Any way to boost power for 2003 Sentra 1.3L AT?

**tinsami1** · August 9th, 2008 07:40 PM

Hi tsikoteers.

Currently, I'm driving a 2003 Sentra 1.3L A/T. I'm not complaining, but medyo mahina sa pataas. When I'm driving alone, I switch off the a/c to squeeze out more power. Are there any mods I can do to the car to boost the power?

**niky** · August 9th, 2008 11:13 PM

The simple answer is yes...

But how much power do you want and how much are you willing to spend?

On a 2.5k budget, forget it. Stuff you can buy in this range, like Simota air filters, will give you crap for power. (most of us buy Simota for the tubes, throw the air-filters away and buy K&Ns, which cost another 4k).

If you have catalytic converters, though, you can remove one (don't remove both... might not pass emissions) and replace it with a straight pipe for about this much. Gives you about 2-3 hp.

On a 5k budget, you can get a K&N air-filter, which will give you typically 3-5 hp. Enough to feel, but not enough to make a big difference in how the car runs.

On a 5k budget, you can also get a set of really cheap headers. But the thought of putting something that looks like it belongs on a tractor inside a car that's worth over 600k pesos brand new isn't appealing to me.

Around 10k, you can buy or build a cold-air intake with a good air filter. About 5-8 hp. But this is vulnerable to water damage in floods (goodbye engine).

On a 10-15k budget, you can buy good headers (either secondhand or chinese original or brand new mandrel bent stainless). Well designed headers in this range can make 8-12 hp (15 if you're really lucky) and this may be all you're looking for if all you want is some kick. But with an automatic, the design of the headers should be optimized for low-end power. Most commercially available headers are designed to make more power in the higher rpm ranges and aren't much better than stock (and sometimes worse) at low rpms. Take note that buying headers removes your primary catalytic, which is responsible for about 3 hp of that gain.

At 20k-30k, well, you can buy a cold air-intake and header combo that'll give you a decent kick (about 10-15 hp) and is probably all the power you'll ever need if you're not a racer.

Alternatively, you can buy a piggyback computer that'll make 5-15 hp . While that may seem low since less money can buy you parts that make that much, a piggyback computer can make that power everywhere. Your typical intake-exhaust combo will make more power in some places and oftentimes less power at low rpms. A piggyback computer like the Unichip can make power everywhere, and often gives a good spike of 10-15 hp at midrange rpms, just where you need it for everyday driving. Oh, and it can improve fuel economy, too. Only drawback is that it takes a few days to install one... so be prepared to live without your car for a while.

----

Those are the simple answers. Best case scenario is 15 hp... and if you push it, maybe 20 hp with 50-60k pesos worth of mods.

If you want a drastic difference in performance, best bet is to sell the Sentra and buy either a smaller car with the same sized engine or a Sentra-sized car with a bigger engine. The QG13DE is a decent engine for its size, but the automatic transmission isn't built to handle a whole lot of power and it'll cost a whole lot of money to make the 1.3 as powerful as an ordinary, unmodified 1.6. A ton of money. I know guys who've really built 1.3s, good intakes, full exhausts and even camshafts... but they can't even come close to the performance of a 1.6. A turbo would make a ton more power (and you can do cheap builds for under 100k pesos) but I don't know if your transmission can take it, and spending that much money just to make the same power as your typical 1.8 or 2.0 engine is kind of insane.

It's even worse on your Sentra because of that automatic and because the Sentra is relatively heavy for such a small engine. Hell, I used to have a Sentra FE 1.3, which was 200 pounds or more lighter than your car (and manual, too!) and we threw everything at it in terms of mods, and it was still slow (but fun

).

**ghosthunter** · August 10th, 2008 09:25 PM

Curiously, do you do your periodic maintenance?

**tinsami1** · August 10th, 2008 11:25 PM

Originally Posted by ghosthunter

Curiously, do you do your periodic maintenance?

Yes. Casa-maintained. My wife used the car since it was bought until we bought an Innova last June. Now I use it for my daily commute (Munti <--> QC).

**tinsami1** · August 10th, 2008 11:39 PM

Hi niky.

Thanks for the lowdown. I'm not looking to race with it. I just use it for my daily driving to/from work where I'm the only passenger most of the time.

I like the idea of the piggyback computer. How much will such set me back?

Alternative, can you recommend a shop for the cold air intake + header combo? Pag-iipunan ko pa ito. My short term need is to have the shocks replaced. Baka Nov or Dec, pag-sinwerte I may have enough cash for this.

Thanks again.

**niky** · August 11th, 2008 02:35 PM

Originally Posted by tinsami1

Hi niky.

Thanks for the lowdown. I'm not looking to race with it. I just use it for my daily driving to/from work where I'm the only passenger most of the time.

I like the idea of the piggyback computer. How much will such set me back?

Alternative, can you recommend a shop for the cold air intake + header combo? Pag-iipunan ko pa ito. My short term need is to have the shocks replaced. Baka Nov or Dec, pag-sinwerte I may have enough cash for this.

Thanks again.

Cold Air + Headers, I get my work done at Speedlab. But they'll have to custom-design for you, as they don't have mass-produced headers for the Sentra. You can also try Mufflerland or Brodeth for headers... Mufflerland is cheaper, but quality is just as good.

Piggybacks are commonly around 15-30k... 30k for the kind I have, but that's inclusive of installation and tuning (if you get another kind, expect to add about 5-10k pesos for installation and tuning on top of what you pay). You can get the Unichip at Speedlab for 30k, including installation and tuning.

But you have to decide for yourself if it's worth your money. Like I said, tuning a 1.3 for extra "oomph" is usually a fruitless task.