401 INFO NEEDED

[GADJIT98]

Just need a little info to get me started......

Where can I buy / borrow a AMC V8 technical manual with all the specs, etc to rebuild my newly found 401?

Has anyone seen the AMC 401 build & Dyno show on Horsepower TV?
They claim to have built a 401 with relatively minor mods and got it up around 500hp.

What I need is info / links to point me in the right direction to build this 401 the RIGHT way and have good power that will last for many years on the street.

Thank you in advance for the info, and also thanks for past help

Dave :t:

[Lifted79CJ7]

Hey Dave!! Sorry I missed your call - been one hell of a week, and this upcoming one isn't looking any better! So how's the engine look? Still ingood shape? Did you guys get it yanked ok?? Send us some pics! :mrgreen: Anywho, drop me an email and we can find a some time to hook up sometime!!
lifted79cj7@aol.com
Jack

[jeepsr4ever]

Dave

Their are alot of threads on a 401 buildup and alot on a 360-390 build up right here in the performance parts topic area and the engines area. Do a search and post up any questions you may have.



Nice find....what is the head casting #?

[GADJIT98]

OK, here is what I got........ :mrgreen:

The block casting number is : 3198951

The Valve Cover has a tag with: 610Z23

There is alot of dirt & grease on the motor so I cant find the head casting number. Where should I look on the head? The exhaust manifolds are still on it .....can you see the casting number without removing them? It will be a few days til I can get it cleaned & on a stand to really look it over.

Jack, as soon as I get this thing cleaned & on a stand, could we hook up & take an educated look at it? say maybe in a couple of weeks?

Dave

[Lifted79CJ7]

Well, according to the valve cover tag (http://www.amcrc.com/tech/engine.html), your engine was built on October 23rd, 1973. To find the casting number on the had, you have to take the valve cover off - it's cast into the head near the valves....

http://www.bulltear.com/forum/viewtopic.php?t=541

Actually a couple weeks sounds good. This upcoming weekend I will be in Vegas, and next weekend a friend is coming to visit. Heck, you still got a killer deal on it, no matter how you look at it. Did it come with all of the accessories?

[GADJIT98]

Jack,

Yup, has the PS & ALT still with belts attached, no carb though, & has an e-brock SP2 intake that will be promptly gotten rid of in favor of an R4B or Performer, hell, it even has the clutch& PP to use for cores!

I am planning on a TOTAL build with this one including balancing & blueprinting, whatever that means. I have heard "blueprinting" all my life, but have no idea what it actually involves.

Gonna get a new cam, oiling assembly, & all the goodies to hopefully make this a bada$$ street motor that will be durable & efficient enough to be a daily driver and still lift the front tires :lo1l:

I'll start posting pics as soon as I get It cleaned

Thanks
Dave

[GADJIT98]

As I was reading thru all the threads, I read that the 401 has an 8.35:1 comp ratio in stock form. If this is the case with this motor, how high can I get the CR and still run 87 octane gas & get the HP that I want (350-450)?

Also, I want it to have a distinct performance idle & sound, but I dont want to lose vacuum for the PB. What on a cam affects vacuum? Lift or Duration, or both?

I have no idea how high my max RPM's will be, but I pretty much drive the hell out of this thing so I want to get as much as possible. Will the R4B be a good choice, or should I stick to a Performer.

These, and many more stupid questions COMING SOON

:razz:
dave

[Blown7]

Hey Dave, Think mission profile what are you going to do with this engine. DD, drag, sand drag, rockclimb streetrace? Everythings a tradeoff. First IMHO you can't get 350 hp and above on 87 octane pump gas reliably w/o detonation you'll have to go 92+. Then ask yourself where you want to make that horsepower in the rpm curve 2000 RPM? 3000 RPM? 4000 RPM? at idle? at redline? Then your torque curve, when do you want that? Idle? mid range? Second have plenty of money or a good machine shop at your disposal for "Blueprinting" Blueprinting ( I hate that word) along with Balancing (I hate that word too) involves checking the all the dimensions and grinding, machining, boring, honing, all the parts of the engine to a table of limits and tolerances that conform to factory drawings and specifications to bring all parts (block, heads, crank, to a acceptable level. The closer all the parts are to basic and all held to a high tolerance the better. On the bright side I find AMC parts to be usually pretty close and have some lead way to work with as opposed to SBC/BBC why anyone would want to work with those is beyond me (but thats another story) So for your first question if you want 350 to 400 hp on 87 get a blower :? I'm partial. Second question for vacuum a engine or specifically all the 8 cylinders only creates vacuum on the intake stroke the longer the duration of the intake valve opening will make the most vacuum, but then the trade off on overlap and scavinging come into play. Forget vacuum too and get a hydroboost for the brakes. :lo1l: First look at alot of cam specs talk to alot of knowledgeable people in the industry spend lots of time picking a cam ( the cam is always the first choice on any high performance engine build and the most critical) I cannot emphasize enough that the cam is the thing you build a engine around, is the most difficult thing to learn and understand, hell I bought three to run on the dyno and picked the best of the lot. Your redline RPM will be dictated by the quality of the cam, valve springs, spring pressure, connecting rods, rod bolts, pistons. If you can find any of the old books by Smokie Yanick on how to build a SBC from the 60's and 70's there is a wealth of info in there that apply to any engine. As for manifold IMHO go with direct port fuel injection forget carbs those things are so old school, so old I think they taught that subject with the flat earth theory. So take your time and ask questions about the cam first line item by line item. Jeff

