I don't get everyone who says that the truck is heavier than your car. You even POSTED the truck weight. 2650 versus 3200. 25 mpg sounds like an EPA estimate though, the truck realworlds about 20, my buddy has one, and we get similar mileage. I just filled up, drove 190 miles, 100 highway and 90 stop 'n' go. Will fill up tonight and let you know exactly how many gallons it took, with my 350 TPI Camaro w/ 3.27 gears.

 

LOL my car only goes maybe 240 miles on a tank and take about 13 gallons and thats on a good day. The bad traffic days it gets worse sometimes lucky to go 210-220 on a tank. Oh, and yes my odometer is very accurate

 

Well, I got a chance to really look at 4.3's today .... The oil pans from what I saw could be a real issue since the ones I saw had deeper sump type areas in the front then what my 350 has. I also found the air cleaners to be much smaller in diameter then my 350 so use of my cowl induction won't work.

seems like my serpentine setup will mount to it though but even if it doesn't all accesories are in relatively the same place as my 350. I also found these 4.3's didn't have air injection which is good.

exhaust manifolds seemed to vary considerably from vans to pickups to car. The astro vans drivers side manifold dumps in front of the 5th cylinder like it dumps in front of the 7th cylinder on my 350. the passenger side one appears to be the one that will be a problem but not a big one.

one thing I did notice on all the oil pans it looked like these are not 1 piece rear main seals but maybe just how they are I guess but the rear part seemed to be identical to how the front is where the pan seals on the timing chain cover.

as compact as the serpentine setup is on these heck you could run pipes along side the accesories for twin turbos I believe, they are just not as bulky as the V-8's although I'm not going to do it just a thought though maybe for you twin turbo v-8 guys you could use 4.3 serpentine stuff.

fuel lines could be a issue since on 4.3's they seem to come up the backside of the block.

the heads have ports for my coolant sensor and on other side for my fan sensor however they are in reversed locations might have to extend those wires just a bit so thats no biggy

the motor mounts varied considerably so I think to put it in my car it's going to be a guestimate on what to use. the Y-pipes on the 4.3 seemed to run under the torque converter on all these so that will need to be a custom made thing for my car, because I don't think the way the oil pan is designed you can run the Y-pipe in the stock location again.

radiator hoses will be a problem that I can forsee since my car will require much longer ones, probably not a big problem either.

never saw one with VATS either so might just need a custom chip made to retain this provided the 4.3 uses a 7747 ecm which I've seen they have something else. Never saw a MAT sensor on a 4.3 either.

I still am researching all aspects before going through with this don't worry

 

Okay, since you are determined to use this motor, this what I know about them. As far as the B-bodies(caprices),they got 18-19 mpg city and 24-25 mpg on the hwy. That's with 3.08's in the pumpkin and TBI. I was thinking about buying an 87-90 9c1 police pkg. "AND YES" you could get the 86-90 9c1 police pkg's with 4.3 V-6 and TBI injection. Hp and Tq for these car cars(and the monte as well) was 140 hp and 220 lb.ft. The caprices(whether 9c1 pkg or everyday caprice) with this engine weighed approx. 4100 lbs. The 9c1 V-8 police pkg weighed 4200 lbs. with the LM1 & and LO5 350 engines,
and had 3.42 gears. LM1(carb)/LO5(TBI) hp & tq specs:
190 hp /285 lb.ft. MPG's for the carb 350 was 14 city 19-20 hwy. The TBI LO5's mpg's were 16-17 city and 21-22 hwy. I'm kind of a fan of the 87-90 9c1's, so I did alot research on them. My info is pretty accurate whether it's the V6 or the V8. I hope I was able give you info that will help.

 

Darkride, do you think that those engines would produce better fuel economy in his bird? the car is lighter and more areodynamic then the 2 half brick styles you listed. still great info tho.

 

I also wanted to add this, the early 4.3(84-90) was a loud,unbalanced paint shaker of a motor. It was and still is reliable has hell though. My everyday vehicle is a 01' S10 Blazer LT 4dr./4wd. It's fully loaded,4100lbs.,has 3.42 posi rear,4L60-E tranny and I drive this one like I stole it everyday. My hp & tq with the truck are 190HP/250lb.ft.When I drive like I have since, I get 18-19 city and 22-24 hwy(the best I've done on a tank is 384 miles,90% hwy,18 gal. tank) Driven hard the truck still gets 15-17 ctiy and 19-21 hwy. I would recommend using the 96 & up 4.3's if possible. GM put all the refining they could in the 96-05's. They are smoother than the early 4.3 and they make more power(about the same as a L69 H.O. 305). If you can get a TBI/Carb edelbrock intake for a newer 4.3, I'd say go that route. You will be happier with the newer motor. I'd also check with Moroso. I'm pretty sure you can get an oil pan to fit that motor in your T/A. I also know for a fact that you can get after market headers & Y-Pipes for these motors, they are
mainly for 2wd S10's and C1500 trucks but I'm pretty sure they have something out ther that would work. Check with Summit or Jeg's.

