Register now to get rid of these ads!

4.3 V6 Questions

Discussion in 'The Hokey Ass Message Board' started by blown240, Jul 14, 2010.

  1. blown240
    Joined: Aug 2, 2005
    Posts: 1,654

    from So-cal

    Sorry if this is a beat to death subject, or if its not traditional enough, but I did a search and didn't find as much info as I thought.

    I am thinking about dropping a 4.3 V6 and auto trans into my 51 Chevy. I think that, bang for the buck, its seems to be the best option for a cruiser. Decent gas milage, power and dependability & I can get a wrecked S10 for under $1k.

    But I haven't heard if there are really any big downsides to this motor, and to be honest I don't know much about them.

    My other option is a 4 liter Lexus V8, but a Lexus in a Chevy? Well, you know...
  2. That engine is pretty good. I'm curious what years are you looking at (what kind of injection). The Lexus is great if you're going for weird and hard to find
  3. the chevy 4.3 is a good motor , i have one in my `95 S-10 with 262,000 miles and still runs great

    however...if you are going to do the work to transplant a motor/tranny it should be a V-8. good running SBCs are everywhere for cheap $$$$
  4. Erkenbrand
    Joined: Aug 6, 2009
    Posts: 102


    I've had several S10s with that motor / trans combo. Some of the later ones built ~2000 / '01 and in that range have problems with their injection spider. Once the miles start to get near and cross the 100k mark, that spider fails, and at $300 it isn't a cheap one to replace.

    The earlier motors are pretty good. If you find a non-Vortec motor you'll have one really reliable motor. The Vortec ones look good, but have some issues. The non-Vortecs had plenty of power, decent gas mileage, and would be an easy drop in for pretty much anything.

  5. wvenfield
    Joined: Nov 23, 2006
    Posts: 5,322


    The 4.3 is an excellent motor. You can find a good running V8 as cheap though. Fuel mileage is decent but not really a big advantage over a small 8. I'd average 18-19 or so with my S-10.
  6. Bigchuck
    Joined: Oct 23, 2007
    Posts: 1,145

    from Austin, TX

    Lexus V8 as in LS400? Run away fast. Those are a major pain to work on. I know, I work on that kind of stuff for a living. For example: the starter in under the intake mainfold in the valley between the heads. Losts of platic covers and formed vacuum likes that get brittle with age. Not to mention the ugly factor. If you really want to put a Toyota combo in it, go with a 3.4/ automaic out of a '96 up truck.
  7. Alienbaby17
    Joined: Sep 13, 2005
    Posts: 918


    The 4.3 is a good motor. I remember someone telling me that the design was basically a 350 block with two cylinders cut off. In my experience they are extremely durable and reliable engines.

    The question will be in how you choose to deliver fuel to the engine. If you run a carburetor on it you should have very few problems. However like was said above the fuel injection systems on these cars are really pretty terrible. The throttle body, low pressure fuel injection set-ups used on some of the earlier models are the exception to the problematic systems. I would actually say they should be as reliable as one of the carbureted models.

    Any of the high-pressure central fuel injection models with the "crab" style fuel injector in the intake plenum had tons of problems with the fuel systems. I just worked on one yesterday with starting issues. Fuel pressure regulators and crab assemblies were VERY common failures along with fuel pumps.

    I work on a lot of modern cars. GM made some of the worst systems along the way (lates 80's through 90's) and the set-ups on these motors is right up there with the most prone to failures.

  8. aaggie
    Joined: Nov 21, 2009
    Posts: 2,531


    I built a 4.3 and 350 TH for my '37 Terraplane and used an Edelbrock intake with 500CFM carb. The combo works great and has plenty of power for cruising. I used a later '96 engine from an S-10.

    If you set up the mounts and install the engine as far back against the firewall as you can, there will be room to put in a V8 later. All of the motor mounts and stuff is the same.

    The engines are strong and I had a GMC Sonoma that went way over 300,000 miles without problems. One water pump, tires and brakes.
  9. arkiehotrods
    Joined: Mar 9, 2006
    Posts: 6,477


    I'm gonna be contrary and say I don't like the 4.3 at all. I've owned several, including one in a 2006 Silverado that I bought new (and still have). If you're looking for an engine that has no low end, no mid-range, and no high-end power, with only average gas mileage, I'd say go for it.

    Most magazine reviews for the 4.3 give it thumbs down. I have a friend with an Avalanche with a V-8 and he gets better mileage than my 4.3, not to mention the difference in power.

    People say the 4.3 runs forever, etc, but that's because the engines don't have enough power to hurt themselves.

    I know a lot of people will disagree with me, and that's fine, but I am speaking from my own personal experience with these engines. I'd go with a V-8.
  10. Early 4,3s are similer to the V8 the later ones have a counter balance shaft above the cam shaft. I think 98 is the cross over . the early 4.3 the harmonic balancer,timing cover and other parts are V8 interchangable. I have a 99 with a Mercruser 4 barrel manifold (there is a differance in motors as the latter engines have vortec heads) be sure befor you buy an intake. For the dist contact GMC Bubba here on the hamb for his HEI V6 dist. It has the small cap and external coil. Great guy to deal with. PM me if you need more info. I have a powerglide behind mine.
  11. While I like the 4.3, in a pick-up they are definitely underpowered in a pick-up. It's OK in a light car where you're looking for a small engine
  12. zman
    Joined: Apr 2, 2001
    Posts: 16,594

    from Garner, NC

    In real driving a well tuned smaller v8 and the 4.3 will get very similar mileage.
  13. classicdreamer
    Joined: Nov 5, 2009
    Posts: 592

    from nyc
    1. A-D Truckers

    too bad your on the other coast. I have a carbed 4.3 with trans from my project that I may toss in the trash. Cant find anyone to donate it to. Not sure of the condition of the motor but its yours if you want it.
  14. Jalopy Jim
    Joined: Aug 3, 2005
    Posts: 1,867

    Jalopy Jim

    I have a 94 Chev Pickup with that motor and I an real happy with it. Has 236,000 on it and still runs strong, with great gas mileage.

    jim h
  15. blown240
    Joined: Aug 2, 2005
    Posts: 1,654

    from So-cal

    WOW, alot of good into here. I guess I will keep my eyes open for a good deal.
  16. I'm just gonna chime in here and mention that I have seen a few with intake water leaks, including the one in my daughter's Blazer.

