thinking of running one in the 46...are some years better then others...what crank ,cam,heads ect...he has a turbo setup, are they any good...i just gots to know!!!!
i personally dont have anything good to say about the turbo 4.3 i had nothing but breakage melted a piston, broke a crank 2times,no valve seals on the exhaust you wil have to add them if you dont want smoke the more power you try to get out of it the problems (91 to 93)
4.3 V-6 or 4.3 V-8? Chevy made both. For the V-6 variety I recommend this site. You'll find everything you wanted to know there. Great motors, it's "basically" a 350 with 2 cylinders lopped off with a few unique differences. http://www.fullthrottlev6.com/forums/forumdisplay.php?f=66 The V-8 is the L-99 used in the 90's caprice, also known as the "baby LT-1". It's basically a 1 Pc. rear main 305 block and pistons with a 3" stroke crank and 5.94" rods. You can use the crank and rods with a 1 Pc. rear main 350 block and pistons to build a 302 but I wouldn't recommend trying to rev one like the 302 Z/28's.
i have a 4.3 motor in my dads 38 gmc pick up. it rans and drives good .i also have a 4.3 in my van i drive and it gets good gas mileage and has some good towing power.thanks
Check out a couple of articles from Hot Rod a few years back... 3/4 350 500HP from 270 CI The Vortec heads are better and Edelbrock makes a carbed intake for them. Use the '85-'92 block without tha balance shaft.
Sounds like you needed a lot of help with the tune. Melted pistons is a direct result from running lean. Two broken cranks? You were either making over 550HP on a stock crank, or once again your tune was horribly bad causing detonation and resulting in broken cranks. no valve seals? I'm ***uming you are referencing the puff of smoke on startup?? I'm not sure why yours didnt have valve seals, they were there when they left the factory. Yes, they do leak over time/mileage, but they cost practically nothing and certainly dont cause much problem other than a little smoke on startup. If your engine was smoking that much, Id say it was due to an incorrectly plumb'd PCV system. Yup, anything over 550 at the crank and you run the risk of problems. Nitride treating does help, but a billet crank is the best option. Unfortunately for the cost of a 4.3L billet crank, you could have a decent short block SBC. As for the 4.3L's in general. 96+ have the best flowing heads. The block, intakes, pan, covers, ect will not directly bolt onto 95 and older blocks. the pre-96 heads came in 2 basic versions, LB4 and L35. The L35's have been known to flow betters stock as well as in ported versions when compared to a LB4 head of their equal. Blocks and cranks are pretty much all the same in terms of strength. L35 rods are also known to be slightly stronger, but not sure by what numbers. A decent set of aftermarket H-beams can be had for $375 anyway. When it comes down to it, you can built a SBC for probably half the cost of a turbo 4.3L and have an easier time tuning it.
I had a 94 s10 ss with a vortec 4.3 motor ran really good ,amazeing power and excellent gas milage. Had 110000 on it when I sold it.The motor ran fine but it was ****** #3.
Great engines...I bought new, and currently still own an '89 GMC sierra short bed regular cab, with a 4.3 trottle body, backed by a ****ty G.E.T Rag 5spd. 457 837Km's and no problems since it was new. I live in Ontario, but all my family is from Alberta, and that truck gets me there 2 times a year (about 3600km's one way).
I've built a couple of them. OK engines if you like V-6s, but no matter what you do to it it's still gona be a V-6. I recomend early motors for simplicity. Edelbrock manifold and carb. you can use the 85 distributor. good street cams are hard to find as they mostly make drag race or RV cams with not much in between. I found a Crower grind that worked well. don't have the number in my head, but there's only a couple. mine put out ~ 280 HP and ran well......... but it still sounded like a V-6 . OC BTW. I have a stock 2000 Blazer and it gets 18-19 MPG. not what I would call stellar mileage engines.
