Naturally Aspirated vs. Forced Induction: which is best

[YOUTUBE]http://www.youtube.com/watch?v=bfVNIZ0RKik[/YOUTUBE]

This is another excuse thread for posting cool car videos. I don't mind :)
 
^plenty of biker comments there :lol: they really hate losing, don't they..
 
I was only talking about factory turbo engines. most na setups with turbos strapped on arent gonna be as solid as a stock turbo. most engines can handle 5 psi though. They just cant do it for long

Have you ever looked at the book Maximum Boost? they have a a whole section on running a stock motor with an aftermarket turbo charging system. Running a reasonable amount of psi (7ish) only adds an extra strain of about 20% on the engine, and that's only when using full boost which for most people isn't for more then a minute everyday unless at something like a track.
 
Still isn't as good as a factory set up where the engine bits have been beefed up for the snail(s).
 
This is another excuse thread for posting cool car videos. I don't mind :)

I found it hard to believe that he was racing a R1.. I'd say it was a R6..

Here is a more objective vid.:p
[YOUTUBE]http://www.youtube.com/watch?v=aHtVdhzyrGY[/YOUTUBE]

And another:
[YOUTUBE]http://www.youtube.com/watch?v=Dc8thQpJ38A[/YOUTUBE]
 
The hayabusa is obviously faster than an R1, and the Cosworth is faster than a ZR-1 Corvette..
 
The hayabusa is obviously faster than an R1, and the Cosworth is faster than a ZR-1 Corvette..

Actually in pure acceleration the R1 is faster..
Almost the same power and a lot lighter..

edit. but 0-150mph? in 13.2 sec is pretty damn fast!
 
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Have you ever looked at the book Maximum Boost? they have a a whole section on running a stock motor with an aftermarket turbo charging system. Running a reasonable amount of psi (7ish) only adds an extra strain of about 20% on the engine, and that's only when using full boost which for most people isn't for more then a minute everyday unless at something like a track.

Well you didn't exactly disagree with me. I have read that book, its' pretty good but some things are a bit stupid. Especially his recommending turbos over belt driven blowers on account of "crank flex and bearing damage due to the belt..." :lol:

Cooling issues seem to be the problem with n/a engines with blowers strapped on. Street usage usually isn't a problem, and short throttle squirts, but prolonged boost and you run into coolant/oil temp issues. It's the Achilles heel of boost miata's, and many an A70 Supra (87-92).
 
See, now I am wanting that supercharger for my VFR. 170 BHP, baby!
 
Actually in pure acceleration the R1 is faster..
Almost the same power and a lot lighter..

edit. but 0-150mph? in 13.2 sec is pretty damn fast!

Well, the ZR1 does 0-150 in 15.5 seconds, and that Sierra is probably a good 400 kg lighter than a ZR1.. (ZR1 curb weight 1550kg, stock Sierra Cosworth curb weight <1200kg and the one in the vid is most likely stripped out.) Also, the vid doesn't state whether the Sierra has 609hp at the crank or at the wheels..

I'd say it's very possible that the bike in the vid is an R1..:)
 
Assuming an equal level of sophistication in the engines, a normally aspirated engine is fundamentally more efficient at converting fuel into horsepower because the intake charge air is cooler. Any kind of forced induction, by definition, compresses the air and heats it up quite significantly. Even the use of intercoolers is only a stop-gap measure.

However...there's always a "but" -- you have to look at the actual use patterns for an engine. Outside of racetracks, most engines spend very little time developing maximum power. So turbos can be ideal, because while they might be less efficient than a normally aspirated engine at full throttle, off-boost, cruising down the highway at light throttle, they can often be more efficient. Think of a turbo car as a gasoline-gasoline hybrid if you will -- a small engine that has an extra "booster" for the times you need it, like merging into traffic, etc.

Steve
 
Assuming an equal level of sophistication in the engines, a normally aspirated engine is fundamentally more efficient at converting fuel into horsepower because the intake charge air is cooler. Any kind of forced induction, by definition, compresses the air and heats it up quite significantly. Even the use of intercoolers is only a stop-gap measure.

However...there's always a "but" -- you have to look at the actual use patterns for an engine. Outside of racetracks, most engines spend very little time developing maximum power. So turbos can be ideal, because while they might be less efficient than a normally aspirated engine at full throttle, off-boost, cruising down the highway at light throttle, they can often be more efficient. Think of a turbo car as a gasoline-gasoline hybrid if you will -- a small engine that has an extra "booster" for the times you need it, like merging into traffic, etc.

Steve


Best anomaly I've heard for a turbo. My Passat is generally happy to waft about, off the turbo, with excellent fuel economy. Slip the gearlever into "S" or push down hard on the throttle and it's ready for action. :mrgreen:
 
Well, the ZR1 does 0-150 in 15.5 seconds, and that Sierra is probably a good 400 kg lighter than a ZR1.. (ZR1 curb weight 1550kg, stock Sierra Cosworth curb weight <1200kg and the one in the vid is most likely stripped out.) Also, the vid doesn't state whether the Sierra has 609hp at the crank or at the wheels..

I'd say it's very possible that the bike in the vid is an R1..:)

There where no ZR1's in the vids i posted...

And any Superbike with a decent rider will do 0-150mph in less than 12 sec..
The lastest incarnation of the R1 is down to low 11s

So conclusion: Either the rider was crap/didn't try, or that wasn't a R1...
 
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Earn more money and get both.
 
For a daily driver I would pick n/a over turbo or s/c. I have enough problem with my Eagle Talon and I've seen the problem my uncle's 200SX (S12) had. Generally force induction cars just requires more care and maintenance. For a daily driver I rather sacrifice some power and fuel economy and go with a larger displacement n/a car.
 
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For a daily driver I would pick n/a over turbo or s/c. I have enough problem with my Eagle Talon and I've seen the problem my uncle's 200SX (S12) had. Generally force induction cars just requires more care and maintenance. For a daily driver I rather sacrifice some power and fuel economy and go with a larger displacement n/a car.

A DSM is not exactly a bastion of reliability.
 
no replacement for displacement.

plus on the track, NA cars have something the boosted guys don't: balance.


id only get a turbo diesel. not petrol hehe
 
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