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'02 LX Canadian with auto trans with 363,000km on it.

I've driven '11 Kia K5(Optima), '06 BMW 535i and '06 Lexus IS250 until this car but this car especially, feels really weak on power.

I usually drive with only 1/4 of acc. applied but it seriously lacks power. I usually end up getting dirty looks while getting overtaken 5 seconds after green light from a stop.

I try to make my car shift at 2500 RPM by lifting a bit of acc. (which makes it shift around 20, 40, 60kph) but unless I do that, it goes almost to 3000RPM (which makes the car shift around 25, 50, 70kph but this feels really over-revved to me)
And cresting an uphill makes me have to open up to half pedal to barely do 50-60kph on 3rd gear.

Is this behavior normal for this kind of mileage on the car? I mean, it has less HP than the cars I've driven so far... but this is really a new experience for me.

 
Rep Power: 210

Here's the 7th gen LX (ball-less) engine specs:

D17A1

• Found in:
  • 2001–2005 Honda Civic DX/LX/VP
    • Displacement : 1,668 cc (101.8 cu in)
    • Bore and Stroke : 75 mm × 94.4 mm (2.95 in × 3.72 in)
    • Compression : 9.5:1
    • Power : 115 hp (85.8 kW, 117 ps) at 6100 rpm
    • Torque : 110 lb·ft (15.2 kg/m, 149 Nm) at 4500 rpm
    • RPM redline: 6750 rpm
    • Rev-limiter : 7200 rpm
    • Valvetrain : SOHC (4 valves per cylinder)
    • Fuel Control : OBD-2 MPF

So, yes it's going to seem slow compared to the other vehicles you posted and that's mostly due to the lack of torque . Even the Kia Optima has decent power: 192 to 274 hp depending on engine model (2.0L, 2.4L) comparatively. However, the Civic's curb weight is lighter than the other cars you posted. My mom has an '04 Civic VP (same engine as LX) and as with most older Civics it geared towards higher rpm shifts due to it's ball-less torque numbers. You simply cannot compare this engine to a BMW or Lexus 6 cylinder engine..the Civic is a no frills economy-box that is a third of the price when new compared to a new, same year Lexus or BMW.

 
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Now it makes sense, it does give more torque (of course) when I use around 3000RPM range.
I mean, don't get me wrong. I'm actually in love with Civics right now. I'm absolutely baffled how this car is still running strong (apart from lil' bit of shifting slips) after 360K kms of poorly maintained mileage. I'm sure I'll get a Gen 9 Civic next.

However, until that day comes, I'm with this girl. Is there anyway I could mod the car to give better low-end torque without making things too complicated?

 
Rep Power: 222

No there's really nothing you can do to improve the power besides an engine swap or a turbo. You can try doing 3 drain and fills on the trans see if that helps with shifting

 
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I'd be happy if I could just add 30-50 HP from current because the car should be really weak to handle the additional power from as it is now (I did overheat the heck out of this car 3 mo ago )

So, I found out from searching that Honda ATF Z1 is discontinued. What should I use for alternative?

 
Rep Power: 229

Hondas are high rpm, peak torque engines.

with the manual transmission vtec doesn't even engage until 3500rpm, peak power is at 6000rpm, red line fuel cut at 6800rpm.

So you should shift at 6000rpm, for the fastest 0-60.

....

Though with an auto it will shift for you, a lot lower.

best if you sell that car and buy a sports car, if you want to stick with honda the cars below are in the same price range as you current car.

(Obviously dont waist your money on an automatic)
-civic si 94-2005
-acura integra 94-2000
-acura rsx type s 02-06

Your looking for B16/B18 or k20/k24 engines.

 
Rep Power: 210

Not possible without an aftermarket turbo setup.

Overheating can lead to a breached headgasket. Any coolant loss in radiator combined with coolant gain in the reservoir? What caused the overheating?

Can use Honda's current ATF as it's backwards compatible. Can also use Valvoline Maxlife synthetic blend (not full synthetic), or Castrol MVI (multi-vehicle import) full-synthetic. I've used Lubegard Red additive in a 6th gen Civic without issue. It had a mild hard shifting issue but it turned out that was common with EX transmissions of that generation. The Lubegard didn't smooth out the mild hard shift but it didn't cause any issues with the transmission either and may have helped it run cooler as it claims to do??

Spoogegard Red : https://www.lubegard.com/products/red/

 
Rep Power: 222

You realize you're asking for a 50% power increase?
Again not possible without an engine swap or forced induction

These cars are delicate when it comes to the headgasket, you may want to read the sticky, if you start to experience those symptoms, verify that it's blown, and then replace it with a new oem one. If you catch it early you might not have to machine the head.

whatever the new Honda ATF is. Or the Valvoline or Total equivalent that meets the Honda spec

 
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So.. a bit of story time. Bought this off of a guy for CAD550. He did mentioned the radiator need constant refill with water since it loses fast. I took a bite to get this car as a first one for moving to Canada, bit of project car for commute beater. So, picking up the car and to drive home, I assumed the radiator was filled with water. It wasn't. The temp. gauge was reaching max when I noticed, and immediately parked to the shoulder of highway. Cooling off, and limping to nearest gas station for getting some random generic coolant. Filled it with no joy, car was overheating again.. but after it cooled down, I took a gamble(stupid one now that I think of, could've costed me my life) and drove back home. As soon as I parked, the engine died. Thank God. It took me 1hr 30min with THREE overheat to gauge's maximum. I'm actually surprised how the hell the engine is still running (for now)

After towing the car to a shop for inspections, they told me radiator was leaking bad, so swapped the radiator, ECT, thermostat... and timing belt too with valve cover gasket. now it runs quite good, not perfect but it'll do.
Had oil leak but it was from cam plug. No coolant loss, or color in exhaust.

Heard good things in the web for Valvoline. Might go for a 3 drain and fill with it.

Yeah, I just realized it.. sounds really dumb seeing it now
It's auto trans with a lot of mileage so it definitely doesn't worth doing any of those. I'll just suck it up until I get newer Civic.

 
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man, considering the amount of money I’ve poured on so far, I could’ve even bought RSX ‘04. Feels bad.

 
Rep Power: 222

A k swap is "bolt in" so if you're ambitious you could buy a wrecked/rotted rsx and have everything needed for the swap, the sell the remaining rsx and civic parts to recoup some of your cash

 
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Would love to, but this car is just too old and beaten to hold more power, especially transmission. I'll try to gather some money for few months and then try to get a stronger Honda.
But just for curiosity's sake, how 'easy' is swapping K engine to D17A?

 
Rep Power: 222

The trans goes with the engine, basically you drop the subframe with everything attached and the rear suspension. And remove one mount from the rsx and spot weld it in the engine bay. Plus ecu and such
Difficulty all depends on your skill level

 
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Haha, no I definitely can't do that much. I just moved my whole room's worth of stuffs in the car and it still was going strong so I'll just stop complaining, and just push the pedal a bit heavier from now on.

Cheers!

 
Rep Power: 222