MI-RDX

Agreed, it's torque that gets you going and HP that keeps you going. HP without torque is as useless as......

Joking aside it's torque that's needed to get an object moving (or to accelerate it). That's why more torque at low RPMs will always make for a quicker car off the line - all else being equal. In a 0-60 timing it's not how fast you go but how quick you get there and that means torque and making maximum use of it. In the C&D testing they were not utilizing the engine capabilities as well as they could have. Shifting closer to the 4500-5000 rpm range and using more of the 10 gears I'm sure would have resulted in a quicker 0-60.

Said another way if you put a 700 HP engine in the RDX but limited the transmission to just 10th gear it would be fast as hell once it got going, but it would take a long time to get there because of limited torque utilization.

RDX10

So you're effectively at sea level. I'm really starting to wonder if those initial test vehicles were played with. Hmmm..

Oh I know that, but I was thinking Bionicman might be living in some really high place, but that still wouldn't explain how the NA V6 2017 still felt quicker than the 2019 with the 2.0T. So yeah hmmm makes you think.

TacoBello

TacoBello

RDX10

Yes the NA V6 would be faster at his altitude than ours (btw I always get surprised when I realize how high we actually live lol). But the 2.0T would also be faster (albeit marginally). So in an apples to apples comparison, it's still strange that the 2.0T is slower than the V6 at his altitude is what I'm saying.

My 1G had a 6.3s 0-60 across numerous testing. The 2G had 6.1s, so I'm surprised that this 3G with a better transmission and more torquey engine would be slower than the 1G putting minimum. Oh well, a nice hondata tune would wake it up immensely.

TacoBello

TacoBello

RDX10

I think Ford limits power in the first 2 gears to protect the transmission. I've driven a few turbo fords so far and there is a noticeable reduction of power in the first 2 gears which is a shame. Why give us twin turbos only to limit them?

I'm also a huge fan of Hondata, but honestly this time around I'm not so certain I'd do it myself. There were some official papers citing a max torque rating for the 10AT and I'm not sure it would appreciate more boost. However on the flip side, the number stated as being the max is actually lower than the RDX'S number by 10 lb/ft iirc, so I think that info may have been false or something.

securityguy

A reputable tuner, like Hondata, will not release a tune that exceeds the capacity of the tranny or compromise it's longevity.

Bionicman

As someone with quite a bit of tuning experience on turbocharged vehicles with auto trannies, I can assure you that any significant bump in torque will reduce the longevity of the transmission. As I said in my original post, the 10AT struggles to command just the factory power at times, it's not going to put up with a lot of additional torque. Honda initially rated the new 10AT that worked its way into the RDX at 275lb-ft max, and it already exceeds that from the factory. (Acura is probably banking on RDX owners not being the kinda bunch to whoop on it constantly)

The Hondata Stg2 tune for the 2.0T Accord w/10AT provides a bump of 45hp and 40lb-ft. Compared to the tune for the 6MT, it's pretty obvious that Hondata is afraid of throwing a legitimate Stg2 tune at the 10AT, and for good reason. If I were a '19 RDX owner considering a tune, I'd get on the Accord forums and keep a close eye on how the tuned 10AT cars are holding up before making the plunge.

Wander

More likely there are changes in the 10AT for 2019 RDX to accommodate the additional torque. Honda/Acura isn't the kind of car company to sell time bombs to their customers. ( We have Dodge for that... hence the term "dodgy" ).

In a recent interview with the chief engineer for RDX, he was specifically asked about whether the 10AT was identical to the version in the Odyssey, and he commented that there are differences. The exact quote: "we've changed the top end of this transmission, to meet our performance targets, and we've adapted it for 4WD". ( around 35:00 in the posted clip )

https://acurazine.com/forums/third-g...toline-972981/

Bionicman

I guess your memory doesn't go back as far as the Honda/Acura transmission disaster from the early 2000's when they ignored widespread transmission failures for 5 years before finally recalled over 1 million vehicles in 2004.

RDX10

This is exactly what I was thinking about. I don't have faith in Acura when it comes to new transmissions, especially not something as complex as a 10AT. I will have to wait and watch the accord forums for people who boosted their cars with the 10AT/2.0T to see if they last.

I do remember reading about that 275 lb/ft limit and I'm wondering if they really did make changes, how much changes exactly? That 275 lb/ft limit is only about 5 more than the Accord makes iirc. So if they feel ok with a just adequate transmission in the Accord, why wouldn't they be ok with that in the RDX too?

TacoBello

Burger Steak & Eggs

Tuners can increase the torque handling capacity of an auto trans to some degree. Increasing the line pressure for example.....which should be software controllable.....increases the clamping force of the frictions. Add an outboard ATF cooler and you can gain a fair increase in capacity without hardware changes. All within reason of course.

