[Euro] Hondata Update

[7ypeR]

And as for revving the crap to get it moving - I could also say I felt the same thing when driving a DC5R. Most Hondas need revs on board before the pace arrives.

Maybe it was just me then. As I said "no offending intended" or something along those lines . Look perhaps I may have over exagerated. The car (euro) just doesn't drive like 2.4L motor. There's just no torque there. I'm sure if you kept the car at boiling point, it would run with dc2's & dc5's. But what i'm talking about is the effort to bring it to vtec. The euro owners would know what i'm talking about.

P.S Why would you buy a rex, it's a subaru at the end of the day

[aaronng]

Maybe it was just me then. As I said "no offending intended" or something along those lines . Look perhaps I may have over exagerated. The car (euro) just doesn't drive like 2.4L motor. There's just no torque there. I'm sure if you kept the car at boiling point, it would run with dc2's & dc5's. But what i'm talking about is the effort to bring it to vtec. The euro owners would know what i'm talking about.

P.S Why would you buy a rex, it's a subaru at the end of the day

On contrary, the stock Euro has less torque when in VTEC than when at a lower RPM. Try 2nd gear. The Euro pulls harder at 4000-5000rpm than at over 6000rpm.

You have to remember, eventhough it is a 2.4L engine, it's still an inline 4. If you want more torque, it needs to be a 2.4L V6 or I6.

[sodaz]

The car (euro) just doesn't drive like 2.4L motor. There's just no torque there. I'm sure if you kept the car at boiling point, it would run with dc2's & dc5's.

The Australian DC5 engine is not really any stronger than the Euro's imo. It makes 147kw (only 7kw more) at a high 7400rpm and makes a lot less torque (only 192nm compared to 223nm). It needs more revs on board to get it going since it doesn't have the capacity. The only reason it's quicker than the Euro is because it's much lighter with shorter gearing.

[Merlin086]

On contrary, the stock Euro has less torque when in VTEC than when at a lower RPM. Try 2nd gear. The Euro pulls harder at 4000-5000rpm than at over 6000rpm.

You have to remember, eventhough it is a 2.4L engine, it's still an inline 4. If you want more torque, it needs to be a 2.4L V6 or I6.

I think you need to do some more reading aaronng and not continue to state your opinion as fact.

Try starting here..

http://en.wikipedia.org/wiki/Stroke_ratio

Torque output is primarily based on bore/stroke ratio in a NA engine.

Search is your friend......

[yfin]

so with the mild flash how much extra KW at the wheel would you get compared to stock?

Looking at the dyno the mild flash is more about gains below peak power and torque. The peak difference is not all that much.

Stock on hub dyno is around 125kw - with mild flash and intake it is around 132kw.

So that takes it to around 148kw at the engine (assuming stock is 140kw).

But I think the stock car is underquoted by Honda from the factory and probably is closer to 147kw than it is to 140kw. Or it could be the drivetrain is just very efficient as more powerful 147kw rated cars read similar to the Euro on the same dyno.

[ENVSSS]

I think you need to do some more reading aaronng and not continue to state your opinion as fact.

Try starting here..

http://en.wikipedia.org/wiki/Stroke_ratio

Torque output is primarily based on bore/stroke ratio in a NA engine.

Search is your friend......

I can agree with both Merlin086 and yfin in this discussion. I also own a SSS Nissan Bluebird with an I4 2.4Ltr, 112kw/210nm. It is a little undersquare compared to the Euro and I can definitely notice more torque than the Euro below 3000rpm but above that point the Euro is better, despite being a little heavier.

[aaronng]

I think you need to do some more reading aaronng and not continue to state your opinion as fact.

Try starting here..

http://en.wikipedia.org/wiki/Stroke_ratio

Torque output is primarily based on bore/stroke ratio in a NA engine.

Search is your friend......

With a 6 cylinder engine, you get more combustion cycles per rotation of the crankshaft, thus giving you the feeling that it is not struggling to build up torque and revs. Haven't you noticed that even an older 2.5L V6 or inline-6 revs up very willingly from idle when compared to the Euro's modern engine?

Bore and stroke defines the optimum range of RPM efficiency. Oversquare engines stay efficient at high RPM while undersquare ones are less efficient since they have a longer stroke but have better response at low to mid RPM.

[Merlin086]

With a 6 cylinder engine, you get more combustion cycles per rotation of the crankshaft, thus giving you the feeling that it is not struggling to build up torque and revs. Haven't you noticed that even an older 2.5L V6 or inline-6 revs up very willingly from idle when compared to the Euro's modern engine?

Bore and stroke defines the optimum range of RPM efficiency. Oversquare engines stay efficient at high RPM while undersquare ones are less efficient since they have a longer stroke but have better response at low to mid RPM.

Typical aaronng, there you go talking "feelings", I am talking FACT!!!


This article will explain it better than I can, especially as it is discussing the K series engines.

http://books.google.com/books?id=0rY...rk0xMvmn2gOYW0

[aaronng]

Typical aaronng, there you go talking "feelings", I am talking FACT!!!


This article will explain it better than I can, especially as it is discussing the K series engines.

http://books.google.com/books?id=0rY...rk0xMvmn2gOYW0

And here you are quoting a wiki article that has no references. Anyone can write a wiki article. I know I have. I don't trust wiki articles except for light reading unless they are referenced.

Remember, pistons and rods have inertia too. The higher the number of cylinders you have for the same capacity, the lighter the pistons and rods. The lighter the pistons and rods, the lower the inertia and you require less energy to increase their velocity (and RPM).

If you are so adamant that the k24a being undersquare is the reason why it has more torque at mid-RPM, then tell me why does the b18c, which is also undersquare has most of its torque at the upper RPM range? Peak torque can be shifted upwards around using cams of longer duration and lift. It's not only dictated by bore/stroke ratio. Of course, in a k24a, it is also limited by poor filling efficiency above 5000rpm.

[yfin]

No, yfin's method of calculation is correct. You have to compare before and after readings on the same Jtune dyno to get the percentage gain, and then apply that percentage to the manufacturer quoted flywheel kW. So it's 177kW.

Sorry, but I can't do that as a comparison unless I put all the other cars on the same dyno...der...

Or would you like me to put them all down the 400m for u..............

Merlin - not sure what is unclear about what Aaron or I have said.

If on the same dyno the Jtune stuff shows 26% gain at hubs (peak)- that percentage increase can be used to work out the gain from Honda's figure of 140kw at the engine. 140 * 1.26 = 177kw

The thing is the peak power for the extreme package is not its biggest selling point. It is the gains lower in the rev range that are most impressive.

[aaronng]

BTW Merlin, did you read that external link in that Wiki article you posted? It says that you can't predict how revvy the engine is based solely on the bore/stroke ratio. Here is the link so you don't have to go through that article again: http://g-speed.com/pbh/bore-vs-stroke.html

[jooboo]

Quote from JTune website

“Dyno Results – The Extreme package provides maximum improvement for both power & torque throughout the rev ranges combined with a vtec point of 3148. Gains of over 45% are seen in both power & torque at 6000rpm. Peak power is generated by 6000 which is maintained all the way to Redline at 7200rpm”

In fact when you do the math’s 105.7kw vs 158.3ks @ 6000rpm is almost a 50% increase in power mid range, now that’s worth talking about !!!!!!!

Me and my brother were at the APC open day last week for JTune and went for a drive with Merlin and believe me the mid range performance is mind blowing, who cares about peak performance mid range is where we all drive, although still a 26% increase at peak power is still nothing to sneeze at.

I think Merlin summarized it nicely it exceeded his expectations and it exceeded mine for sure.