worthwhile putting a 2.0 into a 3500 lb '85 Monte Carlo?

[s2man]

Back in the late 70's, I converted a 360cid (5.9 l)engine, in a full size pickup, from a V8 into a V4 (2.95 l) for FE. Ugh, what a waste of time. Acceleration was non-existant; I had to plan lane changes on the highway miles ahead. It started burning oil. And I only got about a 10% increase in mileage. I'm sure different gearing would have helped, but there is a reason they don't put 4 cyl. engines in huge vehicles.

I second OdieTurbo's suggestion to just put the money toward an economical car. In fact, I'd be tempted to slap another V8 in the Monte, sell it to a hot-rodder, and put that money toward the new car too. :-)

[Telco]

I agree also, sell the Monte and get a car designed for it. But if you insist on keeping the Monte, what engine does it have in it now? There are things that can be done to improve mileage on the car, mainly work on improving low end torque and try to move the torque band as low as possible, then adjust the rear gearing so that the engine is kept on the low side of, but within its torque band. When done, should be able to accelerate easily in high gear without downshifting.

Three examples, my dad had a 3.8L in a 99 Grand Prix, dogging the crap out of it got about 29MPG, driving it easy got 35MPG. The 97 El Dorado ETC he has now gets 25 dogged, 30 easy driving. My own vehicle, 82 El Camino with an engine built to maximize low end torque, was getting 20MPG when dogged hard, with a 3 speed and carb. It got 20MPG regardless. With fuel injection, overdrive trans, headers and the properly geared rear end, I bet that car would have been even faster and netted over 30MPG. The more I worked on that car the more hidden damage I found, so I sold it. Point for the examples, the engines that come in that Monte can be made a lot more efficient.

[apgrok1]

Hi, guys. I joined to answer my own question and back up my theory.
I don't have a Monte Carlo, I have a Chrysler Cirrus, but I have a set of triplets! Even though my wife has a mini-van, I am still thinking on trading to a bigger car to fit all three across in the back seat. I know I could step up to a Intrepid or a Bonnevile or some other latemodel fwd with an automatic, but I want to think I can do better than that.

[apgrok1]

Diesel engines are governed by fuel only. Everyone knows that. What that also means is that there very little intake vacuum. The engine does not have as much pumping loss as a gasoline engine, and that adds to the efficiency of the engine. Turbochargers are better yet, as they add pressure to the intake, although with most auto turbos, not until the engine is under accelleration. The turbo is dormant under cruise conditions.
So if a gasoline engine ran under cruise conditions with the throttle open more than halfway, you would have less pumping losses, and increased efficiency. However, that means the engine has to be small enough to be in that category.
Or, instead, install an undersized turbo for there to be a small amount of boost at cruise. Actually, that might be better and easier.
Does anyone know if you could get a 5-speed in a 2.3L turbo Thunderbird?

[apgrok1]

Diesel engines are governed by fuel only. Everyone knows that. What that also means is that there very little intake vacuum. The engine does not have as much pumping loss as a gasoline engine, and that adds to the efficiency of the engine. Turbochargers are better yet, as they add pressure to the intake, although with most auto turbos, not until the engine is under accelleration. The turbo is dormant under cruise conditions.
So if a gasoline engine ran under cruise conditions with the throttle open more than halfway, you would have less pumping losses, and increased efficiency. However, that means the engine has to be small enough to be in that category.
Or, instead, install an undersized turbo for there to be a small amount of boost at cruise. Actually, that might be better and easier.
Does anyone know if you could get a 5-speed in a 2.3L turbo Thunderbird?

[atomicradish]

Completely stupid idea.

Maybe you could put a metro motor into a Hummer too.

[unstable bob]

Originally Posted by apgrok1

Does anyone know if you could get a 5-speed in a 2.3L turbo Thunderbird?

Yes, a 5 speed was available behind the 2.3 turbo in the T-Bird. I dated a girl who had one. Pretty fun car.

[jharbert]

I wouldn't bother with a normally aspirated engine that small in a vehicle that heavy. With any vehicle, a certain amount of acceleration is necessary simply for safety reasons. A normally aspirated two liter engine in a Monte Carlo would be potentially unsafe, imo. Add a turbo or supercharger to bring the power up to acceptable levels, and you'd still have the small-engine benefits when simply maintaining speed, or doing anything else besides accelerating.

[CoyoteX]

Well in that case how about finding an older large car that came with a small engine. Something like a Ford Fairmont comes to mind. I know a guy that had one and it was a big car that was surprisingly light weight and had a 4 cyl stock. It got pretty good mileage just driving it normal and overall wasn't a bad car. Swapping to a 4spd auto or 5spd manual in a car like that could get you real good mileage for it's size.

I think putting a 4 cyl in a monte though is only going to gain about 5mpg over a V8. It is possible it could get a lot better but you would have to modify your driving style to take advantage of the smaller engine and that may or may not be possible depending on how and where you drive.

4 people in my metro and its mileage goes down pretty good and it absolutely doesn't like going up a hill.