Results 1 to 14 of 14
  1. #1

    AMXROCKRIG'S AMC 390 engine build

    Finally started my 390 build. Care to guess HP and TQ ratings? I know a stock 390 of this year put down 315 HP @ 4600 RPM and 425 TQ @ 3200 RPM (well according to an AMC repair manual anyway).

    Here are some pics of the build.

    Short block


    Heads and valvetrain


    Oil sprayers for cam/dist gear and timing chain


    Cool little block drains


    Remote oil filter adapter


    Top-end done


    Almost there!!!


    Quick specs:
    Motor is a 1969 AMC 390
    Bored .040
    Comp cams 282 bumpstick
    Edelbrock hardened pushrods
    Aluminum 1.6 ratio full roller rockers
    Keith Black aluminum pistons
    Edelbrock Performer aluminum heads and ARP head bolts
    Edelbrock Airgap intake
    Bulltear nickleplated timing cover, crank pulley, oil adapter, oil pump gears, valve covers, t-state housing, oil fill tube and cap
    ATI race dampner
    Flowcooler aluminum high flow waterpump
    Milodon 8qt oil pan
    Doug Thorley Tri-Y hedders
    MSD 6T Off Road ignition and Ford Style HEI cap and TFI coil
    Stock Motorcraft distributor with lighter advance springs installed
    Asperation is a Holley Commander 950 FI system.
    My name is Daniel. I pretty much do what I want.

  2. #2
    bowtied1's Avatar
    Join Date
    Oct 2002
    Location
    Grand Junction
    Member #
    1324
    Nice job!
    Blackish 91 YJ coiled blah blah blah.

  3. #3
    Dallas Lemon's Avatar
    Join Date
    Nov 2003
    Location
    Englewood, Colorado
    Member #
    3179
    Images
    10
    Awesome! That 390 has got to be diffcult to find. I know 401s are getting more and more rare, but there are probably more here in Colorado from the older Cherokees than anywhere else in the country. But 390's are few and far between. With that cam, that old AMC ought to put out some serious HP numbers. Keep us posted if you have it dyno'd. Good job!
    The Lemonator
    Jeepnut Extrordinaire

  4. #4

    Join Date
    Jan 2002
    Location
    Parker, CO
    Member #
    389
    Danny, I would dump that airgap and get the torker. That manifold is going to kill that motor. I ran one on my 401 and it was awesome. I even ran a performer for a while just to see if I really lost any bottom end running the torker, and nope..sure didn't. The high end gains are worth it since you won't lose anything down low.

    what's the comp ratio? and are you running the 390 crank or a 401 crank?

    I am going to hazard a guess of about 475hp/500ish ft/lbs at the crank and a max rpm near 7000rpm assuming the valve springs are match the cam.

    you gonna break some parts with that!
    1994 Toyota FZJ80 - elocked, 3in OME lift, 315/75-16 KM2s, Warn 8274.

  5. #5
    Trail Boss Eric's Avatar
    Join Date
    Aug 2001
    Location
    Gilpin County
    Member #
    1
    Images
    9
    Gorgeous. I'm not familiar with that approach on the oil sprayers, got any more info? Also why do you want the drain for the block?

  6. #6
    Quote Originally Posted by cmd11 View Post
    Danny, I would dump that airgap and get the torker. That manifold is going to kill that motor. I ran one on my 401 and it was awesome. I even ran a performer for a while just to see if I really lost any bottom end running the torker, and nope..sure didn't. The high end gains are worth it since you won't lose anything down low.

    what's the comp ratio? and are you running the 390 crank or a 401 crank?

    I am going to hazard a guess of about 475hp/500ish ft/lbs at the crank and a max rpm near 7000rpm assuming the valve springs are match the cam.

    you gonna break some parts with that!
    I was running the Torker before. It did scream then with the stock heads and such. But the Airgap had a RPM range between the Torker and the Performer, So I thought I would give it a try. It has the plenum like a Performer but the rise like a Torker. I ditched the T-18 and went auto, so that was some of my justification too for this manifold.

