1. Registration trouble? Please use the "Contact Us" link at the bottom right corner of the page and your issue will be resolved.
    Dismiss Notice

71 Cj5 Chevy 4.3 Liter With Efi

Discussion in 'Builds and Fabricators Forum' started by Simplegreen21, Feb 7, 2020.

  1. Feb 7, 2020
    Simplegreen21

    Simplegreen21 New Member

    California
    Joined:
    Apr 29, 2017
    Messages:
    24
    I have a 71 CJ5, it has the shorter front end. I would like to swap in a 4.3 liter V6. I haven’t really done much with truck engines before, so this feels a bit overwhelming to me and I hoping for some guidance.

    From what I have read the common swap includes pulling the entire engine, ECU, and wiring harness from a donor vehicle and swapping it in. I don’t think I want to go quite that route though. I would like to get an engine that would normally use a carb and use something like a Holley EFI, thus eliminating the need for the factory ECU and all the wiring/programming issues that come with it.

    First, I am trying to determine what year/version engine would allow this as most already have fuel injection and I don’t think they would accept a carb/EFI. Do I need to get a crate engine if I don’t want something extremely old and high milage?

    I think one thing I would need is a distributor, I found this one: A-Team Performance 4.3L 262 V6 EFI to CARB SWAP 65K Coil Complete HEI Distributor, Spark Plug Wires, and Pigtail Harness For Chevrolet CHEVY/GM GMC 90° V-6 One Wire Installation

    I am hoping to mate this to a SM465 transmission and use my existing transfer case, a dana 18 with a single stick. I have read through the Novak guide on this and it seems like a good combo.

    I’ve included some pictures of the tub I have been working on cutting out all the rust. It probably won’t be too pretty, but I wanted to see if I could do it anyway.

    Thanks!
    [​IMG]
    [​IMG]
    [​IMG]
    [​IMG]
     
    melvinm, dane71, fhoehle and 3 others like this.
  2. Feb 7, 2020
    scott milliner

    scott milliner Master Fabricator

    Seattle Wa.
    Joined:
    Dec 17, 2002
    Messages:
    2,361
    I bought a complete running truck for my 4.3 ltr swap. If you can. Find a rare 4.3 manual truck. This way you won't have to flash the ECM/PCM/VCM or what ever they call the computer. Oh. Stay way from 95' S10 trucks. I made that mistake.
     
  3. Feb 7, 2020
    Dphillip

    Dphillip Member

    Omaha NE
    Joined:
    Nov 25, 2008
    Messages:
    322
    I believe the carbureted Chevy V-6 was late seventies to mid eighties with TBI starting around 1985 or 86. So those engines would be pretty old. Years ago we put a 4.3 with a carburetor in my friends CJ and that V6 came out of a 1980 El Camino. Late 1980’s and early 1990’s Chevy S-10 and Blazers all used 4.3 with a TBI and the junkyards are loaded with these simple but reliable engines.
    My suggestion would be to use a TBI on your 4.3 with a aftermarket wiring harness. This makes wiring up things very simple. I put a 4.3 in my CJ over 20 years ago that I pulled from a junked 1991 Chevy truck and used a Painless Performance wiring harness. You can’t go wrong with fuel injection.

    Also, your body work looks great!
     
    Alan28 and Rich M. like this.
  4. Feb 8, 2020
    Jw60

    Jw60 Sitting up n buckled down. 2024 Sponsor 2023 Sponsor 2022 Sponsor

    Sedalia MO.
    Joined:
    Apr 8, 2008
    Messages:
    4,717
    1985 a few 1986 and marine or crate are the only years for Carburetor on the 4.3 previous to that was the 200 and 229 v6 with dualjet carbs. You can put a quadrajet intake or tbi to carb adapter on but the fuel pump boss went away from the block in 86 along with several other major changes so unless you already had a 200 or 229 in the jeep there is no reason to look for an 85 block. Use 88 to 92 and get the tbi running in the jeep. stick it thru and don't look back.
     
