Why displacement?

[Willy Nilly]

Just had a squizz at the underpowered car thread, and people keep eluding to the displacement of the engine.

Why do we buy a car based on the displacement of the engine, not the horsepower of said engine?

[Fox-]

Because otherwise you could decide you want a nice 200bhp car and end up with a wky VTEC instead of a nice V6.

[FreeLitres]

Low displacement, high power engines usually need thrashing to get the best out of them.

Also, they often have a "step change" where all the power arrives after a certain engine speed. i.e. Turbo spool up or VETEC yo.

HTH

Edited by FreeLitres on Friday 4th June 19:23

[kambites]

I'm quite happy with my little 1.8.

[pwd95]

Drive an S2000 & a Griffith 500 back to back & I defy you to say you prefer the performance of the ricer.

[Deranged Granny]

Because it's more ummmmmarhhhhyuhmmmmm than HP

[Gun]

There's no replacement for displacement.

[Vivafergaldo]

kambites said:

I'm quite happy with my little 1.8.

Me too. I'm only pushing 750kgs....

[Alex97]

Fox- said:

Because otherwise you could decide you want a nice 200bhp car and end up with a wky VTEC instead of a nice V6.

Your BMW must be verging on what, 200k now?

[Ozzie Osmond]

Displacement = flexibility

A 4-pot is quite sufficient in a light car. Can move along nicely!

BMW used to make a 4-pot 1.8 litre 5-series.....

[Glyn84]

I've been in a few turbo nutter barges and they are heaps of fun. On the track or a B road blast. For day to day driving and getting up to speed with minimal effort you can't beat a big V8. There's no substitute for cubic capacity, but you'll only realise having driven one.

[ZOLLAR]

Gun said:

There's no replacement for displacement.

I was waiting for that!. Its a true statement

[Vivafergaldo]

Glyn84 said:

For day to day driving and getting up to speed with minimal effort you can't beat a big V8.

I have, and disagree. OK if you want supertanker handling, but I get up to speed with minimal effort with my N/A 1.8 and I go 'round corners too!

[baughany]

I know this is out of tune with our times and all that, but I do think the fans of big engines are right.

My car's a 4 litreish but still feels a bit weak at low revs, how does that happen?!

Big loud sounds like it's going to stall at idle it's so lumpy US V8 is what I'd really like.

[Willy Nilly]

Gun said:

There's no replacement for displacement.

I didn't want to turn this into a bigger is better thread, what I wanted to know, is why people say "I have a 1.8 litre" not, "I have a 135hp car".

As for there being no replacement for displacement, I beg to differ. There is no substitoot for good design. I don't have the wide ranging car experience that many on here have, or pretend to have. But having spent a year or 2 in The States, I can confirm that some big engines are pants. The first time I clapped eyes on my 2.8 litre V6 company pickup. I thought, "oh, here we go, wheel spins and powerslides are on the cards". What I found out was that a Skoda Favorit was considerable quicker in every measurable area of performance while using half the fuel. And that a 5 litre Pontiac would struggle to keep up with base Fiesta.

While it might have looked good with a 2.8 litre or 5.0 litre badge on the back, the fact remained that neither of the engines had over 110 horses, and they were rather lazy horses. So why do we advertise/concern our selves with the CC of the car, not the HP?

[300bhp/ton]

Willy Nilly said:

Just had a squizz at the underpowered car thread, and people keep eluding to the displacement of the engine.

Why do we buy a car based on the displacement of the engine, not the horsepower of said engine?

as a rule bigger displacement (or effective displacement with forced induction) means more torque and power.

[ZeeTacoe]

Vivafergaldo said:

Glyn84 said:

For day to day driving and getting up to speed with minimal effort you can't beat a big V8.

I have, and disagree. OK if you want supertanker handling, but I get up to speed with minimal effort with my N/A 1.8 and I go 'round corners too!

But the headgasket won't go on the way to 70.


God I love these bks generalisation threads.

[Willy Nilly]

300bhp/ton said:

Willy Nilly said:

Just had a squizz at the underpowered car thread, and people keep eluding to the displacement of the engine.

Why do we buy a car based on the displacement of the engine, not the horsepower of said engine?

as a rule bigger displacement (or effective displacement with forced induction) means more torque and power.

A leading manufacture of agricultural machines that builds tractors had a version which we will call a 7820. In the US, where cubes are king, it came with an 8.1 litre. The version that came to Europe had a 6.8 litre engine. The 6.8 had marginally more power, slightly more torque at slightly lower revs and marginally better specific fuel consumption. Not a car I know, but I prefer a good engine, to a big one.

Do people look at the cars HP or just say they want an engine with a particular cc?

[300bhp/ton]

Glyn84 said:

I've been in a few turbo nutter barges and they are heaps of fun. On the track or a B road blast. For day to day driving and getting up to speed with minimal effort you can't beat a big V8. There's no substitute for cubic capacity, but you'll only realise having driven one.

Fully agree, I can make pretty good progress and if off the public roads get to 80mph all by keeping it under 2000rpm and with only 4 gears. Also makes very easy work if you live in hilly/mountain areas like Wales or the Lakes. It almost never needs to down shift and use revs, just plods along on a wave of torque

[300bhp/ton]

Vivafergaldo said:

Glyn84 said:

For day to day driving and getting up to speed with minimal effort you can't beat a big V8.

I have, and disagree. OK if you want supertanker handling, but I get up to speed with minimal effort with my N/A 1.8 and I go 'round corners too!

and