If cylinder temps in the duramax cause broken cranks, then every built motor out there would be having issues
Cranks
- Thread starter Fingers
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One of my friends built engine LBZ's broke the crank with less than 1000 miles on the build. Bet I know where it broke 
Kevin Cameron of Cycle World once wrote an article on the evolution of connecting rods. The gist of the article was that a hollow rod would be the best, for strength in all directions and being light at the same time. The rods couldn't be hollow because of the stress risers produced in the machining process would cause the rod to fail.
Looking at the latest round of pics, could there be some hidden stress riser in that hole designed to lower the weight of the throw?
Looking at the latest round of pics, could there be some hidden stress riser in that hole designed to lower the weight of the throw?
And those extra two bolts are a big deal when it comes to distributing the clamping force.
However, for truly advanced main cap design, you have to look at those with combined caps and girdle like this.
Thought a lot about making one for the Duramax.
We looked into this about two years ago but found the bottom structural integrity of the block after making necessary machining to the block was just something we did not feel comfortable with.
Even with our Girdle design we did we felt at the end of the day it was not going to gain any strength to the bottom end. Which is why we do not use a girdle on any of our builds. Until we see a reason our short block program from parts of choice and machining process will remain the same. Not one single crank, Main bearing failure, Rod, or block failure, Only failure we have scene is from damaged pistons burned up or cracked. That is all range of HP setups and applications.
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On the Chevelle..., We lost #5 piston with two major events left of the season. When we tore the motor down #4 main bearing was flattened on one half of the bearing, to the point of being squished around the main. The other half of the bearing showed major side loading. We decided to chance it for the last two events and put it back together with new parts. It made it four passes before cracking #1 piston. When tore down, #4 main bearing looked tore up exactly the same as before with only four passes. The motor made 100+ passes this season above 90psi. If anybody wants to test a fatigued crank pre break, I can send this one out.
Stock everything other then Carrillos, std ARP head studs, Cut LB7 pistons.
Stock everything other then Carrillos, std ARP head studs, Cut LB7 pistons.
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People say that aftermarket balancers help because it gets weight off the front of the crank, when Fingers actually found out more weight on the front may be better.
I have stock everything on my crank. no internal balance, no aftermarket flywheel, no aftermarket balancer, I didn't see the need to with all these cranks failing no matter what they have on them, except the alter fire cam.
In my opinion, and that is about all its worth, the alt fire is the best solution at this time.
I do believe that as we "fix" a weak point, we just go and find the next one. With the reduction in rod, then piston, then crank issues, the next issue coming up IMO is going to be the bearings and such. And IMO, the combined cap-girdle is a good solution for the flex down low.
I do believe that as we "fix" a weak point, we just go and find the next one. With the reduction in rod, then piston, then crank issues, the next issue coming up IMO is going to be the bearings and such. And IMO, the combined cap-girdle is a good solution for the flex down low.
Post some pics of that intake in another thread, is that a boat engine? Whats with the water system
Sorry I did not get more pix but that is their air/water intake and Intercooler combo that they use for a lot their boat engines.
sounds like the typical banks shit of your parts are junk, but buy my stuff
they only make stuff for stock trucks or off the wall exotic parts anyways
Not the reply I was looking for but it will definitely be up for sale on a post one day so don't worry.
What's special about the banks balancer? The ati is what SoCal diesel has recommended for ever. But they sell that too so it's just like banks lol. I like hearing these decisions
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