 

Yes, I do think that a newer 96 & up 4.3 would produce better MPG's in
his T/A. I think he should drop in a set of 3.08's or 3.23's and the engine
and parts I recommended. The TBI would hinder a little bit because it's
inefficient(it's old school technology that has'nt changed much since it debuted on the 1976 Cadillac Seville),but not that much. If I had to predict MPG's for that set-up, I'd say 19-20 mpg,city and 26-28 mpg hwy with the 3.08's. I'd say 17-18 city and 24-25 hwy with the 3.23's. This is just my best educated guess. The mpg's could be higher or lower depending on
the state of tune the engine is in, what type of ECM chip is used,the overdrive ratio in the T5(is it 0.73:1 or 0.68:1/that 5% can make
a difference),that is if he's still going to use the 5spd. Believe it or not,
the type and grade of gas he uses could be a determining factor. Wow, I'm
very long winded(lol). Sorry about being so long and drawn out guys. Long
story short, yes his car would get more mpg's. Using the 96' & up engine,
with recommended bolt-ons, I think his bird would have around 200hp and
250-260lb.ft of torque. He'll still be able to have fun and enjoy the car with that kind of power.

 

So you are wanting great mileage, some power, and not much wiring. MMMmmmmmm..... Call me crazy. (Yes, I have been to a psych ward) Throw an Oldsmobile 350 diesel in it. MWAHAHA! Those engines were known for getting 35 MPG on the highway in Caprices, 98s, 88s, Bonnevilles, and some Caddys. It's fuel injected, not electrical, but mechanical. Only about 12 wires to hook up plus 8 for glow plugs. 125 HP and 220 FT/LB. You can get a adapter plate to hook up a B-O-P to a Chevy tranny from Summit Racing. Also replace the headbolts with ARP headbolts, a good headgasket, and a harden oil pump shaft then you'll be good to go.

Just a suggestion.
Also you mention you use to have a Camaro with a 2.5 Iron Duke. You could try putting one of those in out of a S10.

Start the yelling nnnnnnnnnow.

 

LOL I also didn't mention that 4 banger camaro got a cfi motor and a 5 speed dropped into it as well after I was outrun on foot by a bystander laughing at the car......As for the later 4.3 not sure how a referee would really look at it. Guess maybe I could say it was from a 90-92 caprice as long as everything from the 90-92 caprice would bolt to the later vortec engine. See thats one key to an emmisions swap as the engine must come from a newer vehicle then the body it's going into and if the motor is intended to be swapped into a passenger car it must have come from a passenger car .... you can't put a light duty truck engine in a car and be smog legal.As for a diesel ummmmm no that wont happen .....yes I am going to use my 5 speed with the 4.3 ..... as for it's overdrive ratio that I don't know ... however it came from a 1987 Z-28I am going to look at the much newer 4.3 and the possibilities of dropping a older manifold on it to sneek it past the referee. I have heard somewhere along the the way a balance shaft was incorporated into the 4.3 ... probably the vortec version .... anyways can a TBI intake be mounted to a vortec 4.3 V-6?????? Were these newer vortec's a much smoother engine ?????at 190hp and 240ft lbs tq that would be a happy medium I would think. And even at say 150hp and 220ft lbs tq that is in the general vacinity of the cars original LG-4 ..... I do plan on some upgrades for enhanced power like headers and better cam and possibly porting and polishing

 