    The machine shop stated around 10.2:1 or so if I remember correctly. Honestly, I am not sure how to figure that out. I am sure I can get the specs on the pistons. I know they were ordered and matched to run with the cam compression ratio wise.

    I still running the 390 crank. The sucker is just as massive. The main bearing caps on the 390 (well the '69 anyway) are a little thicker than a 401 as well. (I had problems with a new stock oil pan fitting over the front main cap previously). The springs in the head are a double spring, so that should keep the valve float at bay should I push it.

    Quote Originally Posted by Eric View Post
    Gorgeous. I'm not familiar with that approach on the oil sprayers, got any more info? Also why do you want the drain for the block?
    Thank you
    They are actually 1/8" NPT to compression fittings. We chamfered every oil port/drain back in the motor, but I just want to be sure that rotating mass in the front of the motor gets all the oil it can. Before this build I had cam/distributor gear issues. It turned out to be a bad main bearing causing the cam to walk, which no amount of oil would cure, but it's there for that "just in case" factor and was very easy to install. I run a tee at the oil feed for the oil pressure sensor port.

    The block drains are there so if I need to tear the motor down for any reason or even to change a water pump and not make a huge mess. Even if I never use them, I'll be glad they are there when the time comes. They point straight down instead of trying to pull a pipe plug and having coolant shoot 45 degrees out of the side of the block all over the place.

  7. #7

    Join Date
    Jan 2002
    Location
    Parker, CO
    Member #
    389
    looks good! You'll have to take me for a ride once it's running

    what auto tranny are you running? I am curious because the only autos that would work behind a 390 without modification would be the borg warner slushbox. Did you go with a TF or TH400 and modify the crank to work with the converter?

    btw, those block drains are suspiciously a kevin fox touch..... did he 'work his magic'?

  8. #8
    You pretty much have all the parts I wish I had purchased for my 401. I see you spent some time and cash at bulltear.

    That purple is "pretty"...... .
    You going to dyno it at the crank?

    Also wtf is that gear on the front of the water pump? That looks like the stock gear for the oil pump.

    More info on the bulltear remote oil setup with oil pump changes pls.

    EDIT: On picture #2. it looks as though the engine had the oil mod that you run a line from the the top front back to lifters at the rear. But you seem to have capped it. Why? Or am I just smokin crack? Im sure Corey will pipe in on that.
    Last edited by Janky; November 19th, 2009 at 09:29 AM.
    Can I recommend you use a search engine here without getting in trouble?
    Search for Rock Zombie Outlaws. Come visit us!
    Thanks! :)

  9. #9
    phattdraggon's Avatar
    Join Date
    Apr 2005
    Location
    Durango/Charmington, NM
    Member #
    6246
    Dare I say .

  10. #10
    love the build and i bet it will scream. i have the same timing cover and adapter on my 360 is my cj5! keep up with more pics and dyno #'s


    i am looking for a 69 390 crank if anyone knows of one.
    It's on like Donkey Kong!

  11. #11
    Quote Originally Posted by cmd11 View Post
    what auto tranny are you running? Did you go with a TF or TH400 and modify the crank to work with the converter?

    btw, those block drains are suspiciously a kevin fox touch..... did he 'work his magic'?
    You are on top of your AMC game still Corey..
    Yep, TF727 lockup version. And yep, I had the crank machined to accept the nose of the converter.

    Actually Kevin got his motor together before me and I suggested he put his in at the time. Figured it was a good idea.

    Quote Originally Posted by Janky View Post
    I see you spent some time and cash at bulltear.

    That purple is "pretty"...... .

    You going to dyno it at the crank?

    Also wtf is that gear on the front of the water pump? That looks like the stock gear for the oil pump.

    More info on the bulltear remote oil setup with oil pump changes pls.

