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It might be 6800 on the Mazdaspeed 3, but the NA 3s you can rev out to 7,200rpms and probably should...so that drops the 1-2 shift to almost spot on 4,000rpms which is close to perfect.

That said it would be nice to have the gear set for (at 7200rpms)
1st 36mph
2nd 62mph
3rd 90mph
4th 120mph
5th 170mph

Supposing a 5 speed and the powerband of our engines. Everything in 1-4th just a little bit closer together. For a 6spd the current 2010 6spd is just about perfect, though I'd have 3-5 just a bit shorter.

If I had to put a number on it I'd say the 6spd probably isn't more then 10lbs heavier then the 5spd, probably less. the Case only needs to be a hair bigger, and it might be the same size between the 2010 5 and 6spds. If I do get a later model Mazda 3 it'll probably be a 2.0...but I am going to be considering getting a 6spd off a junker...pretty seriously. It would be nice if they offered it as an option, I'd certainly pay more for it. But I want the fuel economy of the 2.0. Though I'd also like DSI and some real engine tweaking. Mazda I know you can hear me, I can't believe you can't manage 80hp/l on the 2.0 and at least 72hp/l on the 2.5 (IE 160hp 2.0 and 180hp 2.5) without serious compromises. Give us those numbers and we shall be happy (till we start tearing in to the cars to get even more power).

I get that as engines get bigger they get less efficient, but the 2.0 is 74hp-l, not terribly shabby, but certainly not overly impressive for the year 2009 (the civic is managing about 79hp-l, the RSX 80hp-l), the 2.3 with 156hp was ~68hp-l, quite a bit of drop off from the 2.0's efficiency and the 2.5 is ~67hp-l a further drop. I am thinking that the biggest difference in efficiency between the 2.0 and 2.3/2.5 is the balance shaft and probably secondarily the drop in compression ratio. I can see the need of 'smoothness' to be 'class leading', but why drop the compression ratio? Was it because it really couldn't run on regular gas otherwise?

It'd be nice to see a real 3s or even a Mazda 3r. I know there is the Mazdaspeed 3, but why not do some 'basics' to the Mazda 3 that would be cheap to improve performance from the factory. No balance shaft, maybe tweaked cams and engine maps, maybe a revised exhaust. Even if you didn't do revised exhaust the difference in manufacturing for no balance shaft (basically a BSD from the factory), one or two different cams and the engine maps couldn't possibly cost more then $300-500 for Mazda. Charge $1,000-2,500 for it and I bet people why buy. Maybe better exhaust (still quite) might add $100-300 per vehicle from the factory (well cost to Mazda) and still maybe call it only $1,500-2,500 MSRP increase.

Mazda 3r 2.5l, 175hp or maybe 180hp for the tweaked exhaust at only call it a $2,000 premium. Hey, other perk it would probably also get 1-2mpg better. Give me those power levels (oh and hey an extra 1-2mpg) and I would deffinitely get a 3r over a 3i. Until then, a 6spd and 19hp for a vehicle weighing 100lbs more isn't all that significant a performance boost. Hell compared to my 2005 3i a 6spd and 19hp isn't a lot for weighing 300lbs more in fact my 2005 with 148hp and 2696lbs comes out to about 18.2lb-hp, the 2010 2.5 with 167hp and 2968lbs is 17.7lbs-hp, even with all that extra torque ends up being only a little faster (the 2010 3i weighs in at around 2870lbs, so the 3s in that case is a fair amount faster since it is only a 100lb weight difference).

Still ranting here, sorry, but that is my either gripe...the curb weights, especially with no increase in output efficiency. The 3i is now quite a bit slower then the old one, 200lbs of extra fat on the car means it is probably something like half a second slower 0-60 then the old 3i was. By a consquence, ignoring the 6spd in the 2010 3s, all the extra weight means the 2.5l is/would be only a hair faster, maybe 1-2 tenths, despite the extra 2 tenths of a liter and 11hp. With the shorter gearing from the 6spd it is probably more like .2-.3s faster 0-60, but still a pretty small bump up. If it weighed the same we'd be talking a car that would hit 0-60 probably close to a full second faster, especially with the 6spd having shorter gears.

I really hope DSI and lighter curb weights are in the cards for the next generation for Mazda 3 (around when I'll be buying one, in 4-6 years). Mazda at least is claiming both.
-Matt
 

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[quote author=azazel1024 link=topic=159743.msg3395641#msg3395641 date=1256996220]
It might be 6800 on the Mazdaspeed 3, but the NA 3s you can rev out to 7,200rpms and probably should...so that drops the 1-2 shift to almost spot on 4,000rpms which is close to perfect.

That said it would be nice to have the gear set for (at 7200rpms)
1st 36mph
2nd 62mph
3rd 90mph
4th 120mph
5th 170mph

Supposing a 5 speed and the powerband of our engines. Everything in 1-4th just a little bit closer together. For a 6spd the current 2010 6spd is just about perfect, though I'd have 3-5 just a bit shorter.

If I had to put a number on it I'd say the 6spd probably isn't more then 10lbs heavier then the 5spd, probably less. the Case only needs to be a hair bigger, and it might be the same size between the 2010 5 and 6spds. If I do get a later model Mazda 3 it'll probably be a 2.0...but I am going to be considering getting a 6spd off a junker...pretty seriously. It would be nice if they offered it as an option, I'd certainly pay more for it. But I want the fuel economy of the 2.0. Though I'd also like DSI and some real engine tweaking. Mazda I know you can hear me, I can't believe you can't manage 80hp/l on the 2.0 and at least 72hp/l on the 2.5 (IE 160hp 2.0 and 180hp 2.5) without serious compromises. Give us those numbers and we shall be happy (till we start tearing in to the cars to get even more power).
-Matt
[/quote]
1st Gear ought to be taller so there isn't such a sharp drop in revs from 1st to 2nd. I don't know about you all, but when I'm in traffic, waiting for the revs to drop between 1st and 2nd, I almost get rear ended by impatient automatic drivers.
 