    Seems to be common enough that I'd at least pull the intake for a look-see.

  17. blown240
    Joined: Aug 2, 2005
    Posts: 1,654

    from So-cal

    thanks guys. Keep the info coming if you got something to add...
  18. Rudebaker
    Joined: Sep 14, 2007
    Posts: 1,598

    from Illinois

    The balancer shaft started in the mid to late '93 MY. The best ones IMO are the '87-'92 roller cam versions. My '92 S-10 LWB 2WD with 700R4 and 3.08 gears would pull 25 MPG all day long at 65 MPH and ran fender to fender with a 318 Dakota. I drove it like it was stolen and it went well past the 200,000 mark. They have plenty of power in a light vehicle with a 200-4R, 700R4 or 5 speed with 3.42/3.73 and will get good mileage gears.
  19. 35ChevSedan
    Joined: Jul 2, 2010
    Posts: 32


    I have a 4.3 in my '35 Chevy Sedan, was in there when I bought it - nice little motor. I run with the side panels off the hood and it looks fine too. Attached is a photo, and an article I found online that tells all the different changes on the 4.3 since the original one in 1985. Hope that helps!

    Attached Files:

  20. I would like more info on the intake water leak problem . Is it the gaskets or the intake/? where and what do I need to look at? OldfWolf
    Joined: Nov 22, 2005
    Posts: 7,591

    from SIDNEY, NY

    99.9 percent of the time, you just need to replace the intake gaskets. They started leaking on my '96 S-10 after a mere 258,000 miles.
  22. rd martin
    Joined: Nov 14, 2006
    Posts: 2,449

    rd martin
    from indiana

    im a 35 year gm. tech, owned a bunch worked on a bunch, great motor in 3500 lbs or less car or truck, silverados are in the 4000 to 4500 lb range, not enough motor to carry that kind of load and still get mileage. intake gaskets need to be replaced, but other than that, like said before, its a sbc minus 2 cylinders. if edelbrock makes an intake for it go for it with a carb.
  23. fast30coupe
    Joined: Nov 15, 2009
    Posts: 1,019

    from Illinois

    Your not going to get great milage like you think. I had a problem withe the vortex 4.3 in my blazer and my cousin is a mechanic and he told me some of them have problems with crank walk.
  24. wrenchbender
    Joined: Sep 5, 2007
    Posts: 2,115


    Just to put my 2 cents in. I run one in my T with a blower and fuel injection so here it goes. The only reason to put one in your car is because you A you got one or B you don't have room for a v-8. It will cost less to put a V-8 in it trust me I have been there done that. The fuel economy will be around the same one way or the other that is if you drive like a sane person I'm not puttin the 6 down but dollar for dollar the V-8 is less costly
  25. The one's I've seen had erosion on the intake. Of course, these run DexCool, and that could be the whole problem.

  26. low-n-slo54
    Joined: Jul 25, 2009
    Posts: 1,920


    Had one in a 97 blazer. It was in a rollover so the vehicle was totalled but I'll be damned if they couldn't start it up and drive it around the lot when it needed to be moved. Had 125,00 trouble free miles. I honestly never had any problems with it.
  27. Francisco Plumbero
    Joined: May 6, 2010
    Posts: 2,531

    Francisco Plumbero
    from il.

    Heard a lot of guys had problems with the rear main seals in these, had one in a 97 s10, ran nice had 50,000 and a stick, mileage was not that great, about 17 to 20 on the highway, 14 in the city, my buddy had one, his was slow, didnt have the stick, stick was cheaper. haha
  28. Bigcheese327
    Joined: Sep 16, 2001
    Posts: 6,691


    My wife drives a 4.3L-powered S10 Blazer that her inlaws bought new in '96. We had to replace the aforementioned intake gasket a few years back, but all in all, it’s been a good car, and I’m pleased with the power and the economy. I don’t know that I’d want to train myself to work on one after I’d swapped it into a ‘50s car, though.

    If you’re electro-savvy enough to be contemplating an EFI swap, maybe you could work out an EFI system for the 235.

  29. blown240
    Joined: Aug 2, 2005
    Posts: 1,654

    from So-cal

    Hooking up an EFI is no big deal. I just want to get rid of the worn out 3 speed tranny. And for the price of an adapter plate, I will just do an engine swap.
  30. logride
    Joined: Nov 29, 2009
    Posts: 285

    from CB IA

    I've got one in my 27 chevy rod. It's a non vortec motor, came out of a 92 astro van with 156,000 miles. I put gaskets in it got rid of the EFI with a mercury marine intake and distributor, used a quadrajet carb and it works great. I've put probably 10,000 miles on it so far, and it gets pretty good mileage with the 700-R4

Share This Page

Register now to get rid of these ads!


Copyright © 1995-2021 The Jalopy Journal: Steal our stuff, we'll kick your teeth in. Terms of Service. Privacy Policy.

Atomic Industry
Forum software by XenForo™ ©2010-2014 XenForo Ltd.