MI-RDX

Bionicman

That's only if the TCM can be cracked by somebody. I don't believe it's been done yet on the 10AT, even for the Accord. For a traditional AT the remedies are usually a valve body upgrade, torque converter upgrade, ATF cooler if you're tracking or towing, and as you said, a TCM flash to increase line pressure. That being said, none of these remedies are available for the 10AT. I think if people start beating on these transmissions with a tuned up 2.0T, you're going to see grenaded planetary gears.

geals10

I'm confused about the new 2019 RDX. Car and Driver (https://www.caranddriver.com/acura/rdx) lists the new turbo 2019 Advance model at 6.2 (0-60) and the A-spec at 6.6.

acuraada

Bionicman

6.2 seconds was their original estimate before the car was ever released based on power to weight ratio, etc before they got a chance to do instrumented tests, that information is outdated. 6.6 seconds was what they got in their actual instrumented test.

Wander

IIRC, it was 87°F on test day, from their log sheet. I wonder if they turned off the A/C.

I also wonder if they were burning ethanol-free premium gasoline or whatever the corn-fed "summer blend" may have been. My Acuras are noticeably peppier running ethanol-free premium, no instruments required.

Bionicman

This is a professional outfit with decades of experience, I'm sure the A/C was off. Running ethanol-free premium for the test would also be foolish, as that's available in very few areas for consumers. And even where it is available, people aren't putting it in their freakin RDX's, as it's over a dollar more per gallon than standard 10% ethanol. There's a race fuel station not far from where I live that offers 91 and 87 ethanol-free, and I don't even fill up my G37xS there. I only pony up for ethanol-free fuel for my tractor and power equipment.

TacoBello

Bionicman

If it's a 3rd Gen or newer it's designed to run on E10, but if ethanol-free makes you feel warm and fuzzy inside, spend the extra money. You'll prolly get slightly better mileage with it.

Wander

More importantly for the current discussion, slightly better performance. Gasoline has a higher energy content than an equivalent volume of ethanol.

BTW, ethanol-free is the ONLY 91 octane fuel available at many of the gas stations in my area, and it's $0.70 more per gallon than 10% ethanol 87 octane.

Also "summer blend" gasolines have a slightly different composition than "winter blend", largely to reduce undesirable ( and unproductive ) venting of hydrocarbons into the atmosphere. But apparently I had it backwards and summer blend has more energy content than winter blend. These effects are typically small, but with these highly tuned computer controlled engines, who knows what is going to influence their mood on a particular day.

https://newsroom.aaa.com/2013/06/wha...lend-gasoline/

I can probably get along just fine with the performance of my 2019 RDX whether it makes it to 60 mph from a standing stop in 6.6 seconds, 6.2 seconds, or whatever. It's peppy enough. I'm just a bit puzzled by the spread of "test results".

Bionicman

You missed my point. 99.99% of RDX owners will put E10 pump gas in their RDX, not ethanol-free premium, VP100, or anything else. The most appropriate fuel for their instrumented test would be standard E10 91 or 93 octane, as that's what the average driver will fill it up with.

iforyou

iTrader: (1)

The 10AT for the Odyssey is rated at 275lbft capacity by Honda. But the 10AT while similar, is different on the RDX. Also, I'm not sure if Honda just made up that 275lbft capacity for the Odyssey, in a sense to prevent competitors from knowing what tranny they will use for other cars. For instance, when they said the 10AT in the Odyssey is good for 275lbft, logically, one would think it wouldn't be found in a 2.0T engine since that engine is already make that much torque. But in the end, both the Accord 2.0T and RDX 2.0T have the 10AT. May be the actual capacity is 280lbft, or 300lbft. or 320lbft. or 350....only Honda knows the actual rating. Or perhaps, the design of the 10AT is flexible enough that the torque capacity can be adjusted with different parts based on application.

I personally had a 2G TL-S which had the 5AT issue by 200000km. Costed me quite a bit of money to get it fixed by swapping a 07 Accord V6 5AT into it. I think Honda fixed the newer 5AT, and the 6AT has been mostly reliable (heard about some issues with them but nowhere near as bad as the early 5AT). I can understand why one would feel pessimistic about the 10AT reliability based on the early 5AT, but for me, the newer 6AT has been rock solid enough that I'm not too worried about the new 10AT. I am also leasing my RDX so if it does have issues...not gonna be my problem hahaha other than a bit of a hassle if any problem were to occur during my lease period.

Wander

I missed nothing. I tend to be more careful with statistics, but I guess it's trendy to make up whatever "facts" are favorable.

As I have noted, there is regional variation in what types of fuels are available, and I have no idea what an "average driver" is supposed to be. By any reasonable definition the "average driver" probably fills up with E10 "regular" 87 octane, and doesn't drive an RDX. I suspect C&D filled up with whatever was available in their area, but unless I missed something they didn't specify. Nor does anyone else who has posted 0-60 times.

Maybe the difference is "down in the noise". Maybe more significant is the ambient temperature on test day. 87°F isn't really a year-round "average" for anywhere I want to live. YMMV.

Mostly, I'm pointing out that unless comparable vehicles are compared back-to-back under identical conditions, it's difficult to make meaningful conclusions on relative performance. ( Which isn't to say I haven't wasted far too much time poring over published charts of 0-60 times ). I haven't yet challenged my wife to a drag race in her 2014 MDX. Mostly because she might call my bluff!