Wimimc

iTrader: (2)

so i've been thinking of engines to swap into my S10, it would be a daily driver so fuel economy is by far more of a concern than power.

i rarely drive on the highway, and when i do its not for an extended period of time so i'm mainly looking for city mileage.

the truck is a 95 extended cab S10
3.08 posi
5 speed
weighs about 3300

i've been thinking bout swapping a newer ecotec out of a cobalt or cavalier into it but i've just started thinking about a gen III motor.

so what kind of city mileage do you think i could get out of a 4.8L? heck even a 5.3?

71novaguy

iTrader: (2)

I dont think it would get much better than the 5.3, but it sure can't hurt. I have the 4.8 in my 07 silverado extended cab, standard bed, 2wd, and with 3.23 gears it gets 16-17 in mixed driving, best of 22 on the highway. In your set up, I could see it getting a solid 18 with dips into the 20's if the city driving your talking about isn't constant redlights and speeds of 30-45 mph most of the route.

I may be the only one on this, but I would be curious if you wouldnt benifit from a little deeper gear if all your doing is city driving. Keep you in a more constant power band and keep it from lugging. This would depend on what rpm you are usually at driving speeds.

Wimimc

iTrader: (2)

not constant, but there are a fair amount of redlights, depends on if i get lucky or not, and speeds on roads can be anywhere from 30-50, typically the speed limit being ~40-45

i would be babying and trying to shift ~2000 rpm as much as possible, and depending on the speed i'd try to keep them 1000-1500
And if i had i to i would swap a 6 speed in.

what number gears are you thinking?

cali_bear2003

iTrader: (7)

What happened to the original motor? If the original engine is in need of a replacement, I would just replace the 4 with another 4 cylinder due to fuel consumption. I have 2 S10's and both have the 4.3 V6....its a thirsty beast.

Wimimc

iTrader: (2)

haha it has the 4.3 in it, the vortec with the CPI

originally i was looking for a 2.2 but this truck had everything else i was looking for

and so i'm thinking i can swap in an ecotec and drop 50 horsepower and a fair amount of torque, but gain substantial mileage, or swap in the 4.8L and get a little better gas mileage (hopefully, if i see 21-23 i would be extremely happy) and much more power.

JohnS Z28

iTrader: (1)

oh i had a 4.3 vortech in my blazer and was getting...well more than i get now HAHA.
I was doing...GOOD city driving? not many lights and the speeds of a couple roads were 45-55 and the lowest was 35, and if i got lucky i didnt hit many lights.
I probably got 20 MPG...because i defiantly noticed a changed in my gas bill once i bought this... I probably get 18 in my z28.

anyway...4.8 in a s10...maybe high teens, low 20s is reasonable, but kinda unlikely.
5.3...high teens

cali_bear2003

iTrader: (7)

Well, both of my s10's are the 4x4 models. I have one ZR2 which I recently took out on a long trip. I had my cruise set at 65mph and my BEST on the road was 18.5 MPG. Granted, I have 31 inch tires and 3.73 in the rear, but the 4.3 is certainly a thirsty. My other is also a 4x4 with the standard 235/75/15 tires, but it is also running a 3.73 rear. My best around town and this is while driving like a dying snail is 17.035 MPG. I always let up at 2000rpm and let the trans grab the next gear for maximum mileage, but this is all I can manage myself. I also have the 4l60e trans in both trucks. I hope that others with the 4x4 drive is actually getting better consumption then me......the 4.8 will drink more....but sound Way Better out back!!!

Wimimc

iTrader: (2)

you really think that the 4.8 would drink more? i mean with my LS1 i get 18-19 consistently, and thats the a 4l60e and 3.23 gears, i figured that the 4.8 being smaller and behind a 5 or 6 speed would yield some better mileage

71novaguy

iTrader: (2)

the 6 speed would be overkill for what you are doing. I suggest taking the tire size, gear ratio, and the gear ratio of the trans and putting it into a rpm calculator. Find out what combo gets you around 1200-1400 rpm at 45 mph if thats where you typically find yourself driving. That would keep you from lugging it and allow you to cruise at a low rpm. that should result in some good mpgs

Wimimc

iTrader: (2)

hm with my 5 speed trans, 3.08 rear, and tires (27")
45 @ 1259
65 @ 1819

if i go with 16 inch rims but a smaller sidewall

29"

45 @ 1172
86 @ 1693

does that sound right?

71novaguy

iTrader: (2)

Id stay with the first combo.

1999 SS

iTrader: (3)

i bet youd get a lot better milage with a 5.3 or 4.8 v8 then you will from your current 4.3 v6 then you think. a big engine moving a light load is more efficient then a small engine moving a big load and in this case for a v8 your 32-3400lb truck is a light load.

Wimimc

iTrader: (2)

thats what i'm thinking, these trucks and SUVs getting ~16-17 city (which is what i'm getting with the 4.3 right now) are at least a thousand pounds more than me.

kinglt-1

iTrader: (26)

This!!!

JimsWS6

iTrader: (1)

Theres lots of fairly inexpensive bolt on's you can do to the 4.3 to get better mileage. Electric fans, and UD pulley top the list. And I know everyone thinks 3.08's will give you better mileage than say 3.42's or 3.73's but I've proved this theory wrong on my S10's. I'd dump those.

Wimimc

iTrader: (2)

i definitely plan on doing the electric fans and tuning it.

i noticed that about the gears, idk if its that or the transmission, but in my camaro 4th + 3.23 gears is at a lower rpm than 5th + 3.08 on the truck

Fry_

I've seen proof of this first hand when 6 or 7 years ago my dad traded in his 95 GMC 1500 2wd standard cab long box, with a tbi305, and 5spd that got 18-19mpg hiway, for a 2000 GMC 1500 2wd standard cab shortbox, with a 4.3 v6, and a 5spd and dropped to 16-17mpg hiway. A small motor in a heavy vehical has to work to hard. then add the more efficent efi setup, more advanced computer, more efficent combution chamber, and coil on plug ignition, and I don't see how you couldn't gain mpg if you keep you foot out of it, and around town I could see you gaining mpg with 3.42 or 3.37 gears with either motor and more so with the 4.3 be cause you'd lug less. I also dout there would be much of a milage difference between a 4.8 and a 5.3

JimsWS6

iTrader: (1)

you want a V6 to be 1800-2100 rpm at 60 in OD. 1800 for 2wd, 2100 for 4wd's. I've seen charts online before about this, stating the same thing. But all of my S10's are 2-2200rpm at 60 with the gears i have in them. Great performance and fuel economy for what they are.

Danny Bradley

right now I’m the city I get like around 13 mpg and that’s with shifts never going over 2000rpm but on the highway I get around 20-22 doing 80 and 2,000 rpm. And any recommendations for gears once I build my 4.8

98ws6blk

From a strictly financial perspective, you can buy a lot of gas for the cost of doing an LS swap.