Eagle 3.58" cast crank, who's broke 'em ?

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skrews

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Like the title says who's broke 'em ? Plenty of horror stories about the 4" stroke cranks breaking, but I don't recall seeing anyone mention breaking a 3.58 stroke crank.
 
Like the title says who's broke 'em ? Plenty of horror stories about the 4" stroke cranks breaking, but I don't recall seeing anyone mention breaking a 3.58 stroke crank.


Is it an Eagle crank?
 
running a stock stroke 3.310'' Stroke 340 crank cast eagle ... kinda worried about what people are saying about it.. but my motor puts out 440hp no problems so for been in the car since may rev limiter in it bounced it at 5500 rmp would love to port my heads and put bigger cam in it but now i am worried ..
 
Never broke a 4", but was leery enough to sto pusing them. I've got two 4" ones in use - between 450-480hp on both, one going on 9 years in service and 20K on it. I'd think as long as it's internally balanced and the mains are align honed(all engines I do are) you should be fine for anything under 500hp. That's just my opinion tho. I haven't heard of any 3.58s breaking but they may also be a service replacement rather than "performance" part.
 
Before the aftermarket crankshafts hit the market the ladies and men of Mopar ran power adders to the STOCK cast iron 360 crankshafts-lots of power.

A debate continues about whether some of the aftermarket steel or iron cranks are as reliable as the old STOCK cast iron cranks. MRL has pointed out in one of my previous posts that the SCAT STEEL crank should be stronger.

Fair warning: my knowledge is second hand, aka keyboard commando...
 
I broke the 4" cast eagle. It was line honed, properly balanced and in the 490 HP range. It let go with approx 3000 relatively easy miles in my 4 SPD car on a particularly harsh 1-2 power shift. Spend the extra cash and buy a forged crank. It is well worth it. I cannot cment on the smaller stroker cranks.
 
4'' scat cast cranck for the last 3 or 4 years
no problem so far
engine pushing close to 600 hp
internally balance:prayer:
rev to 7100 true the trap on the 1/4:eek:ops:
do alote of burn out out the street

and if it come apart :violent2:the only thing left to do
is building a stronger one :D
 
I have heard of cast cranks breaking when people run a two step and stay up on it for a long time or run a high rpm leave chip which shocks the crank real hard. Just my 2 cents but I have never broken one myself.
 
Any reason why not to use a stock OEM 360 crank?...should be able to get a crank kit from machine shop...

I have been beating on stock cast 360 cranks with 2 steps for 20+ years and have never broke one...So now you have heard that they dont break..
 
Any reason why not to use a stock OEM 360 crank?...should be able to get a crank kit from machine shop...

I have been beating on stock cast 360 cranks with 2 steps for 20+ years and have never broke one...So now you have heard that they dont break..

X2 I have never broke a stock crank.
Been hard on them for over 30 years, spin a rod or break a piston once in a while.
 
Our iron head 360 bottom end started its performance life in a dirt modified. We put it in the Duster just to play with it, and ended up buying it from a friend. We beat on it off and on for years and at the last freshen discovered a crack, so now it has a forged crank.
 
Already have the crank from a previous build. Thought I'd put it back in use if no one had a story about breaking one. Going into a budget/dumpster build anyway, so if it chits the bed oh well.
 
Here in Brazil We had three issue involving this Eagle 4.00 Cast Crank on speed shop that I worked. All three crack in the same place!

We don't had any issues with SCAT.
 
had a few snap on dirt tracks street stock engines with 10"tires ,making 350 hp with a 500 holly 2 barrel they don't like to spin then hit a nice tacky track. The stock cranks out of trucks were stronger.
 
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