Hey Jproz, I did some digging and got some more info for you.
First of all, Edelbrock makes a Performer manifold for 87-94 TBI
4.3's with EGR. The p/n is 350-3713, it's $255.99 from Jeg's.
Edelbrock also makes a non EGR manifold for 85-95 4.3's.
That one will probably get you in trouble with the smog police though.
Oh, what the hell, I'll give you the p/n anyway. It's 350-2111 and it's
$61.00 dollars cheaper. I could'nt find anything on oil pans yet, but I'll
see what I can come up with. GM started putting balance shafts in the 4.3
in 1991, and I don't believe Caprices came with the 4.3 V-6 after 1990.
The cool thing about the 84-94 4.3's is that they all look very similar to one another.For example, you could tell the smog tech that the motor is from
an 87' Monte, but it's actually from a 92' S-10. I kind of put down the earlier
4.3's, but don't count them out. Like I said before, the 4.3 is the second best
V-6 GM made. The Buick 3.8 is GM's #1 V-6. If you change the oil in the 3.8
when you're supposed to, the thing is like that freakin Energizer bunny, it just keeps going and going(the damn things are bulletproof,TRUST ME!
I KNOW!!!)But enough about 3.8's, if you can find a 91-94 S10 4.3 and pass it off as a passenger car motor, go ahead and do that. GM even had an H.O.
version of it from 91-94. That one had 190 hp also, but I think that one had
central port FI. With the intake,TBI, and other C.A.R.B. exempt bolt-ons,
I think you will achieve the desired MPG's you are looking for. You could expect to have between 180-220hp and 250-270 lb.ft. of torque with all of the bolt-ons and some minor porting done. If you use the Edelbrock cam,
you might get more. The cam p/n is 350-3714. It's also $255.99. The HP & TQ. claims are ,once again, my best educated guess. So don't quote me
on them, but I have put alot thought into this swap. I dont think I'm too
far off. The lower HP & TQ estimates are for 84-90 4.3's. Well once agian
long winded, but I hope that I gave some more good info.

 

Jproz, this swap has really peaked my interest. I was talking to one of my co-workers about it(he has an 82' 2.8L carb camaro). He is considering
swapping the 2.8 for a 4.3. Keep us informed on your progress. If I think
of anymore info or ideas, I'll let you know.

 

Sure would have been nice to have known from the beginning that you were talking about a 4.3l V8, not a 4.3l V6.

 

He is talking about the 4.3 V-6.

 

Not with a 305-sized bore and 3" stroke.

 

Yes, I'm talking about the 4.3 V-6. I honestly think it would save time and money to just swap in 2.73's or 3.08's, but Jproz is determined to use
the 4.3 V-6. My buddy and I were talking about doing this very swap for his 82' 2.8L Camaro, so I'm very curious to see how it turns out. As long as Jproz
is keeping his 3rd gen T/A on the road, I'll help him anyway I can. A turbo-
charged Iron Duke with a T-56 and 3.23's or 3.42's would be interesting.
Can anybody say SVO killer?

 

I guess I'm trying to read through 65 rambling posts with a lot of non-tech blather too quickly, then.

I still can't imagine any swap of this type being productive toward the originally-stated goals.

 

darkride I would think your friends car would be more complexed as well as more expensive since mines already a V-8 car and all it's electronics can easily rub the 4.3 tbi engine. The 4.3 confusion I take blame for I never realized there was a 4.3 V-8. I am going to retain the 3.73 gears that are in the car and do a step by step comparison of what changes are netting the car. But ultimately I am going to go down to a 3.23 or 3.08 rear. However 3.23 sounds ideal with my 5 speed and should put 65mph right at about 1700-1800rpm. I think I am going to get a later vortec 4.3 V-6 and swap to a manifold I can run TBI on, this way I get a smoother engine. I do plan on retaining my air conditioning so the extra power of a vortec will be better. I'm also planning on upgrading to a nice V-8 aluminum radiator with LT-1/LS-1 twin fans.

 

Jproz, it sounds like you are headed in the right direction.
I have another p/n for you. This one is for 85&up 3.8 and
4.3 V-6's with Vortec heads. It's an Edelbrock Performer
intake, non EGR. The p/n is 350-2114. I did'nt see one listed with EGR. You might be able to modify the 87-94 TBI manifold to fit the Vortec engine. As for my friends camaro, the swap will be real easy. In North Carolina, vehicles 1995 and older are no longer required to go through emissions. All they get are saftey inspections. We're going to drop in a carbed 4.3 without a computer and a TH350 with 2.41's or 2.73's.

 

i had a friend that had a 4.3 in a astro, he put an open air cleaner on it and cut off the cat put a glass pack on it, it got up and went for a mini van LOL, they say a 4.3 was a 350 with 2 cyl hacked off....it was a pretty good motor and had good power for a 6 banger. Would like to see your results of it on here when you finish

 

was on ebay just a short while ago and stumbled across a 4.3 typhoon upper and lower intake manifold. So this has opened my mind to running port injection after I pass a referee check. Now just need some 4.3 T/A decals for the hood J/KThis is just a thought though is all ..... And NO it will never be turbocharged

 

When I do it though I will post pictures of everything involved. I am right now looking for a nice 4.3 if I cant find one then pickapart has a upcoming 1/2 price day and I will snag one then and just have it completely rebuilt.

