are NA engines fun?
Discussion
Nanook said:
The shove in the back is the torque, but the acceleration you're seeing on the dials is due to the power?
I didn't really say that, but yes - in simple terms terms torque is pushing/pulling power and bhp is energy output: Turboed cars generally have more torque, so more of a low-down shove.popeyewhite said:
I didn't really say that, but yes - in simple terms terms torque is pushing/pulling power and bhp is energy output: Turboed cars generally have more torque, so more of a low-down shove.
In this case torque is twisting force whilst power is the rate of doing torque. How much "low down shove" you get depends on so many variables including the size of the turbo relative to the CC of the engine and the stroke. Acceleration also depends on the weight of what you are trying to move. wormus said:
In this case torque is twisting force whilst power is the rate of doing torque. How much "low down shove" you get depends on so many variables including the size of the turbo relative to the CC of the engine and the stroke. Acceleration also depends on the weight of what you are trying to move.
Yes, I know. That's why I said:popeyewhite said:
in simple terms
Shame that so many use bhp as sole metric of 'fun' . Enough's as good as a feast . more's better sort of thing . Big power can be fun of course , but low weight is much more so. And the most characterful and , yes, fun, n/a engines I've driven were a flat four 80bhp 1.3 and a 16v straight four 1.4 with 128bhp .
coppice said:
Shame that so many use bhp as sole metric of 'fun' . Enough's as good as a feast . more's better sort of thing . Big power can be fun of course , but low weight is much more so. And the most characterful and , yes, fun, n/a engines I've driven were a flat four 80bhp 1.3 and a 16v straight four 1.4 with 128bhp .
agreed. There's another thread about RWD and aquaplaning - guy wants an XFR. I drove an XJR with 550 horses, and while it was out loud laughably powerful it wasn't fun after a day pulsing the accelerator to revel in the power.
Bit of an odd thing to try and generalise. Both forced induction and NA cars can be setup with drastically different characteristics. I don't think you can really chose a "better'" approach but you can chose good and bad engines and specific examples of each which are gems.
Favourite engine I've owned in a car was the NA 3.6 in a 996 911. It wasn't very powerful but had a lovely torque curve. Current supercharged Evora is faster / more effective but there was a character about the 911 engine that the Lotus will never have.
Favourite bike engine was the Suzuki 1000cc V twin in the early TL1000S, nothing like the outright performance of my current straight 4, but lovely characteristics.
Favourite engine I've owned in a car was the NA 3.6 in a 996 911. It wasn't very powerful but had a lovely torque curve. Current supercharged Evora is faster / more effective but there was a character about the 911 engine that the Lotus will never have.
Favourite bike engine was the Suzuki 1000cc V twin in the early TL1000S, nothing like the outright performance of my current straight 4, but lovely characteristics.
KarlMac said:
ambuletz said:
not fun at all, that's why porsche are finally doing turbo'd ones.
They've only just started doing turbo ones? You sure about that? 
Small NA engines take more work to get the best out of them than small turbo engines.
IMO the results are worth it.
My 165 hp/950kg car will cruise quietly in 6th at 70 mph, but acceleration at that speed in 6th is glacial.
Drop to 5th, it's ok.
Drop to 4th, it's brisk.
Drop to third, the engine comes on song and the throttles start audibly gobbling air as it races toward the redline
.
If you are used to a turboed auto, it's probably all too much like hard work.
As for throttle response, at low revs (<3000 rpm) if you floor the throttle it will bog down - no fly by wire here. But keep the revs up and the throttle is sharper and more linear than any turbo car I've driven - the power is precisely metered by the pedal, and going from trailing throttle to full power is instantaneous.
What it can't do is win traffic light grands prix (without massive clutch slip and looking like a plonker) or in-gear roll-ons.
IMO the results are worth it.
My 165 hp/950kg car will cruise quietly in 6th at 70 mph, but acceleration at that speed in 6th is glacial.
