why id pick the larger engine over the smaller one with +bhp
why id pick the larger engine over the smaller one with +bhp
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i remember

Original Poster:

3,296 posts

216 months

Friday 7th May 2010
quotequote all
A thought occurred to me recently, that lots of manufacturers now are getting the same or even more output than the previous generation model car. This is obviously because of the tighter and tigher laws governed by Co2 emissions, so manufacturers now have to make do with smaller engines but dont want to make them slower.

If your a bit lost with what im on about this could shed some light

Take the golf R32, when the MK4 came along to me this one was a bit special, 3.2 V6 with 237bhp
MK5 same engine 246BHP.
The MK6 with a 2L 4 Pot, 266BHP.
2L 4pot, just doesnt sound as good as 3.2L v6 in my head

On the front page today is this Ferrari link
http://www.pistonheads.com/news/default.asp?storyI...

It states that Ferrari will most likely be going for forced induction on their models now using V8's, most likely with more power. So that will be the end of v12 powered Ferraris

Mercedes are going to drop there V12's and that 6.2V8 for 5.5L supercharged V8's in future with more power.

So basically what im saying is, even though companies will be making quicker cars with smaller engines, why do i still feel that the smaller engines with more power just dont win me over rather than bigger sized engines with less power.

So yes i said it, id have a bigger engine with less power over a more economical more power smaller engine, and i know some of you are thinking the same thing.


TheEnd

15,370 posts

218 months

Friday 7th May 2010
quotequote all
the larger engines usually have more torque, and just go when you put your foot down whenever, but forced induction (at least from turbochargers anyway) is more efficient, so you can make smaller, lighter, more economical engines with the same headline BHP as somthing double the capacity but with a lot more moving mass.

TonyRPH

13,546 posts

198 months

Friday 7th May 2010
quotequote all
I agree with the OP.

I once owned a Mazda MX3 - this had a 1.8 V6 and it was the sweetest sounding motor.

I would definately have a 1.8 - 2L V8 for sure!!!

But sadly, as the OP points out, manufacturers seem to be going for forced induction engines with fewer cylinders.



Edited by TonyRPH on Friday 7th May 19:03

TonyRPH

13,546 posts

198 months

Friday 7th May 2010
quotequote all
TheEnd said:
the larger engines usually have more torque, and just go when you put your foot down whenever, but forced induction (at least from turbochargers anyway) is more efficient, so you can make smaller, lighter, more economical engines with the same headline BHP as somthing double the capacity but with a lot more moving mass.
Surely you mean "..but with a lot *less* moving mass"?

seismic22

662 posts

199 months

Friday 7th May 2010
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What about reliability, is there an argument for the bigger capacity engine being less stressed and so over thousands of miles, whether the little engines got more bhp or not, the bigger engine will be more reliable because its not squeezing every one of the last possible horse's out of it?

LuS1fer

43,544 posts

275 months

Friday 7th May 2010
quotequote all
Sadly, these smaller engined high power cars are only theoretically more economical or potentially more economical. As has been demonstrated for many years by Yank muscle cars, they can achieve exactly the same or better mpg speed for speed. What I mean by that is when thrashed, these engines are usually less economical. In a US track test between a Porsche 911, a 350Z and a C5 Z06, the Corvette was easily the most economical.

bimsb6

8,799 posts

251 months

Friday 7th May 2010
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hairykrishna

14,528 posts

233 months

Friday 7th May 2010
quotequote all
LuS1fer said:
Sadly, these smaller engined high power cars are only theoretically more economical or potentially more economical. As has been demonstrated for many years by Yank muscle cars, they can achieve exactly the same or better mpg speed for speed. What I mean by that is when thrashed, these engines are usually less economical. In a US track test between a Porsche 911, a 350Z and a C5 Z06, the Corvette was easily the most economical.
When pushing on, yes. If you're using it for a daily driver a smaller turbo engine tend to be far more efficient, at least in my experience.

TheEnd

15,370 posts

218 months

Friday 7th May 2010
quotequote all
TonyRPH said:
TheEnd said:
the larger engines usually have more torque, and just go when you put your foot down whenever, but forced induction (at least from turbochargers anyway) is more efficient, so you can make smaller, lighter, more economical engines with the same headline BHP as somthing double the capacity but with a lot more moving mass.
Surely you mean "..but with a lot *less* moving mass"?
i was comparing it to a bigger NA engine, eg 2.0 turbo vs 4.0 normally aspirated (with the 4.0 having more moving mass

TonyRPH

13,546 posts

198 months

Friday 7th May 2010
quotequote all
TheEnd said:
TonyRPH said:
TheEnd said:
the larger engines usually have more torque, and just go when you put your foot down whenever, but forced induction (at least from turbochargers anyway) is more efficient, so you can make smaller, lighter, more economical engines with the same headline BHP as somthing double the capacity but with a lot more moving mass.
Surely you mean "..but with a lot *less* moving mass"?
i was comparing it to a bigger NA engine, eg 2.0 turbo vs 4.0 normally aspirated (with the 4.0 having more moving mass
Sorry - misread your paragraph.

My bad.

RobM77

35,349 posts

264 months

Friday 7th May 2010
quotequote all
yes Generally, the smaller engine will lose drivebility, either via having less torque (but getting power through more revs), or by having a turbo, which will give lag.

balls-out

3,794 posts

261 months

Friday 7th May 2010
quotequote all
I bought a car with 5.7 small block Chevy V8. Nothing else feels the same anymore. There is no substitute for cubes.

Flying machine

1,265 posts

206 months

Saturday 8th May 2010
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hairykrishna said:
LuS1fer said:
Sadly, these smaller engined high power cars are only theoretically more economical or potentially more economical. As has been demonstrated for many years by Yank muscle cars, they can achieve exactly the same or better mpg speed for speed. What I mean by that is when thrashed, these engines are usually less economical. In a US track test between a Porsche 911, a 350Z and a C5 Z06, the Corvette was easily the most economical.
When pushing on, yes. If you're using it for a daily driver a smaller turbo engine tend to be far more efficient, at least in my experience.
Not sure I'd agree with that in all circumstances - when I bought my 911 I was quite suprised that it has been slightly better on fuel than my previous scooby or MR2 turbo's. Plus it sounds cloud9

hunt_the_fox

1,044 posts

255 months

Saturday 8th May 2010
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A smaller turbocharged engine will deliver pretty good mpg if you stay off boost. I recorded 35mpg in my 996 turbo on a journey the other day which is good compared to the 6mpg it returns on trackdays!!

HertsBiker

6,443 posts

301 months

Saturday 8th May 2010
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3 cylinder is the way to go - perfect balance, thrashes well, responds to turbocharging almost like a bike engine. If someone did a 1500cc twin-turbo'd triple it would be mental.

RobM77

35,349 posts

264 months

Saturday 8th May 2010
quotequote all
HertsBiker said:
3 cylinder is the way to go - perfect balance, thrashes well, responds to turbocharging almost like a bike engine. If someone did a 1500cc twin-turbo'd triple it would be mental.
I was going to say something similar myself. Smaller engines do drive better - they have lower rotational mass and generally respond better, but of course they only work when pulling a small mass smile

Willy Nilly

12,511 posts

197 months

Saturday 8th May 2010
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balls-out said:
There is no substitute for cubes.
There is quite a good substitute for cubes, good engine design.

I have driven a 2.8 V6 that would struggle to out perform most 1.0 litre cars and have experienced a 5.0 with similar lack of any measurable performance.