now.

-Jonathan

 

[IJ.]

I said it in the last debacle Siman you really need to learn and understand the basics of engine design you're 100% WRONG if you think the 1jz and 2jz cranks have the same stroke....

 

[siman]

I said it in the last debacle Siman you really need to learn and understand the basics of engine design you're 100% WRONG if you think the 1jz and 2jz cranks have the same stroke....

You, IJ, do not have ANY first hand experiance with either motor 1 on 1. Orin B. sr/jr both do. They know this. And its quite frankly not about if i know how the "basics of engine design" work, rather then i just found out how you GET the size of the motor by taking different measurements.

Of course for you, as a life long hot rodder, you have been tought the only way to make a BIGGER MOTOR was to stroke it out.....Thats the OLD ways of doing things.

There are easier ways to get HP and torque than just buying a custom crank and rods and pistons ( for wrist pin height placement)......of couse on that particular method you are using the ORIGINAL block with the ORIGINAL deck height.

It was just easier for toyota to make a new 1jz block casting just that much taller and call it the 2jz.....use the same crank, pistons ( revamp the head for the lost compression to raise it back up to 8.5:1) and make just bigger longer more stout rods.

Thats how they did it. Porsche is doing it.

Why cant YOU understand that?

-Jonathan

 

[IJ.]

Siman: Until YOU learn the formulas needed to calculate engine displacement and UNDERSTAND them you're talking through your arse on this!

I don't give a fuck what you've been told Engine basics are the same and have been since the first engine was built there are no "magic rods or magic deck heights" that change the laws of physics!

You're just making yourself look foolish by continuing this garbage.

 

[siman]

IJ,
there are no laws of physics on calculating of making up a new engine size.

Porsche didnt need physics to make a 3.6 to a 3.8 liter just by bore'ing the same block out.....the same rods, same crank....just different sized pistons..and they increased displacement my .2 liters....

imagine increasing deck height...overall height of the block.
There is alot more metal ( displacement ) added to the block when increasing that critcal part.

I am not re-writing the laws of calculating the displacement, rather than speaking of sneaky ways manufacturers are coming out with their ways of getting extra CC's or Ltr's of size out of the same blocks or same internals.


Its just mechanical trickory. And Japanese and Germans love doing those sort of things.

 

[siman]

Again,

No one has proven me wrong in saying the cranks are the same.

People just know what they HEAR. thats all.....all this BS, calling names and such....THATS GARBAGE, IJ.

I dont think anyone on here has taken the time and effort i have to actually verify this.

Orin B. and his son have. They spent years working on their mk3 with both motors and a 1.5Jz powerplant...they have looked at both internals side by side.

And still, people snub their noses at me while i preach the truth, its becuase what THEY have been tought on increasing displacement doesnt match what i am saying....

they are stubborn and unwilling to accept a different angle of attack on gaining displacement.

 

[Shawndude]

1JZ - I6 2492cc - 86.0 bore x 71.5mm stroke
2JZ - I6 2997cc - 86.0 bore x 86.0mm stroke
7M - I6 2954cc - 83.0 bore x 91.0mm stroke

Huh, Simman? You cannot create a "stroker" without increasing the "stroke" (obvious no?). You cannot increase the displacement, without increasing either the bore, stroke or number of cylinders.

Now you can juggle some aspects of engine design by the location of the connecting rod, but you will never change the displacement that way.

 

[siman]

Thats the point. NO ONE has called the 2jz a stroked motor. Not even TOYOTA themselves.

its just an egine with increased size....displacement....or LITERS....

Way back when i touched on that, everyone thought i was saying "the 2jz is a stroked motor"...when i was just trying to say where they got the extra .5 liters from when the cranks were identicle....

and it all went down hill becuase people just did not comprehend what i was trying to say.

All in all,

Toyota wanted more torque out of the 1jz. What they did was add internal girth to the motor.

1. They already had a awsome strong block.
2. They already had a awsome crank
3. They already had forged pistons ready to take a pounding.

What they didnt have was Torque ( in higher HP applications).
They needed some way to increase tq WITHOUT changing the crank stroke.

So they revised the block ( added height) to accomodate larger sized ( length and width) rods, these were just HEAVIER and had a LARGER mass to give the NEW motor the Extra kick at low RPM's that the 1jz didnt have ( at least it did at HIGH rpms, where tq is useless).

That is my point. That is what toyota did. The 2jz is NOT stroked. It was massaged and renamed.

 

[IJ.]

Because you are talking SHIT Jon and have no fucking idea.

I'm done bye......................

 

[siman]

Because you are talking SHIT Jon and have no fucking idea.

I'm done bye......................

read the highlighted section above your original post please.

 

[gixxer750]

Using longer rods with the same crank would equal the same displacement, even with a taller deck height. The pistons would come up higher at the top of the stroke, but they would also be an equal amount higher in the bore at the bottom of the stroke, therefore creating the exact same displacement. You would have to change the stroke of the crank or overbore to increase displacement.

 

[Shawndude]

1JZ - I6 2492cc - 86.0 bore x 71.5mm stroke
2JZ - I6 2997cc - 86.0 bore x 86.0mm stroke

Hmm, one is not like the other? How do you get the extra stroke without a different crank? Hint......you can't.

 

[IJ.]

OK here's what I propose Siman

You say the 1jz and 2jz cranks are identical no difference in any way shape or form for the length of stroke!

I'll fly to the States and buy a 1jz motor and a 2jz we'll strip them together ans compare the crank throws.

If you're correct you can keep both motors

If I'm correct YOU pay for everything my flight and accomodation included.

Time to stop talking shit and put your money where your mouth is.

For this to happen there will be a legal contract drawn up.

 

[ma71supraturbo]

(don't forget freight $$ for the 2 engines you'd want to take to the other side of the globe)

 

[Shawndude]

Shhh IJ, I was hoping to sell Siman some "magic pixie dust displacement enhancement connecting rods" for big bucks.

What man wouldn't want more virile connecting rods with superior length and girth?

<I need to update my spam filters>

 

[siman]

Grow up IJ, seriously.

Exactly Shawndude. You say what you hear.

The way that Toyota has measured the block itself is entirely different from the way the US manufacturers do it.

measure from the TC of the crank to the top of the deck, there is your 71.5 vs. 86mm stroke.

Again, has anyone but me PM'd orin on this ( from supra forums)????

You guys argue so hard, but wont ask the man....so lame.

-Jonathan

 

[IJ.]

Put up or shutup Siman I have the cash here and can come as soon as I sort a visa and the legal docs I'm 100% serious on this.