Mazda6 Signature

I think they have mucked it up. 227 on regular, 250 on premium

2018 Mazda6 Gets 250 HP Turbo Treatment, New Interior For LA Debut

"Yes, the Mazda6 is finally gaining some much needed oomph in the form of the company’s boosted 2.5-liter four-cylinder. In the 6, the engine makes 250 horsepower (186 kW) and a full 310 lb-ft. (420 Nm) of torque. It runs what the automaker calls a Dynamic Pressure Turbo, using a small inlet to spool the turbine quicker at low engine RPM with a larger passage opening at higher speeds. The result, Mazda says, is nearly instantaneous boost, and as long as you run 93 octane fuel, you’ll get the full monte. Lower octane gas doesn’t hurt the car, but it does drop the power to 227"

Yes, I thought it was the same engine as the CX-9. They should say that it needs premium fuel and not mention the 227 number.
 
Yeah an LSD or AWD would be preferred... my '02 Maxima (255hp) would literally go sideways if you jumped on it too fast from a dead stop with that open diff in the front. That vehicle was one reason I got my G35 in AWD form.
 
Yeah an LSD or AWD would be preferred... my '02 Maxima (255hp) would literally go sideways if you jumped on it too fast from a dead stop with that open diff in the front. That vehicle was one reason I got my G35 in AWD form.

The RWD G35 can handle the 3.5L, but a Maxima with an open diff? No way. Thats like comparing apples to oranges. The Maxima needs AWD or at least an LSD, while the G35 will be able to handle that sort of power a lot better with easy to control oversteer.

Anyways, I just bought a 1995 Maxima winter heater and the Canadian 5 speed manual versions came with an LSD, and the handling is excellent. This chassis can easily handle roughly 220hp and 220ft/lb of torque, but anything more than a 3L and youre gonna want the balance of a RWD vehicle.

Having sampled an LSD, all I can say is that I wish more manufacturers offered one as a sport package with lowered suspension or something of the sort. Older BMWs with the sport versions came with an LSD, but they omitted such an option with the more recent models I assume to leave space for the M performance models, because with well tuned vehicles like a Mazda, BMW, Honda Nissan etc youd be very surprised how well an otherwise stock car will corner with an LSD and coilovers.
 
Yes, I thought it was the same engine as the CX-9. They should say that it needs premium fuel and not mention the 227 number.

It is the same engine. Why state a requirement for premium when it doesn't need it? Most people only want to run regular, especially when you're not driving a luxury badge. It's a good strategy to let owners decide how much peak power they want.

I've only been running regular in my CX-9 and can't imagine needing more power which would only be noticed if you went balls to the wall on the highway. It merges on the highway and gets to 90 mph in a quiet, smooth, and very quick rush at low RPM. Anything more and I'd lose my licence.
 
It is the same engine. Why state a requirement for premium when it doesn't need it? Most people only want to run regular, especially when you're not driving a luxury badge. It's a good strategy to let owners decide how much peak power they want.

I've only been running regular in my CX-9 and can't imagine needing more power which would only be noticed if you went balls to the wall on the highway. It merges on the highway and gets to 90 mph in a quiet, smooth, and very quick rush at low RPM. Anything more and I'd lose my licence.

Id be using an ethanol-free blend 91 octane fuel on any vehicle that can adapt to a higher octane fuel - the benefits are definetely there.

Generally, If you are revving the car hard, towing/hauling people and cargo, driving in hot weather, particularly up/down hills with cargo in the car, youre going to want 91. 87 octane becomes less efficient in hot weather with people in the car because you need to rev the car harder.

As long as you are using ethanol-free fuel, you will make all of your money back with fuel savings anyways. Ethanol blended fuel is really inefficient. If your car works with 91, always best to take fuel advantage, but only if you can find ethanol-free. (Eg. Canadian shell stations have ethanol-free 91, and it is very, very good fuel)
 
I’d be using an ethanol-free blend 91 octane fuel on any vehicle that can adapt to a higher octane fuel - the benefits are definetely there.

