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still chuggin' along
1981 Corolla SR5
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Discussion Starter · #1 ·
I've heard about bored and stroked engines, but I don't know what that means. Can anyone give me a definition?
 

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Platinum Shift Customs
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to 'bore' an engine you increase the diameter of the cylinder and to 'stroke' an engine you change the length of the connecting rod to play with the length of the stroke

simple explination but i hope this was what you are looking for

Jeff
 

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1994 Toyota Camry
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Hatch said:
to 'bore' an engine you increase the diameter of the cylinder and to 'stroke' an engine you change the length of the connecting rod to play with the length of the stroke

simple explination but i hope this was what you are looking for

Jeff
And what does that accomplish?
 

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Grenaded piston
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Hatch said:
to 'bore' an engine you increase the diameter of the cylinder and to 'stroke' an engine you change the length of the connecting rod to play with the length of the stroke
Correct on bore.

Wrong about stroke. Stroke is related to the crank.

Lets say you shorten or lengthen the rod, but keep the crank the same. All your doing is moving the piston up or down and changing the compression ratio, stroke stays the same.
 

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Platinum Shift Customs
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Yes sorry my bad however when you do stroke an engine you will still have to adjust the connecting rod :)
 

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Trailer Trash Engineer
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.tony. .riot. said:
And what does that accomplish?
Going up on bore or stroke gives you more displacement, which is the same as making your engine bigger. Stroking emphasizes torque, and boring tends to emphasize HP. Generally, anyway.
 

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Man, stroking is fun. I'm doing it right now! wait! j/k:D






88LE, you do need adjusted rods when you stroke your engine. Along with drilling to allow for the stroked crank to fit properly, and many other factors that don't seem important to mention in this format:)
 

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Grenaded piston
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^ I know. I'm not a noob when it comes to engines. ;)

All I was saying is that, if you keep the crank the same and change the length of the rods, the stroke stays the same.

In other words the crank determines the amount of stroke.
 

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88 LE said:
^ I know. I'm not a noob when it comes to engines. ;)

All I was saying is that, if you keep the crank the same and change the length of the rods, the stroke stays the same.

In other words the crank determines the amount of stroke.
:D I know your not.

I just needed a moment of having self-esteem. But you had to go and wreck that didn't you?:(
 

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Grenaded piston
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SmokingTiresV6 said:
I just needed a moment of having self-esteem. But you had to go and wreck that didn't you?:(
Nah....

If it makes you feel any better, go skool some noobs in the Camry section. Thats what I do. ;)
 

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88 LE said:
Nah....

If it makes you feel any better, go skool some noobs in the Camry section. Thats what I do. ;)
But you always get there first! I work 3pm to 2am. I'm not home in time to have any of the real fun. Eh, I guess. But it gets old schoolin' people on intakes.

We need to ban that word from the forum:D
 

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Mighty~Mart said:
but why would a person bore the throttle body?
You bore the throttle body to allow more air/fuel mixture into the engine.


homeguard said:
smaller strokes = higher rpm but less torque right?
Nope. RPM stays the same. You may be able to push it a little more, but I wouldn't do it.

88LE might no more about the RPM change...

As for torque, you gain torque by stroking over your engine. Which is the reason muscle cars do it so often. It brings some major low-end gains.
 

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96 3MZ M/T
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homeguard said:
smaller strokes = higher rpm but less torque right?
rpm's are controlled more by the cams and springs, really good titaninum springs and cams grinded down right can let you hit higher rpm's, also how the head was built determins part of that, computer and also type (rotary compleatly diffrent system)
 

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^
Well, it's not just how strong the parts are. It's their design. Valve trains have to be designed for high RPM. Most of the time you can't really change your engines redline. Because that is how the engine was designed.
 

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Grenaded piston
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SmokingTiresV6 said:
Nope. RPM stays the same. You may be able to push it a little more, but I wouldn't do it.

88LE might no more about the RPM change...
The rod to stroke ratio has little to do with it.

Its mostly the design of the head, cams, etc...

As for torque, you gain torque by stroking over your engine. Which is the reason muscle cars do it so often. It brings some major low-end gains.
Yup.

My buddy Steve has a 351 bored (.060 over) and stroked to 7.1 L. ;)

http://www.crankflex.com/pix/cars/67 Mustang/67 mustang engine (434W).JPG
 

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88 LE said:
The rod to stroke ratio has little to do with it.

Its mostly the design of the head, cams, etc...



Yup.

My buddy Steve has a 351 bored (.060 over) and stroked to 7.1 L. ;)

http://www.crankflex.com/pix/cars/67 Mustang/67 mustang engine (434W).JPG
*Drooling*

MMMM... Mustang 7.1L:eek: Wow. That is sweet.

I have always liked 305s a little more. Cause you can bore and stroke them, and then put 351 heads on to let it breath.

Your friend Steve should get a Merlin intake manifold for it. They put down some crazy power:cool:
 

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Grenaded piston
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SmokingTiresV6 said:
I have always liked 305s a little more. Cause you can bore and stroke them, and then put 351 heads on to let it breath.
305? Did you mean to say 302?

Your friend Steve should get a Merlin intake manifold for it. They put down some crazy power:cool:
The 67 is sitting around collecting dust till he decides what to do with it.

As for the intake, nah. Thats what the supercharged 89 is for. ~650hp w/14 psi boost. :thumbsup:

http://www.crankflex.com/pix/cars/89 Mustang

http://www.imagestation.com/album/?id=4289215413
 

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