We know mileage is not great with a 4wd truck but why should I/we drive an S10 if a full size truck that weighs more, makes more power and get the same mileage?
I feel a lot was left on the table with these light trucks and it would be interesting to know why.

 

The full size is either; newer; more aero; slower. Multiple choice answer

 

For me it is the smaller sized truck a) fits in my garage with room to walk around the vehicle, 2) fits into smaller parking spots (closer to the doors) and gets fewer dings from other inconsiderate drivers, 3) the smaller interior cools quicker and warms up quicker. and there are reasons I have the smaller vehicle.


I know these are not on everybody's priorities. Just saying mileage is not the only consideration for choosing one vehicle over another.

 

What seems funny to me is those who install a swing away spare, lift the body, put a roof basket on top, lift the suspension, put ZR2 fenders on the side, and 33in tires with less backspace, then want better milage. Sheesh, just get a bigger truck WITH IT'S BETTER MILAGE.

 

Mileage

 

Not looking to pick a fight. There are always compromises for every choice we make. Don't worry, I am looking for a different vehicle.

So I had a plan for a build that I thought could be pretty good for a road and trail rig.
2000 L67(supercharged 3800) out of a W-body. Rated at 240hp/280lbft with 18/28mpg vehicle weight ~3455lb
2001 S10 4.3. Rated at 190hp/250lbft with 16/22mpg vehicle weight ~4049lb

So the W-body has 26% more Hp, 12% more Tq, and 17% less weight.
The W-body is 14.4 lb/hp ratio, Blazer is 21.3lb/hp and if you swap to the 3800 in the Blazer you'll have 16.87lb/hp. In other words it ends up with a lower power to weight ratio than what the 4.3 makes.
There will be a trade off in low end torque though. So if anyone is interested in a truck that will smoke the tires and pick up 4mpg highway you can give it a try. Best part of all you get away from the failure prone injection methods they used on the 4.3. There is a catch as far as a bunch of harness splicing, running a different fuel pump and either a bellhousing adaptor or else switching to the 4L60e that came in the 4cyl S10 and converting it to 4wd if needed.

 

You seem to have done your homework well enough, unlike several others. It might not be in your area but around here an older motor cannot be installed in a newer vehicle. EPA reg

Just as a humorus note there is a thread where a guy fell asleep at the wheel and went belly up, and his answer to the catasthrophy was crank the T bars and install a 2in body lift. Ya just gotta love Blazer Forum

 

Simple physics is the biggest explanation for mileage numbers. The biggest reason for the W body's better city MPG, (18 vs 16) is the weight. It takes more power to accelerate the larger mass. 4049/3455 = 1.17 or 17% more gas to accelerate. since the city is not 100% acceleration, the actual numbers may be about 1/3 the difference or 8.5%. the difference between 16 and 18 MPG is about 12% more fuel consumption. At road speed, aero has the biggest effect on MPG, not weight. It is easy to visualize that the Blazer body is quite a bit less aero efficient than a W body. Some quick numbers I found are the '95 Lumina has a CdA of 6.96 and a '92 chevy Blazer has a CdA of 10.7. 10.7/6.97= 53% higher drag. Which one do you think will get better highway mileage?


There are a lot more factors to consider when figuring expected mileage. However, generally speaking, a bigger engine will almost always give lower mileage not higher. Don't believe me? Take a look at the same vehicle with a 4 cyl and a 6 cyl engine , such as the S-10's. in the case of the 3.8L the engine is smaller and might get a bit better MPG if you can keep the supercharger from increasing the effective volumetric efficiency.

 

I guess it would almost come out as a wash after aerodynamics are factored in. But I still hold the Ace on the EFI sucking on the 4.3.

 

Absolutely no argument there, my friend. Whoever thought it was a good idea to bury the injectors inside the engine (either style) ought to be drawn and quartered. And his boss who approved the design out to be next.