Open Animal build help

If you have the 6580 or the 6580 C - ARC crank makes a difference.
I only use the 6580 crank. In fact the 6580 C is no longer available.
 
I am assuming that you are talking about a flathead crank in the animal??? Some will some won't . you won't know until it blows. IF you had a new heat treated flathead crank. I would use it. but I haven't seen one in a long time. I have a couple but they are used. Don't know their history?
 
We have a few heat treated flathead cranks, but I wouldn't use them in an open. I'd rather run the stock cast flathead cranks than the HT's ones.
Get the billet ARC and be done with it. The last thing you want to do is blow up an engine that you sunk a bunch of time and money into.

The stock forged animal crank will maintain 9K no problem (so far.)


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🏁Thanks and God bless,
Brian Carlson
Carlson Racing Engines
Vector Cutz
www.CarlsonMotorsports.com
Carlson Motorsports on Facebook
31 years of service to the karting industry
Linden, IN
765-339-4407
bcarlson@CarlsonMotorsports.com
 
We have a few heat treated flathead cranks, but I wouldn't use them in an open. I'd rather run the stock cast flathead cranks than the HT's ones.
Get the billet ARC and be done with it. The last thing you want to do is blow up an engine that you sunk a bunch of time and money into.

The stock forged animal crank will maintain 9K no problem (so far.)


-----
🏁Thanks and God bless,
Brian Carlson
Carlson Racing Engines
Vector Cutz
www.CarlsonMotorsports.com
Carlson Motorsports on Facebook
31 years of service to the karting industry
Linden, IN
765-339-4407
bcarlson@CarlsonMotorsports.com
Do the animals need 3rd or 4th bearing supports like the clone arc cranks to keep from ending up in two pieces?
 
Not questioning your recommendations, but I have always wondered what the stock crank is good for and how long. Can they really hold up at 8.5-9K no problem? Would this very build benefit from ratio rockers being relatively low lift to begin with? I have been looking at buying a used WKA animal (they are stupid cheap, nothing to lose) and throwing some drop in parts. Just never knew how much I can get away with before having to go to the FH stroker crank and really dropping money on the head/valve train.
A stock Briggs crankshaft will break at 10,200 RPMs... don’t ask me how I know this !!! Lol
 
I have turned Stock animals cranks to over 9000. no problems. I have The flathead cranks to over 9000 no problem. But the flathead crank in an animal if under much more pressure. especially a used crank, and there are to my knowledge any new raptor cranks! Could be, but just not to my knowledge. I agree with Brian Carlson! ARC billet crank is the way to go. A modified animal or open Animal will produce a lot of hp! Like I said before, I have really good flathead cranks and lunati crank, But I put ARC cranks in both of my Animals. Really nice pieces. And yes an open or modified animal will turn 9,000 in a heartbeat and keep on pulling strong. depending on the cam and the rest of the build.
I have had engines (not animals) come apart at 9000 plus. Not much left to salvage. Not much at all. And yes Flatop1 Dustpan needed to pick up all the pieces.
 

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That's where the usually break.
Whew, Good for you!
Fortunately, the piston didn't smack the valves and destroy the head.
 
That's where the usually break.
Whew, Good for you!
Fortunately, the piston didn't smack the valves and destroy the head.
The block, piston and rod appeared to have no visible damage, not even the bearing boss on the block looked damaged, but I replaced the entire short block and upgraded to the billet crank, sold the engine for pennies on the dollar a few months ago, those stroker animals are a ticking time bomb... Jimbo do you feel that the billet cranks are worth the $$ upgrade over the Briggs cranks, some have told me that they also will break..
 
I won't build a stroker without one but then I rarely build a small one.
I build a lot of 3" or bigger model 15"s and would never consider using a OEM Briggs flathead crank in one.
If it's done right they run well for a long time.
No offense to anyone but Some people can find a way to break anything.
In my opinion turning them at 10,000 is asking for trouble and there is no HP there!!
 
What spark plugs are good to run in an open animal? Is there a better plug than the auto lite 3910x? Also, what are the recommend torque specs for head studs I can’t find them anywhere.
 
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