NASP or TURBOCHARGED POWER

[obi_waynne]

What is your take on the great NASP or TURBOCHARGED POWER debate?

I'm definately sold on turbos, that massive kick you get as the turbo cuts in is awesome plus off boost you have a relatively economical car.

 

[lutonmatt]

think it all goes on what you want a car for if its just a go to work in and good fuel has to be nasp or a td

but if a play toy then a turbo is a good way to go i want a superchager on my next toy

 

[HDi fun]

I've never noticed turbochargers kicking in as such. Unless we're considering MG Montego Turbos all the forced induction cars I've driven have been very linear in their power and torque delivery.

Obviously you can feel and hear the turbo but I've never experienced a sudden transition in performance.

 

[turbonutter69]

I've never noticed turbochargers kicking in as such.

You don't so much these day but my old Fiesta Rs did give quite a good kick when the boost kicked in. It used to pin me to the seat when the boost came on.
My first Impreza did the same but it was much much more progressive but you could still feel the kick when the turbo spooled up.

 

[obi_waynne]

My A3 Turbo is fairly linear in delivery, but in the A4 the power really wakes up at 2200rpm and is very noticeable.

 

[HDi fun]

My A3 Turbo is fairly linear in delivery, but in the A4 the power really wakes up at 2200rpm and is very noticeable.

I agree - the 1.8T does a very good job of disguising the fact that it's sub 2 litres. Even in the early TTs tuned to 225bhp (factory) you'd have a job to spot the breakpoint, so linear is the torque delivery for that engine.

If anything, my BMW can be a bit peaky, not switch on/switch off as such, but it doesn't really get going until 3500 - 4000rpm.

 

[herb]

My A3 Turbo is fairly linear in delivery, but in the A4 the power really wakes up at 2200rpm and is very noticeable.

ahh but waynne if you would have had your a3 mapped you would have noticed a difference

and on the debate side of things
me personally i would say a na engined car is more a drivers car! having to use your gears to drive it to its best. turbo cars make driving lazy!!!!

 

[Massive]

i think superchargers should be an option in this debate, or supercharger or turbos

well nasp is very fun to drive and like herb say you have to work at gear changes to keep it going down shifting going into corners so you can get some good power on the way out

however in a turbo you do get a good kick, i remember when my friend dad got a fait coupe my god that felt quick when the turbo kicked in

 

[SLEEPER]

I dont mean to be confrontational but......................

Obviously you can feel and hear the turbo but I've never experienced a sudden transition in performance.

Obviously not driven or even been a passenger in a a car running a high boost turbo set up going quickly

Its one of the universally accepted facts . Any tuned turbo engine doesnt produce real power untill the tubos spool up to there operating speed Then all hell breaks loose ( sometimes literally)
Thats why twin turbos are often sequetial eg standard twin turbo scooby - a small turbo provides the low down power then a larger one takes over. Unfortunately there is often a flat spot inbetween.usually

High power turbo cars will often have one large turbo or two smaller ones this coming on together. Difficult to set up right but can give sudden brual power which has to be felt to be truly understood

Power increases by 50% within 500rpm so I think that qualifies as sudden



Also herb -
ahh but waynne if you would have had your a3 mapped you would have noticed a difference:wink:

and on the debate side of things
me personally i would say a na engined car is more a drivers car! having to use your gears to drive it to its best. turbo cars make driving lazy!!!! Yesterday 10:12 PM
'and on the debate side of things
me personally i would say a na engined car is more a drivers car! having to use your gears to drive it to its best. turbo cars make driving lazy!!!! '

again IMHO that is completely wrong - on a high power turbo car often the power band is much smaller that an NA engine so you need the gears more not less as the powe difference at different rpm is huge .
The graph shows a large torque spread on a single turbo with standard cams etc this would be much smaller.

