Unbelievable crap gets posted on the net. A smart person would realize the above post is crap knee deep. Its impossible for a properly assembled NON-nitrided crank to walk that fast. A poor man builds a motor that walks before he can even get it to the dyno and blame the shit on mitsubishi. People like deadsexy read it and make the wrong assumtiom because they have no mechanical experience or not enough to make any kind of intelligent decision. Him like many others just shovels the crap to others by being post happy. CAREFUL what you READ. most of it is CRAP from people who shouldn't be working on their own cars.

there is nothing in magnus text that is worth reading. he openly admits that after cutting blocks in half, he can see no difference from 6 to 7 bolts that would cause crankwalk. he can only offer the squirter theory as a possible cause. and he does that after checking a crapload of squirters to see if any are stuck open. yet he cant find even ONE.

 

That just reinforces that there is a difference between the two cranks (beyond the number of holes), and this is not in question. It doesn't provide any evidence that there is a causal relationship, though, between this difference and crankwalk rates. The exact same correlation can be make with holes as well (although, it seems absurd to consider this relationship to be a causal one). You might be surprised, though, at how often people infer causation from correlation while ignorning or simply not identifying confounding variables.

It's really not that difficult to set up a fairly well controlled experement in this case, as already stated, if we assume that the driver has no effect on crankwalk rates (and ~ 600 (400 nitrided, 200 not) test subjects is overkill, I must admit, but I prefer several tests with large sample sizes for obvious reasons).

 

Cory your right. Nitrating the 2g crank is a theory... based on the fact that there's no actual fact that it will help reduce crankwalk from happening on an early stage. Right now all it is... is a hypothesis. There's no conclusion. Just theory yet hardly any testing.

So with that said this theory is only at its very first stages... just baby steps... not really any actual experiments taking place. So people what your believing is a theory... one man's idea, one man's train of thought in what he believes will work. Well until its proven its just another opinion not a fact.

Believe what you want but most believe in proven things not one person's word. Thats like saying at the end of the rainbow there will be a pot of gold. Which we all know thats not the case.

 

This constant arguing over what causes crankwalk is dumb.
I dont have any idea what actualy causes it.
But I do believe that the nitrating of the 2g cranks helps fend it off just like the factory nitrated 6bolt crank tends to fend off crankwalk.
I am not sure how anyone could say that the nitrating of the crank plays no part in crankwalk. There may very well be more to it but it definitely plays a part.
Deductive reasoning tells you it has to.

I am still partial to 6bolt motors though.
When I get my EVO one day that may change though.

 

What I know is if you remove the nitriding from camshafts they will wear out in months. This will happen in every motor. Not even dsm specific. Its just a known fact. Cams must be nitrided. This is knowledge not theory.

When you remove the nitide coating from a crank. The crank wears out quicker. The rods bearing spin very easy. And the thrust surface wears down much faster. This is also fact not theory. again not dsm specific but very common knowledge. Also common knowledge 7 bolts spin bearings very easy comparred to 6 bolts . They also walk easier.

If you cant make the jump here and understand that if you go the opposite direction and nitride a surface that previously was not you gain durabilty. In the case of cams you gain literally 300 times the lifespan. How hard is it to believe that nitriding the crank will add durabilty? All I see is you are stupid if you dont get this. The definition of stupid is one without intelligence. It is knowlege not a theory.

You are right though. testing this knowledge in a dsm 7 bolt is not going to happen. I have stated many times it is impossible to test in practical terms to show the ignorant. So the theory is just a theory and always will be. Thats fine with me. Your loss. Takes knowledge to go fast.Too bad your not gaining any here.

 

What is the exact spread? Is it 150 high, 140 low? That's still within the 14 psi service limit spread, but that's pretty low overall, maybe at or near the service limit for 2g. I know it's about 35 psi drop allowed on 6 bolts, to around 120 psi, and 2gs start around 175-180, so it sounds like it really might be time for a rebuild. Although you might as well have the head redone while the engine is out, so the guide/seal problem will be eliminated at the same time.

 

That's a whole lot of equivocation, inflammatory nonsense, and a clear misunderstanding of my contention.

I don't care what causes crankwalk in 7-bolt 2g engines. And, I'm fine with the contention that nitriding a crank increases its durability (a tested claim). But, I am bothered by people making claims about causal relationships without testing when the questions are empirical and can be tested. It's fine that you believe you're onto something, but to offer your idea as law is careless and misguided (a claim, I believe, that you've made of several others in this thread and the other 6-bolt v. 7-bolt thread who have done essentially the same thing you are doing here).

The jump you refer to is a giant leap. The proper jump would be to the hypothesis that (A) not nitriding the cranks in 7-bolt 2g engines causes (B) crankwalk, at which point you would test that claim. When the preponderance of evidence suggests that (A) causes (B), then you present it as such. You've jumped from "this is an interesting observation" to "this must be the cause," and that's reaching (without testing).

This sort of leap occurs all the time in other contexts. I'm not sure why you cannot recognize the error in this one.

 

I have admitted in all my discussions of crankwalk that it would take too much to actually prove the theory. It would take 100 cars with 50.000 miles each for starters.(not gonna happen) Yet the results would still be inconclusive because we dont even know the ratios of current 6 and 7 bolt walks.

My conclusions could just as easily be proven by running 100 6 bolts without nitrided cranks for 50,000 miles ( not gonna happen either) For me that would also prove the theory for you it would not. Thats the difference between me and you. I know what the expected results would be, You say we cant predict the results and it needs to be tested.

I guess we will agree to disagree on the subject.

 

This is the first time I've heard it. If that's the case, my bad (but you certainly didn't qualify your claims in that way here).

The percentage of 6-bolts that walk compared to the percentage of 7-bolt 2g engines that walk (I assume this is what you're referring to) would not really matter, though. The test would incorporate two groups of 7-bolt 2g engines (two like groups), controlling for extraneous variables either directly or through a large, random sample size (I think the latter would be much more difficult), and making one group the nitrided crank group and the other non-nitrided. If 50,000 is the benchmark, so be it. After 50,000 miles, bring them in and check for crankwalk. If there is a significantly greater number of crankwalk victims in the non-nitraded group, and assuming we have adequately controlled for extraneous variables, then this would suggest that you're correct.

This (placed in the aforementioned 7-bolt experiment) would actually only tell us about 6-bolt cranks.
I certainly know what results you expect. But, your expectations may not be met. That's why you test. The test allows you to predict results well.


I disagree - j/k.

 

I so far have seen one of Jerry nitrated cranks survive a severe accident where he installed a nitrated 7bolt crank into a car and the owner caved in the oil pan by mistake and starved the engine for oil severely to where the bearings almost welded to the crank it was major damage but the crank did survive and it spun all the bearings and I don't doubt that if that crank was not nitrated it would of not survived where a original crank would of been gone because I did suffer that problem once and my 7bolt crank didnt survive at all and I shut down immediately but no luck it didnt survive. I encourage him to continue his research on this I would love to see it work it would make our lives so much easier with 2g's lol