[GADJIT98]

Jeff,

I had heard that about building around a cam. What is the profile on the stock 258 inline six motor. I like the way it performs, just not enough of a kick in the pants for me.

Blower...........hhhmmmmmmmm

I have a friend that has a 671 blower for around $600 I think. After the initial purchase of the blower, what else do you have to do? I assume a blower intake?????? and how much of a cost are the pulleys? can you run an alternator and PS pump off the blower setup or do you need a different setup? I have never built a blower motor, so I am ignorant on the do's & dont's. Also, can you fit a 401 with a blower & single carb, & air filter under the hood of a CJ?

The blower idea sounds like a cool way to go, but it may be over my head. What kind of MPG would you get on the street with a blower?
Like I said, I would love a blower, if I can get it done within budget-$2500 to 3k installed from this point.

Dave

[Blown7]

Now your cookin! I don't know what a 258 has for a cam. I only used them for boat anchors. Now yes a blower setup could be done for 3 K but you have to watch what you buy. Now the great thing about supercharging a 401 is if it runs, and runs well don't take it apart, just add manifold, blower, drive and preferably a Unilite distrubutor for a basement setup. Believe it or not the 401 has everything you need in there to run up to 6 PSI boost, 8 PSI if you watch it carefully. You can run accessorys by a "rubber' pulley system ( a system that just rubs the side of a pulley)or in my case somewhere on this forum is a mock up pic of my engine with the original accessory drive intact and the blower drive foward of that. The manifold can be made out of a aluminum Elderbrock with the blower mount welded after the center is of the manifold is removed by milling. Go to BDS website and read all of the info there and also Dyers for a background on blower setup. Watch a used blower for backfire, most times it'll be junk. But you don't know until you use a feeler gage to check the blower clearances, CC clearance even, .005 at the bottom, sides equal, no binding of the rotors .007-.008 clearance on the front rotor to case measurement, .015-.017 back rotor to case clearance. A 8 inch drive snout on a AMC is minimum I have a 10 inch. Dyers IMHO has a drive system for AMC that for the price and quality can't be beat. I bought a new Black wrinkle 6-71 blower from Bill at Dyers last week for 850.00 you can deal with the guy. A blower if conventional mounted with stick up thru a CJ hood but in my case only the bugcatcher protrudes, if you want to get real stealth you can side mount a blower so nothing is shown but hell with the looks I get I wouldn't want to hide what I have. Even to stop for gas is a group event with me mostly having to push my way thru the crowd (warning this can get annoying if your in a hurry) So if you use list prices, blower manifold 800. blower 850. drive 1000., carbs new can run 700 a peice you need at least two 650's set up for blowers, magneto 600 unlite 200 airfilter ??? whatever you want. now if you shop around not on Ebay people there think they have gold parts and the auction frenzy is nuts hit auto flea markets, make you own manifold, find a gem of a deal on a blower (don't skimp there) find used blower carbs I think you can do it for around three grand. Plus alot of time on your part. The bottom line is a blower will make the engine think it's twice as big 800 cubes, plenty of torque from idle thru redline, conservative HP around maybe 350 @ 2500 rpm and and no need to screw with cams, lifters, heads, valves, pistons. ( I did because I wanted a CJ 7 rototiller with 18 inch paddle tires for sand drags). Fuel economy will be a little less if you drive easy, but who does with all that shiny stuff on top, every damn 5 liter Mustang wants to be humilated I guess) and the same for any normal aspirated driver and whatever is aside of me at a light. My best show was last week against a alchohol BBC in 1/8 th mile. I was told by a fellow who builds high end engines that if my engine was in a AMX or Javilin it would be a soild 9 second engine. But thats about it for a 401 with stock crank, and rods. So on to my next build a eight second Eagle wagon. Jeff

[GADJIT98]

Jack & Jeff,

Short of doing a Blower....it still just sounds way cool :lo1l: ......I was thinking about something like this:

http://cgi.ebay.com/AMC-AMX-JAVELIN-JEEP-401-MOTOR-ENGINE-HIGH-PERFORMANCE_W0QQitemZ8006319658QQcategoryZ9886QQrd Z1QQcmdZViewItem

I know very little about all the specs, etc. , but do you think this is a good setup, & is it possible to build a similar motor for 2500 - 3k?

