How far can I rev on a stroker block?

[64_Frankenstein]

With the 4G64 crank onto a 4G63 block I was wondering how far or high can the motor rev? According to the gallant 100mm crankshaft their red line sets at 6 grand?

 

[dSmgs-T]

anywhere from 75-8500 depending on how good your valve train is.

 

[64_Frankenstein]

anywhere from 75-8500 depending on how good your valve train is.

Thanks. I upgrade the valve train.

 

[mitsu_matt]

Put it on a dyno, chances are your not going to make any/much power past 7500.

 

[TunaTalon]

The correct answer to your "it depends". The weight of rods and pistons are handy for calculating maximum acceleration forces. However weight is a weak indication of strength. For a given weight forged steel rods are stronger than cast and Aluminum and Titanium rods are stronger than steel. For any material and weight of rod the shape will affect yield strength in compression and tension.

Not to mention:
Bearing material: Tri-metal bearings will have higher loading limits than Aluminum.
Piston skirt height: Shorter skirts are lighter but longer are more stable.
Strength of the crankshaft and its bracing: That meat in the bottom end has a reason to be.
Intake valve area: Max usable RPM can also be limited by air flow.
Cam timing: Higher RPMs have different optimal cams than moderate RPMs.
Wrist pin location: Higher pin locations are more stable than stock locations.
Design boost: Higher boost brings higher compression loading on the internals.
Bore diameter: Friction losses increase with the square of the bore but displacement and weight increase with the cube of the bore.

That is not all but should make the point. There are many variables in the physics that determine optimal rev limit. Beyond the physics there are just as many subjective judgments in engine design.

How much do you want to spend on this engine?
How often are you willing to rebuild the engine?
If the engine blows will you lose a race or your life?
How important is low end torque?
Does your income depend on this being the best engine on the track?
Do you want to waste time on... (No wait that's me)?

Sorry but complex value judgments just can't be reduced to a single number (well except for the movie 10.)

For more on strokers and max RPM, please see http://www.kidzuku.com/StrokeOrNot.pdf.

 

[skatershawn]

Im sure that the crank and lower end can handle quite a bit if built well!
Now the thing i would be most worried about when revving high would be the head and all the valves and lifters.. etc.

 

[64_Frankenstein]

Put it on a dyno, chances are your not going to make any/much power past 7500.

I figure. That make sense.

 

[Rob10_99]

"Stroke or not" that pdf will give you any information on stroker/destroke or any of that bs you should ever want to know besides head flow.
The most important part IMO on rev'ing a stroker is the piston speed, that determines the longevity/reliability of your build.
I don't see many strokers, I don't see many strokers rev'in to 10k like a build 2L.

 

[64_Frankenstein]

The correct answer to your “it depends”. The weight of rods and pistons are handy for calculating maximum acceleration forces. However weight is a weak indication of strength. For a given weight forged steel rods are stronger than cast and Aluminum and Titanium rods are stronger than steel. For any material and weight of rod the shape will affect yield strength in compression and tension.

Not to mention:
Bearing material: Tri-metal bearings will have higher loading limits than Aluminum.
Piston skirt height: Shorter skirts are lighter but longer are more stable.
Strength of the crankshaft and its bracing: That meat in the bottom end has a reason to be.
Intake valve area: Max usable RPM can also be limited by air flow.
Cam timing: Higher RPMs have different optimal cams than moderate RPMs.
Wrist pin location: Higher pin locations are more stable than stock locations.
Design boost: Higher boost brings higher compression loading on the internals.
Bore diameter: Friction losses increase with the square of the bore but displacement and weight increase with the cube of the bore.

That is not all but should make the point. There are many variables in the physics that determine optimal rev limit. Beyond the physics there are just as many subjective judgments in engine design.

How much do you want to spend on this engine?
How often are you willing to rebuild the engine?
If the engine blows will you lose a race or your life?
How important is low end torque?
Does your income depend on this being the best engine on the track?
Do you want to waste time on… (No wait that’s me)?

Sorry but complex value judgments just can’t be reduced to a single number (well except for the movie 10.)

