'07 GTI, Si, and MazdaSpeed 3 dyno tests.

[siegen]

They weren't too happy with the 3, the power delivery is apparently not very linear (look at the dyno chart), despite the large peak numbers. If you aren't between 3,000rpms and 5,500 rpms, there is considerably less TQ being made.

Full Article

[regfootball]

the Mazda3 still spanks the civic. so does the cobalt, BTW. WRX does also.

[Northstar]

The Civic's dyno chart is hilarious. It doesn't get to more than 100HP before 4500rpm, and it's at less than 130HP at 5700rpm.

[pow]

And, yay, GTI wins for being the most powerful one with a linear delivery.

All reports I've read indicate that the Mazda Mazdaspeed Mazda3 (or is it Mazda Mazda3 Mazdaspeed?) has too much power for its own good.

[siegen]

the Mazda3 still spanks the civic.  so does the cobalt, BTW.  WRX does also.

204650[/snapback]

You really are one-track minded aren't you?

The Mazda3 makes big peak TQ and HP numbers, but has a poor powerband. It will be fast in a straight line, but the GTI would probably beat it around the track. Where the 3 keeps falling out of its powerband, the GTI will pull strong. The Civic Si has the nicest looking powerband and makes 85% of its peak TQ from 2k to 8k rpms, if it only had .2L or .4L more displacement...

The Civic's dyno chart is hilarious. It doesn't get to more than 100HP before 4500rpm, and it's at less than 130HP at 5700rpm.

204652[/snapback]

Also remember the Civic Si weighs 250-400 lbs less than these other two. The Ariel Atom uses an almost identical engine out of the Civic Type R and it isn't slow by any means.

[ToniCipriani]

Also remember the Civic Si weighs 250-400 lbs less than these other two. The Ariel Atom uses an almost identical engine out of the Civic Type R and it isn't slow by any means.

204657[/snapback]

Same series, not the exact same engine. The Type-R engine is a K20Z1, and the Si a K20Z3.

[Northstar]

The Mazda3 makes big peak TQ and HP numbers, but has a poor powerband. It will be fast in a straight line, but the GTI would probably beat it around the track. Where the 3 keeps falling out of its powerband, the GTI will pull strong. The Civic Si has the nicest looking powerband and makes 85% of its peak TQ from 2k to 8k rpms, if it only had .2L or .4L more displacement...

Also remember the Civic Si weighs 250-400 lbs less than these other two. The Ariel Atom uses an almost identical engine out of the Civic Type R and it isn't slow by any means.

204657[/snapback]

How is it the nicest? It has no power until you get to 6k rpm. That's nice for daily driving?

At 3.5k rpm, you're making 160HP in the 3. 160HP doesn't come until after 6200rpm in the Si.

Maybe I'm being a bit harsh since the Si is a 4cyl and I'm used to a dyno chart that looks something like this:

I actually didn't realize the torque curve was that flat, but I do now.

[siegen]

Same series, not the exact same engine. The Type-R engine is a K20Z1, and the Si a K20Z3.

204659[/snapback]

That's why I said almost identical.

How is it the nicest? It has no power until you get to 6k rpm. That's nice for daily driving?

It is the most flat, which is ideal. It just lacks in displacement.

[Northstar]

It is the most flat, which is ideal. It just lacks in displacement.

204689[/snapback]

The torque is pretty flat, but the HP is not. When you say "powerband" it sounds more like HP than torque.

[ocnblu]

To get the advertised horsepower out of the Civic, rev the pee out of it, then get 17 mpg... from "the most fuel efficient car company in America".

[siegen]

The torque is pretty flat, but the HP is not. When you say "powerband" it sounds more like HP than torque.

204690[/snapback]

Powerband referes to the TQ curve as that shows what work the engine is actually doing. The HP curve is derived from the TQ curve (hp = tq * rpm / 5252) and isn't a real number that your car produces (so to speak) but more of a helper equation designed to show how a car accelerates . Having a flat TQ curve means acceleration increases at a constant rate and doesn't drop off or surge. It is very important for a race car as sudden changes in the TQ curve (dips or surges) can cause instability while accelerating. It's funny cause Honda generally tunes their vtec engines to have a slightly abrupt vtec crossover, which would actually be bad on a race track (you can see the abrupt crossover on the Civic Si's dyno in the article). They do it though as it feels cool I guess for all the "Vtec Yo!" kids.