Generally, If you are revving the car hard, towing/hauling people and cargo, driving in hot weather, particularly up/down hills with cargo in the car, you’re going to want 91. 87 octane becomes less efficient in hot weather with people in the car because you need to rev the car harder.

As long as you are using ethanol-free fuel, you will make all of your money back with fuel savings anyways. Ethanol blended fuel is really inefficient. If your car works with 91, always best to take fuel advantage, but only if you can find ethanol-free. (Eg. Canadian shell stations have ethanol-free 91, and it is very, very good fuel)


Is 91 the highest you guys get? We have 94 in New England and many other areas of the US.
 
Is 91 the highest you guys get? We have 94 in New England and many other areas of the US.

Ive seen 93/94 all over Canada, but based on my findings and what others have told me at a tuning shop, the ethanol-free 91 octane shell fuel we have here gave me better power gains then any ethanol blended 93/94 octane fuel.

Use 87 or 91, (although 91 is definitely best for turbo engines) but just look for ethanol free.
 
Note though... that Honda Civic Type R in video has the following:

"Helical Limited-Slip Differential
Powerful performance cars with conventional "open" differentials can suffer from excessive wheel spin, particularly from the inner drive wheel when cornering. The Civic Type R's helical-type limited-slip differential (LSD) helps insure that excessive wheel spin doesn't happen, by putting more of the engine's power effectively to the pavement. Under power, the limited-slip differential works to equalize the speed of the two drive wheels. The system never locks the speed of the two drive wheels together as would a locking differential, but instead allows different wheel speeds to accommodate the longer distance the outer wheel must travel when cornering. The LSD allows the Type R to accelerate harder on surfaces with uneven traction, to generate reduced wheel spin when exiting corners, and to enhance the vehicle's responsiveness to throttle inputs in corners. The term "helical" describes the way the differential's gear teeth are cut – which is at an angle to the gear's shaft. Helical gears are quieter in operation and can transmit greater torque than straight-cut (or spur) gears."

http://news.honda.com/newsandviews/article.aspx?id=9740-en
 
https://youtu.be/Gw5-lVlzNoY

This explains torque steer and also how you can eliminate it without awd.

BTW Mazda rep at LA auto show said zero torque steer, I guess we shall wait and see.

Seperating the steering from the suspension is the main way to eliminate torque steer, but an LSD is also helpful (Ford has a version in the focus RS called REVOknuckle and the new civic type R has something similar)

Note though... that Honda Civic Type R in video has the following:

"Helical Limited-Slip Differential
Powerful performance cars with conventional "open" differentials can suffer from excessive wheel spin, particularly from the inner drive wheel when cornering. The Civic Type R's helical-type limited-slip differential (LSD) helps insure that excessive wheel spin doesn't happen, by putting more of the engine's power effectively to the pavement. Under power, the limited-slip differential works to equalize the speed of the two drive wheels. The system never locks the speed of the two drive wheels together as would a locking differential, but instead allows different wheel speeds to accommodate the longer distance the outer wheel must travel when cornering. The LSD allows the Type R to accelerate harder on surfaces with uneven traction, to generate reduced wheel spin when exiting corners, and to enhance the vehicle's responsiveness to throttle inputs in corners. The term "helical" describes the way the differential's gear teeth are cut – which is at an angle to the gear's shaft. Helical gears are quieter in operation and can transmit greater torque than straight-cut (or spur) gears."

http://news.honda.com/newsandviews/article.aspx?id=9740-en

That’s a good way to describe an LSD. It’s an overall far better design then any open diff and it makes a big difference. It helps a lot in rain or snow, especially when eliminating tire spin during aggressive throttle off the line, not just around corners.
 
Our RON octane is the same as Europe's I believe. So:

Aus 91RON (regular unleaded) = USA 87
Aus 95RON (premium unleaded) = USA 91
Aus 98ROM (premium unleaded) = USA 93.5

So here the 2.5T (in the CX-9) is rated as 227bhp on 91 RON and may make 250 on 95/98 but Mazda Australia doesn't mention this.