  5. Feb 8, 2020
    47v6

    47v6 junk wrecker! 2023 Sponsor 2022 Sponsor

    USA
    Joined:
    Oct 25, 2006
    Messages:
    5,798
    Did your jeep come with the V6 dauntless?

    here is your info
    General Motors 90° V6 engine - Wikipedia
    I am going to put a 2000 4.3 in my cj2a in front of a SM420. It is rated at 190HP factory. It had the SCPI fuel deliver which breaks and the MPFI has been installed instead with the distributor upgrade.

    I bought a GMC safari van running and driving for 500 bucks, stripped the entire wiring harness out of it along with the engine and 4l60 auto transmission. If I got the rare passenger drop transfer case, I could have had an automatic w OD. I decided I like shifting gears and want the d18 with an over drive for the Rube Goldberg experience.

    I spoke to Howell products and they will reflash my computer, but he said it will run with no modifications, just not right. He sold me on a reflash and a wiring harness to save me days of work and headaches.

    Any flywheel will not work, get the correct one for a manual s10.

    From my perspective, not using the native FI is a mistake as these parts are off the shelf available anywhere. This is what I am doing.
     
    Rich M. likes this.
  6. Feb 8, 2020
    Simplegreen21

    Simplegreen21 New Member

    California
    Joined:
    Apr 29, 2017
    Messages:
    24
    Thanks for the input guys! It seems everyone agrees sticking with stock fuel injection is the way to go. Does it matter if I get the engine/harness from a van vs S10? Would there be parts that the S10 would have that the can would not? I called a few junk yards a few months back and most seemed to have newer 4.3s from Silverados and none included wiring harnesses or any accessories. I am in Central California, does anyone know of a good place around here I could check out?
     
  7. Feb 8, 2020
    47v6

    47v6 junk wrecker! 2023 Sponsor 2022 Sponsor

    USA
    Joined:
    Oct 25, 2006
    Messages:
    5,798
    I have the entire wiring harness out of the GMC Safari. Its a huge pile of wire... I spoke to the guy at Howell and he said it takes him 8-10 hours to trace every wire for the harness and discard the ones you don't need. I am buying a custom harness from him for like 500 bucks. Count the hours and multiply it by a fair rate to see whats its worth to you. Some things like welding in your motor mounts isn't easily outsourced, but plug and play is worth a lot to me.
     
    fhoehle likes this.
  8. Feb 8, 2020
    Dphillip

    Dphillip Member

    Omaha NE
    Joined:
    Nov 25, 2008
    Messages:
    322
    I don’t think there would be much difference in the wiring harness between an S-10 van or S-10 truck but it’s important to know what year your donor vehicle is. Throttle Body Injection was used on the 4.3 until about 94 or 95 I think? After that it was a Tuned Port Injection system that in my opinion is slightly more complex than the TBI.
    The TBI has a lower fuel pressure, only one Oxygen sensor and the ECU is easier to adapt to your build. No flash is needed just the proper chip to control the automatic transmission if you use one.
     
    Alan28 likes this.
  9. Feb 8, 2020
    sterlclan

    sterlclan Member 2022 Sponsor

    exploring the...
    Joined:
    Feb 21, 2009
    Messages:
    3,869
    ill echo earlier info , stay away from the 95 cpi injected 4.3
     
  10. Feb 8, 2020
    mortten

    mortten I can’t put my finger on it 2024 Sponsor 2023 Sponsor 2022 Sponsor

    Peninsula, Ohio
    Joined:
    Apr 17, 2006
    Messages:
    1,738
    The later CSFI wasn’t much better. Still had the poppets.
     
  11. Feb 9, 2020
    masscj2a

    masscj2a Member 2023 Sponsor

    Ware, Mass
    Joined:
    Dec 27, 2013
    Messages:
    743
    Back a few years ago I installed a 4.3 out of a 2000 Bravado. Sent the computer off to Hollywood Hot Rod and they sent me back the corrected ECU with the necessary deletes and up dates for standard tranny, gear ratio, tire size. Think it was a four wire connect. It also included dual O2 sensors. Bought the correct flywheel from Advanced and swapped out the spider in the FI for the updated individual injectors. Ran with the very first turn of the key. I also installed a inline Bousch fuel pump attached to the frame. Installed the rear tank from a 71. Return fuel pressure was around 2 lbs. Can't tell you how well that combo ran, it was amazing. That motor was in front of a T15 and Dana 20 case with 18 guts and Terra low.
     