    EDIT: On picture #2. it looks as though the engine had the oil mod that you run a line from the the top front back to lifters at the rear. But you seem to have capped it. Why? Or am I just smokin crack? Im sure Corey will pipe in on that.
    Bulltear has some good stuff for AMC's and purple is right?

    Probably not going to dyno at the crank. I would want to do it with my FI system and really don't want to yank all of the harness and such out of the Jeep. Rather do a chassis dyno and see what it pulls.

    That is the old stock OP gear. The bolt was too long and I was letting the sealant on the gasket seal up under pressure, so I needed to keep it tight.

    The oil pump adapter comes with a steel shim plate for the gears to ride on then the aluminum adapter sandwiches that. I do need to look up which port the relief spring goes into. I think the port on the "out" side. Then I just ordered a remote mount oil filter that will hold a large Ford style filter.

    That plug you see in the pic is in the stock location. It just looks in the picture like it is on the face. I was going to do the oil line mod at first, but decided that it was not needed with the capacity of the new oil pan. I think if the motor was used in a race car that the revvs were always above 5000RPM it probably would be a good idea.

  12. #12

    Join Date
    Jan 2002
    Location
    Parker, CO
    Member #
    389
    I forgot... I think Pat B still has my old 401 block and '73 heads. not sure what he plans to do with those parts, but as far as I know, they are just sitting in a corner collection cobwebs.

    your 390 will be more than capable of spinning up to 7k, as long as you have a good fuel system to support it. It's gonna make some power that's for certain. Nice job! Now you are going make me have to go out and turn my 351w into a torque monster 393w. Funny how to make the 351w hit that CID, I have to get a 3.85in stroke crank, whereas the 390 uses a 3.585 (I think that's right) stroke crank, but the bore is 4.165 for the 390, and the 393w has a 4.030 bore. To make a 393w, I need a $300 crank, stock 302 low compression pistons, and balance it. Tempting....

  13. #13

    Join Date
    Jan 2002
    Location
    Parker, CO
    Member #
    389
    Quote Originally Posted by Janky View Post
    You pretty much have all the parts I wish I had purchased for my 401. I see you spent some time and cash at bulltear.

    That purple is "pretty"...... .
    You going to dyno it at the crank?

    Also wtf is that gear on the front of the water pump? That looks like the stock gear for the oil pump.

    More info on the bulltear remote oil setup with oil pump changes pls.

    EDIT: On picture #2. it looks as though the engine had the oil mod that you run a line from the the top front back to lifters at the rear. But you seem to have capped it. Why? Or am I just smokin crack? Im sure Corey will pipe in on that.
    that milodon pan is the one you need to eliminate your oil pressure issues... it will hold about 8 qts. I tried running a stock pan when I first did my 401 and it would lose pressure on a steep driveway. Changed the pan (this was back when it was almost impossible to get a milodon pan for an amc) added the milodon extended pickup, and no more issues. I could stand the jeep on the back bumper and it would still have normal pressure.

    stop hating your 401..... there's a ton of people who would love to have one.

  14. #14

Similar Threads

  1. Magnum CJ Build: The never-ending build CONTINUED...
    By Steven_Mc in forum General 4x4 Discussion
    Replies: 203
    Last Post: November 24th, 2014, 01:38 PM
  2. Build your own Vettes engine...
    By lilgreenjeepyj in forum Checkered Flag
    Replies: 3
    Last Post: July 13th, 2010, 09:28 PM
  3. JeepDude's CJ-7 build (AMXROCKRIG's son)
    By ZJROCKRIG in forum General 4x4 Discussion
    Replies: 23
    Last Post: March 29th, 2010, 10:46 PM
  4. What engine to build
    By 4-rocks in forum General 4x4 Discussion
    Replies: 8
    Last Post: November 23rd, 2005, 04:49 PM
  5. New Engine Build Up, little help please
    By fsjeeper in forum General 4x4 Discussion
    Replies: 8
    Last Post: April 13th, 2002, 08:48 AM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •