5.7L/L31 into an 86 Regal with 307 olds

Discussion in 'V-8 Buick Powered Regals' started by 86Regal_Pearl, Mar 10, 2010.

  1. 86Regal_Pearl

    86Regal_Pearl G ride G-Body

    I have a 1986 Regal Limited with an Olds 307 in it. The 307 never was enough power for me and in 2006 I broke it, bought a 97 Sierra with a 5.7L Vortec and parked my regal.
    Last July I wrecked the truck, totalled it. I kept the truck and took the 5.7L Vortec, engine code L31, out along with the trans(4L60E), computer, engine wiring harness, driveshaft, radiator, and other misc. stuff.

    I wanna know how hard it's gonna be to get the L31 in my Regal Limited and still have A/C, Cruise control, and keep my fuel injection and computer. I know everybody seems to feel like it's easier to do the swap by deleting the fuel injection and computer and just bolting a carb on top, but that's not what I want. I don't want this engine without the F.I., to me, that's part of the appeal of these engines.

    I specifically want to know about the wiring. I have the complete engine wiring harness, all the way up to the bulkhead, from the truck. My question is how hard is it to wire into my current setup?
    I have added a digital tach, digital speedo, and digital temp gauge all on the A-pillar that I want to wire up. Will I be able to use these and will they be accurate? If so, what's the best way to approach it?

    The more I think about the swap, the more I realize that this engine is really a self-contained system and I shouldn't have any big problems. Although, I'm still apprehensive about the fuel plumbing and the dilemma of the fuel pump & location.


    Any advice/suggestions appreciated!
     
  2. Rusty

    Rusty Dragbikes Rock !

    I have pondered the same type procedure, except I have an 89' full size van with a 350 TBI / 700r4, that is such a great running engine.

    I would suggest removal of all the old computer harness out of the car, much easier once you have removed the dash, which isn't that hard to take out. You are going to have to plan/map out exactly how you want to run the new harness and where to place the computer if it doesn't fit under the right kick panel where the original was. This might take splicing to extend the harness in certain places.
    (if you do this project make sure you document it with pictures for us, lol)

    The bolt up of the engine & trans should be pretty straight forward as there are G-Body frame pads available from many places or from a 78' - 86 Malibu or Monte, El camino. You may need a custom driveshaft, a good driveshaft place should be able to make you a driveshaft if you just take them the slip yoke from the truck and they'll probably use the rear joint from the Regal's shaft, you'll probably have to do the measuring & tell them the length.

    It's in no way a small project, and the planning of the whole harness is going to be the hardest thing I would think to lay out. Speed sensor plug routed down to where the plug on the trans will be once installed, all of it!

    Not to mention the gauges harness will all have to be spliced for the idiot lights to all work, but once you pull the gauge cluster out, with a 12Vdc supply, you can easily figure out which wire at the gauge cluster's plug will go to what idiot lights on your Regal's dash. The newer Truck will have more then the older Regal, you could use the Yellow (Security) idiot port for your Check Engine wire maybe, but these are all things you're going to have to think about, or somehow custom fit the trucks gauge cluster into the car, but I would think that would mean hacking up your dash, and probably not come out so good. The good thing is, like my 86' Regal's idiot lights are on the sides from the main sweep speedo, so the speedo could be removed and put dual tach speedo in maybe, or get one from an SS Monte.

    Just don't forget to install an in-line electric fuel pump with pressure ranges suitable for the fuel injection system.

    Before even starting this project, I would order from a Chevy dealership the factory schematic diagrams of your truck, they are not cheap, expect well over $100, but they are vital when dealing with large full wiring harness', we like to hope they are color coded end to end, but too many times I've seen a color change occurring somewhere in the harness. This is why most people won't take on the huge job of keeping the original fuel injection and wiring harness, and transferring it into a different car, but it does make it nice to keep the easy starting and better fuel economy of fuel injection.

    Good Luck.
     
  3. 86Regal_Pearl

    86Regal_Pearl G ride G-Body

    I have yet to even start on this swap, but I have plans of doing so very soon.

    I haven't taken any of the harness or computer out of the Regal. I plan on using the computer and harness from the L31 and figuring out a way to mount it under the hood. As far as the gauges, I don't plan on doing anything to the dash for right now, I have already purchased an A-pillar 3 gauge pod similar to those in the Grand Nationals, and the gauges to go in it. And I'm thinking about going with a Dakota Digital dash once I get this swap completed and the car running (and enough money to afford one).

    My biggest concern right now is the fitment of the engine & trans. Will I need engine mount adapters? If so, what kind and where do I get them? Same with the trans cross-member, will I need mounting adapter? What kind and where do I get it?

    I've searched and read all over about this but it seems as if most people are doing the LS swap or a 5.3L swap into a g-body. Or if they did use the L31, they didn't swap it into a g-body. I want to keep my A/C and not have to notch the frame. Basically, making a clean install so that it looks factory.

    Again, I want to keep my intake and fuel injection on the L31 stock. I don't want to change intakes or make it a carb motor.

    With the wiring, I have entire wiring harness from the L31 all the way to the bulkhead, I didn't cut anything. What's the best way to go about installing this? Should I cut the Regal's harness on the engine side of the bulkhead and splice the L31 harness into it? If I do it this way won't I have extra wires from the L31 harness that have nothing to splice into?

    If I remove the Regal's old bulkhead and install the L31's bulkhead in it's place, getting a mate to it from the salvage yard to go on the dash side of the firewall and cutting it a few inches up leaving enough wire to splice in everything I'll need from my dash (A/C, Cruise, wipers, gauges, horn) won't I just have to splice up under the dash?

    As for the driveshaft, I still have the aluminum one that I had made for my truck. (had to have it towed once and the tow truck driver lifted it up without the rear wheels on the flatbed :Dou:, he put an elbow in the driveshaft and they had to replace it. I came out with a custom aluminum, balanced driveshaft. :grin: ) I'm thinking that I can get a shop to maybe shorten it to fit my Regal and mod it to fit the rear end.
     
  4. gusszgs

    gusszgs Well-Known Member

    Wow, lots a work.......I'd consider selling the 5.7, and convert to an LC2 and have a sleeper LTD. JMO
     
  5. stew'86MCSS396

    stew'86MCSS396 Well-Known Member

    The L31 short block is essentially same as the original SBC. Unfortunately those Olds mounts aren't the same. Engine mounts from any G-body that came with a SBC will work. The crossmember needs to be modified or purchase one that will work with the 4L60E.

    As for the harness, you can unpin the wires from the truck connector and reinsert them where you need it on the Regal connector. Most people will cull out the unnecessary wires i.e. headlights, blinker, wipers etc. and make it into a stand alone EFI harness. Under the A/C box, is a round hole on the G-body. It's up to you how to make that square fit there. Under the dash, there's a 15 pin connector that some wires will need to be added and some repinned/relocated.

    Plumbing...I've brow beat this one for years and I still don't know how I want to bridge the gap. There are barbs and clamps, AN fittings and OE style fittings to name a few. All I know is, you're going to need a fuel pump that delivers the demands of the engine and you're going to need a pressure and return line to the tank. Here's couple of links that will give you an idea of what you may be up against.
    http://www.montecarloss.com/ls1montecarloss/July.html
    http://www.bowtiepower.com/TPIconversion.html
     
  6. gs_jimmy

    gs_jimmy Well-Known Member

    Hey, This is an easy swap. Get a set of lower engine stands (frame mounts) from a Monte Carlo (LS or SS) or ElCamino in the junkyard. Should be around $20 bucks. Then buy a set of brand new engine side mounts (Rockauto.com) for an '86 MC SS. This is important, they are not oil soaked and breakage prone like used stuff.

    Drop the engine into the car at this point. Everything will fit the body (I have done SBC, BBC, BBB with TH350 and TH400 trans, no prob). You are going to need to get a driveshaft made or cut. The TH700 / 4L60e uses a 27 spline output shaft that you should already have with the car. You may need to redrill the crossmember mounting bolt holes.

    Now that the driveline is in comes the fun part. Since this is a '97 SBC2 motor, LT1 series, check over on the LS1Tech forum for exact wiring info. But, everything should be useable (kinda ugly lookin).