    Alan28, Fireball and 47v6 like this.
  12. Feb 9, 2020
    Simplegreen21

    Simplegreen21 New Member

    California
    Joined:
    Apr 29, 2017
    Messages:
    24
    Thanks for all the help, I will keep my engine search going! While I do that I might as well make this a better build thread and cover what I have done so far.

    I bought the Jeep about 3 years ago thinking it was mechanically sound and just needed a little body work and some paint. You can see it looks pretty good in the picture below and i fired right up and seemed to run well.
    [​IMG]

    Unfortunately, that was not the case. The engine had a bad head seal and had to be machined. I thought that was good, but there was still coolant in the oil. Turns out there was a crack in one of the cylinder walls. I had the entire engine rebuilt, but a few months later there was knocking noise. Took it back and he said there was an issue with the cam shaft, which he fixed. It seemed good for a little bit, then it started to lose oil pressure when it warmed up. I replaced the oil pump, but the rear main seal went and it just pissed oil out the back. These series of events led me to where I am today, replacing the engine.

    Here is what I have done on the Jeep so far.
    First it had a keg as the gas tank, and while unique, wasn't really what I was looking for, so I got a new gas tank and moved it to under he drivers seat.
    [​IMG]

    I also built new seat brackets and put in new seats. The home made brackets that were in the Jeep were very poorly made and only attached in two places.
    [​IMG]
    [​IMG]

    I also replaced the front fenders as he had gotten the wrong size and just cut them to length and used self tapping screws to hold everything together. I replaced the wheels and tires because I would like a more classic look and this removed the need for wheel spacers.
    [​IMG]

    I removed the after market taillights and filled in the holes, I also filled in a whole that was cut in the back cargo area from when the keg was back there.
    [​IMG]

    So that more or less leads us to today where the whole Jeep is torn apart and I am starting over again. As you saw in the pictures above there was a lot or rust, which was hidden with bondo and paint. I started to see cracks and rust leaking through after a year or two, but I didnt realize how bad it was.

    This is my first project with a full sized vehicle, I have only ever done a small motorcycle before. I have learned a lot so far, especially that I should know a bit more about a vehicle before purchasing it. I will keep this thread updated as I make progress.

    Here's a picture of the 68 Honda CT90 I restored several years back.
    [​IMG]

    [​IMG]
     
    melvinm, fhoehle, Snoops and 5 others like this.
  13. Feb 9, 2020
    Fireball

    Fireball Well-Known Member 2024 Sponsor 2023 Sponsor 2022 Sponsor

    Pullman, WA
    Joined:
    Feb 9, 2018
    Messages:
    5,627
    Cool bike! Those things are a hoot.
     
  14. Mar 10, 2020
    oddfirejeeper

    oddfirejeeper Active Member

    Hamilton, MI
    Joined:
    May 5, 2004
    Messages:
    1,253
    love the ct90's...I've got a 1965 ct200 which is the same bike (still a trail 90). My grandfather bought it brand new and original title and has only seen the light of day 3 times since the middle 70's when it was put away. I fired it up for the first time since the 70's in 2003 and drove it around the yard and put it back into my barn for a restore and put in a 125cc lifan in it.
     
