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I have a JDM EVO 3 4g63t in my 1999 Eclipse GSX, Now it has a bad rod bearing and has scared the crankshaft. The only good crankshaft I have is out of the 1999 4g63t. I have searched all over and some places list the cranks from 1993 to 1996 diffirent from 1997 to 1999, Other places list them the same from 1992 to 1999 :dunno:. Can anyone help me with this?? or even have a crankshaft that will work at a good price??
 

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JDM EVO 3 4g63t, i have seen a lot that are 6 bolts? In fact i think all of them are 6 bolts. Someone can correct me if I'm wrong. Now depending on the crank it might be great to get turned. Post some pictures of it.
 

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Elite DSMtalker
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You cant turn the 4g63 crankshaft.
 

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Because it removes the nitride hardening.
 

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Well you don't have to worry about that on the 7 bolts because they don't have any nitride hardening lol. Only on the 6 bolts. So yes you can use your old crank or get yours turned for like around 100 bucks. Inspect the other one check for wear, spec it out, get it polished if nothing less.
 

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The 1993 service manual states and I quote: "Caution a special surface treatment has been applied to the crankshaft. Do not machine it to undersize." The 1993 IS a seven bolt last time I checked.
 

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It could say anything it wants and maybe that was a brief thing that was done in 93 but trust me all 7 bolts past that point did not have any nitride hardening. That was a huge issue with wear and thrusts among others. Talk to any huge dsm shop out there and they will tell you the same. Nitriding isn't a "coating", but a molecular surface and subsurface treatment of the actual metal. But for real the factory stopped doing it on just about all 7 bolt applications that I've ever worked on and seen. Which i can say is in a excess of 250. Tell you what take a file to a trashed 6 bolt crank then to a 7 bolt crank. I can grantee you this it will eat right threw the 7 bolt and not the 6 bolt, and that's because of this.
 

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Elite DSMtalker
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It could say anything it wants and maybe that was a brief thing that was done in 93 but trust me all 7 bolts past that point did not have any nitride hardening. That was a huge issue with wear and thrusts among others. Talk to any huge dsm shop out there and they will tell you the same.
Wtf kind of statement is that? Then we should just disregaurd the specs in the service manual then too?
 

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No I'm not saying that I'm just simply saying that they might of done that on a few select ones in the start of production of the 7 bolt but they did not continue it at all into the 2G's and i even doubt a year or two into the the 7 bolts at all. Its a well known fact around here they didn't I've sent a lot of customers cranks out to get nitrided. All I'm saying is entertain what I'm saying and see for yourself. I'm not trying to be rude or anything. Just simply trying to spread wisdom of years of experience.
 

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It's true that the 7 bolt cranks aren't nitrided.

But even if they were coated like the 6 bolt cranks, the coating is .030" deep. Turning the crank .010 is very common and in most cases doesn't hurt anything. To be safe, make sure the machine shop magnafluxes the crank and cleans the oil pathways. The 2g FSM says you can use oversized bearings if the crank needs to be turned.

My mains and rod bearings are .010" over and the crank is fine so far, I also know of more than one motor using a cut crank that makes over 700whp.
 

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It's true that the 7 bolt cranks aren't nitrided.

But even if they were coated like the 6 bolt cranks, the coating is .030" deep. Turning the crank .010 is very common and in most cases doesn't hurt anything. To be safe, make sure the machine shop magnafluxes the crank and cleans the oil pathways. The 2g FSM says you can use oversized bearings if the crank needs to be turned.

My mains and rod bearings are .010" over and the crank is fine so far, I also know of more than one motor using a cut crank that makes over 700whp.
The factory service manual states otherwise!!! I would never use a cut crank ever.
 

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And to just sum it all up please read this article, its a local Tampa Bay Dsm club site. Jerry who is one of the smartest people around here explains everything I'm saying in great detail. Which includes 7 bolt cranks get crankwalk very easily when it is rarely seen in a 6 bolt engine. ALL 7 bolt cranks including the ones in the new EVOs are not nitrided from the factory. The 93/94 7 bolts are very rare car so you don't hear much about them. Those are the ones that are mentioned in your service manual. It should also be noted that 7 bolt cranks have no detonation resistance like 6 bolt cranks. This is another reference to it most people are wanting the stroker crank these days. Low mile 7 bolt stroker cranks are much easier to find than 6 bolt counterparts. New is always best and they are not that expensive. If the crank is not hurt too bad it can be turned down and then nitrided. new ones need to be nitrided as well, and finally The only significant difference between a 6 bolt block and 7 bolt block is the nitrided crank.

You will not find a lot of internet information on it. Its more of a hands on deal. Here is a link to the thread.

http://tampabay.dsm.org/phpBB/viewt...&start=0&sid=b7923df5cd4287d41d95cd83279f0fdf
 

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I have a JDM EVO 3 4g63t in my 1999 Eclipse GSX, Now it has a bad rod bearing and has scared the crankshaft. The only good crankshaft I have is out of the 1999 4g63t. I have searched all over and some places list the cranks from 1993 to 1996 diffirent from 1997 to 1999, Other places list them the same from 1992 to 1999 :dunno:. Can anyone help me with this?? or even have a crankshaft that will work at a good price??

But back to this, if your 99 crank is good use it. Spec it out and have a machine shop at least polish it and check for any imperfections. You can get it nitrated however that costs about $300-350. Most shops have a batch done at the same time thus a lot cheaper. But in some cases its just smart to spend the extra money and just get a eagle or manley crank. The great thing about a stock size crank is you can play with your oil clearances, depending on your ability's. The final answer to your help issue is use the 99 crank that will be at the best price lol.
 

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Always keep in mind that not all 7bolt cranks are nitrided and not all 7 bolt cranks are non nitrided, and that you are ALWAYS better off with the nitrided versions.
 

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I'd say at this point 93 and 94 blocks are very few and far in between. If you find a block that you in fact think is a virgin 93 or 94 that has not been ripped apart, run a car fax on the vin otherwise you will never have any idea. You can find the vin number on the transmission side of the block next to the deck of the block.
 

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Nitriding can be very easily confirmed on any crankshaft for that matter.
 
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