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Just a hair shorter isn't going to make much difference. I am talking like 3-5% shorter 1st gear, but about 10-12% shorter 2nd gear. Means the 1-2 shift at 7,200rpms would likely drop you around 4,300rpms instead of about 4,000 that it is now.
-Matt
 

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some of those nsn taller fifths should be floating around.

i was driving in a sunfire gt yesterday and was amazed that at 120 kmph he was only turning 2500 rpm. talk about gas mileage, a full 1000 rpm diff.
 

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[quote author=candal82 link=topic=159743.msg3394528#msg3394528 date=1256918306]
p.s. do we know what the weight difference is between the two boxes? Just because it is a 6 spd, does not necessarily mean it's heaver than the 5 spd. Many variables here... I think Aisin manufactures the 6spd from the MS3? I'll see if I can get a weight comparo.

As for performance, I think it will be great for an N/A vehicle, especially on a road course.
[/quote]

i cant find it now, but i remember reading that the 6-speed box is substantially heavier than the 5-speed.

you can read through to see if you can find it, lots of good info in there too:
http://www.specialstage.com/forums/showthread.php?t=30459
 

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:shock: Damn so w/o my speed limiter I can take my 3 up to 162-170mph?
 

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[quote author=ryukensfj link=topic=159743.msg3395906#msg3395906 date=1257016271]
:shock: Damn so w/o my speed limiter I can take my 3 up to 162-170mph?
[/quote]

nope. Just because a car has the gearing to do it, does not mean it can. Most cars in this power range are drag/power limited
 

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Discussion Starter · #29 ·
[quote author=azazel1024 link=topic=159743.msg3395666#msg3395666 date=1256998279]
Just a hair shorter isn't going to make much difference. I am talking like 3-5% shorter 1st gear, but about 10-12% shorter 2nd gear. Means the 1-2 shift at 7,200rpms would likely drop you around 4,300rpms instead of about 4,000 that it is now.
-Matt
[/quote]

Yeah, I'm not sure why I used 6800. I must have been smoking crack lol. I'll also revise max engine rpm when I input the 2010 gearbox data. Is the rev limiter at 7000 or 7200 rpm? I could swear my car's limiter is 7000...
 

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[quote author=Eternal link=topic=159743.msg3396100#msg3396100 date=1257028339]
[quote author=ryukensfj link=topic=159743.msg3395906#msg3395906 date=1257016271]
:shock: Damn so w/o my speed limiter I can take my 3 up to 162-170mph?
[/quote]

nope. Just because a car has the gearing to do it, does not mean it can. Most cars in this power range are drag/power limited
[/quote]

You sure I'm drag/power limited and won't be able to go up to what my gearing says I can?
 

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[quote author=Eternal link=topic=159743.msg3396242#msg3396242 date=1257036177]
I posted it without looking at your mods. You should be able too!! My comment was toward a stock mazda 3.
[/quote]

lol thanks. good to know how fast I can actually go, when someone figures out how to disable the speed limiter on 07+ models.
 

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You probably can get up that fast or close to it. The Mazdaspeed 3 can deffinitely hit its 155mph limiter. I think 160mph if you are putting 240+ to the ground is well within the realm of possible.

Don't know about the newer Mazda 3, but the older 2.0 and 2.3 are deffinitely 7,200rpms.

120km/hr also known in civilized parts of the world as 75mph :lol: is about 3,300-3,400...close sure, but not exactly 1,000rpm difference. At any rate, the sunfire needs it cause it is a fricken fuel hog engine otherwise.

Imagine what our milage would be with a 5th gear 20% longer (say 2,800rpms at 75mph). I'd bet highway milage would go up at least 2mpg, maybe 3mpg. Of course the car would be a heck of a less responsive in 5th gear...deffinitely wouldn't be shifting to 5th gear at 35mph, more like 40 (so cruising around town would maybe use a bit more because of staying in 4th longer).
-Matt
 

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Discussion Starter · #34 ·
Ok,

I've finally updated the analysis. I've included the 2010 manual gearboxes, assuming they can be retrofited to the 2004-2009 Mazda 3. Maximum engine RPM is set at 7000 rpm (this is the rev limiter on my 2006 2.3).

For outright performance, I'd still go with the 1st gen Mazdaspeed3 6spd if I had the choice. It has the most aggressive ratios while still having a pretty decent 6th gear for highway cruising.





 

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i think second is so tall in the normal 3 because it's an econo-box... guess they wanted to get goo city fuel economy by letting people keep it in second when in the city, speeds like 25-30mph
 

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[quote author=biped link=topic=159743.msg3400268#msg3400268 date=1257299583]
second doesn't seem so tall if you flat shift

matt i was off by 100 rpm sue me
[/quote]

So I shall! Your statements have been entered and shall be used against you in a court of eWang comparison!

:)
-Matt
 

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[quote author=Verto link=topic=159743.msg3400135#msg3400135 date=1257294257]
i think second is so tall in the normal 3 because it's an econo-box... guess they wanted to get goo city fuel economy by letting people keep it in second when in the city, speeds like 25-30mph
[/quote]

Keeping in 2nd at those speeds would greatly reduce fuel economy. I normally shift into 2nd around 10mph, 3rd 18-20mph, 4th 25-30mph and 4th 35mph. That is supposing I am cruising/accelerating slowly. You are probably right that it was in part for fuel economy and reduced shifting in the city more then it was about performance. I do really like the look of those 2010 6spd gears (non MS).
-Matt
 
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