  15. Mar 10, 2020
    Muzikp

    Muzikp Active Member

    Sacramento Ca.
    Joined:
    Sep 27, 2016
    Messages:
    1,450
    Those wheels and tires look awesome (y)
     
  16. Mar 11, 2020
    Simplegreen21

    Simplegreen21 New Member

    California
    Joined:
    Apr 29, 2017
    Messages:
    24
    Work is slow going, but I have completed just about all of the work on the floor. I cut pretty much all of the front floor out and all of the floor supports as you can see in the earlier pictures. I have all the sheet metal replaced and I built out a floor support based on what was there before. I boxed all of it in with the goal of mitigating future rust since it seemed like a lot of rust was due to the floor supports holding water. I even welded tubing into the body mount holes. Now I just need to patch up some smaller holes in the body and build the support for the rear wheels wells (Which I also cut out due to rust).

    [​IMG]

    [​IMG]

    [​IMG]
     
    melvinm, fhoehle, ITLKSEZ and 2 others like this.
  17. Mar 13, 2020
    Norcal69

    Norcal69 Out of the box thinker 2024 Sponsor 2023 Sponsor 2022 Sponsor

    Northern California
    Joined:
    Sep 6, 2014
    Messages:
    3,549
    I wish I would have sleeved the body mount holes when I installed my floor pans. Nice work.
    Next time I tear my jeep apart... I am going to sleeve the body mounts...
     
  18. Apr 24, 2020
    Simplegreen21

    Simplegreen21 New Member

    California
    Joined:
    Apr 29, 2017
    Messages:
    24
    I got a few more things done while I continue to work on a parts list for the engine. I patched up a few more of the larger holes in the body and I built the rear wheel well bracing, including the extra sturdy brace for the spare tire mount.

    Here you can see a few of the smaller hole sections I filled in and the drive side wheel well bace.
    [​IMG]
    [​IMG]

    This is the passenger side brace with all the extra support for the spare tire. It even has a hole that bolts it to the roll cage, though that was purely by accident not by my original design.
    [​IMG]
    [​IMG]

    This does finish off the majority of the major body patching and fabricating work. but I am sure all the little spots will take some time to patch up.
     
    melvinm and Muzikp like this.
  19. Apr 27, 2020
    Lilbuff63

    Lilbuff63 Member 2022 Sponsor

    Sonoma County Ca
    Joined:
    Jan 12, 2014
    Messages:
    285
    Just spotted this thread! I’m a little late to the party but just wanted to tell you what I did. I got a crate 4.3 from the early 90’s, sourced the accessory brackets from pick n pull and eBay, headers from Novak(good source of technical info also). Installed an edelbrock TBI intake and stand alone TBI system from Performance Fuel Injection that comes complete with all sensors, wiring harness, ECM, distributor, very well put together and easy to install. Fired up the first time and runs great! About 18 mpg and plenty of power! Did the sm420 adapted to the Dana 18 and added an overdrive, going 65 at about 2,200 rpm with 4:56 gears and 33” tires. Here’s my build thread Buffs 58 cj5 build: Buffs 58 cj5 build
     
    fhoehle, givemethewillys and Muzikp like this.
  20. Jul 13, 2020
    Simplegreen21

    Simplegreen21 New Member

    California
    Joined:
    Apr 29, 2017
    Messages:
    24
    Well, its been a bit since my last updates, but progress has been made.

    First I added the toolbox area under the passenger seat. I'm not sure yet if I am going to add a lid to it.
    [​IMG]
    [​IMG]

    I also got my engine! 4.3 liter V6. It's a remanufactured engine from ATK. I installed the intake manifold, harmonica balancer, water pump, pulleys, flywheel, and clutch.
    [​IMG]
    [​IMG]
    [​IMG]

    I also got my transmission in. This is a SM465 rebuild from Novak.
    [​IMG]
    [​IMG]

    I slapped everything together, but probably not for the last time. I am trying to get the positioning correct so I can weld in the engine mounts from Novak. This is my first attempt at getting things somewhat in there. Unfortunately the hoist cant reach for enough back to fit the engine from the front.
    [​IMG]
    [​IMG]
    [​IMG]

    Hopefully my next post will have the engine mounts installed! It looks like the original transmission crossmember isn't going to work as it would hold the transmission way too high. Anyone have any advice on building one? What gauge should I use?

    Thanks!
     
    melvinm, dozerjim, Muzikp and 2 others like this.
New Posts