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4.25 manual ex coupe 6th gen

???? manual ex coupe 7th gen

 
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Now if we had each gear, we could find gear multiplication and find how much power is being put the tires, but I really don't think this discusion is worth it.

 
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6th gen dyno AEM
http://www.aempower.com/pdf/dyno/21-...20EX%20CAS.pdf

7th gen dyno AEM
http://www.aempower.com/pdf/dyno/21-...20EX%20CAS.pdf

Stock NUMBERS
=============

6th gen 104.4 whp
93.2 ft-lb torque

7th gen 111.0 whp
104.8 ft lb torque

 
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final drive for 7th gen EX is 4.41

 
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Let's put the gear thing aside first, it really don't make much difference if one is 4.2 and another is 4.3.

It looks like 6th gen are made for high rpm horsepower while 7th gen are optimized for mid range. What it means is that, given horsepower as a function of rpm, using finite method, sum up every point and 7th gen's number will be considerably greater than of 6th gen, means that 7th gen IS faster than 6th gen(power distribution). If the weight of 7th gen is the same as the 6th gen, it will be faster than an Si.

 
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7th gen EX is 20 pounds heavier than 6th gen EX. Its not much.

But the current SI is quite a bit heavier.

 
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are you saying a 7th gen ex is faster than the 6th gen Si? cuz that would be way off.

 
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7th gen EX is 100 lbs heavier than 6th gen EX. That's why Honda puts in a slightly bigger engine to get more torque to pull the car.

All the weight comes from the body not the engine. The engine and transmission actually weigh much less than 6thgen.

Putting D17 into 6th will not win 6th gen Si, but surely can match with 7th gen Si(power/weight ratio).

 
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I guess the candian si(american ex) is lighter since our side air bags are optional. I'm guessing the same is true for American early 7thgens. I got my weight from honda.ca and its the same weight on my registration

 
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why is this thread still going? hasnt this thread or at least this topic been in discussion forever?

 
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7thgen EX > 6thgen EX

 
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You are trying to say you have to intergrate the area under the curve. Nice try, but why use a finite methode on a continous function? FEM (finite elemntal method) is better applied to to solid sheer stress coumpounds and breaking points of solids (i.e. when a gear tooth will break). It is really much simpler, just intergrate the area under the curve, you can easly form an equation to fit the line of the curve, given you got the graph in electornic format, excell will do a simply regression for the equation in less than a seocnd. If you don't have an electronic form of the dyno, then use the paper with a finite block method will get about the same, but with less accuratcy. Then just intergrate of the the RPM range of each specific gear, which means you will have to record all your shift points and how much the RPMs drop on each shift, not hard. Keep in iond your dynos are normally done in 3rd gear, so that is the only gear you really become concerd with for this type of exercise. The hard part is now that you have the area under the curve, what are you going to do with it? This is known as power delivery, most experience people just look at a dyno and can tell if it is a drag queen car or has good power delivery.

Final point is that:
peaky curves = low perforamnce due to bad power delivery
a nice flat torque and horse power curve = good performance via better power deliviery.

You can go intergrate all that stuff or just take what I just mentioned as law. Unless you really want a specfic charteristics of the engone, reasons for differentiating that is low. In the case of a rocket or some aero space eningeering program, I'm gussing most engines are ran at more or less constant speeds, so such a dynamic annalysis of an engine is not needed.

 
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LOL, repost!!! in the same thread.... LOL Yes I agree.

 
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hahahahahaha

 
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It is very bad to have peeks and dips noticible in the dyno. However, torque graph will never become flat(or the car will not accelerate at all). Horswpower wise, good to get more midrange than high range(time issue). Say if my car has generally 10 hp higher than your car between 3000-5000 rpm, and your peak is at 115@6300, my peak is set at 110@5300, and we both have a very flat hp curve(as all d17a2 civics do), my car will still run faster than yours. Kind of.

 
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Yeah, in that later example with horsepower, that is when you may want to get the ruler out to measure the area, becasue in a case that close, it will be very dependant on how broad the peak is, but you get the idea. It will more so be a drivers race where I will have be strogling to keep my car in it's power ban while you have no worries of that.

 
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Which durve is smoother 6th gen ex or 7th gen ex?

 
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7th gen. Much smoother without any correction.

 
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yeah, much nicer. They are both posted all over.

 
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Everything was due to the long intake runner (optimized for mid range) and the extra-low VTEC engagement point. People wanted to put VTEC controllers in to make engagement point down to 3000 to compensate for the loss after 3000 and the jump at 4500 in older civics. We have that from the factory.

 
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This is off topic but with lighter rims and v rated tires, how does it affect our 0-60 and 1/4 mile times?

 
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Slower unless you go with ultra light 14" and ultra low traction tires. Rolling ressitance is I=mr^2 which means mass is NOT as important as the raidus. Radius goes with square. V rated tires always have better traction, and traction is actually friction, that will add to your acceleration resistance.

 
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Cool So grippier tires with actually slow me down, on the RSX Type S many people have had improvement in their 1/4 mile times with stickier tires.

So Kosei 14 x 6 inch rims (9.3 pounds) with which tires would make a significant diff over stock?

 
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For daily driving, I would not recommend a poor traction tire because it will be dangerous. Lightweight rim but sticky tire can be good combination. If you don't care speedometer readings, just go ahead to get a low profile tire. (The tire wall adds to the (I) equation also)

 
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So could you say acceleration could improve by as much as .2 seconds?

and 1/4 mile as well?

Is there a way to calucalte the results without actually going out buying everything and beeing dissapointed?

 
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0.2 seconds? Train yourself is a better way other than buying whatever.

 
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there is fine balance you need to consdier when buying tires.

1. Traction is only as much as you need. So buy putting sticky tires on your car, you can create more traction and friction. However this is far far out wieghed by the fact that you can now put more power down more power with out spinning your tires and luanch from a higher RPM. Put a low traction tire on, you will spin your tires, you go nowhere very fast. Put tires that are to sticky on your car you will loose some time to friction, but it will be fractional.

2. Remeber that if the tire is wider, it will have more traction too, and hence more friction, even if it is teh same tire, wider is better for traction.

So, more traction is good for the strip becasue you can put more power down and get better luanches, more power to the ground >> than the power lost to friction. However for dialy driven cars, traction like this and friction = big looses to MPG, so a skinny tire is desired. That's why Honda puts some what skinny tire on their cars from the factory, look at the S2000.

 
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The balance i talk about above is that you need to find a tire that is sticky enough to handle your car's power output, but not so sticky that you are loosing gobs of power to frictional looses.

 
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Good traction doesn't do much to FWD cars on strip. Period.

 
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LOL, I raced in snow tires then put on a set Toyo RA-1's and my time dropped by .7 seconds.

Come on, with out a high end simulation and tests to back up the theory you learn in class, it just that, theory, while your theories often do hold true, you leave out way to many other factors to be able to properly simulate or make assumputions. For instance, in physics they will tell you that you can stop faster with ABS than without, yet it is widely known that this is not true, given you are a perfect driver in perfect conditions.

To say that traction doesn't make a difference is just wrong. True many poeple put alot more sticky tire than they need. But how do you plan on putting down more power (i.e. torque) with out increasing you traction? I had an older civic that in street tires could smoke the tire through every gear all the through third gear and most of fourth. Now I put slicks on it, I can run through all but 1st without a problem.

So if traction doesn't make a difference, why do pro FWD racers use slicks? According to you they would run the same times on Honda OEM tires right?