The flat TQ curve, among other things, in almost all Honda vtec engines is why every review you read of them talks about how they love to rev and rev easily. It's because the TQ doesn't drop off like most N/A (naturally aspirated) 4cyl engines do around 5k-5.5k rpms.

I'm not saying the GTI has a bad TQ curve though, just the 3. The GTI's is pretty good, even though the TQ does drop off steadily, it doesn't suddenly come on and then drop off abruptly like the 3.

[CaddyXLR-V]

They weren't too happy with the 3, the power delivery is apparently not very linear (look at the dyno chart), despite the large peak numbers. If you aren't between 3,000rpms and 5,500 rpms, there is considerably less TQ being made.

Full Article

204431[/snapback]

The 3 hits the Civics peak torque number at around 2200rpms, and doesn't fall below that until 6000 rpms.

In the rpm range you mentioned, the 3 is nearly 100 ft lbs higher than the Civics peak torque the whole time.

How is that considerably less?

Edited October 14, 2006 by CaddyXLR-V

[LTB51]

The 3 hits the Civics peak torque number at around 2200rpms, and doesn't fall below that until 6000 rpms.

In the rpm range you mentioned, the 3 is nearly 100 ft lbs higher than the Civics peak torque the whole time.

How is that considerably less?

204818[/snapback]

I think he meant when the 3 is at low or high RPMs it makes significantly less torque than when it is in the mid RPMs. I don't think he was comparing it to the absolute torque numbers of the Civic.

This is interesting though. It might explain why the RDX is so much faster than the CX7 in spite of the similar peak numbers.

The other thing that struck me was just how smooth the civic line is compared to the other cars. You always hear how Honda engines are "smooth"... interesting to actually see it shown quantitatively.

[siegen]

This is interesting though.  It might explain why the RDX is so much faster than the CX7 in spite of the similar peak numbers.

204991[/snapback]

The RDX is a little better. It doesn't drop off as much in the high end. the TOV did a dyno test on it, and posted the chart (you can see it here). I overlaid its torque curve onto the Mazda dyno below (light green line is RDX TQ). Keep in mind the RDX's power was being fed through an automatic while the Mazdaspeed through a manual, so the numbers will be lower on the RDX. The dark green line should be approximately what the RDX would do with a manual transmission (since they both have the same peak TQ number at the crank, the losses would hopefully be about the same).

Looking at the torque curve you can see it doesn't drop off as much. Also, the reason it looks like the power comes on so late is because I don't think they went WOT until 2.5k to 3.0k rpms where-as the testers doing the Madza dyno stomped on it much sooner. I have a feeling the RDX has better low end TQ as well, since Acura focused a lot on that and the i-vtec would help optimize both ends of the rev range.

[Northstar]

The RDX is a little better. It doesn't drop off as much in the high end. the TOV did a dyno test on it, and posted the chart (you can see it here). I overlaid its torque curve onto the Mazda dyno below (light green line is RDX TQ). Keep in mind the RDX's power was being fed through an automatic while the Mazdaspeed through a manual, so the numbers will be lower on the RDX. The dark green line should be approximately what the RDX would do with a manual transmission (since they both have the same peak TQ number at the crank, the losses would hopefully be about the same).

Looking at the torque curve you can see it doesn't drop off as much. Also, the reason it looks like the power comes on so late is because I don't think they went WOT until 2.5k to 3.0k rpms where-as the testers doing the Madza dyno stomped on it much sooner. I have a feeling the RDX has better low end TQ as well, since Acura focused a lot on that and the i-vtec would help optimize both ends of the rev range.

204998[/snapback]

How does a manual transmission gain 25HP? Automatics typically lose 15-20% vs. crank while manuals typically lose 10-15% vs. crank (usually about a 5% difference depending on the model).

In regards to the test not being at WOT: Why does it matter? Doesn't the car make the same HP at 2500 RPM whether it's at WOT or whether it's just normal acceleration?