For more on strokers and max RPM, please see http://www.kidzuku.com/StrokeOrNot.pdf.

40 over stroke JE pistons, Eagle rods, 100MM knife crankshaft, and balance shaft remove. That's what I done so far to the bottom block. I don't drive my DSM on the streets anymore because it had retire so in that case I wont be rebuilding as much maybe once in a year depending how many time I visit the track.

Im always into stroker and yes it's worth the time and already invest alot of money into it so why stop? I already know most of these information but thanks anyway.

How much do you want to spend on this engine?
More then I can afford

How often are you willing to rebuild the engine?
Depends because I don't drive it

If the engine blows will you lose a race or your life?
I don't see how you can lose a life in a race but of course lose a race I can understand that

How important is low end torque?
Very important

Does your income depend on this being the best engine on the track?
Of course

Do you want to waste time on… (No wait that’s me)?
I don't call it a waste of time. I sure do wope a lot of ass on the road with it so it's worth it.

 

[64_Frankenstein]

"Stroke or not" that pdf will give you any information on stroker/destroke or any of that bs you should ever want to know besides head flow.
The most important part IMO on rev'ing a stroker is the piston speed, that determines the longevity/reliability of your build.
I don't see many strokers, I don't see many strokers rev'in to 10k like a build 2L.

Thanks. I don't seen or heard either.

 

[64_Frankenstein]

Im sure that the crank and lower end can handle quite a bit if built well!
Now the thing i would be most worried about when revving high would be the head and all the valves and lifters.. etc.

Well Im not too worrying about the bottom block from not handling the mass abuse because I already beef it up. Im just worrying about If I rev more then it require will it destroy the piston. Because it got me thinking that since the JE stroker piston are shorter then the original piston Im scared that the piston skirt might break or crack at 7000 RPM+. I just want to know if anyone have that problem before. I don't think I'll be reving too high so Im not too worry about it and I've already upgrade the valve train.

 

[64_Frankenstein]

Thanks for the advice people! This thread may rest in peace.

 

[my4ATEurV8]

lets assume that your head can handle any rpm you throw at it. now what you also want to take into your calculation as well is what your rod/stroke ratio will be when you build your block. a higher rod/stroke ratio is better for higher revs. one way to achieve this is to use a longer rod than normal, and put the wrist pin on the piston higher. i believe the standard rod for a g464 crank is 150mm, giving you a rod/stroke ratio of 1.5:1. i know you can get them for that crank up to 156mm maybe even longer, this would give you a ratio of 1.56:1 allowing you to rev higher/safer! now lets forget about your head for a moment and focus on just your rotating assembly. think of engine a, and engine b. both are 2.4 liters with a 100mm crank. engine a has standard 150mm rods and engine b has 156mm rods. if you rev them both to 7500 for a long period of time in identica l conditions then take them apart. you would find that engine a has much more wear on the cylinder wall and is beginning to take on an oval shape. you would find that engine B has far less cylinder wear because of the higher rod/stroke ratio.
so the higher the ratio you have, the less of an angle your rod will have when it goes up and down in the cylinder as your crank rotates resulting in less stress on your piston and cylinder wall. you will have less of a chance of breaking a rod as well.



i hope that helps you. so if i was going to use a factory 100mm 4g64 crank with lets say the eagle/wiesco combo. i would probably only rev to around 7000 at most if on the 150mm rods. i know people have gone higher with that, but how do their cylinders and pistons like going that high.
im using a full magnus 2.4 long rod assembly. (magnus 100mm crank, magnus 156mm rods, and magnus 9:1 pistons) ill be reving to 7750 for street driving and 8500 at the track

 

