4.3L to ?? swap.

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DeCaff2007

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sorry slight thread hijack,,,, another interesting thing about them malibu's, all had, you guessed it AC.
the V6 was a 3.8 IIRC.

No worries! I always find it very interesting to see where threads like this can go. Good reading, indeed :smile:


So, here's my options/thoughts so far. I don't need to burn the tires off at every traffic light. This trucks primary purpose in life under my ownership is a secondary daily driver/transportation to work in the winter.

Granted, the 4.3L was probably a decent engine back in it's day. But IMO, this truck needs a period correct V8. A 5.7L seems to fit the bill the easiest, because that's what's meant to be under the hood. Not an LS, not an LT1 (although, those are no slouch, either) Actually, a Buick 3.8L (NA or SC, doesn't matter) is a pretty damn solid engine, but that would be a sh1tshow to make it work.

With that: I have an 83 Grand Prix waiting its turn (now THAT'S an LS swap candidate!). It's a V8 5.0L, but with a little TLC (and a fuel-injection conversion), it could also fit the bill. That's a no brainer, eh? Pull the TBI V6, drop in a carb'ed SBC, and now convert that to FI. Oh, and that's a CCC (computer controlled carburetor), at that. Maybe not worth the effort for a 5.0L

Here's what I'm likely going to do: I've never had a crate motor and I want to drop one in. My biggest issue is getting a STRAIGHT ANSWER on what to do about the computer that's already in the truck? The most common answer I've read (and it's a vague answer, at that), is find a junkyard computer that matches the engines displacement and the rear gear ratio. Get it flashed. Actually, "flashed" is the incorrect term here. To flash a computer, or any EEPROM, means to ERASE the data that's already on it, leaving it blank. It would need to be programmed afterwards, so:

WHAT IS THE POINT OF PROGRAMMING A COMPUTER IF IT'S SUPPOSED TO ALREADY MATCH? That, and junkyard electronics are a crap shoot. No way to know if they work.
 

Jeepwalker

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The junkyards around here are full of OBS trucks. There's got to be some yards in your area too. Hard to imagine you couldn't find one the same year as yours for a 5.7 and same rear end. IDK if they even used a different program for the rear diff. There's a bunch on ebay too.

Won't a $350 knock-off Tech-1 scanner do the reflash?
 

tayto

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I used to have a '81 Malibu with the 267, it was totally gutless but it had a THM350 trans in it already at least. I built a 355 out of mostly junkyard parts for it when I was in my pre-apprenticeship program. That really woke it up, but it was dying for some better rear end gears. I think I had 2.73s or something. My dad was telling me (after I got that car) that GM made a bunch of them with the V6 and a 4 speed manual trans, most of them were exported to the middle east. That would have been a cool base to start with! Well, I'm just partial to manual transmissions.

To the OP, I've also got a 4.3 begging to be replaced in my truck, and I've been mulling over the options. You could always just swap in a regular old small block and change to a carb'd setup, if you are averse to wiring. That way definitely has its merits. Honestly the LS swap is the way to go though, plenty of people have done it, it's not difficult to figure out. There's so much aftermarket support for these swaps, and people put them in literally any kind of vehicle you can imagine, so it's not a difficult thing to do. Odds are you could probably find someone near you who could get it done as well, if you don't want to tackle it yourself.
they were actually 3 speed manual and had AC and basically no other options. we call them "iraqie taxis" here in canada. the story goes they were suppose to goto the middle east but didn't and sat at a dock yard in eastern canada for a year. they then had some emissions stuff added to them and were sold at 1/2 the price of an '82. i had 2 friends that each had one, gutless but still a neat piece of history. unfortunately most of them have dissolved at this point mainly because they stayed in eastern Canada (they salt roads heavily in winter) but i occasionally see survivors. they have gone up in price like everything lately. in highschool they were a $500 car all day.
 

DeCaff2007

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As much as I'd like to say I'm getting started on this engine swap... life is getting in the way again. I still haven't finished the Wife's Jeep. That 3.7L is THE most difficult engine to line up to the transmission when reinstalling. Finally got it to line up and got a few bolts threaded in just tonight. No time after work for anything but dinner and bed, let alone time to myself or to get anything done.

The friggin swampy muck humidity hasn't helped lately, either.

Now for the EFFING STELLAR news /sarcasm.... A friend of my Wife's pulled into my driveway unexpectedly in a 2000 Toyota Camry and said, "How much to fix it?" I should have told the Wife's friend to get bent. Instead, $600 in parts later, it will have an all new exhaust. I about had a stroke when I saw the price of a catalytic converter for a 4 cylinder Camry. Luckily, it's all bolt on and can be done in about 2 or 3 hours, as soon as the parts get here.

There's so many POS cars in my yard right now that I'm going to hang a sign in front of my house that's says "DeCaff's U-Pull It", LoL!

P.S.: I shouldn't complain. Back in early 90's, my Father had a 1984 Chevy Celebrity with a 2.8L fuel injected V6. Ran excellent until one day it didn't. Crank but no start in the parking lot of a strip mall. My Father is NOT mechanically inclined, (and I was maybe 10 or 11 years old at the time) so he calls his expert mechanic/coke head/chain smoking friend. The ignition module in the distributor flat died just like that. Coincidentally, there was a Parts America in that strip mall. $50 fcking dollars and 15 minutes later, we are back on the road. Maybe that's pocket change for some people, but back then, that was A LOT of money for my family, hence my cheapness today.
 
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