[razoredge]

Regardless of the this and thats, Honda did a great job getting that flat of a torque curve. It is a NA engine.........did anyone read.......even the author said you cant touch forced induction for its torque. While Im an advocate for low RPM torque over highrpm HP that we rarely use on the street, the extreme RPM and HP of that Honda must be extremely stimulating when drivin in anger and most likely gets the job done. This is the clientel that Honda attracts with their Vtec. So I wouldnt beat it down too bad. How would the NA ecotec or VW stack up ?

That said its too bad they did not include the SC SS Cobalt in this. That would be good for us to visually see.

That said I can already see that "other car company" already seems to steal the show and recieve credit for the DI twin scroll Ecotec in the media.........great..........tic toc tic toc tic toc...... Pontiac

Finally I loved this one

the Civic Si's drive-by-wire throttle is so slow to respond that you can literally press the throttle to the floor and release it without any response.

Something the 3900 also does but yet is denied by other owners.....just me again flying around in the twilight zone...........

Great job VW !

[regfootball]

And, yay, GTI wins for being the most powerful one with a linear delivery.

All reports I've read indicate that the Mazda Mazdaspeed Mazda3 (or is it Mazda Mazda3 Mazdaspeed?) has too much power for its own good.

204655[/snapback]

so lay off the throttle a bit.

[regfootball]

You really are one-track minded aren't you?

The Mazda3 makes big peak TQ and HP numbers, but has a poor powerband. It will be fast in a straight line, but the GTI would probably beat it around the track. Where the 3 keeps falling out of its powerband, the GTI will pull strong. The Civic Si has the nicest looking powerband and makes 85% of its peak TQ from 2k to 8k rpms, if it only had .2L or .4L more displacement...

Also remember the Civic Si weighs 250-400 lbs less than these other two. The Ariel Atom uses an almost identical engine out of the Civic Type R and it isn't slow by any means.

204657[/snapback]

yeah of course the civic makes 85% pk tq, it only makes what, 130 max? I can generate that much torque myself stirring a pot of spaghetti sauce.

yeah the civic weighs less, its a less useful car. the mazda3 spanks the civic so bad its not even funny. to suggest the civic's engine is the 8th wonder in the ariel atom is like me saying a corvette engine in a cobalt is relevant.

Is honda kool aid on tap at the fountain outlet at the 7-11?

[loki]

In regards to the test not being at WOT: Why does it matter? Doesn't the car make the same HP at 2500 RPM whether it's at WOT or whether it's just normal acceleration?

205002[/snapback]

i think it has to do with air/ fuel and if it's calibrated right or not...if your putting in tons more gas than should be in the combustion chamber it won't acceralte as well as if its close to WOT v. just WOT... wasting gas and therefor energy if all of it can't be combusted well.

make sense?

i only floor it if i want to screech my tires... other wise a progress way to push the throttle should be better for 0-60 times... i would guess it also can throw off HP numbers if less fuel could produce more power lower in the rpms.. say <3000.

[siegen]

How does a manual transmission gain 25HP? Automatics typically lose 15-20% vs. crank while manuals typically lose 10-15% vs. crank (usually about a 5% difference depending on the model).

205002[/snapback]

25hp may be a little much, but I wouldn't be surprised if it is close. The torque converter robs quite a bit of power.

I think the bigger thing we're missing is that the Mazdaspeed 3 engine is rated to 263hp / 280tq at the crank by Mazda, yet this test shows 216hp / 245tq at the wheels. A bit overrated there Mazda?? :AH-HA_wink:

I wouldn't be surprised if the CX-7 engine is a bit overrated as well, which may also be why it is slower than the RDX.

So not only does the Mazda have a cruddy tq curve, but it is overrated as well. For comparison, the Civic Si is rated to 197hp / 139tq by Honda, and made 180hp / 134tq at the wheels.

I'm not trying to say the Civic Si is a faster car than the Mazdaspeed 3. I'm just ragging on the Mazda. Wasn't the RX8 also overrated quite a lot?

yeah the civic weighs less, its a less useful car.