[64_Frankenstein]

lets assume that your head can handle any rpm you throw at it. now what you also want to take into your calculation as well is what your rod/stroke ratio will be when you build your block. a higher rod/stroke ratio is better for higher revs. one way to achieve this is to use a longer rod than normal, and put the wrist pin on the piston higher. i believe the standard rod for a g464 crank is 150mm, giving you a rod/stroke ratio of 1.5:1. i know you can get them for that crank up to 156mm maybe even longer, this would give you a ratio of 1.56:1 allowing you to rev higher/safer! now lets forget about your head for a moment and focus on just your rotating assembly. think of engine a, and engine b. both are 2.4 liters with a 100mm crank. engine a has standard 150mm rods and engine b has 156mm rods. if you rev them both to 7500 for a long period of time in identica l conditions then take them apart. you would find that engine a has much more wear on the cylinder wall and is beginning to take on an oval shape. you would find that engine B has far less cylinder wear because of the higher rod/stroke ratio.
so the higher the ratio you have, the less of an angle your rod will have when it goes up and down in the cylinder as your crank rotates resulting in less stress on your piston and cylinder wall. you will have less of a chance of breaking a rod as well.



i hope that helps you. so if i was going to use a factory 100mm 4g64 crank with lets say the eagle/wiesco combo. i would probably only rev to around 7000 at most if on the 150mm rods. i know people have gone higher with that, but how do their cylinders and pistons like going that high.
im using a full magnus 2.4 long rod assembly. (magnus 100mm crank, magnus 156mm rods, and magnus 9:1 pistons) ill be reving to 7750 for street driving and 8500 at the track

Thanks. You're information is useful. I have stander size Eagle rods. When my stroke JE piston arrive it got me thinking that it will some how will wear the piston skirts and the cylinder wall because the piston is a lot shorter than the stander size piston. Well I don't drive it anymore unless I take it to the track. I might go with the 4G64 block in the near future to ovoid rebuilding.

 

[caliboy23]

I called Road Race Engineering recently to ask them about going with the 2.4 vs. the 2.3. They said that there have been way too many head gasket issues with the 2.4 option. As a matter of fact, Mike told me to "Take the idea of the 2.4 and throw it out the window." The 2.3 will make just as much power with WAY less headaches. And since I don't see a lot of shop cars using the 2.4 option, I have to assume there's some validity to that.

 

[my4ATEurV8]

a 4g63 block is more readily available than a 4g64/g4cs. it takes more work to make a 4g63 into a 2.4 stroker than it is to just drop in parts and make it a 2.3 because of clearance issues, i believe.
i asked pete at magnus about that whole head-gasket thing when i ordered my 2.4 setup from them. he told me that its not a problem as long as u are using the right head gasket, just the same as any other motor.
shops will also tell you not to go with a 2.4 because they cant handel hi rpm's..... that goes back to my post about rod/stroke ratio's. but then again a 2.4 will spool a large turbo around 500 rpms sooner than a comparible 2.0 will and give you crap tones more usable tq. you should also think about piston speed, because your piston is moving a shit ton faster on a 2.4 doing 7500-8500 than it is on a 2.0 at the same rpm. so it all depends on how you want to build your motor because at the end of the day, its still your name on the title( hopefully ).

 

[caliboy23]

That's what so many people don't seem to understand about turbo motors. I constantly have to remind local friends of mine, that if you rev to 10 and the turbo falls off at 6 your wasting your time and hurting the motor. That's why dyno tuning is important. Even to newbies. I would much rather have an 8,000 RPM limit with a 2.3 than a 10,000 RPM limit with 2.0. Simply because if your doing things correctly your not gunna buzz the motor to the moon after your turbo stops making power. Plus the 2.3 / 2.4 has a much more usable power band for the street. And if that 2.4 crank is the Butcher crank or an Eagle with no balance shafts and a Fidanza flywheel,......... Forget about it.

 

[AshTsi]

if that 2.4 crank is the Butcher crank or an Eagle with no balance shafts and a Fidanza flywheel,......... Forget about it.

Can you expand a bit more on this?

 

[lccynmbr13]

I rev my 2.3 with eagle acrank and rods with wisecos to 8k. Motor didn't last very long though either. With my ball bearing to4z on this next build I'm hoping to be able to shift at 7500 and still land in the fat range of my powerband. You want to spool a fat turbo on a daily driver build a stroker. You want a safely high revved racecar that lags like a bi*** on the street build a 2.0 Sheps 2.0 for a reason.