 

The Typhoon is a light truck. No way a referee is going to accept those parts.

'85-up 3.8 and 4.3 Vortec? Something way wrong there. 3.8 and 4.3 are completely different engines. Vortec is truck-only mid-90's up. There was never a 3.8 Vortec.

I still say this is a completely off-base project, given the originally stated goals. If you simply want a 4.3 in your 3rd gen, that's a different story. But, when you lower displacement and expect to retain power, you are going to sacrifice driveability and economy.

 

five7kid It should have driveability and power. Afterall the 4.3 puts out as much power and almost as much torque as a LG-4 305 & it's equal almost to a LO-3. So I think it should have decent power for what I intend the car to do nowadays. Gearing can compensate for driveability and thats why I'm going to keep my 3.73's at first. Then drop to 3.42 or 3,23's .... I'm not concerned if the car can go 0-60 in 6 seconds or that it can run with my friends vette. Think of this Trans Am nowadays as a grocery getter. And thats why fuel economy is what it needs. I know the "ref" won't accept typhoon parts thats why I said put them on after its smogged. And that gives me 2 years to play around with things.

 

84 and 85 4.3 v6 had two piece rear seals. 86 and newer came with one piece rear seal. Balancer motors like to seize bearing. I had two non balancer motors and they don't shake. The mounts are junk and ground out on the stops. That is what causes the problem. I am on my third set. They last about a year. The tbi heads and 91 to 95 vortec cpi heads have two different intake bolt patterns. No you can't upgrade later, unless you want to change the heads. The edelbrocke intake fits tbi heads only, not vortecs.
No clue what syclones used for heads. Cpi intakes used one injector that looks like a tbi injector and has the same resistance as a tbi injector. The fuel pump is a high pressure pump. They need 42 psi to crack the poppets valves open. They run at 62 to 65 psi. You also have a plenum divider valve that needs hooked up to the computer. The only computer that cares about vats is 1227748 with a camaro prom. If you go tbi, you need a caprice prom, so vats fuel cutoff will be removed. Vats will still control the starter lockout. The motor sit back, so the oil pan will have more clearance. S10 4x4 oil pans are deeper, so stay away from them.
You could swap a 3.1 4 cyl. from an inboard boat. It's a iron duke with a big Chevy bolt pattern for the trans. Use the 2.5 mounts and your tranny. Put a low pressure turbo on it and you are set.

 

when was the 4.3 balance shaft engine introduced? I've been reading on it and it says that that cured the vibrations drastically ... thats one other goal is not to have a noisy 6 cylinder. Also I've come across other info that says some 4.3's had the knock sensor in the block and others in the cylinder heads. Seems to be alot of variations that I want to completely look at before I do this.I'm pretty sure TBI heads will fit a balance shaft engine as well as a TBI intake. This way it will give the referee the TBI caprice look that I need to make all this work and get me the smoother running balance shaft motor.

 

Balance shaft 4.3's were introduced in 1991.

 

Now I've seen a few 4.3 pictures internally now is this balance shaft mounted above the camshaft in the lifter valley? Just curious how well they quiet a 4.3 down, but it does sound like a block that I want for the car if it does indeed make the engine more quiet and have less vibrations. I am going to actually drive a s-10 or something with this engine as well before doing the swap to see how I like the engine. And just kind of research every aspect before going through with it.Anyone know of any other passenger cars that came with the 4.3 v-6 after 90 besides the caprice?

 

My friend owns a ZR-2 S10 with the 4.3 motor. (1999)

The motor seems very smooth and doesnt vibrate any more then any other motor i've seen.

He did throw a rod at 70k. We tore it down and found that one cylinder had completely blocked coolant passages and it had melted the piston. Not really the fault of the engine.

 

I giot this info from a website ...... The Chevy V6 most commonly used a 168 tooth flywheel or flexplate. These do not generally interchange with Chevy V8 flywheels and flexplates due to the unique balance of the V6. is there any truth to this because most say my 153 tooth flywheel will work on a 4.3

 

My monte was a 85 and had a 2 piece rear seal. I used the same flywheel on a 305 2 piece rear seal. The flywheel was a 153 tooth. My truck has a 168 tooth flywheel and has no balancer shaft. The trucks and s10, I seen had 168tooth flywheels. I think cars came with 153 tooth. It's just like v8s. Cars get 153's and trucks get 168s. I think the balancer came with the vortec cpi motors. The tbi did not. Have you seen the balancer? It takes a special timing chain. Just more useless rotating mass to break. The 200 and 229 were semieven firing. They were the ones needing the balancer shaft. Ride in any 80s s10 with a 4.3. It does not need a balancer shaft.