    Fuel system - you are going to need a new gas tank, sender/pump and lines. Get these for a 4.3 Monte Carlo (TBI Equiped). This car ('85-88) had an in tank pump and was sumped for the extra height of the pump. It is a direct bolt in part with no mods needed. Same with the fuel lines.

    Also, go over to the truck forum and see if anyone has a wiring diagram for your '97 truck. You may end up using the truck wiring harness (underdash) to get this going. Also keep the door harnesses if you have power windows/locks.

    I belive both vehicles use the shorty a/c pump, but your car was running R12 and the truck was running R134 refidgerent. Also the evap/suitcase and related are G-body specific.

    The only real problem you may run into is overall engine height. Sometimes the intake cover can be removed and the studs taken off (ground down). The accessory bracket may be a problem too. I know the LS series has these problems. Again, LS1Tech has the exact answers on this.

    Make sure to post some pics!
     
  7. GSXMEN

    GSXMEN Got Jesus?

    The Vortec is not an LT1 engine. Oddly enough though....some of the L31 Vortec engines did use the same '411 computer as the LSx engines did. Most of those that I've seen were in the late 90's/early 2000's Express style vans.

    For those in the know....that would give you the option of installing both a crank sensor in the front and a cam sensor (dist.) for an older SBC. Plus all the tuning options that the LS1 guys have. There is a company called www.eficonnection.com that is offering kits to do just that.
     
  8. 86Regal_Pearl

    86Regal_Pearl G ride G-Body

    Again, revisited!

    I'm gonna get this car built this year even if it means I have to compromise on the end result.

    I know some of you all may think this is a stupid build idea, but I know what I already have in the L31(head job done 3 months before I wrecked truck), and trans (rebuilt 4 months before wreck), and I wanna use what I already have....to get to a desired result. A daily driver that gets as close to 20mpg as possible, has the reliability & convenience of fuel injection, and is a pleasure to drive.

    Its posts like this that give me hope!
    First, the trans is a 4x4 with the manual transfer case on the tailshaft...will it work with this swap if I just change the tailshaft?

    Also, the tank I have is a replacement tank I bought from gastanks.com, will the 4.3L MC sending unit fit? If not, what about using a GN sending unit/pump along with the MC 4.3L pressure & return lines?

    I have the engine harness and ecu from the truck (from under hood), why would I need the under dash harness from the truck? Also, both car and truck have power windows/locks, why would I need door harnesses?
    Where can I find more info on this?
     
  9. sean Buick 76

    sean Buick 76 Buick Nut

    Yes you can use the 4x4 trans if you change the tailshaft except the issue is that you have to take the trans appart and basically rebuilt it in order to do that. I would just find a 2wd 4L60E, or better yet leave the 2004R in place. This way you do not need to cut the drive shaft, wire up the trans, move the crossmember, etc. I really see no advantages to the 4L60E trans and it is a lot of work. The 4L60E trans must be run off the factory computer OR an aftermarket controller however they are about $800.

    I would use a Q jet carb, you should have no issues getting 20 MPG with that carb. I have no issue getting 22 MPG with my Q jet. A simple intake swap, engine mounts and your swap is done.

    If you do go with the fuel injection then I suggest buying a "painless" wiring harness for a 97 truck and then re-wiring the WHOLE vehicle. This is the best way to go since you can actually trouble shoot things later iff you have an issue. Trying to patch together two factory harnesses is a HUGE ordeal.

    Another idea is it go with something like an aftermarket fuel injection system. This would save you TONS of time!
     
  10. 69GS400s

    69GS400s ...my own amusement ride!

    Scott - your wealth of knowledge has never ceased to amaze me over the years

    ... V8Buick is a much better place with your postings :beer
     
  11. 86Regal_Pearl

    86Regal_Pearl G ride G-Body

    Update

    So my 74 y/o neighbor is instructing/helping me on the engine swap part since I've never done one.

    We took the radiotor out, disconnected all wires/ plumbing, and unbolted engine and trans from mounts. All that is left to do before we pull it out is disconnect 2 lines on the passenger side of the trans that are a bitch to get to, and disconnect drive shaft.

    My mechanic that installed the 307 & rebuilt the TH350 that's in it now(getting pulled out) isn't working on any really physical stuff anymore because of health problems and I understand that. He said he'd swap the shaft in the 4L60E for $250, so I took the transfer case off and dropped it off Sunday. He said he'd have it ready Saturday.