Drop to 5th, it's ok.
Drop to 4th, it's brisk.
Drop to third, the engine comes on song and the throttles start audibly gobbling air as it races toward the redline
.If you are used to a turboed auto, it's probably all too much like hard work.
As for throttle response, at low revs (<3000 rpm) if you floor the throttle it will bog down - no fly by wire here. But keep the revs up and the throttle is sharper and more linear than any turbo car I've driven - the power is precisely metered by the pedal, and going from trailing throttle to full power is instantaneous.
What it can't do is win traffic light grands prix (without massive clutch slip and looking like a plonker) or in-gear roll-ons.
Currently we have the following in the fleet:
1.6 litre 4 pot turbo.
3.0 litre straight 6 twin turbo.
3.5 litre V8 NA tuned for high end power.
4.6 litre V8 NA tuned for low down torque.
5.0 litre V8 NA tuned more towards power than low down torque.
'Shoviest' engine is 3.0 litre twin turbo. Very easy to drive and negligible turbo lag.
Most fun engine is the 3.5 litre NA. It pulls surprisingly well at low to medium revs but really comes alive at 5k rpm and revs cleanly through to 8.5k rpm. This is accompanied by a sound track that is truly spine tingling. Whilst the other cars are all enjoyable in their own way, this is the only one that makes the hairs literally stand up on the back of the neck and produce audible lol sounds from the driver.
1.6 litre 4 pot turbo.
3.0 litre straight 6 twin turbo.
3.5 litre V8 NA tuned for high end power.
4.6 litre V8 NA tuned for low down torque.
5.0 litre V8 NA tuned more towards power than low down torque.
'Shoviest' engine is 3.0 litre twin turbo. Very easy to drive and negligible turbo lag.
Most fun engine is the 3.5 litre NA. It pulls surprisingly well at low to medium revs but really comes alive at 5k rpm and revs cleanly through to 8.5k rpm. This is accompanied by a sound track that is truly spine tingling. Whilst the other cars are all enjoyable in their own way, this is the only one that makes the hairs literally stand up on the back of the neck and produce audible lol sounds from the driver.
hman said:
I would take a large capacity v8 over a turbo in line 4 all day every day.
The difference is the noise and the instant power from the large capacity v8.
There's no replacement for displacement.
Yes there is, its called forced induction. If it was all about displacement, surely you would have said "I'd take a large capacity V8 over a small capacity turbo'd V8." - Comparing an I4 to a V8 is stupid, they're completely different things. What you're saying instead is I'll take a big V8 over an inline 4 with a turbo that is far too big for it, but allows it to make similar BHP figures as the big V8. I agree, so would I, as would most of the people on this forum I expect.The difference is the noise and the instant power from the large capacity v8.
There's no replacement for displacement.
Comparing two V8s, I'd take the smaller turbo unit. More lightness means better handling - far more important than bucket loads of power on the fun roads and majority of circuits in this country.
Matthen said:
Yes there is, its called forced induction. If it was all about displacement, surely you would have said "I'd take a large capacity V8 over a small capacity turbo'd V8." - Comparing an I4 to a V8 is stupid, they're completely different things. What you're saying instead is I'll take a big V8 over an inline 4 with a turbo that is far too big for it, but allows it to make similar BHP figures as the big V8. I agree, so would I, as would most of the people on this forum I expect.
Comparing two V8s, I'd take the smaller turbo unit. More lightness means better handling - far more important than bucket loads of power on the fun roads and majority of circuits in this country.
Agree the principle and I think it's even more nuanced than that. I'd probably take a VAG tfsi or whatever it's called now over a 1980s V8.... and I don't like the tfsi.Comparing two V8s, I'd take the smaller turbo unit. More lightness means better handling - far more important than bucket loads of power on the fun roads and majority of circuits in this country.
Are there many light cars with V8 turbos ? And I guess you'd extrapolate the lightness point and be back in a bike engined car or something. All about the specific engine and specific car.
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