 

I have found a member who did a 4.3 swap (silence22) although he used a Typhoon turbo engine he should have the answers to mount this engine. He claims very lousy gas mileage but hey it's a typhoon engine so that explains that. ....

 

My bird had a 305 tbi and a 5 speed manual trans with 2.73 rear, I never done a swap befor so it took awhile to make it work.
Anyway my brother inlaw totaled his syclone so i bought the engine and trans
and all the other stuff i needed, The first thing i had to do is move the motor mounts back 2".
Not that big a deal, The oil pan was way to deep it hung down way too much.
So i took out 1" in the center of the pan then welded it, The oil pump tube had to be cut and welded as well.,
I had to use the wiring harness and the ecu from the the truck and the fuel pump aswell. My aircond res had to be butchered to make room for the turbo downpipe, Had a few plumbing probs and thats about it.
Now comes emissons, I made a few mods to the engine so when i had it tested i was told that it was illegal to put a truck engine in a passenger car.
But sence GM put them i car in the past they let me slide, But i had to get it back to the way it came out the factory.
You shouldt have that much trouble with the swap, It is a good engine and it is a 350 with two cly cut off. If you have any questions let me know.

 

I would like to know how it performed compared to a V8 car, and of course what gas mileage you are getting, since this seems to be the main theme of this thread...

Some pictures of it mounted would be nice as well...

 

I never thought a V6 would out perform a V8 but it is a turbo, It's very hard to tune and you have to do it often. Im getting about 13 mpg at best but thats not why i installed it. I think it got about 17 or 18 mpg right out of the factory. I have pics on this site.

 

Real world mileage
I have owned most of the engines mentioned, so the mileage numbers listed would be with the same driver. All figures are at hi-way speeds. All cars were burning gasahol, 10% ethanol, 89 octane.
*83 Firebird 2.5 4 cyl iron duke, TBI, 4 speed, stock axle ratio. 25 mpg at 65, air off, windows down. (Almost changed to 5 speed for more mileage, but traded it off.)
*85 impala 4.3 V6 TBI, 3 speed auto with lockup convertor, very low axle, about 2.56. 20-22 mpg at 75, air on, windows up, 4 passengers and luggage (still own, 190,000 miles, motor does not vibrate)
*86 Firebird TransAm. 305 TPI, 700R4, 3.27 gears, stock convertor. 18.5 at 65, air off, windows down. **Changed to 406 TPI with small cam, went for all torque, and has complete emissions equipment. Did add headers and hi-flow cat. 20.5 mpg at 65, air off, windows down. That's with a 2200 stahl convertor and chip from 305. Changed chip to custom, same mileage. **Changed to 1900 stahl, mileage up to 24 at 80 mph (2200 rpm), air off, windows down. Changed rear tires from 245/50R16 to 255/50R16, mileage up to 25.

I think the 4.3 would be great for you. Just watch the parts you choose. I wouldn't rule out the 3.8, the most developed engine GM has. It's been around a long time, and gets great mileage. I did use Desktop Dyno for my 406 to get the power curve where I wanted it. The program may not calculate the numbers correctly, but when comparing engine to engine, cam to cam, or heads to heads, it calculates it wrong the same each time. I put numbers thru the program for months comparing head and cams. When I called COMP Cams to get their recommendation, we had a difference of 6 degrees duration. Use their help. I told them exactly where I wanted the power to start and stop. The car was dynoed, and the power was exactly where I told them I wanted it. Good Luck, we are all watching to see how it turns out.

 

I was considering doing the same thing for a while, but I'm considering alot of things. What I'd like to know is if there's a way to get a little more rpm out of a 4.3. Maybe it'd be best to use a 3.8 and 4.3 intake and heads. I wish someone knew if the 3.8 vortec heads fit on the 3.8 buick. I have 3 of them.


Either way, sounds like an interesting project!

 

4.3 heads and intake may fit a 3.8 Chevy block, from late 70's/early 80's (distributor in back like 4.3) but not a BUICK anything. The 3.8 Buick (now 3800) shares not one interchangeable part with the 4.3. They are completely different.

 

4.3l could be found in as early as 84 caprices, impalas and montes. I spcifically owned a base model 1985 (iirc) Monte Carlo LS, the computer was on the drivers side, behind the kicker panel, and was bolted to 200R4 with LSD. Another engine you might want to look into is the 4.1/4.3.

 

Necromancy