    The only things that I'm concerned with are the wiring to the dash, I'm pretty sure I wanna install a Dakota digital dash for this and I guess I might as well do it all at the same time. I'm thinking about buying the digital dash online and taking it and the whole car to the customization shop that installed my sunroof and have them do it and install my viper alarm. This would be after I set the engine and trans in and have everything mounted correctly.

    ---------- Post added at 11:37 AM ---------- Previous post was at 11:26 AM ----------

    Will the in-tank sender/pump provide sufficient pressure to the L31?
    Will the in-tank sender/pump from the 4.3L Monte Carlo fit into the gas tank I already have? (it was new a few years ago, bought it from www.gastanks.com and don't really wanna waste money buying another if I don't have to)
    Will the fuel lines from the 4.3L Monte Carlo connect to the L31? If so, how?
     
  12. 71gs3504sp

    71gs3504sp Well-Known Member

    Just a thought,
    Since the 307 olds is exactly the same as an olds 350.
    Why not sell what you have and get/bolt in an olds 350.
    No change to trans or drive shaft.

    If you car was a buick 3.8 then you can just bolt in a SBB.
     
  13. 86Regal_Pearl

    86Regal_Pearl G ride G-Body

    ...
     
  14. v8regalowner

    v8regalowner Silver level contributor

    I was looking up gas tanks today, the regal 307, monte with the 4.3 and the regal turbo cars (also fuel injected) all show differnt part numbers for them. it looks like they all have the same external measurements so the difference must be in the hole for the sender. now they all list the same number for the lock ring that holds the sender in so that shows hope for the swap. i could see the fuel injected cars having some sort of baffle in there to keep the fuel around the fuel pump which could be the differance. i could not find any listing of what the psi was that the monte carlo fuel pump put out in comparason to the one from the sierra. i would think worst case scenerio you would buy an after marked high performance one for the monte set up and you would be fine. the fuel lines arnt going to be the same but i know dorman makes alot of repair ends for fuel injection line so you may just have to get something that can splice into your existing line that runs through the car. seeing that your running the computer from the truck your going to have to make sure all of the sensors from the truck like the mass air flow, map and coolant temp are all hooked up or the computer will tell the motor to run too rich or too lean. these are all the things that are going to be the hardest i bet. the physical mounting of everything shouldnt be too bad.
     
  15. steve covington

    steve covington Well-Known Member

    Exterior dimensions are ALMOST the same. The M/C 4.1 tank and TURBO REGAL 3.8 tank are the same tank wise with a plastic baffle reservoir to trap fuel for the in-tank fuel pump, but use different fuel pumps and senders. The M/C used TBI; a relatively low pressure fuel injection. Turbo Regals used significantly higher pressure system on SFI cars...
    The regular M/C 5.0 and "Regular Regal", along with other "G' body cars, use a different style tank; and only have a sender, no reserve baffle inside; the fuel pump is a traditional lever operated external can type pump. I know that the fuel injected cars have longer bolts at the front of the staps with spacers; don't recall if "Regular Regals" have the spacer (and longer bolts) as well.
    The Fuel injected cars also use a high pressure fuel filter mounted in the fuel line under the car back by the lower trailing arm mount on the drivers side. Fuel injected cars use THREE fuel lines: Supply, Return, and Vent. Carbureted cars only have TWO fuel lines: Supply and Vent. And you will undoubtedly soon find out that GM installed the fuel lines on the frame BEFORE the body was dropped on the frame:ball:... YES there is a fuel line clamp with the bolt BEHIND it where the rear axle is located on the frame. Three Guesses as to how you have to get that bolt out to change the fuel line... ANNNK. time's up. RAISE THE BODY!!! Now remember, the front fenders are attached to the body at three points each, and to the radiator core support as well, and that fragile front header panel. HAVE FUN.
     
  16. 86Regal_Pearl

    86Regal_Pearl G ride G-Body

    Thanks a bunch y'all!


    Steve, there has to be a better or alternative to raising the body?

    Why would I change that fuel line? Wouldn't I just be running a return line(a braided steel one from summit racing) to go along with the already existing Supply & Vent lines?

