best way to build a 360/401

[78J-10]

Well the time has come for my engine to be built and I'm kinda lost on the best way to build these bad boys. I have a 78 360 that I'm going to fully re do but don't know what to do. I would really like a stroker of some sort maybe a 406? But I have not been able to find much info.all the machine work for the block and heads is free to me so I'm not limited to much by funds. it goes to the shop in 3 weeks. So let's hear what all you smarter then me forks have to say :)

I am running kieth black pistons for sure

[Elliott]

Have it balanced internally and gasket match the heads with a light polish and you will be plenty happy with what it builds/flows. BullTear has some nice mods for the oiling system and a ton of sweet AMC parts. Your choice of cam is probably one of the most important decisions about what the motor will do for you. Some guys have posted up their recent experience with Lunati's Voodoo cam and Lunati also makes a nice high rpm lifter. That's the stuff going in my 455.

I'm figuring you were planning on an aluminum manifold...
Now, you might want to review these threads:

http://www.ifsja.org/forums/vb/showthread.php?t=106695

http://www.ifsja.org/forums/vb/showthread.php?t=121315

[J20 project]

1: Realize that your knowledge base is probably less than AMC's..
2: Double roller timing set.
3: Top end oiling mod to equalize the pressure.
4: Choose camshaft based off of your future usage..Call summit or someone that you would trust in this. I chose a 1200-3500ish cam made by Melling. My engine builder had a fair amount of exp on this so I trusted him..So far so good. Getting a cam that works good for 4500 rpm on one of these beasts doesn't make a lot of sense.
5: Have it balanced as suggested..
6: When in doubt,,refer to #1.
J20 project

[billyrb]

#1: ask Ristow :)
#2: repeat #1

[fasteddy]

Ditto the 1200-3500 rpm cam
There is no substitute for cubic inches
Hypereutectic pistons are plenty for what you are building - forged is overkill
Hayes makes really nice chrome rings
I'd have the crank nitrided
I'd have the piston skirts antifriction coated
I'd do some pocket and flash cleanup in the ports, and gasket port match
Do every lube mod available
cc the combustion chambers and balance the motor
convert to FI on a good dual plane manifold

You want to build for the maximum low rpm torque consistent with regular fuel, so 8.5:1 is probably max for compression

[Josh D]

Since you have access to free machine work I would suggest milling, drilling, tapping rocker pedestals for screw in studs and guide plates and go with some Harland Sharp roller rockers. I'd also recommend hardened exhaust valves seats for longevity.

If cost is not a factor, Edelbrock RPM aluminum heads would be nice.

As for the bottom end, a blue print rebuild with quality parts and ARP fasteners would be plenty stout.

[Skeeter74]

You can have the crank offset ground to use Chevy sized connecting rods and gain a few cubes.

[Ristow]

#1: ask Ristow :)
#2: repeat #1


...cause i always have an opinion,don't even have to ask most times....


you can use a 401 rotating assembly with custom pistons in a 360 block.

otherwise for a daily driver type truck you can get some decent power out of the 360. Automatic trans? you're shifts will be limited to the low 4K range unless the governor is modified. point being to cam it for the application.

i like to go a bit mild on my cams,i'll take a broad smooth powerband at the expense of a little mid-range punch over a more peaky cam with lousy low end torque.

I'd have the crank nitrided

not a bad idea. i wish i had on my stroker. i think in the future i may pony up for it. it's about 30-40 a journal i think? x 9 on a V8.

i like the performer grind for a cheap cam. i have the little voodoo here,unused yet. the bigger voodoos' have good reports.

open up the exhaust. dual is best. not a huge header guy,but they do make power. but even a good dual setup with stock manifolds will give some punch.

i don't subscibe to the valley line mod myself. a good oil pump prep,and/or a new cover,with good oil pressure will do.

[78J-10]

This is not going to be a daily driver at all. So i can get a little crazy with it.

MY idea the first time around was to use 401 rotating assembly with custom pistons. But i didnt know were to start looking for pistons. I want to build this right the first time. I figured you guys know ur stuff better then me.

MY motor will only be able to be in the shop for about 6 weeks friend only has so much time.

My main problem were im stuck now is. I have a 401 roatating Great Googley MoogleyGreat Googley MoogleyGreat Googley Moogley. but were would i get pistons from?? And I have 60cc heads but is there anything i could do to them to free up a little more power??

