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Discussion Starter · #1 ·
Hey all,

Not sure if this has been posted before...so, i do apologize if this is a repeat.

First thing, get yourself an MDX brochure AND a Honda Pilot brochure! Ok, next, look through the brochure to find the "HP/Torque graph". Now, compare the two graphs...you will see something odd!

Just FYI, it was assumed by many (including me) that the Pilot's engine and MDX's are the same, with slightly different tuning. It has the same displacement, compression ratios, and design. However, the biggest difference is that the Pilot's engine uses REGULAR fuel (similar to the new Odyssey's engine). MDX uses premium. On paper, MDX spec shows that the torque is 245 lbs from 3000-5000 RPM. With the Pilot, torque peaks at 4200 (i think).

However, if you look closely, the range from 3000-5000 is very similar in both graphs. Now, look at the torque BELOW 2000 RPM...do you notice anything?? Yes, the MDX torque drops off rather rapidly in comparison to the Pilot's...that is, at low RPM, the Pilot has significantly MORE torque than MDX! :confused:

Am i imagining things?? Do you guys see it too??? Is this a mistake by Honda printing people???

Strange....
 

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Yeah, it's hard to say if that's accurate or not, or which one is.
Reviews always seem to favor the MDX in acceleration maybe by 0.5 sec 0 to 60 but both vehicles weigh about the same if you add the Touring pkg. in the MDX.
It does seem odd there would be any engine differences at all.
And since the Pilot is newer maybe the 2003 MDXs will have the same engine as the Pilot and run on regular. But there are rumors it will have another 20hp or so in the MDX. If it runs on regular and still picks up more power, that would be good and probably enough to offset slightly less MPG. With less restrictive exhaust maybe no MPG difference. But if a larger displacement...oh, well.. of course this is all conjecture based on how things look right now.
I noticed reviews show the Pilot to have softer handling. Probably due to spring rates, as both have the same size stabilizer bars.
 

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DaleB said:
Yeah, it's hard to say if that's accurate or not, or which one is.
...
It does seem odd there would be any engine differences at all.
...
Not really too odd. It would be relatively easy to change the fuel injector curve through programming which would directly change the torque curve and the acceleration.

I don't know if Honda has done such a thing, but it would give a different feel to each vehicle, and might even make for a specific 'target driver'.

Similarly the shift points could be changed to help keep the MDX on the top of its torque curve, giving better acceleration, while the feel of the Pilot could be set for softer shifts with resulting (slightly) slower accel numbers.

I doubt they would change any 'hard parts' (intake manifold, cam shafts, valves, transmission /final drive gear, torque converter) but that is where the REALLY noticabel differance would come in -- anybody rememebr the performance heydays of Detroit when the DEALER could install special cams & intakes??
 

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My quess is the Pilot is running different primary cam profiles and timing which let it run on regular and build more torque down low. This would make the Pilot a better "around town vehical". Honda's marketing is quite amazing and I am not suprised that they would retune the Pilot from MDX specs. They know there customers very well and build a excellent product.
The Pilot is a family UV and the MDX is the Sport UV.
The Pilot should make you feel even better about your X.
 

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Discussion Starter · #5 ·
Hey all,

What you guys are saying is a possibility. However, i have NEVER seen this much of a difference in two very similar engines. Sure, Honda can retune it, but not this much. If you guys can see the two torque curves, you will see what i mean.

Another comparable example is the Lexus LX470's engine and the Sequoia's. LX470 has the 4.7 L V8 engine that uses premium fuel. The Sequoia has a VERY similar engine (called, i-Force) that uses REGULAR fuel. Power between the two is slightly different:

LX470: 230/320 (HP/Torque) Premium fuel
Sequoia: 240/315 (HP/Torque) Regular fuel

As you can see, this situation is quite similar to the Honda Pilot/MDX. However, the torque curve between the LX470 and Sequoia is identical from what i can see (5 lbs torque is too small to see on the Toyota brochure graph). This is something i would expect when i look at the Pilot/MDX brochure.

Thanks.
 

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Actually the lastest review (Pop.Mech. July 2002) shows the following for Pilot (EX) vs. MDX (touring).

MDX / Pilot

wt. 4420 4420

0-30 3.2 3.4

0-60 8.45 8.57


1/4 mi 16.26/85.5 16.37/85.26

Passing
60-70 6.17 6.22

Slalom
(seconds) 40.6 40.3

Lane
Change
(mph) 49.4 47.0

Noise
Level
idle (db) 46.6 49.0

60mph 72.0 74.5

Full
Throttle 79.3 79.7

Nothing here to support any significant differences, and the Pilot is to run on regular. Less noise and a quicker lane change in the MDX.
 

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I read a article long time ago about premium vs regular gas which discuss pros and cons about putting for a vehicle. These things aside, there is one specific point they mentioned. The article was published around 1999 and it stated that most modern engines that uses premium gas has knock sensor and will adjust engine timing when a regular fuel is used. The article gave one example engine but I forget which now. My 2000 Maxima recommend premium but will take regular. So I have been using mid-grade ever since. The sale man even told me that regular fuel is better on long trip for reason I don't remember now.

