LUVTruck.com

After extensive research, i finally found the year for the 4.3 i got from my uncle. I found the number 14088553 on the rear of the block. Does anybody know of the max bore specs for a 1986 Chevrolet 4.3 out of a C10? I have the engine now, and it was in pretty rough shape. The combustion chamber had a nice ridge on the top and i took it down with the ridge reamer. any and all info on this motor would be great!

Its basically identical to the same year chevy 350 minus two cylinders so that should make finding specs easier. Lot more listed for the v8 . I think people usually avoid going beyond .060 A common overbore and most common piston size is .030 over which mine has, mines a 91 block that was in horrible shape as well cylinders were tapered .015" was gonna go .020 over but .030 has way more pistons available.
I think 86' is when they converted to the hydraulic roller cam and one piece rear main seal so u may have them.

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Luvless
1980 Mikado-Sold.

1993 Lexus SC400 my Daily
2004 Yamaha WR250F my new love in life
2016 Toyota Camry my girls ride

Where did you find all the parts? I'm in college and am currently rebuilding it the the shop on campus. So pretty much, that means not a lot of money to spend lol. I have a backup 4.3 just in case its gonna cost too much, but im hoping that this one will work out!

i know the feeling I have spent basically every spare dollar on mine since I bought it but I went way overboard with aftermarket parts on mine
you can get a rebuild set with everything but valvetrain (cam, lifters, rocker arms) for around $250 on ebay I got a enginetech brand rebuild set for mine, you can also check out rockauto for anything full rebuild sets to misc little parts. summit has lots of parts for them as well... the compatibility of the smallblock parts makes it easy to find good deals and you get two spares if u get a v8 set.
the 4.3 can use almost all parts from a 350 of the same generation, EXCEPT connecting rods, and the bearings from them because the v6 crankshaft journals are a bigger diameter because of the offset to make the engine even fire, you will notice the mains aren't centered from each set like they are in the v8 when you take a look at it.
if you have any questions about the 4.3 feel free to pm me I have ran thru a lot of the info and did a ton of research during my build.

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Luvless
1980 Mikado-Sold.

1993 Lexus SC400 my Daily
2004 Yamaha WR250F my new love in life
2016 Toyota Camry my girls ride

You might be right but I thought 88 was when they converted to roller. Personally, I would have preferred that block because if you go really wild with the cam or go mechanical roller the lifters go into the lifter bore so far that wheel on the roller lifter opens up the oil passage and the pressure drops. They sell a lifter for "small base circle cams" that helps but without a high volume/high pressure pump it doesn't help that much. The mechanical flat tappet on the other hand can be pushed all the way into the lifter bore and never eencounter this. Another plus with the older block is they are internally balanced.

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Fortune favors the well prepared!

Ditto

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Fortune favors the well prepared!

The big question i have at the moment is would it be worth it to bore and sleeve it back to the original? or should i just leave the cylinders as is and run it like that? The chambers are worn a bit and I've heard different opinions.

You'd be better off getting another block from a pick and pull or even ebay. It really depends on what your goal is. Do you want a nice power plant that will last awhile or a race motor or something that will get you by for awhile. Love4theluv did a pretty nice build on one that will last quite awhile and has some nice power. He conservatively estimated it at 250 but is probably more in the 300hp range and not to high revving. Check out the video on my build, 74 ultimate sleeper, and you'll see just what you can do with one of these. Mine spins 7k. If you have the stock rear end and aren't planning an overdrive than something that lives in the higher range will be more desirable. If you have changed the rear or the rear gears and are running less than 3.73 than you'd be ok with one that lives in a lower rpm band. At any rate I wouldn't sleeve it. Too much trouble and cost when there are easier ways to get back to stock 4" bore. If you really want to go all out and money isn't a problem than there is a guy selling scat stroker cranks on ebay. But once you go down that road everything is custom built. From the rods to the pistons to the heads to the main caps to the intake. I spent around 5k on mine and could have easily doubled that and put down 500hp. If I want 500hp I would just build a destroked 400 sbc and spin it @ 9k making 750hp. Would cost a little more but man what an engine. If you tell me your budget and what type of tranny and rear end I can line out a build for you.

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Fortune favors the well prepared!

Really, its just gonna be a cheap build. its gonna be one of those long term projects for now. My budget is around 500, which is a terrible budget, but the motor and tranny were free. i think im goin to talk to my uncle who has another 4.3 to get that one instead.

Yeah for 500 you would be better off trying to get one that is running in a donor vehicle. You should be able to find on CL but then will have to gather up a few more bucks for a carb, intake and dizzy. Good luck and you should post some pics of your truck.

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Fortune favors the well prepared!

Finally got the 4.3 rebuilt! Took me long enough and I managed to do it pretty cheap. Well with the 500 budget. My issue now is what engine mounts to use. The motor that got rebuilt was from an 85 Chevy c10. Will the mounts work on the luv? Also, does anyone know the wiring of the carb? I have a Rochester 4bbl and am trying to hook it up to the stock luv harness for the car. It has a blue, black, black yellow, and black white wire. One is the choke, but idk about the other two. Another thing is I'm putting in an th350 tyranny behind the motor. Do I need to do anything to the rearend (besides lose the stock gears! Gonna do that anyway!)

powerbyace.com has the adapters to mount the 4.3 to the stock mounting pads. Headers too.

yeah I used the power by ace mounts but ended up modifying them to sit the engine where I wanted it, out of the box they will work tho

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Luvless
1980 Mikado-Sold.

1993 Lexus SC400 my Daily
2004 Yamaha WR250F my new love in life
2016 Toyota Camry my girls ride

FYI The 4.3l engine is 4.4 inches shorter than the SB engine. All behind the engine mount position.

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The light at the end of the tunnel, may just be a train coming!