205055[/snapback]

That must mean the Corvette is a less useful car than the 350z, since it weighs less. Right? :AH-HA_wink:

[Northstar]

I think the bigger thing we're missing is that the Mazdaspeed 3 engine is rated to 263hp / 280tq at the crank by Mazda, yet this test shows 216hp / 245tq at the wheels. A bit overrated there Mazda??  :AH-HA_wink:

205149[/snapback]

216/245 at the wheels is a 18% drop and 12% drop respectively, I wouldn't call that overrated. Isn't it SAE certified anyways?

Yes the RX-8 was overrated a ton.

[siegen]

216/245 at the wheels is a 18% drop and 12% drop respectively, I wouldn't call that overrated. Isn't it SAE certified anyways?

Yes the RX-8 was overrated a ton.

205163[/snapback]

That is a pretty hefty drop. Compare it to the GTI which only lost 11% hp and 7% tq and the Si which only lost 9% hp and 4% tq.

Also compare it to the RDX dyno I posted. They ran the RDX on a 2 wheel roller dyno just like the one in the Automag test. Not quite sure about elevation or humidity though. The RDX engine is rated at 240/260 and did a 211/227 through an automatic transmission. The Mazda is rated to 263/280 and did a 216/245 through a manual transmission. Somethings not right here

[BrewSwillis]

[Cory Wolfe]

Ouch... my eyes. Please, someone remove that eye sore from the above post.

[Drew Dowdell]

That is a pretty hefty drop. Compare it to the GTI which only lost 11% hp and 7% tq and the Si which only lost 9% hp and 4% tq.

The Mazda is rated to 263/280 and did a 216/245 through a manual transmission. Somethings not right here 

205175[/snapback]

Naturally, different transmissions sap different amounts of power. I couldn't seem to find it in the article, but doesn't the GTI have a DSG transmission?

[csaba1218]

Naturally, different transmissions sap different amounts of power. I couldn't seem to find it in the article, but doesn't the GTI have a DSG transmission?

205424[/snapback]

yes it does have the dsg optional and it is a fantastic tranny i have the pleasure of driving one once in a while, and also the 3 and Si cant even come close to the GTI's refinement in the GTI you feel like you are driving a racecar that was designed to haul ass, the others feel like a souped up shi*box and the si is just a joke with that engine you have to rev it to ten million rpm's for it to even move.

GTI wins among these three no contest.

[Drew Dowdell]

I think the Si is proof that people focus too much on horsepower and generally ignore torque. Sure the Si has a great horsepower to displacement ratio, but so does my weedwacker. Unfortunately for my neighbors, I have to rev the hell out of my weedwacker to get any use out of it.

Edited October 16, 2006 by Oldsmoboi

[regfootball]

wasn't that torque figure on the SI a typo? Shouldn't it say 234? otherwise its like more than 100 lbft behind the Mazda 3.

[Drew Dowdell]

wasn't that torque figure on the SI a typo?  Shouldn't it say 234?  otherwise its like more than 100 lbft behind the Mazda 3.

205743[/snapback]

Civic Si = 139ft/lbs. @ 6100

MazdaSpeed 3 = 280ft/lbs. @ 3000 RPM

Volkswagen GTI = 207ft/lbs. @ 1800 RPM

Interesting comparisons

3.8 litre Regal GS = 280ft/lbs. @ 3600 RPM

3.6 litre Cadillac CTS = 252ft/lbs. @ 3100 RPM

2.5 litre Subaru WRX = 235ft/lbs. @ 3600 RPM

6000+ RPM to get to peak torque? That's the reason you have to drive the snot out of the Si to get anywhere while all the others can turn a more leisurely RPM and still feel fast.

Edited October 17, 2006 by Oldsmoboi

[regfootball]

Civic Si = 139ft/lbs. @ 6100

MazdaSpeed 3 = 280ft/lbs. @ 3000 RPM

Volkswagen GTI = 207ft/lbs. @ 1800 RPM

Interesting comparisons

3.8 litre Regal GS = 280ft/lbs. @ 3600 RPM

3.6 litre Cadillac CTS = 252ft/lbs. @ 3100 RPM

2.5 litre Subaru WRX = 235ft/lbs. @ 3600 RPM

6000+ RPM to get to peak torque?  That's the reason you have to drive the snot out of the Si to get anywhere while all the others can turn a more leisurely RPM and still feel fast.

205791[/snapback]

running at 6000 rpm all the time will give you horsecrap gas mileage too.

