what makes a good engine.

well, seeing as the other engine thread got locked,
i thought it might be good to throw up not a poll
but a simple debate.

what makes a good engine?

is it purely about numbers?
does greatest BHP= greatest engine
or does torque play a bigger part?
how about engine weight?
engine cost?
technology involved?

is a N/A engine 'better' than a turbo because it is technically superior/more efficient/insert your choice here.
is the S2000's inline 4 a good engine cos it can rev to 9000rpm or is its low torque a failing?
does the fact that honda engineers discovered new types of vibrations/stresses at anything over 8000 rpm something to go 'ooooh' at or 'so what?' ?
does using the latest hi precision enginnering/materials make a good engine if it costs more?

let's say you can get 150 bhp from a 1.5 litre engine.
is that better/worse/the same as a 200 bhp from a 2.0 litre?
how about a 1.5 litre 150bhp engine compared to a 2.0 litre 180bhp engine?

i guess in an ideal world, the best engine would be the one with the highest bhp and torque with the lowest possible capacity and weighing the least.
the point is, this doesn't exist.

so what do you think is a good engine and more importantly, why?

Good engine qualities

Inexpensive
Good balance of hp/tq
good gas mileage
lightweight
durable

I guess my candidate for best engine ever would be the VW aircooled. I know its pretty "low" as far as engines go, but I dont see any other engine that can take the beating that these things go through, not to mention working on one is like putting together a lego set. I have one thats almost half a century old and it still runs fine. From an engineering standpoint I find that impressive.

Good gas mileage & durable and something that is easy workable with.

Just something thats not to complex and is easly tuned. Not some huge high configured engine were the slightest tinker will set it off something simple.

weight/output - you whant the most powerful engine with the least polar momentum (this is the reason for designing high specific output engines)

its center of gravity should be as close to the ground - this is the big advantage of boxter engines, and here is also one of the advantages of a pushrod over DOHC(except for boxter DOHC of couse)

it should be themodynamically efficient - most output for least gas. Reason for high compression and trick AF maps

it should have a very large and usable powerband with a stable TQ along its RPM

it should be of course reliable


Probably the best design overall would be a twin turbo boxter as in the TT 911. Turbos will offer the largest and most flexible powerband along with a high specific output and higher thermodynamic efficiency. And the boxter layout will ensure a low center of gravity.


PS. Lets not hear please about such ridiculous lines as turbos are good only for top end or the mystical turbo lag taht is suposed to makes all turbo engines unresponsive. If you still think those statements are correct do a search in the Forced Induction forum.

...."mystical turbo lag "

they can't help it.
most people still remember the articles about the 2002 turbo.....
they forget about such things as sequential turbos and variable vanes and all that.
oh and about 20 years of technological improvement.

i hear what you're saying with the twin turbo (porsche) boxer engine.
well, the thing there is that if you take away the turbos,
you still have a crackingly good engine.
(engine=double chocolate cake
engine+turbo=double chocolate cake+custard)

talking about boxers, i've always had a thing for the boxer 12 in the 365 boxer, back when it was still chain driven.
the car dealer next to my old restaurant had one when i was wee nipper and i think it was the first car noise that 'shocked' me.
hooked ever since.
i remember during the top trump days when all the kids were raving about testarossa and lamborghini countach 5000s with the huuuge wing i was hunting for posters of the 365 boxer that never existed....
bah!

anyway.
how about a little list of what you think are good engines?
for every sector.
best engine for technology maybe?
best engine for the masses?

Best tech engine I would say is the BMW line of I6's...theres an insane amount of weight saving technology, and a lesser known variable timing system

For the masses its Nissans 3.5L V6....its in all of their midsize cars including G35 and the Z... it varies hp from 265 to 300 now, it was one of the 10best engines last year, its powerful, relatively fuel effecient, and in very reliable

Well, honestly I think GM makes the world's best engines even though they've stuck with "archaic" technology for so long.

In fact, I think it's because they've used that archaic tech for so long that they make such good engines. Take, for instance, the 3800 series of V6's. No, they're not the technological equal of the Nissan VQ series or the Honda Accord 3.0. However, they deliver excellent fuel mileage (even in supercharged form), excellent usable power (especially in supercharged form) and will willingly give up 200K in miles of daily grind service without batting an eyelash.

Beyond that, they're very inexpensive to maintain (c'mon, a coil pack is $20 and is a ten minute job to replace) and parts are plentiful thanks to the engine's near universal application. I do honestly feel there are very few engines better than GM's 3800.

Agreed. I've always liked GM's pushrod V6 as a daily driver, and it responds very nicely to supercharging.

i love my 350.....cheap parts, reliable, easy to work on........the only down is the gas mileage, but its a truck.

Well, honestly I think GM makes the world's best engines even though they've stuck with "archaic" technology for so long.

In fact, I think it's because they've used that archaic tech for so long that they make such good engines. Take, for instance, the 3800 series of V6's. No, they're not the technological equal of the Nissan VQ series or the Honda Accord 3.0. However, they deliver excellent fuel mileage (even in supercharged form). I do honestly feel there are very few engines better than GM's 3800.

I agree. How many models does gm make with cylinder De-Activation? I also heard ford is or has made some as well.

What about Mazda's rotary engine? They claim that since it only has two moving parts, it lasts longer? Anybody who drives one of these, how do you feel about them? How does it do for a daily driver, since it has such a high redline

Not sure about the RX8, but I know a guy with an RX7 that complains about how he has to replace something (rotary seals I believe) every 30k miles or so...

Not sure about the RX8, but I know a guy with an RX7 that complains about how he has to replace something (rotary seals I believe) every 30k miles or so...

That would be right! Rx-7 have always had that problem with seals aka for V configured engines its the head gasket.

yeah but the head gaskets on an engine block tend to last a hell of alot longer than the seals on the rotary. only downpart about a rotary in my opinion.

BTW: i agree with everyone else. a motor has to be efficient making it last longer, good gas mileage, above par tuning capabilities and performance. i think some of the best engine in my eyes without money being a factor would be the bmw's. my vote goes to the ag 3.2L I6 in the m3. but thats of course without money being a small factor.

GM's engines rule, the new LS2 in the Vette and soon to be in the GTO's has 400 horse, it's 364 cubic inches yet still is rated at getting 28 mpg on the highway, thats impressive if i may say so. plus they make some of the best crate engines there are... :boink: ZZ 383/425 :boink:

how can you even consider the new LS2 if it hasnt even stood its ground yet? i mean c'mon. by the time they drop it in the new vette, it might only last 30k miles before it needs a rebuild. we hardly know anything about this motor. chances of it being a crappy motor, very slim. im just saying though, you cant compare something that hasnt even debuted yet.