Will I break this crank?

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Rat Bastid said:
If it were only that simple. Of course, crank balancing is incredibly important. But if you’ve seen how far the balance can be and not break anything you’d have a different opinion.

The crank is constantly twisting and untwisting. The damper is there to absorb those forces.

That’s why I said I wouldn’t do a cast crank 4 inch stroke on 340 mains. There isn’t enough overlap. When there isn’t enough overlap, the crank fails. Or, the crank is so thick through overlap that you needless added weigh when the better option was a steel crank.
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That makes sense about the damper. I'll make sure to get a good one. Thanks
 
I just want to mention the blown stock internal cast crank 440 on uncle Tony's garage.
I have no opinions with exception that I've beat the crap out of every 5.2 5.9 magnum I've ever had, drag racing my Dakota's. Not that any ever seen high rpm but I can say I've never broke a cast crank. Would I prefer a forged crank yes.
 
I'm doing the same thing with my 408. 475 to 500hp and a 100 shot. I have a controller so I can ramp it in. I researched it a lot. Many sbc and sbf claiming running 300 shots on the scat 9000 cranks without a problem. Some going over 700 hp. Some big blocks over 800. I think a mopar crank should be stronger because of more overlap. I figure the crank is stronger than the stock block.
 
aaronk785 said:
I'm doing the same thing with my 408. 475 to 500hp and a 100 shot. I have a controller so I can ramp it in. I researched it a lot. Many sbc and sbf claiming running 300 shots on the scat 9000 cranks without a problem. Some going over 700 hp. Some big blocks over 800. I think a mopar crank should be stronger because of more overlap. I figure the crank is stronger than the stock block.
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Cool, I'm going to take my chances with the scat cast 9000. I think I read the journals and mains on the mopar cranks are bigger than the sbc. That can only help.
 
Light weight parts, a good balance job, a good damper, and big ring gaps. You’ll be fine at that power level.
 
Lurch59 said:
It's not a matter of affording it. I just don't like wasting money. If it's unlikely I'll break the crank, I'll chance it. It's like my lug nut analogy. You don't want your wheel coming off, so why not use 10 studs per wheel. Because 5 studs have worked well. Why spend money that you don't have to?
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frankly, that thinking usually will end up getting in your wallet more.
475 horse plus spray…forged….just do it right the first time
 
Lurch59 said:
It's not a matter of affording it. I just don't like wasting money. If it's unlikely I'll break the crank, I'll chance it. It's like my lug nut analogy. You don't want your wheel coming off, so why not use 10 studs per wheel. Because 5 studs have worked well. Why spend money that you don't have to?
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Agreed, I don't like wasting money either...and more than likely you will be fine at your power level....but when you look at the cost of your engine AND trans, what's another couple hundred bucks on a $8,000 - $10,000 set up (just guessing on price)? I mention the trans because if the crank lets go it will probably hurt the trans too.....but, to each their own. If you are comfortable with the risk then hammer down my friend :).
 
flyfish said:
Agreed, I don't like wasting money either...and more than likely you will be fine at your power level....but when you look at the cost of your engine AND trans, what's another couple hundred bucks on a $8,000 - $10,000 set up (just guessing on price)? I mention the trans because if the crank lets go it will probably hurt the trans too.....but, to each their own. If you are comfortable with the risk then hammer down my friend :).
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Well, I have the Scat 9000 crank. So now I have to sell that one and buy a forged crank, so it's not a couple of hundred unless I find a buyer. I guess my question should be, has anyone broke this crank at 600 hp? So far, no one here tells me they have. And I totally agree, you might be right!
 
I knew we would reach a consensus. Now. let's talk about whether the election was stolen and was there another shooter on the grassy knoll........?:poke:
 
Your Scat 9000 stroke crank will work fine with your build. They would not sell those if they were going to twist like a pretzel.

Where you are going to run into trouble is when you start giving it the shot of NOS. Daily Cruiser and Once in a While take a run at the Track.
That NOS is going to turn up any shortfalls of any type of engine you build.

360 Crank.jpg

Got to stop and think what you are really going to use it for. Apply common sense as needed. You will be fine.
 
I have a stock stroke Scat 9000 360 "Internal Balance" cast crank sitting on the shelf back at the shop. Wonder if your Scat 9000 Stroker crank is built as an internal balance also. Or if it has to be external balance because of the stroke clearances of the block.

All about the design of the build and getting the proper balancer and proper flex plate or flywheel to work with type of balancing you are needing for your build.
 
I'm just going to say this:
for every 500 times i have heard of a crank braking, 499 of then were cast Eagle Cranks. That "one" is just about any other crank out there.

Take all the advice about protecting that stroker crank.......
My self i have a forged everything, 13:1 compression motor that i only twist to a whopping 5800 rpm
 
I’m guessing that early production cast 4.000 cranks had issues?

Cranks do break, even very expensive steel billet etc.

There is probably a flaw in the casting technique with them cheaper Chinese jobbies.

But if you break a forged or billet crank it’s some sort of vibration that has weakened the steel.
High rpm’s with an out of balance scenario.
 
Cudafever said:
I'm just going to say this:
for every 500 times i have heard of a crank braking, 499 of then were cast Eagle Cranks. That "one" is just about any other crank out there.

Take all the advice about protecting that stroker crank.......
My self i have a forged everything, 13:1 compression motor that i only twist to a whopping 5800 rpm
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Have you broke the 12 second barrier yet... LOL...:poke:...
 
Your cast crank will be fine ..
Don't let the people who bought forged for a peace of mind get into yours...
 
The cost between a cast and forged crank is much less if you internally balance the cast crank (they should be internally balanced). Otherwise you have to live with external balancing and I won’t get into how bad that is. But it’s a bad idea. Just like removing the center counterweights. It was not because it was a good idea, but it’s because it made the bean counters happy.
 
Also if your truly only using a 125 shot I don't think you'll need extra large ring gap's..
 
It's a little hard to estimate the horsepower at my 3200' elevation. I'm planning on 10.5 to 1, and looking at cams now. We only have 91 Octane premium. It is easy to find ethanol free premium though. There is a 10 percent horsepower penalty at this elevation, and I am not willing to mix race gas with premium. I suppose 10.5 to 1 is more like 9.5 to one at this elevation. If I shoot for 600 hp it's likely I'll only be making 540.
 
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j par said:
Your cast crank will be fine ..
Don't let the people who bought forged for a peace of mind get into yours...
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I'm not hearing too many stories of broken Scat 9000 cranks. Mostly worries about cast cranks.
 
j par said:
Have you broke the 12 second barrier yet... LOL...:poke:...
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Why yes i have 11.87........
With all the money you spent on your Psssss Pssss set up..... have you sprayed it down the track yet?
Its been like, two years now, hasnt it:poke:.
 
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