Now what does it mean for the MDX engine here. Well, I, for one, would believe that its engine is more advance than the 2000 Maxima engine and so I would also believe that it has the same system to allow it to take regular fuel (this has been confirmed in earlier posts regarding premium vs regular gasoline).

Given the same logic, I would also believe that the engine in Pilot would have the same system. Once you developed and built it, it is next to nothing for Honda to put it in Pilot. Unless Honda thinks that people will notice that Pilot has more power than it advertises and that MDX owner will freak about this. Who is going to be bother with this little difference and get a dyno test? Well, no one except some MDX owners here.

I think the two engines are pretty much the same with very small difference in pre-programmed timing setting. Although I can't say for sure that their timing will be identical when feeding premium fuel, I strongly believe that have the SAME timing and power/torque when feeding regular gas. If I am the one responsible for setting the right timing for both engines, would I set a different setting, knowing that whatever setting you set won't give any meaningful difference?

In the 70's (?), Cadillac under advertise a car's power rating by something like 30 HP so that they could claim improved power in the next year with the same engine! Many Japanese sport car sold in Japan has more than the mutually agreed maximum at 270 HP.

My point is: they (MDX & Pilot) are the same engines but Honda wants the MDX owners to think they get a more powerful engine.
 

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The Pilot's specs listed in these posts clearly show Honda has made tuning changes to the 3.5 beyond the differance made by regular fuel.. A minor drop in overall gearing would produce these changes and the Pilot's lower avg MPG supports this.
Time will show the differances and some, if desirable, may be applicable to the MDX.
 

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QUOTE
My point is: they (MDX & Pilot) are the same engines but Honda wants the MDX owners to think they get a more powerful engine.

I think that's a bit of a reach. In order to do that Honda Co. would have to plan that when the MDX comes out in 2001 it will run on premium. And when we come out with a 2003 Pilot in 2002 we will tell everyone it can run on regular.

Your description of the engine adjusting to the octane being used, is basically correct. However, one way it would adjust for lower octane fuel is to retard the ignition spark to prevent knocking. When it does that, the efficiency of the engine drops some, which means poor fuel mileage. It usually means less power but probably not enough of a difference to really feel through the 'seat of your pants'.
But the engine can be calibrated to run best on regular or premium. It is very likely the engineers found they could do that with the new generation Pilot with little sacrifice in mileage or performance. And by doing that found a way to sell the image of a more 'family' type vehicle, so it was also more agreeable with their marketing strategy.
 

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Here's my speculation:

I think the Pilot engine has some improvements over the current MDX's engine. Some of those improvements help it get good power from regular gas.

With regular gas, the Pilot's engine doesn't exceed the MDX's engine (running on premium). But the difference is quite slight.

With regular gas in the MDX, some MDX owners have reported definite losses of power (there was a thread a while ago with an owner complaining of insufficient passing power, but it turns out he was using regular, and the problems went away when he went to premium).

But if you put premium in the Pilot, its engine may well match or even (quite slightly again) outperform the MDX's.

Honda says for the Pilot to tow well, the owner should use premium gas for more torque.

I wonder if that Pilot torque curve in the Pilot brochure is based on the dyno'ed vehicle running with premium fuel. That would explain a possible difference. I wouldn't put it beyond a manufacturer to do that (making the torque curve look better by putting legal fuel beyond what is recommended for normal driving).
 

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vmquan:

I think we are saying the same thing with minor differences.
The proof is in the pudding and what MDX will have in 2003 and if it will run on regular.
If it doesn't run on regular, it better not get much less mpg or it might be a detractor.
They could always have an optional engine too. Similar to the TL with an S option.
We should know in a few more months.
Of course they should add about a $1000 of bolt on exhaust, intake, maybe a chip change, and offer it as an upgrade for older MDXs.
Now you know i'm dreaming. But if Toyota can get factory approved superchargers...then.............
 

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I don't think TRD will support RX 300 mods...

DaleB said:
I think we are saying the same thing with minor differences.
The proof is in the pudding and what MDX will have in 2003 and if it will run on regular.
If it doesn't run on regular, it better not get much less mpg or it might be a detractor.
They could always have an optional engine too. Similar to the TL with an S option.
We should know in a few more months.
Of course they should add about a $1000 of bolt on exhaust, intake, maybe a chip change, and offer it as an upgrade for older MDXs.
Now you know i'm dreaming. But if Toyota can get factory approved superchargers...then.............
Funny it is listed as fitting the Camry, but it only talks about trucks in the warranty -- http://www.trdsportparts.com/SuperCharger_javas/warranty_java.asp

Acura is a long way from bringing that kind of business in the stores, and I doubt that Lexus would ever do the same...:D
 
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