My post on the CC site about the "360" build article

[farna@xxxxxxx]

I expect a few AMCers will be a bit ticked at me for this, but this is what I had to say about the Car Craft article:

The article was informative, if you want to build a high $$$ AMC engine. Otherwise it was a bit disappointing. You REALLY need a book on AMC engines! The best one out there is done by a small shop, and is called "B.J. Builds an AMC". Okay, title is a little hokey, but contents is not! See the website (http://www.hobbyobsession.com/bjsbook.html). No relation, I just have a copy, along with AMCs own performance book (Performance American Style, copyright 1972).

Welding up rods is a bit beyond the average "car crafter" if you ask me. Lots of machine shop time in the build! The stock AMC crank is good for 7,500 rpm according to Performance American Style -- 390 and 401 forged steel cranks for over 7,500. AMC recommends the forged cranks for anything over 550 hp, indicating the cast nodular iron is good for up to that amount. Stock rods are only recommended up to 6,000 rpm (used as is). Forged 390/401 rods are listed as 8,000 rpm capable after shot peening, Magnafluxed (to check for flaws), and polished. The stock cast 360 rods should be capable of more than 6K with the same treatment. Because of age it might be a good idea to not stress the parts quite that much, but pushing it to 6,000-6,500 should be adequate for a nice street performer. 

One more thing that wasn't clear -- AMC engine "oiling problems". Problems only occur at sustained high rpm. The oil pump then proceeds to pump all the oil to the top of the engine. This is what starves the rear rod bearings. The Milodon pickup does increase volume going to the pump, but that has NEVER been a real problem with these engines. You're talking about an all-out race engine to get into the rpm range where that is really needed! 

Many drag racers never knew there was a "problem" -- 1/4 mile sprints don't have it. The T/A racers discovered the "problem" because they couldn't drain engine oil fast enough at the high rpm they were running. One solution is to run an extra line in the valley to route oil around the lifters and provide more for the rear rod bearings. Not necessary for a 400 hp street engine, but usually done for insurance. Getting more oil up from the pan has never been as problematic as the article insinuates.

You had a nice race engine professionally built, there's no doubt about it! Hopefully you'll do another that the average guy can duplicate without all the exotic machine work. An AMc 360 built with the stock crank and rods would easily put out what your street engine did without the offset grinding and required rod welding. 

I hate to "complain" because the AMC coverage is nice, but it wouldn't hurt to do a little home work. It's obvious you're not taking the time to get to know AMc engines. In a way I don't blame you -- Chevy and Ford sells most issues. 

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