Should be the same in 2.5T Mazda 6
 
Our RON octane is the same as Europe's I believe. So:

Aus 91RON (regular unleaded) = USA 87
Aus 95RON (premium unleaded) = USA 91
Aus 98ROM (premium unleaded) = USA 93.5

So here the 2.5T (in the CX-9) is rated as 227bhp on 91 RON and may make 250 on 95/98 but Mazda Australia doesn't mention this.

Should be the same in 2.5T Mazda 6

I believe it was 227hp on 87 and 250 on 91 octane, no?
 
https://youtu.be/Gw5-lVlzNoY

This explains torque steer and also how you can eliminate it without awd.

BTW Mazda rep at LA auto show said zero torque steer, I guess we shall wait and see.

AWD is mainly desirable for maximizing traction. The reduced torque steer is just a side benefit.

Seperating the steering from the suspension is the main way to eliminate torque steer, but an LSD is also helpful (Ford has a version in the focus RS called REVOknuckle and the new civic type R has something similar)

A limited slip differential in a FWD car makes torque steer worse, not better. Think about it. Torque steer results from unequal forces at the front contact patches. An open differential is designed to apply equal torque to both axles. A LSD is designed to allow un-equal torque at the axles.

Edit: I think the revised steering knuckle design that's resistant to torque steer is probably what allowed Ford and Honda to use a LSD in the Focus RS and Civic Type R. My Focus ST doesn't have the RevoKnuckle. It uses ESC (braking) with an open diff to get torque to the outside wheel, rather than an LSD. Even with that setup, they needed to add electric steering assist to counter torque steer.
 
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AWD is mainly desirable for maximizing traction. The reduced torque steer is just a side benefit.



A limited slip differential in a FWD car makes torque steer worse, not better. Think about it. Torque steer results from unequal forces at the front contact patches. An open differential is designed to apply equal torque to both axles. A LSD is designed to allow un-equal torque at the axles.

Edit: I think the revised steering knuckle design that's resistant to torque steer is probably what allowed Ford and Honda to use a LSD in the Focus RS and Civic Type R. My Focus ST doesn't have the RevoKnuckle. It uses ESC (braking) with an open diff to get torque to the outside wheel, rather than an LSD. Even with that setup, they needed to add electric steering assist to counter torque steer.

My V6 Maxima doesn’t have a hint of torque steer and it has an LSD. It’s a 1995 model.
 
Hmm, those 4th gen Maximas were known for torque steer. Try this: stop somewhere where the road has some crown. Take your hands off the wheel, and try a hard launch. If it doesn't try to steer you off the road, I'll be surprised.
 
Hmm, those 4th gen Maximas were known for torque steer. Try this: stop somewhere where the road has some crown. Take your hands off the wheel, and try a hard launch. If it doesn't try to steer you off the road, I'll be surprised.

If I take my hands off the wheel they probably will torque steer especially because the steering in this vehicle is very light effort, but I dont ever recall having the fight the wheel at WOT in first gear - even if Im holding it one handed. You might be thinking about the next generation of maximas which came fitted with a 3.5L. Now the 3L that I have in my car I feel like is totally manageable for a FWD car, the Nissan handles the power quite well. The tires dont slip or even make so much as a chirp while cornering or accelerating hard in wet conditions.
 
LSD on a high powered FWD car does not mitigate torque steer. At certain times, it might even make you think that you have torque steer, when in fact it is just the LSD routing power to the tire with the most traction or where your steering wheel is pointed. An example of this is the funny overtaking maneuver we do while driving a Mazdaspeed3. If you want to pass someone quickly on the highway, turn the steering wheel slightly to the left or right (based on where you want to pass), then just go WOT. The LSD will cause your car to change lanes by itself LOL.

Edit: Since we now know that the 2018 Mazda6 is not getting AWD, it definitely needs to come with LSD.
 
The RWD G35 can handle the 3.5L, but a Maxima with an open diff? No way. That’s like comparing apples to oranges. The Maxima needs AWD or at least an LSD, while the G35 will be able to handle that sort of power a lot better with easy to control oversteer.

Not really apples to oranges at all.... a Journey (V36) model with a rear open diff would have been just as performance neutered. If you go RWD on a V36 you want a sport model with the VLSD.
 
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