Cast vs. Forged Crank?

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doogievlg

doogievlg

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I am starting to put together a list of pieces for my stroker build. I have decided to go with either a Scat or Ohio Crank assembly but my question is which crank to go with. The goal is around 475 hp on the engine and possibly later down the road a 200 shot. The car will be about 70% street 30% track time so I will be revving this motor quite high a few times a year at least. I had planned to go with a forged crank just for the peace of mind and to know I would not have to go back into it again. Now I am starting to question if it is really necessary. What are your opinions?
 
I think if you are going to race it and rev it high, go with forged. If it is a street engine, I think cast would do just fine.
 
There's been a few threads recently about scat cranks in the stroker kits, pertaining to balancing. The consensus seems to be that if you are going to internally balance your assembly, you might as well go with the forged crank as by the time you balance a cast crank and add Mallory the price comes out pretty close.

I went with the scat internal balance cast crank stroker kit and my engine builder said it was good to go but another member here had to add Mallory to the crank to get his to balance.
 
DO NOT use an Eagle cast crank. It will break.

Im sure you are like most and plan to do a 475hp motor, but you will likely want more, so just go ahead and do the forged the first time.
 
clv22p said:
DO NOT use an Eagle cast crank. It will break.

Im sure you are like most and plan to do a 475hp motor, but you will likely want more, so just go ahead and do the forged the first time.
Click to expand...

Didn't plan on using Eagle. They have an awful reputation an have done nothing to fix it.
 
With the cost of forged pieces you might as well go that route to start with.
 
It looks like Scat sells an internally balanced forged kit for about $1800. Would I be better off going internally or externally balanced?
 
I vote for forged due the HP and the % of time at the track.

Not sure it makes enough difference to worry over at all..... external balance puts a tad of extra stress on the crank ends. But if you had new external parts already, then at your HP level, I'd go external and not think twice about it.

Buying the assembly already balanced from SCAT makes a LOT of sense to me.
 
nm9stheham said:
I vote for forged due the HP and the % of time at the track.

Not sure it makes enough difference to worry over at all..... external balance puts a tad of extra stress on the crank ends. But if you had new external parts already, then at your HP level, I'd go external and not think twice about it.

Buying the assembly already balanced from SCAT makes a LOT of sense to me.
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I agree with this except having it balanced by the manufacturer. I've had to rebalance several cranks that were supposedly balanced. The first one got deep into my pocket because the customer said it was good to go and I didn't even check it. It shook like a dog pooping peach seeds. So I got to do the work again. I never take anyone's word on anything. I don't thing any good builder would. The customer is never happy to pay twice.

Have a good local shop at least check it. But then you pay twice.
 
So internally balanced but have them doubl check it at the shop. Also I will need to purchase a new flex plate since the one I have now is for externally balanced factory small block stuff correct?
 
Yes, plus the damper needs to be for internal balance (neutral balance damper). You can't mix internal balance cranks and external balance flexplate OR damper.

Well..... you CAN mix them but the results won't be nice. "....like a dog pooping peach seeds..." to quote a famous person LOL
 
Stock crank, SB cast is good to around 500 horsepower, BB 600.
Aftermarket? I would not trust any of them in anything but a grocery getter.
Go forged
 
doogievlg said:
I am starting to put together a list of pieces for my stroker build. I have decided to go with either a Scat or Ohio Crank assembly but my question is which crank to go with. The goal is around 475 hp on the engine and possibly later down the road a 200 shot. The car will be about 70% street 30% track time so I will be revving this motor quite high a few times a year at least. I had planned to go with a forged crank just for the peace of mind and to know I would not have to go back into it again. Now I am starting to question if it is really necessary. What are your opinions?
Click to expand...

I don't know if I read you right, but if money is a problem, you may want to rethink your plans.
IMHO from what I know, Strokers are more fast revving than high revving.
Sure you can do it, and tear them up!
And you can install an expensive 200 shot system,
and tear it up!
I'm sure Edgewater won't let you race without a rollcage if you're around mid 11's or faster.
More money, and now you have more of a race car than Street.
I take it, that this engine is a replacement for the one that just self destructed. Did you find out what went wrong?
Just my 2 cents. Hope this helps.





From
 
70 DUSTER CRATE said:
I don't know if I read you right, but if money is a problem, you may want to rethink your plans.
IMHO from what I know, Strokers are more fast revving than high revving.
Sure you can do it, and tear them up!
And you can install an expensive 200 shot system,
and tear it up!
I'm sure Edgewater won't let you race without a rollcage if you're around mid 11's or faster.
More money, and now you have more of a race car than Street.
I take it, that this engine is a replacement for the one that just self destructed. Did you find out what went wrong?
Just my 2 cents. Hope this helps.





From
Click to expand...

I haven't found out the cause but I'm just trying to put together a plan right now. I'm at a point where I have a decent job and I'm single with very little bills. If there is a time in my life where I can afford to build the engine I want then now is that time.

As far as Edgewater goes, I don't give Dick anymore of my money but I will make the necessary adjustments or I will back off it enough to slow me down if things get that fast wherever I am.
 
nm9stheham said:
That is pretty crappy indeed. Were these SCAT cranks or others? Just wondering if there are particular mfrs who don't do good work.
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One was a SCAT deal. I forget who the rest were. Sometimes it's a matter of standards. One shop in my area does street engines to under 10 grams and race engines to under 5 grams. We did 5 and 1 and tried to keep both ends within a gram.

There were some cranks that came through that were more than 20 grams off. If I have to stand behind it, it has to be to my standards.

Edit: the worse crank that came through was by a local shop. It was a 360 external balance. The pulley end was off by 8 grams and the flywheel end was off a 100. The guy who did the original job said I lied. I told him to come have a look. He didn't. Funny enough, it didn't shake after it was fixed. We all make mistakes. I just don't want to pay for others bad days. I have enough on my own!
 
doogievlg said:
I haven't found out the cause but I'm just trying to put together a plan right now. I'm at a point where I have a decent job and I'm single with very little bills. If there is a time in my life where I can afford to build the engine I want then now is that time.

As far as Edgewater goes, I don't give Dick anymore of my money but I will make the necessary adjustments or I will back off it enough to slow me down if things get that fast wherever I am.
Click to expand...

I agree! Now's the time.
I wish I would have approached it like that. I regret that I didn't. Get a good plan and Good Luck to you!
Kil-Kare is further away, but you might want to try it sometime, or just visit.
 
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70 DUSTER CRATE said:
I agree! Now's the time.
I wish I would have approached it like that. I regret that I didn't. Get a good plan and Good Luck to you!
Kil-Kare is further away, but you might want to try it sometime, or just visit.
Click to expand...

Kil-Kare is a much nicer facility and I have been a hand full of times. I am starting to become fond of Thornhill and Mountain Park Dragway all the way down in Clay City.
 
70 DUSTER CRATE said:
I agree! Now's the time.
I wish I would have approached it like that. I regret that I didn't. Get a good plan and Good Luck to you!
Kil-Kare is further away, but you might want to try it sometime, or just visit.
Click to expand...

I just figured why spend the money on a forged piece if I really didnt need it. Sounds like it would be a good idea though
 
Your just pushing the limits or years of experience, and a good hook-up in drag racing puts even more stress on things. Seems like a good investment in your case..... I have gone cast in the past but the engines were at lower limits.
 
nm9stheham said:
Your just pushing the limits or years of experience, and a good hook-up in drag racing puts even more stress on things. Seems like a good investment in your case..... I have gone cast in the past but the engines were at lower limits.
Click to expand...

With what little research I have done I would think cast stuff is safe to mid 400 hp range.
 
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