Re superchargers
There is no kick .
With a charger it is direct drive so power gain is linear and you just get more power alll the way through the rev range compared with the same engine in NA form.
With the same engine if the turbo was big enough to out perform the charger the required size would mean there would be little or no improvement untill it spools up . Then you would have more power than the charger


Please note I am not saying turbo cars are always better .

Oh and turbo deseils are completely different to turbo petriol in how they work.

 

[HDi fun]

When the 406 was remapped the difference between on and off boost was more noticeable simply because there was an extra 100lbft of torque to shove the thing around. But it still delivered pretty smoothly - not a sudden switch on type of feeling.

Diesels do lend themselves especially well to turbocharging due to the absence of a throttle.

I remember driving a highly modified 300ZX twin turbo in about 1991 and that was savage in it's on/off behaviour. This made it hard work to drive - constantly up and down the gearbox, I expect I'd have preferred it in standard tune for general road use.

 

[bigbadjoe]

Im turbo mad. Always have been. Ever since a kid, and my old man making me tell him what point the turbo kicked in on his Volvo! I had to listen in and tell him.

BUT - Is a turbo charged engine a true reflection on the BHP outcome of the vehicle? Or is it miss leading.

As the turbo mainly helps with acceleration, rather than top speed.

 

[HDi fun]

Definitely will affect top speed. Turbochargers increase torque output, which can only result in an increase in power output.

 

[bigbadjoe]

Definitely will affect top speed. Turbochargers increase torque output, which can only result in an increase in power output.

Yeah, but only forcing the engine to do so. The engine could not do it alone. Don't get me wrong, I am all for Turbo's. But the question asked is are they a true reflection on BHP? I have often wondered that.

 

[HDi fun]

If you take off the turbo then the torque and therefore power output will reduce drastically.

 

[bigbadjoe]

Correct! And what your left with is what bhp the engine can produce.


.....

I have kind of lost my way of thought of this chatt. I cant get out in words, what my head is thinking....... Never mind. What ever I put down, makes me sound like I'm going against turbo's, witch of corse, is not the case. Sod it. I'll stop talking

 

[obi_waynne]

A turbo makes an engine a lot more efficient, allowing it to burn more fuel so it is plusses all round in my book.

 

[T9 man]

Turbos's certainly get my vote
I have had 4 different turbos on the car in it's 8 year life to date. The last three have all been hybrids and each time I have upped the turbo size, the BHP power has gone up accordingly! I know full well that the turbo adds considerably to the overall power output of the car, but I can't help wondering sometimes, what the standard power would be without the turbo's assistance? One of life's little mysteries I guess

 

[Big Fat Fatty]

my guess is not much the turbo is doing all the work and the engine is just there to feed it exhaust and keep up with it.

 

[Yugguy]

Turbos's certainly get my vote
I have had 4 different turbos on the car in it's 8 year life to date. The last three have all been hybrids and each time I have upped the turbo size, the BHP power has gone up accordingly! I know full well that the turbo adds considerably to the overall power output of the car, but I can't help wondering sometimes, what the standard power would be without the turbo's assistance? One of life's little mysteries I guess

You can have an educated guess by looking at the power output of the na version of yours - did Saab do an na 2.0?

Or if not, look at the average 2.0 na engine from the same era as your car.

Take mine, it's a 1.9TDI, with 130bhp from the factory and 170 with my remap but looking at the power output of the 1.9SDI engine I know that without the turbo and intercooler my base power is 67bhp.

 

[HDi fun]

I think we're at cross purposes here. The turbo doesn't produce any bhp directly. It is not connected to the drive train. All it does is to use exhaust gas to drive a compressor which forces more air into the engine.

Correct! And what your left with is what bhp the engine can produce.


.....

I have kind of lost my way of thought of this chatt. I cant get out in words, what my head is thinking....... Never mind. What ever I put down, makes me sound like I'm going against turbo's, witch of corse, is not the case. Sod it. I'll stop talking

 

[T9 man]

You can have an educated guess by looking at the power output of the na version of yours - did Saab do an na 2.0?

