The 401 can use a quite healthy cam w/o any additional valve notching done to those TRW pistons, they are not even flattops, they have quite the dish and you will have to have some work done to get up to the 9.5~1 they claim. Which means you will be detonation prone more so than at 11~1. You will have a hard time getting the needed .040"~.045" piston head to cylinder head clearance with those pistons. I have a set here now that someone milled out like HDMD says to do. Had close to an eighth inch of clearance and would ping even with race gas. That's also called self-destruction. Those pistons have almost the same head design as stock, they may be exactly the same, and I recall they wee approved for NHRA stock class, which means they DO have stock dish. I think they use the big rings like the stockers as well (I may be wrong about that, do check). For performance, you should use 1/16" compression rings. If you have a couple of hundred extra bucks, go for TotalSeal gapless rings. They are worth an extra chunk of power (20 or more HP) after break-in, and should have 0% leakdown after break-in.
I would strongly advise AGAINST buying that kit, or any kit. Buy each piece to fit what you want to do with the engine.
The Ross 13.25~1 flattops are a much better way to go. They do have valve notches though they are not specific to AMC but generic. What year are your heads? If they are the later model ones and if someone is doing head work to open the combustion chamber, you could easily end up with 11~1 or less. Which would be OK with pump gas if your carburetion, timing, & cooling system are all in good repair and tuned correctly. It makes an enormous difference in power (around 50 HP in an engine built to run strong).
You have to figure out how you will run it, what RPM range it will be used for. The design is easily capable of over 7000 RPM, over 500 HP, & over 500 ft/lbs. of torque, with the correct mods. Getting one to burst to 6500 & have 500 HP/500 ft/lbs. is a fairly easy and will still have more than enough torque down low, somewhere around 400 ft/lbs. at 2500 RPM.
You DO need a head plate, for sure. Have them box up your stuff and find a speed shop that knows AMC before your hemmorhoids reach the floor!!! There is a place in Jersey, I think, called Pro Motion that does good AMC work.
If you opt for the 500 HP burst to 6500 redline route, and if your valves need to be replaced, you can use stainless undercut swirl-polished 2.08/1.74 valves (Milodon, Ferrea, etc.) to easily gain another 30 HP for around $150 plus labor.
You should also have your head's spring seats turned to use cup seats, a 1.5"~1.65" diameter x 1.95" tall spring. Better to do that correct the first time than have to pull the heads later to do it. If you opt for a smaller cam, there are many spring packages that will fit those dimensions. Then later, if you decide to go for more cam, all you have to do is use air pressure to hold th valves closed while you install a more aggressive spring package. Very easy, if the machine work is done the first time through.
The airgap has a little more down low but the Torker has more up high, your call. An 850 double-pumper is definately not too much for a strong 401, if you are geared correctly & have a stick, or performance converter.
The 292H is a good cam (the 280H loses 25 HP & gains 9 ft.lbs. tq) but is a chevy grind. I have heard that Crane uses AMC specific grinds but I have my doubts. Doug Herbert custom grinds cams to the customer's wishes. He can make one for you after he asks you some questions.
http://www.dougherbert.com/
The anti-camwalk kits are made by Nick Alfano, may as well go to the source:
http://www.matadorcoupe.com/Alfano.htm
An MSD style ignition is worth the expense when you can afford it.
Be sure to see the Bulltear threads concerning oiling mods & distributor gear wear. Put your engine together yourself.
If the engine is put together and maintained correctly, it could be good for 20 years or more w/o teardown. Switch to synthetic oil after 1500 miles (according to TotalSeal), keep it clean, and keep the intake air filtered.
The mods I have discussed here do nothing to add to engine wear and serve to make the engine run more efficiently. A more efficient engine makes more power. The gas mileage should suffer little, depending on what your right foot does.
Get the "Performance American Style" book!!!!! It has all kinds of good tech.
If you notice from my posts, I try to push ppl towards higher performance rather than being conservative. This is because the "dogleg" heads flow so VERY good that putting a Performer intake or 650 carb or small-tube headers on a 360 390 or 401 serves to choke it down when the heads want to flow way more. I believe that the heads are the heart of the engine and everything else should compliment those fine ports.
Off-brand guys will want to argue that you shouldn't do that, ask them how many AMCs they have built and if they even have one, then decide who you will believe. Maybe they have a vested interest in having the AMC guys make less HP, and for good reason!!!
I'm sure there's much more to say, but my fingees are getting shorter & shorter!!!
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on the blocks being machined with the smallest cam bearing in the front. The front bearing is different from the rest (wider), so it couldn't be put in the rear journal. That would mean a different sized than stock front bearing, and also a cam which was machined with it's journals backwards to fit. Not to mention the block being installed backwards in the milling machine at the factory (I doubt the fixtures would have allowed that). It just doesnt make sense. If you can show me one of these blocks, I'd love to see it, along with proof that it's factory. I've had literally dozens of AMC v-8s apart. I have seen that the factory cam bearings are prone to flaking, but never any mis-machining. More than likely, if something is that wrong, it's been done outside the AMC factory.
