Can you run a forged steel crank that has been reground and not Nitrided after grinding? I have a 283 (now 301) with a crank that came out of a Formula 5000 and I don't know if it was done as it was a while ago. Could I run it with good additives or pull the crank and get it done? Its in my 26 RPU and wont be driven hard. It has around 10:1 comp with power packs and raised top pistons if that matters. Cheers JW
A safe bet is the majority of typical performance builds do not include a nitrated crank. The original forged cranks were mostly likely induction hardened that varied in depth but might have penetrated .030. Nitride ,AKA Tufftride or ferritic nitrocarburizing, penetrates about .010 or less. The cost is by the pound. It costs 100 bucks to nitride my 12 pound motorcycle cranks...Car crank is probably 200 bucks My race bike ate some junk that scored the rod bearings badly...No damage to the Nitrided crank journals.
Nitriding is EXTRA protection. The 426 hemi was one that had it and they have been ground and survived very well. I myself had one for several years that was .030" under with no issues even drag racing it eventually. It would be nice if it had been retreated but I would run it as is for now. If it is ***embled properly it is unlikely to be a problem and if eventually you wish to have it treated then fine. I would be very surprised if you have any problem ever in your application. To put it in perspective ,modern Chev cast cranks are almost as soft as cheese so to speak and still seem to function very well. BTW I use nitriding for flat tappet camshafts. Comp Cams will do it for you when you order. Last one I had done was around $100 extra which not to have trouble with a high spring pressure flat tappet cams with todays "iffy" lubes for flat tappet was to me a bargin. I would expect the camshaft to be more of an issue prone part then your crank in your application. don
Dolmetsch, pardon my ignorance, but I have little knowledge of nitriding. Is what you're saying that with a proper nitriding procedure, camshafts can survive without concern for the lack of zinc in modern detergent oils? Posted using the Full Custom H.A.M.B. App!
I would not run a flat tappet cam without zinc even if it was nitrated. Break in is the key. Use a break in specific oil (Edelbrock, Joe Gibbs Racing, etc.) or at lest a non-detergent oil. The detergent in oil and zinc are both polar molecules that are attracted to the pores in the camshaft. So give zinc a chance and don't use detergent oil during break in. About 3 twenty minute heat cycles at 1500 rpm will insure proper protection of the cam. Jim Ford
I wouldn.t dare it to fail but it seems to eliminate the possibility. The new oils are a big help but they were not always there when this first became a problem and are not perfect. So let me just say it this way and you make your own appraisal. I have never had a nitrided cam fail. don
Thank guys, that has put my mind at rest. This is what I was thinking and mostly hoping. Many thanks. JW
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