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Turbo vs V6 in the mountains - Which has more power?
Posted: Thu Mar 04, 2010 9:14
by mogulman
I'm going to be getting a new car later in the year (Mazda or something else). The last few cars I've had are Turbo 4 Cylinder engines. Currently have a Saab(aru) 9-2x Aero (same as a Subaru WRX) and a Mazda CX-7 2007.
We travel through the mountains a lot. I was told that Turbo cars lose less power at high altitude then normally aspirated engines.
So I was wondering.. If I get a car that has the same rated HP (around 250). Would I be better off getting a 4-cylinder Turbo or a 6-Cylinder?
I don't really car about Turbo lag. I'm used to that. Really just wondering about power at higher altitudes.
Posted: Thu Mar 04, 2010 9:14
by Eclipse
It depends, certain turbo systems (like the srt) are actually built to run MORE boost at higher altitudes, making them monsters in the hills.. the mazda turbo systems are more typical, you will see upwards of 20% power loss at higher altitudes. However, I would think generally, the turbo 4cyl would have an advantage over a v6 with the same HP rating in the mountains.
Posted: Thu Mar 04, 2010 9:14
by I`m Batman
The turbo car is much better in the mountains... no contest.
I had a V6 car and it had a hard time in the mountains.
My brother used to have a Jetta 1.8T and that thing flys up the mountain. Same goes for my friends 2000 WRX.
Posted: Thu Mar 04, 2010 9:14
by Stealth01
I can give you an apples-to-apples comparison.
I used to own a 2004 6S (V6). In the mountains, it became very sluggish and you could tell it was struggling to breathe. Now, in the MS6, the effect is not NEARLY as bad, and while it still loses power, it's still fun to drive in the mountains.
Posted: Thu Mar 04, 2010 9:14
by tbot
I can attest to the mazda differences. I know the both when Bree and I had our NA mazdas (her a v6 6s and me a 4 banger 3i) we would always have issues in the mountains even more so than the speeds did. So far, my speed6 hasn't had much of an issue. I do notice some loss, but its no where near what it was like w/ NA.
Posted: Thu Mar 04, 2010 9:14
by erod550
Is there turbo lag in a turbo 4 cylinder? hehe. It's not really noticeable in most turbo 4 cylinders unless you upgrade the turbo. At altitude I will always go with a turbo 4 over an N/A 6. Maybe even over an N/A V8 depending on what kind of car it's in (weight).
Posted: Thu Mar 04, 2010 9:14
by GR-8
Turbo definitly. It will pull up the hills with ease.
Posted: Thu Mar 04, 2010 9:14
by chickenwafer
Like others have said, the turbo in the altitude is the great equalizer.
Where a torquey V6 sounds great, it will struggle for air in the mountains. The turbo will just spin faster, creating the same boost (but compressing less dense air) so the power drop is not nearly as significant.
Posted: Thu Mar 04, 2010 9:14
by erod550
tbot wrote:I can attest to the mazda differences. I know the both when Bree and I had our NA mazdas (her a v6 6s and me a 4 banger 3i) we would always have issues in the mountains even more so than the speeds did. So far, my speed6 hasn't had much of an issue. I do notice some loss, but its no where near what it was like w/ NA.
Part of the problem there is that they also had significantly less HP than the speeds to start with. Even at sea level neither car would have been able to keep up with a speed, especially not a regular 3 that has 115hp less than a Speed not even taking the effects of altitude into consideration.
As a closer comparison, I raced a lot of Camaro Z28s and SSs (late 90s early 2000s, before the new ones came out) and they have 300hp at sea level. My SRT-4 with a lot less hp (220hp/265tq uncorrected at the wheels with a few mods) was faster than the Camaros because they lost so much HP due to the altitude that they were putting down less than I was, even though at sea level they'd have a lot more power. And this is at 5-6k feet. Go up into the mountains and the difference gets even worse.
Posted: Thu Mar 04, 2010 9:14
by Stealth01
erod550 wrote:Part of the problem there is that they also had significantly less HP than the speeds to start with. Even at sea level neither car would have been able to keep up with a speed, especially not a regular 3 that has 115hp less than a Speed not even taking the effects of altitude into consideration.
As a closer comparison, I raced a lot of Camaro Z28s and SSs (late 90s early 2000s, before the new ones came out) and they have 300hp at sea level. My SRT-4 with a lot less hp (220hp/265tq uncorrected at the wheels with a few mods) was faster than the Camaros because they lost so much HP due to the altitude that they were putting down less than I was, even though at sea level they'd have a lot more power. And this is at 5-6k feet. Go up into the mountains and the difference gets even worse.
Yep. That's why I can walk a stock 350Z or Mustang GT at this altitude. If I lived at sea level, I'd be driving something different, but I live at 7000 feet in elevation. FI FTW
Posted: Thu Mar 04, 2010 9:14
by tbot
erod550 wrote:Part of the problem there is that they also had significantly less HP than the speeds to start with. Even at sea level neither car would have been able to keep up with a speed, especially not a regular 3 that has 115hp less than a Speed not even taking the effects of altitude into consideration.
As a closer comparison, I raced a lot of Camaro Z28s and SSs (late 90s early 2000s, before the new ones came out) and they have 300hp at sea level. My SRT-4 with a lot less hp (220hp/265tq uncorrected at the wheels with a few mods) was faster than the Camaros because they lost so much HP due to the altitude that they were putting down less than I was, even though at sea level they'd have a lot more power. And this is at 5-6k feet. Go up into the mountains and the difference gets even worse.
You complete and totally missed the point there. I wasn't comparing car to car, i was comparing the noticeable loss of power for each car based on the difference of NA vs FI.
Posted: Thu Mar 04, 2010 9:14
by Stealth01
^^^ And in that case, the FI car definitely loses less power as altitude increases.
Posted: Thu Mar 04, 2010 9:14
by bmwzoom
tbot wrote:I can attest to the mazda differences. I know the both when Bree and I had our NA mazdas (her a v6 6s and me a 4 banger 3i) we would always have issues in the mountains even more so than the speeds did. So far, my speed6 hasn't had much of an issue. I do notice some loss, but its no where near what it was like w/ NA.
Agreed. My 6s was like driving on tar in the mountains, yet Tbot's 3i was actually quicker than my 6s in the mountains, I am sure this was because of the weight issue. I have only taken my MS3 in the mountains a couple of times and see no problem with its power. Then again I am going from driving on tar to driving on butter.

How's
that for an analogy?!
Posted: Thu Mar 04, 2010 9:14
by Stealth01
bmwzoom wrote:Agreed. My 6s was like driving on tar in the mountains, yet Tbot's 3i was actually quicker than my 6s in the mountains, I am sure this was because of the weight issue. I have only taken my MS3 in the mountains a couple of times and see no problem with its power. Then again I am going from driving on tar to driving on butter.

How's
that for an analogy?!
I think I might rather drive on tar. Butter makes it hella slippery.

Posted: Thu Mar 04, 2010 9:14
by bmwzoom
Stealth01 wrote:I think I might rather drive on tar. Butter makes it hella slippery.

haha! True, but ya know what I mean