Edited October 17, 2006 by regfootball

[siegen]

Civic Si = 139ft/lbs. @ 6100

MazdaSpeed 3 = 280ft/lbs. @ 3000 RPM

Volkswagen GTI = 207ft/lbs. @ 1800 RPM

Interesting comparisons

3.8 litre Regal GS = 280ft/lbs. @ 3600 RPM

3.6 litre Cadillac CTS = 252ft/lbs. @ 3100 RPM

2.5 litre Subaru WRX = 235ft/lbs. @ 3600 RPM

6000+ RPM to get to peak torque?  That's the reason you have to drive the snot out of the Si to get anywhere while all the others can turn a more leisurely RPM and still feel fast.

205791[/snapback]

All of the 4 cylinders you posted there are turbocharged. The Si does have to be revved to go fast, which is no secret. For some people that is a problem, and there's nothing we can do for them. :AH-HA_wink:

running at 6000 rpm all the time will give you horsecrap gas mileage too.

205838[/snapback]

The mileage depends greatly on throttle position and load, and not so much on RPM's. How you drive effects mileage a lot more than any other factor. Driving the Civic Si and shifting at 2500rpms or at 5000rpms will make little difference in your average fuel economy. Driving the Civic Si at WOT or part throttle will make all the difference.

Here's a nifty little chart courtesy of the guys at Team Integra, where we don't just guess at things (hint). It is the stock fuel map out of the ECU for the Integra Type R. You can see the rpm axis and how little it effects fuel until you get to the high load area.

With a turbocharged car, whenever you are in boost, you are using considerably more fuel to compensate. This can happen at part throttle and even low rpms, depending on the turbo and tuning.

The main reason for poor fuel economy with a 4 cyl is actually do to giving it too much gas at too low rpms, or shifting too early. You are increasing both load and throttle (more fuel) without acheiving as much work (miles traveled).

[Drew Dowdell]

All of the 4 cylinders you posted there are turbocharged. The Si does have to be revved to go fast, which is no secret. For some people that is a problem, and there's nothing we can do for them. :AH-HA_wink:

205851[/snapback]

Get them a car with usable torque?

Edited October 17, 2006 by Oldsmoboi

[regfootball]

The main reason for poor fuel economy with a 4 cyl is actually do to giving it too much gas at too low rpms, or shifting too early. You are increasing both load and throttle (more fuel) without acheiving as much work (miles traveled).

205851[/snapback]

proof that car has no fricking power if you have to do that. give the car usable power. like an ecotec quipped car.

[siegen]

proof that car has no fricking power if you have to do that.  give the car usable power.  like an ecotec quipped car.

206500[/snapback]

How do you define usable power? If a car doesn't have a lot of get-up below 1300rpms or so, does it not have any usable power? If a car can't roast the tires off idle, does it not have any usable power? Would an ecotec 4cyl not also choke if you gave it a lot of gas below 1300rpms? Here's the solution...... are you ready?...... shift into the correct gear. It's that easy.

I regularly drive two vehicles at opposite ends of this spectrum. A '99 Integra (daily driver) and a '04 Sierra (work horse). The Sierra rarely gets above 1500rpms, and drives just fine. If I need to go fast, I give it some gas, it shifts down to around 2000-2300rpms, and I'm gone. In the Integra, I normally shift between 2500-3000rpms, and never let the rpm's drop below 1500rpms. If I want to go really fast, I just make sure I shift at a higher rpm. If I'm at 1600-1800rpms cruising and need to accelerate quickly, with just a flick of the wrist I'm back at about 3000rpms and have no trouble accelerating. It takes a different driving style, but once you're used to it, you realize there is nothing wrong with it, and it is more fun at the same time.

[Cory Wolfe]

What Siegen said. Reg is just Reg.

[regfootball]

What Siegen said. Reg is just Reg.

206551[/snapback]

bv, keep quiet, can you even drive a stick?

[Drew Dowdell]

bv, keep quiet, can you even drive a stick?

206714[/snapback]

yes, but he can't drive a manual transmission car.

[Cory Wolfe]

bv, keep quiet, can you even drive a stick?

206714[/snapback]

Yes I can. Thanks for asking.