Redux: Why American cars tend to have big engines.

This isn’t actually the first time I’ve made a blogpost like this. For those of you who don’t remember, I made one about two years ago on the exact same subject. Why am I doing it again then? Simple, I can explain more reasons now than I could then. Not only this but I can give better explanations for the same reasons too. If you want to read the original you can in the link down below. This also won’t be the first time I redo an old article either.

With the nostalgia trip done. Lets move on shall we?

1: Big Engine + Low Compression = Happy Reliability.

This is a point that has been stated over and over and over and over again. However, it’s worth restating because it’s still true and is relevant to the points I’m trying to make.

Typically with smaller engines, higher compression is needed to make more power. Even when you add on turbos and other forced induction goodies the car will still be running a higher stress level than an engine with the same power but bigger displacement. Smaller engines can’t take as much added stress compared to a bigger (less stressed) engine. Smaller engines simply require more work to make them less prone to breaking under high pressure (from HP and PSI due to turbocharging). A small engine will need higher compression (and potentially turbocharging) to make 300 HP. Whereas a bigger motor under less stress can just be “built” to 300 HP (a mass generalization but I think you get the point). Leaving tons of potential left in the bigger motor. Whilst the smaller engine won’t be making much more HP without changing from stock internals.

It’s why LS motors can go on forever without needing a complete rebuild (or at the very least, they can survive longer before needing a major rebuild compared to other engines). It’s also why they can be tuned to oblivion on stock internals. Even the Viper’s V10 is extremely resistant to breaking even after you add aftermarket goodies onto it. Calvo Motorsports (an aftermarket tuning company) were testing the Gen V engine to see how much HP it could take before it broke. They got up to 1450+ whp before the engine couldn’t take it anymore. And that was with stock internals. These engines are ridiculously strong due to the low-stress nature of the engine. (Source: https://driveviper.com/forums/threads/17553-Just-picked-up-my-TT-Calvo-Motorsports-Viper Scroll down to the user “slowhatch”).

Bigger engines are easier to modify without needing extra mods (on top of the others) to keep them from blowing up in your face.

2: Dayliability/Torque.

No not that kind of daily. But how easy it is to drive a car every day. Stuff like pulling out to overtake someone or how low the revs are on the highway. That kind of Dayliability.

Bigger engines can have more torque than smaller engines. Better still, they tend to have it much lower down than smaller, turbocharged engines. Meaning you don’t have to change down as many gears just to pass someone on the highway. Or in some cases, you don’t have to go right the way up to the redline just to pass someone.

Now this next bit does delve a little bit into the whole Downsizing Fiasco we’ve been seeing in the industry for a little while now. But in short, a bigger engine in a big car will sit at a lower RPM than a smaller engine in the big car. Why? Because the engine doesn’t have to work as hard to maintain a certain speed. Imagine a 3.0 liter V6 in a something the size of a Durango. Now imagine it’s turning 1,500 RPMs when cruising. Now put a 2.0 liter turbocharged 4 cylinder in the same car and it’ll turn something close to 3,000 RPM. This is bad because the higher the RPMs go, the less fuel efficient the car as a whole will be. This is why downsizing doesn’t work for everything (and something many people should have realized a lot sooner).

3: Cost.

What I mean is the cost to make an engine. Let me draw you a picture. Lets take a 5.7 liter engine and give it 400 HP. Now take a 2.4 liter engine and also give it 400 HP. Now put both engines in the same car (not at the same time) and the car with the 2.4 liter engine will be more expensive. Why? Because engineering costs. The amount of over-engineering it would take to make the 4 cylinder engine even handle 400 hp (much less being reliable at it) is far more than the cost of simply building the 5.7 liter engine to 400 hp in the first place (I use “building the engine to X hp” as a generalization). This also leaves room for the 5.7 liter engine to become more powerful (because there is still room left in the tune). Whereas the 2.4 is pretty much at the limit of power. Major changes would be needed to get much more out of (essentially getting rid of the stock internals).

This also cuts cost in the aftermarket department. The 5.7 will be able to handle more power before the switch from stock internals will be necessary (stuff like bolt on parts and other quick but effective mods). Whereas the 2.4 will need to change right from the get go. Only then will the addition of power be a possibility without blowing the engine to bits (for the most part).

Of course some people would say “just build the smaller engine with better parts.” But that would be completely missing the point. Better parts = More expensive parts and thus means the engine will be even more expensive on top of that (and that will affect how expensive the car utilizing the engine is).

This isn’t the only part where cost comes into play though. In America there isn’t a tax on engine size. Whereas other countries do have taxes. The bigger the engine, the bigger the cost (of the tax). So it simply doesn’t matter how big the engine is here (in America).

4: Weight.

Chart made by Flux 7.0! No better way to illustrate this than with a chart! Thanks man!

Big engines don’t always mean heavy engines. The Viper’s 8.4 liter V10 is all aluminum. And LS motors can (depending on generation) weigh less than competing engines. And because engines of this they tend to be N/A (all motor power ftw). The engines also are comparatively smaller than engines using forced induction. Not to mention that instant throttle response. Giving you that “pushed back in your seat” feeling that can be hard to match otherwise. N/A engines (especially pushrod engines or cam-in-block engines) are lower than engines with Dual-Overhead cams or superchargers and can be narrower than engines with turbos because it’s just motor in the enginebay. Rather than add on goodies in the engine bay taking up space (how much space you have left is completely car specific). So it’s no wonder that these engines can be lower and lighter than their forced induced counterparts.

And that’s it! Thank you for taking the time to read this article! If I’ve forgotten anything then do please tell me down below. Once again thank you all for reading and I’ll see you guys next time.