Ristow- I know you are the man to talk to on this stuff could you point me in the right direction sir??

All others- Will be balancing the rotating Great Googley MoogleyGreat Googley MoogleyGreat Googley Moogley and might have the pistons coated not sure yet. But deff going hardened seats

[Ristow]

oh,there's plenty of guys here with more knowledge then me in this department. i do have some real world input however.

wiseco makes pistons however you want them,and they're among the best.

i got the shaft on mine because i bought mine through a speed shop who didn't take the time to discuss his customers (me!) needs with wiseco prior to construction-he just had them built to his quick dimensions,so my pistons were specs incorrectly.wrong shape,wrong alloy,wrong dimensions! he then told me it was my problem and take it up with wiseco,even though wiseco built them exactly as he ordered. i have since talked to wiseco several times,and new correct pistons will be made when i'm ready.

you'll have about 800.00 into the pistons. custom tailored to your compression choice,and relief style.

mine had fantastic torque,and got over 13.5 mpg doing it. it was in my '91 GW. 9.25 compression.ran on 87 octane. the new stroker will be 9.5-10. on the compression.


get a real cam. the summit cams are cheap grinds. the 8600 just plain sucks. i had the 8601 in my stroker with rhoads v-max lifters. ran great but the oil pump couldn't keep up with the fast bleed lifters,and oil pressure suffered at low rpm. next time it'll get the little voodoo.

i've read love and hate with coated piston skirts. no real world input,i've not used coated pistons. wouldn't be against them if the opportunity arose.

get at minimum roller tip rockers,if not full roller lifters.

aluminum heads are nice,but the cast iron heads will make a lot of power too.

[78J-10]

I have been looking at KB and wiesco for pistons. I run wiesco in my 4 wheelers and have had great luck.

Ristow what set up are you running for your stroker?? 360 block w/401 bottom end??

is rhoads the only one that makes roller tip or roller rockers for AMC heads??


Not enough room in my budget for alum. heads at this time. prolly gonna try and work the stockers alittle bit to help.

Im not a huge fan of giant cams, looking for a good idle and mid range torque curve. Im going to look into the voodoo cam a little more.

[fasteddy]

Re piston skirt coating, I've done the research. Two 3.0 Mitsu v6 motors built, one with stock pistons coated, one without, normally aspirated, hayes rings, both .010 bored and Sunnen honed by the same machine shoip, same machinist. Both torn down at around 50k miles to be further modded and freshened up and dished pistons installed for turbo mod.

Uncoated pistons showed wear to 38% of service limit. Coated pistons were unworn. Uncoated bores worn .003", coated piston bores unworn.

I'm convinced that quality coating works. I've also had good luck with heat shield coatings for hi boost turbo piston crowns.

I'm partial to iron heads for big v8's that may have extensive low speed high load operations (off roading), especially with older radiators and a/t's. All aluminum heads bow some, and will bow enough to stretch head bolts and kill the head gasket seal if overheated once. They work harden over time, and are thus prone to cracking, especially between the valves. Great care must be taken in fitting valve guides because of the mismatch in coefficients of expansion (which causes the head bowing problem, too).

A roller rocker is always nice, and makes a couple of extra ponies. I'm also a fan of roller lifters for camshaft longevity and faster open/close profiles.

[Ristow]

401 crank/rods in a 360 block. the iron heads have the big AMX/SS valves 2.08/1.74

rhoads are the lifters. i have harland sharpe pedestal roller rockers,there are several other good brands.

[78J-10]

Sweet thanks Ristow.

Didi you have to mod youe heads to get the rockers or are they direct fits? i have have read that the stud needs to be changed and some clearance needs milled in the heads.

[Ristow]

the pedestal style are bolt on for the later bridged heads.

you can't pick the correct pushrod length til the components are all put together,and neither can comp cams.

[HerrKooled]

since CNC machining and labor is free, port and polish the Great Googley Moogley out of the heads.

Who makes a good hydraulic roller cam for AMC motors?

[Elliott]

I ran stellite valves in my Triumph and they carried me through 9,000+ rpm. Triple Isky springs, chrome molly pushrods...

If you wanna build a roller cam get over to the AMC forum and read up on the machine work there.;)