    I was thinking that, in worst case scenario, I could just add an inline fuel pump somewhere along the fuel line on the frame :Do No:
     
  17. steve covington

    steve covington Well-Known Member

    You will need a high pressure capable filter in-line between the in-tank pump to keep particulate contamination from reaching the injectors...Unless you like buying injectors constantly...and CRAPPY mileage because of injectors sticking open from the crap not filtered out. You MIGHT be able to rig a filter where the flex lines go from the sender to the stock hard lines; You have to replace those hoses anyhow...like you said with adapters and high pressure hose...
    The body is so close to the frame there that you can't get any kind of socket on the head, much less back it out. Crawl under, and feel above the driveshaft where the body meets the frame; you'll see (actually FEEL) what I am talking about. I wen't through this when I was putting the 86 GN engine in the 84 t-type. (84/85 have fuel filter in engine compartment between A/C compressor and engine block on a bracket).
     
  18. 86Regal_Pearl

    86Regal_Pearl G ride G-Body

    This is before we got the engine and trans out, we were disconnecting everything
    2012-06-17_13-59-57_598.jpg 2012-06-17_14-00-11_254.jpg 2012-06-17_14-01-59_271.jpg 2012-06-17_14-02-11_24.jpg

    Alas! The engine & trans out
    2012-06-18_21-29-06_140.jpg 2012-06-18_21-14-11_42.jpg 2012-06-18_21-14-22_100.jpg 2012-06-18_21-14-34_645.jpg 2012-06-18_21-28-32_840.jpg 2012-06-18_21-28-53_171.jpg 2012-06-18_21-14-03_457.jpg

    I picked the trans up Sunday from getting a new shaft put in, it's sitting off to the side. I need a Neutral safety switch for it, the one I got is busted and cracked.
    And I need to get the L31 out the garage and put the starter on it and bolt the trans to it.

    First engine swap! SO EXCITING!
     
  19. 86Regal_Pearl

    86Regal_Pearl G ride G-Body

    Now I understand what you mean about the engine stand and engine mounts.

    I had to get some engine stands (the part that bolts to the engine on the L31) from the junk yard (pull a part) and I figured since I was already there I would get the part that bolts to the crossmember/frame and I couldn't get them off. The bolts just kept turning and not backing out. I deduced that there had to be a nut on the other side....inside the crossmember. So I gave up on that and figured I could buy THAT part at the parts store because it obviously is supposed to last the life of the vehicle.

    I came home and bolted the engine stand( I actually only needed one side because it was cracked) and saw why and how the L31 is wouldn't mount to the existing mounts. I also got a new Trans dipstick while I was there... perfect fit.

    So, tomorrow, or today, whichever way you wanna see it, I'm gonna get new engine mounts (the part with the rubber that bolts to crossmember/frame) from Advance auto parts. I started putting the truck's wiring harness on, just plugging it up to accessories, so that should be done by tomorrow.

    I also wanna get, at least, the plumbing for the fuel lines tomorrow, maybe not the fuel pump, but I wanna be able to put the engine in knowing that I have the lines that fit and only have to worry about wiring and paint :D
     
  20. 86Regal_Pearl

    86Regal_Pearl G ride G-Body

    Ok, so I went and bought the motor mounts for the 97 GMC Sierra that the 5.7 L came out of.
    Removed the original Buick motor mounts that were on the frame; had to jack the car up to get an extension and angle joint up through the opening in the frame where the lower control arm is... a little frustrating, but I got it :)
    Then I kinda played around putting the mounts on different holes by just inserting the bolts as placeholders, just to eyeball it and see if the angle would look right to me.
    Decided to leave 'em in the 2nd & 4th holes (from the front of the car) on the top, and 1st hole on the bottom of the mount.

    Now the hard part, putting the engine back in BY MYSELF. I lifted it up as high as it would go in front of the car, I had a come-along attached to the tail shaft of the trans to level it out even. I pushed the whole hoist, with engine & trans hanging in the air, up to the car. I had to slack off on the come-along to get the tail shaft pointed down once I had it over the engine compartment..... aww, I'll spare y'all the details. I got it in, but the mounts don't match up.
    The engine is still on the hoist, right over the mounts.

    Check out the pics:
     

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