Small vs. Big: Some Pros . . . and Cons

by Eric Peters
EricPetersAutos.com

If you’re trying to decide whether to buy a bigger – or smaller – car, you might want to consider some of the following pros and cons:

Small cars usually perform better with manual transmissions

This is because they usually have smaller – and lower torque at higher RPM – engines. This means you have to get the engine revving to get the car moving. Or at least, moving quickly. With a manual, this is easy. You raise the RPMs, let out the clutch – and off you go. With an automatic, not so much. It takes a moment for the engine to build up speed (RPMs) after you push down on the gas pedal with the transmission in Drive – a moment or two for the engine to get into the higher range of its powerband, where it makes its power – and torque. In the meanwhile, other cars are passing you by.

Most small (four cylinder) engines have torque peaks well above 4,000 RPM – and don’t make much torque at all in the idle to 2,000 or so RPM range – the engine speed you’re starting out at from a red light.

As an example, the ’12 Kia Soul I recently reviewed (see here for that) had a 1.6 liter engine with a torque peak at 4,850 RPM. It also made very little torque – at any engine speed. Maximum torque from this engine is just 123 ft.-lbs. – not a lot to get 2,615 lbs. of vehicle moving.

The result of a small engine with not much torque at all – and whatever torque there is way up there in the powerband – teamed up with an automatic transmission – is usually sluggish performance. Especially when accelerating from a standstill.

Bigger cars, in contrast, usually have bigger engines – sixes and sometimes eights. These engines produce more torque – and at lower engine RPM. For example: The full-size Chrysler 300?s big V-8 produces tremendous torque – 394 ft.-lbs. – at 4,200 RPM. Much of this prodigious torque is also available at lower speeds – making it ideal for pairing with an automatic transmission. A big car with a stick can be plenty of fun to drive – but you usually won’t lose much in the way of performance by going with the automatic, if you prefer to let the transmission do your shifting for you.

Diesel engines – which make lots of torque down low in the powerband – also work well with automatics. Unfortunately, there are only a handful of small cars available with diesel engines in the U.S.

Smaller cars are usually less crashworthy

This one’s obvious – or ought to be. But the way crashworthiness ratings are published can be very misleading – because they don’t rank cars in absolute terms but only against other cars within their class of car. In other words, a compact is compared to other compacts – and a full-size car compared to other full-size cars. Compact cars are not compared with full-size cars. So, a compact with a 5 Star rating may be superior to another compact with a 4 star rating. But it’s still probably inferior to a full-size car with a 4 star rating. As a rule, the larger (and heavier) the vehicle, the more crashworthy the vehicle.

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August 7, 2012

Copyright © 2012 Eric Peters

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