 

[donniekak]

That's what so many people don't seem to understand about turbo motors. I constantly have to remind local friends of mine, that if you rev to 10 and the turbo falls off at 6 your wasting your time and hurting the motor. That's why dyno tuning is important. Even to newbies. I would much rather have an 8,000 RPM limit with a 2.3 than a 10,000 RPM limit with 2.0. Simply because if your doing things correctly your not gunna buzz the motor to the moon after your turbo stops making power. Plus the 2.3 / 2.4 has a much more usable power band for the street. And if that 2.4 crank is the Butcher crank or an Eagle with no balance shafts and a Fidanza flywheel,......... Forget about it.

The solution is to use a turbo that can flow enough for a 10,000 rpm 2.0. I would rather have 2,000 rpm's more rev on top than 500 rpm's faster spool any day. Horsepower is a function of rpm, and torque. The same amout of torque 2,000 rpm's higher in the rev range is about 35% more horsepower. If anyone doubts this reasoning, why do all of the fastest 4g63's run a 2.0?
strokers are good for the street, but how many are 1,000 hp +?

 

[420a-t]

The solution is to use a turbo that can flow enough for a 10,000 rpm 2.0. I would rather have 2,000 rpm's more rev on top than 500 rpm's faster spool any day. Horsepower is a function of rpm, and torque. The same amout of torque 2,000 rpm's higher in the rev range is about 35% more horsepower. If anyone doubts this reasoning, why do all of the fastest 4g63's run a 2.0?
strokers are good for the street, but how many are 1,000 hp +?

Kiggly has a 2.3

 

[MidShipCivic]

I called Road Race Engineering recently to ask them about going with the 2.4 vs. the 2.3. They said that there have been way too many head gasket issues with the 2.4 option. As a matter of fact, Mike told me to "Take the idea of the 2.4 and throw it out the window." The 2.3 will make just as much power with WAY less headaches. And since I don't see a lot of shop cars using the 2.4 option, I have to assume there's some validity to that.

Empty claims with little explanation that's so fulfilling.

An oem car with an oem rev limit you're tuning and building for more power throw that out the window please.

 

[1fastlaser]

Kiggly has a 2.3

2.3/ 8.4s at over 165mph....easily 1000hp.

So many people worry about "how high can I revv this setup".

Its not how high you can revv it, its were you make power to. Just because you can revv a motor to 9k plus, dosent mean your going to be making efficent power there. Revving high just puts more wear on parts regardless if your 2.0, 2.3, or 2.4....but if you make power there then go for it.

The stock valve train, with cams (hks 272s) had been 8500 easily with no problems for years on end back in the day. Your typical cam setup with valve springs will handle the higher revvs. Its once you get into the wild cams you gotta worry about the more serious situations.

 

[donniekak]

Kiggly has a 2.3

Exactly my point, who else? The 2.0 has been 6's. I'm not bashing strokers. Many people have problems keeping them together at high revs. Strokers are very good, up to a point. After a certain point a 2.0 actually has a wider powerband, just higher. When you have a turbo capable of really big power, sure you spool 5-700 rpm's sooner. But, you rev limit is 2500 rpm's lower/ what the stroker really does is make more torque, the enemy of the dsm trans. If you are looking for a 6-700 hp monster a stroker is killer. To run 200mph in the quarter you need the revs of the 2.0.

 

[420a-t]

My reasoning to turn people to the stroker is because it's tons more fun to drive. 99.9 perceent of people won't be in the 6's, or go 200mph. Why run something that isn't as much fun to drive, because the fastest people run 2.0's? That doesn't make sense to me.

If you balance everything correctly, you can go higher than 9k on a stroker.

I understand where you're coming from, but I wanted people to see the other side too, ya know?

My reasoning to turn people to the stroker is because it's tons more fun to drive. 99.9 perceent of people won't be in the 6's, or go 200mph. Why run something that isn't as much fun to drive, because the fastest people run 2.0's? That doesn't make sense to me.

If you balance everything correctly, you can go higher than 9k on a stroker.

I understand where you're coming from, but I wanted people to see the other side too, ya know?