Anyone running a 4.3?

[crazy longhorn]

My thoughts are that the 4.3 would be underpowered in a heavy truck. if you ever ran a 305 in one of these trucks, you would be less than pleased with the performance. I ran a 305 in a 78 camper special untill I got the 355 done. the 305 then went in my oldest son's 89 ferd ranger.......it runs decent in the little truck! Instead of chopping 2 cyls off, why not add a couple gears to the box? crazy AL

[lukecp]

I am going to have to defend the 4.3. I had one in a '91 S-10, a 4x4, extended cab, with a 5-speed and 3.73 gears. It would move pretty good. It was my first truck, it wasn't very nice, and i was pretty hard on it. It would bark the tires on the 3-4 gear shift. I eventually blew a headgasket at 165,xxx miles from leaving it in first gear for a little long (i was showing off). I parked the truck and later sold it. The truck would get 21-23mpg at 70mph, and it didn't smoke at all before i blew it up. If i would have been a little easier on it, it could have hit 200xxx with no problems. My mom has a '01 S-10 crew car 4x4, with the 190hp Vortec 4.3, and a automatic. It has 3.42 gears. When you hold it in first gear off the line, it gets out of the hole better than my truck. But when you hit second gear, the power drops off quite a bit. That is when i start to miss my V8. I think the 4.3 is a good motor in a midsize, regular cab, 4x4 truck, with a 5 speed. The auto makes the '01 S10 feel less powerful than my '91 was. It would be a little overburnded in a fullsize truck, and that would make the gas mileage drop a little bit. But with a 4bbl carb, RV-style cam, and headers, who knows it might do pretty good.

[brian1987]

Hey,

I am running a 4.3L in a fullsize pickup with a 184,000 miles on it. I paid $2200 for it. It runs strong and gets about 290 miles to a tank of gas.

[cableguy0]

mikep if u wanna keep ur truck y not go and find yourself a little honda that gets 40mpg thats gonna cost u like nothin for a used one. instead of going through all the trouble of the swap because if ur used to a v8 no v6 is gonna make u happy. the torque just isnt there to move these hunks of lead

[weasel29gm]

I've never had a 4.3 so I don't know except what I've been told. They are peppy in a S-10 but I've rode in them and ones with V-8's theres no comparison. 3 trucks with a stock 305, mild 327 and a built 350. All was fast and strong and ran circles around the 4.3 So my point is if you want a gas mileage truck tone down the hi-po engines that I read about. I just don't think a 4.3 would pull 67 -72 and do it justice be cause of the weight. I would rather have a stock 350 with a good sound any day and still avg. 14- 18 mpg. My humble .02

[Project1970]

I agree with cableguy0 - the mileage benefit vs the cost of installing a 4.3 isn't going to be there. If I had a 100mi commute every day, I'd go buy a 35+mpg car - if I had the cash or good enough credit, I'd go buy a TDI Volkswagen...I think they get 40+mpg!

Otherwise...just suck it up. It'd take you quite a while commuting with a V6 to make up the money in gas to offset the inital cost.

[Palf70Step]

Aero dynasmics play a big part in MPG als. As I mentioed earlier My 92 C1500 SWB average about 19 with a best of 25. However my 94 2ED S10 Blazer never got above 19. Same engine, 5 speed, and rear end gears. Big difference was aerodynamics I think, which unfortunately our trucks lack. Also, these engines with the Computer control FI run great, I have never seeam a carb based model do that well. Other than to be different, I like the others don't think it would be worth the money you put in, just to get a very slight increase in the MPG.

[mikep]

[i]. I would rather have a stock 350 with a good sound any day and still avg. 14- 18 mpg. My humble .02 [/B]

Hahahahaha . Show me somebody with a stock 350 in a 4500 lb and 3.54 - 4-10 gears and a non overdrive transmission truck getting 14-18 mpg that doesnt live somewhere where they use imperial gallons ( that lets you canadian and brit guys off the hoook ) I hear about guys on this forum doing just that. I dont believe a word of it. Ive never actually met anyone who gets better than 11 mpg on a regular basis with a V8 and a full sized 3/4 ton.

[68 Suburban]

Its not a 3/4 ton, but my Burb gets 15+ mpg. 350/turbo400/3.08 rear.

[mikep]

OK theres a slight possibility that a 1/2 ton could do it although I wouldnt believe it unless I actually saw it. I only know that my last 69 with a 6 cyl , 3.08 gears and a 3 speed couild only manage 16 on the highway and it was in a hi state of tune. Not that I dont believe you ( I don't ) but the friggin Pope could tell me his suburban popemobile was getting 15 mpg regularly and I wouldnt believe him unless I drove it.

[crazy longhorn]

3/4 ton truck.....forget milage, it wasnt made for that! I have seen 1/2ton trucks with sb v8 knock down 15 mpg......provided that you didnt cruise them much over 60-65 mph on the road. I ran a 71 1/2 ton with a 307, stock cam, & 300hp heads, 3spd stick & 3.73 gears. next combo in the same truck was a 060 over 283 with the same heads, again stock cam, & this one had a m21 muncie behind it.....both ran the same spreadbore holley & got right at 15 mpg on the road. I ran a mild 355 in the longhorn , with a 4spd trans & 3.40 gears...that one got right at 15 mpg on the road. I havent seen that mileage in the longhorn for a while.....the 461 olds got about 7, city or hyway on 3.40 gears. The 383 gets tween 8 & 9......stand on the throttle a bit, & its a gas slurpin MO Fo! All the fun stuff seems to cost....dammit!

[Chevyman69]

I want to defend the 4.3 and this is life expereince as well. One of my former friends has a 88 GMC 1/2 ton 2wd long box. It has a 700R4 and is a cheaper truck, a SLX, so it wasn't terribly heavy. That truck just plain out hauled ass for a V6(TBI), all it had for mods was 3 inch single exhaust with no muffler and just the cat. That thing could burn tires and go like crazy, to boot he got roughly 25 mpg on the highway with it. He had no trouble taking equal trucks with 305's, not 350s but 305's were no trouble at all. They aren't a big trailer puller but in a lighter truck they are kinda fun. I love small blocks as well but those little 4.3's run, I worked and drove that 88 more than the owner did and it was fun. You could take people for rides and tell them it was a 350( with that exhaust it had it sounded like a V8) and they would believe you. In a 3/4 ton no, but a 1/2 ton for running around, it'll blow the doors off those old slow I6's and get better mileage to boot.

[weasel29gm]

Stock 350, curved dist, duals,worked q-jet,muncie and 3.73 posi. Drove around 300 miles a week on 20 gals. You do the math thats 15 mpg. Go south Martinsville or Charlotte always got better unless I started runnin' hard. Laugh if you want done it for years thats when gas was a $1.10-$1.20. Took a K-5 305, 7OOR4 to Texas 3 winters ago and avg was 15-16. Tune em' right and keep your foot out of it, till you need it!!!!!!!

[mikep]

Did you have the right speedo gears in the muncie?

[crazy longhorn]

Yup, had to play with the gears to get the speedo calibrated

[weasel29gm]

Don't know, my buddy set it up.