Or if not, look at the average 2.0 na engine from the same era as your car.

Take mine, it's a 1.9TDI, with 130bhp from the factory and 170 with my remap but looking at the power output of the 1.9SDI engine I know that without the turbo and intercooler my base power is 67bhp.

They did Yugguy but that was a long long time ago! There are no NA engines from my car era i'm afraid. All there base models are even turbocharged

 

[HDi fun]

The SDI was around until about 2004. But the TDi isn't simply the SDi with a turbo bolted on.

My 406 was about 190bhp with a remap. Take off the turbo and you'd be lucky to see 50bhp.

Your car would be similar without the turbo, it would have much less than the SDi's 67bhp.

 

[bigbadjoe]

I think we're at cross purposes here. The turbo doesn't produce any bhp directly. It is not connected to the drive train. All it does is to use exhaust gas to drive a compressor which forces more air into the engine.

:bigsmile: Yeah, thanks. That's what I was trying to say!

Couldn't get the words out! lol

 

[MasterAuron]

Not only that, most turbocharged versions of an N/A engine are lower compression meaning that without the turbo they would produce less power than their N/A conterparts.

 

[HDi fun]

Not only that, most turbocharged versions of an N/A engine are lower compression meaning that without the turbo they would produce less power than their N/A conterparts.

Already been there a couple of posts back when comparing VW's TDi and SDi engines.

My 406 played up once after driving through water and I couldn't believe how slow they are in limp home mode.

320lbft remapped, I honestly think it was delivering no more than 50-60lbft without no boost.

 

[MasterAuron]

Yes but you didn't explain why.

 

[claymore]

i suppose i would have to chose boost over NA

 

[SLEEPER]

Re the point about a turbo not producing power , It does because If the engine produces less without it surely it has a direct effect on the power output which is what I thought tuning was about.

The idea that all it supplies is air may be correct but by the same reasoning
any induction wouldnt count

And again using that logic an exhaust is the same because as its after the engine all it does it get rid of gases

You could maybe even continue with injectors or fuel injection on an na engine whats the difefrence between more air and more petrol - you need both for more power

 

[HDi fun]

Yes but you didn't explain why.

No, I didn't. :embarrest:

I think what we're driving at here is that turbocharged engines are substantially different from the naturally aspirated counterparts from which they are derived.

PSA has never made an HDi engine without turbocharging so it had no chance at all in limp home mode (good job home wasn't up a 1 in 5 gradient ). The geometric compression ratio of the 2.2 HDi was about 17.9:1

Non-turbo diesels are usually more like 23:1 or higher still, which is the point I think you are putting across. Even so they're pretty spineless to drive.

Our 1.9D Seat was brilliant off the line (ie up to about 5mph) - instant torque at idle. The downside was that things went rapidly downhill from about 1100rpm up

 

[Dan2587]

Diesels are crap without turbo.I used to like the turbo on my old rover diesel when it kicked in but i have never drove a petrol turbo to compare.

 

[HDi fun]

Diesels are crap without turbo.I used to like the turbo on my old rover diesel when it kicked in but i have never drove a petrol turbo to compare.

Some are crap with turbos

 

[bigbadjoe]

Some are crap with turbos

A lot of old ones were. I know my first car. A 1.8td escort. The turbo in that was like old people having sex. Slow and awkward.

Where as the modern ones are just as bad, becuase they are set up to save you fuel, and get 50+ mpg.

 

[obi_waynne]

It's also worth mentioning that an engine with a turbo on it that isn't boosting is causing a massive restriction in the air flow as the air tries to get around the impellors.

 

[turbonutter69]

A lot of old ones were. I know my first car. A 1.8td escort. The turbo in that was like old people having sex. Slow and awkward.

Where as the modern ones are just as bad, becuase they are set up to save you fuel, and get 50+ mpg.

That would be the non intercooled version?
I had one for about a week before I sold it on.