Dave

[Blown7]

I don't like the fact this engine was overbored, but you'd have to ask someone like Fuzz 401 who has built a normally aspirated big hp engine what his engine cost. Jeff

[Lifted79CJ7]

PArts wise, yeah, it can be done, the machine work will be the killer. The HP is all in the details - both prep work, balancing, smoothing, reassembly, etc. Do you have an aircompressor and tools?

[GADJIT98]

Jack,

I have a compressor & a pretty good shop....or should I say I have a 12x24 foot tool box :lo1l: I dont have any enclosed area to work on my rig, but I do have a (^&*-load of tools, etc to work on it with! I think most of my machining will to the pro's, and maybe the final assembly. My guy says he will warranty it if he assembles it, but not if I do it.

Jeff & Jack,

What dont you like about an overbore? I always assumed a little was OK, but too much, say 60 over, was asking for trouble. I am hoping this motor I got is still a virgin but if I need a bore, I will keep it as low as possible.

I crunched some numbers and the blower idea looks like between 5k & 6k with the rebuild and balance / blueprint so it is not an option now. I am however keeping my eyes peeled for a good blower setup for cheap. If I can find a reasonable way to do a blower, it will be stuffed in there!

What kind of cam specs do I need to look at for a good street cam? I want it to run like hell streetlight to streetlight and have good power on the highway. What kind of lift on each lobe, and what duration? I want a bit of a performance idle, but I dont have to have that bumpity bump like an old built out the wazoo SBC, just maybe a hint of it to let people know I have something interesting under my hood.

Thank you guys for taking the time and effort to help me, I hope I can repay the favor someday.

Dave :razz:

[GADJIT98]

I got the valve cover off today and here are the numbers...............

3220502-2 on one end of the head

10-22 in the middle of the head

NH one the other end

E somewhere near the middle

Does this mean anything?

Thanks
Dave

[jeepsr4ever]

502's were common dogleg heads used from 74-up so you have a common, rare 401. 8.5-1 compression if its stock...dont worry htough you can build it to the hilt

[Lifted79CJ7]

I'm not too strong on cam specs, but the reason overboring on a 401 isn't the best idea is due to thin cylinder walls/overheating issues. Try to keep it stock if you can - AMC blocks have nickle content so they are pretty strong and durable..... MC care to chime in here?

[GADJIT98]

WHAT ABOUT A TUNNEL RAM?

I have seen them and the look great, wonder what the pro's & con's are with one.....either single or dual quads.

Hell, I even thought of having a "six pack" or even those old school , eight carb setups with one carb per cylinder. If I use the 6 pack, I already have one weber 32/36 to start with :-|

Just a little daydreaming. Most likely I'll do an R4B intake with a Holley 650 double pumper.....any advice?

Thanks, Dave

[Blown7]

Stick with something simple to start, it seems like your kinda new to this, eight carbs, a six pack or any more than one carb to tune and get all the linkage to work correctly for now will just get you discouraged and wonder why everything doesn't work right out of the box, nothing ever does! Stick with a good 650 and a good manifold to start. You'll have enough trouble with that setup to get it on the running good. Jeff

[fuzz401]

you want light to light or more go with the air gap intake

[GADJIT98]

I was thinking about either a Performer, or an R4B, which do you suggest?

Jeff, Good call, yes I am new to building engines, pulled many, but never built one. I think your advice is the way I am going.....single 4bbl on a Performer or R4B. If I run across a setup later that is interesting, I'll adress it then.

I hope to be able to get into this motor in a week or so and actually have some REAL information such as actual bore, rod / crank specs, etc

Thanks, Dave

[rollen dean montoya]

jeff has the right idea. stick with the "K.I.S.S." method(keep it simple
you now the last one). thats how my dad taught me to build. do one
first and keep it as close to stock as possible. make sure you torque
everything to specs. plastic gage the crank and rods your manual will
have the specs. check all bores. personal experience for me is if the
bores differ more than .005" you might have to do a minimum bore job
to even out the cylinders.hot tank the block ,heads, intake,valve covers ,
and oil pan.
good luck, later,rollen

[tarior]

but the reason overboring on a 401 isn't the best idea is due to thin cylinder walls/overheating issues.

Sleeve it!! 8)