I have rebuilt many of these 4.3 and I think the 96 up are the way to go. Only the 96 and up are true Vortecs. Around 2002 they added roller rockers and made the 4.3 even better. Eddelbrock makes a manifold for the 96 and later 4.3. I have the factory cam reground to a LT1 spec. I have built at least 20 of these and had some go into boats as Mercury uses them. Van
I've heard the later ones didn't get the best mileage, too bad because the early ones did pretty good. My old '92 S-10 4.3 TBI, 700-R4 with the optional 3.08 gears and 215/70-15's averaged about 24-25 with a best of 26. It had good power too, the 3.08's helped over the base 2.56's. I sold that one with 157,000 miles. Didn't use a drop of oil and the underside was squeaky clean. Love those 1 Pc. rear mains! The kid that bought it beat it around here as a farm truck and back and forth between Illinois and Colorado several times for a couple years. Just about every time I saw it he had it loaded down with the back bumper almost dragging. I heard he finally killed the transmission. I had a 3 year old '85 Monte Carlo with a 4.3 TBI (flat tappet version), 3 spd. auto and 2.29 gears. It could pull 28 on extended freeway trips, couldn't p*** it's own shadow though. It was still around the area a couple years ago. The current owner was a friend of a friend and stopped by to show me the new paint job. It was smoking pretty badly but she told me it had just rolled over 300,000 miles! She loves that car and said she'll keep it forever. I believe her! Her next step was to get the 4.3 rebuilt. I recommended she find one of the newer roller cam versions. If that car had come with a 200-4R and some decent gears it would have been a really nice combo. I have 3 roller block 4.3 cores, a 200-4R and some 4.3 aftermarket goodies....... Comp Cam 260AHR roller, TRW pistons, Edelbrock Performer, etc., I may just put one together one of these days.
I see alot of these with a rod knock. The oil cooler lines fail and b4 you realize it, it's too late. If you are looking at a used one, just be aware of this. I currently have a 98 and the lines had to be replaced in 2001 due to leaks. I caught this one in time. Other than that I like these motors. Just my .02
I would say 1995 was the worst year hands down. The fuel injection spider probably had the most problems ever this year, its also the year of the *******ized OBD 1.5 system. The rod knocks seemed to be more prone this year as well, you find a ton of 95's on Craigslist with engine problems. As someone mentioned about the roller rockers, I have a 2000 engine I bought for parts, it had the full roller rockers on it, so I'd venture to guess that was the first year. I'd personaly used a Pre-96 Non-Balance Shaft block with '96+ heads ('00+ if you want the stock rockers), Edelbrock carb intake for 96+ heads, decent cam, ect ect. If I was going forced induction with fuel injection, Id probably build it similar, just with low compression pistons, weld in injector bungs into the Edelbrock intake, throttle body that mounts to the carb flange and do a stand alone computer system like Big Stuff 3.
I had to replace both oil filter lines on my 2000 last year also. I had a shop do it (hate working on stock, newer vehicles) and he mentioned that most of the FLAPS have the lines in stock, so ya, it must be a very common problem. With the filter located above a big plastic shield behind the radiator, it's easy to check used vehicles for leakage however as the shield will hjold a Quart or so
Capt Morgan I have a 1991 s10 blazer it smoked on startup ck tsb the was one for installing valve guide seals on exhaust and up dating intakes fixed the problem. It has 282,000 miles on it.I run spark plug gap at .060 and advance the timing 5 btdc and get 18 to 20 mpg in town.It has auto a/c power windows and door locks 2wd and 4 door.
No complaints about the 4.3 in my '96 2WD S10 parts hauler. It just turned 293,000 miles, still doesn't use oil, and the furthest I've been into the engine is replacement of the intake gaskets. Good power and always in the 23-24 mpg range.
I'm putting a 94 S10 4.3 and 5-speed in a 40 p-up now in what I would call a late 50s early 60s style (looks wise). I don't know when it will be done but so far I'm enjoying the project. It will be my shop truck/daily driver. I have an early intake and it will run a carb, I'll keep the serpentine belt system, I placed the motor to use the stock S10 driveshaft, Sag PS, PB, 46 Ford heat/def unit, AC unit under the 96 Mazda MPV 3rd seat (fits perfect), 66 Mustang radiator, stock column w/40 Std wheel, and it's all going to a 66 Mustang 8" rear w/either 3:40 or 3:50 ge****t. I will also have a Cl*** III hitch and air shocks to perhaps pull the 32 in my avatar - we'll see. I did have a 91 Chevy Silverado SB w/4.3 and 5-speed. Smoked on startup only but always ran nice. Never touched it in the 2 years I owned it other than to change the oil. Why am I using it? Price, condition of the combo, something a little different, has PS, AC, alt in a ready-to-go package for the wife who should be able to hit the key and go anywhere she wants with it as she loves driving a stick shift. The S10 forum is also another great place for info ....
i have put a couple of 4.3 v6s in old cars 39-54s and they work perfect for daily drivers and more then enough power for everyday use the only thing is that that i change the distributer to an hei and change the fuel injection to a carb
I had a 91 S-10 pickup and i hated that damn 4.3. 9 miles to the gallon on the freeway, and couldnt get out of its own way. Computer was screwy and the fuel map was all over the place. ****** didnt lock up either. Wouldnt rev high, and had no power. That one got the crank case filled with sodium silicate. Good ridence!
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