English -> Car -> MODIFICATION -> Intake&Exhaust -1998.9.11 Updated-

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The reason why I exchanged it was impure. That is for a style from rear view and improvement of mileage per 1 liter. I chose FUJITSUBO LEGALIS because I liked a dual muffler, which had an European taste, more than a single one.

When they finished to change the muffler I was surprised at and worried about the big exhaust sound beyond my guess! The reason is that I talked with my wife about changing a muffler before,

"I don't oppose you but I dislike noisy one!" she said.

For few weeks I was driving it as slowly as I could when she got on it. But one day I moved with my family on high way. After passing the ticket gate my LEGACY sped up for the junction!

"You exchanged the muffler, didn't you? It's too noisy." she said.
"Re, really? There's no changing. Yes it's only your nerves!" I said.
"................ (she was smiled without words!) "

That's means she already knew it. Now I like the sound which I felt very noisy and the response which is better than before. Particularly those on high spinning range is indescribably wonderful and it makes me poisoning. But I feel the torque on low spinning range became weak. So it connects changing the air cleaner.

I'll say only one thing, "If you have your family, give changing a muffler serious consideration!!"

Air Cleaner

I changed air cleaner to the bare type one for improving the torque on low spinning range. It's MAX POWER FILTER made by Kuwano sold as "for LEGACY WAGON BF5NA no ABS".

By changing it the response really became better. But I'll have to say 3 points as follows.

(1)The bare type cleaner causes the state as the air flow sensor can't measure the quantity of flowing air exactly. The quantity of flowing air really is more than the quantity which was measured by the sensor so the mixture turned out to be thin. Gas itself works cooling the engin then a thin mixture will trigger off blowing the engin away at the worst time. Using AFC (Air Flow Converter) or rewriting gas map need for that correction.

(2)MAX POWER FILTER is wet type then only a little oil flow into air intake pipe. And LEGACY's air flow sensor is weak for dirt because it's hot plate type. So it needs that you often clean it by a cleaner for exclusive use.

(3)The bare type cleaner gets hot air in engin room. The efficiency of burning is lower than cool air so I advise you had better to get air around a grille or a bumper by using plate or pipe.

It passed 43,500km then I changed air cleaner to original clener case + FET FORZA. The reasons are the damage of cleaner itself and keeping away from dirt of sensor. For long, long riding, I think that it's better.

I changed FET FORZA to SUBARU genuine element.


AFC (Air Flow signal Converter) is the unit that it is put between the air flow sensor and ECU (Engin Control Unit) and by adjusting the signal of air flow it can control the mixed rate of air and gas. I bought APEX Super AFC

I installed it by myself too. At first I put the unit in. I didn't want to fix it to a vacant place with double-sided adhesive tape then I put it in 0.5 DIN space below the audio unit. At that time I was undecided what was good for the extra space at the side of the unit because the height was just 0.5 DIN but the width was not. Finally I manufactured the 0.5 DIN gadjet box to be suitable for the space. But I can put only a box of Short Hope (one of the Japanese cigarette). I'll make a simple voltmeter instead of the box at next time. That wiring was not so difficult but when I cut the cable of air flow signal I needed courage to do it with the thought as "Is this cable right? If the car don't work, what do you do?" (It needs to wire with some terminals. If I cut the different cable, it's no problem by connecting them again ...... It's too exaggerated.)

It's easy to use. I can adjust the fuel about +-30% every five spinning range. I can decide the adjusting point after the repetition of driving and moving the point. I think it's a useful unit.


ENGIN ...... An engin is the engin itself. I don't want it soon. I like the form of BF LEGACY very much but I think that the engin on BG or IMPREZA WRX is better than BF's frankly. I want to exchange the engin on a time because my engin becomes tired as the mileage increased. The target was IMPREZA WRX's a little before now. But now I changed my mind. There are more trouble on turbo car than NA car because a mechanism on a turbo car is more complex. For me it's important to use for a long time and I thought what needed to my driving, then the result is, 2.5 liter car, 250T's! I'll include it on my LEGACY! Of course, it'll be recognized officially!

This will be the most expensive plan about my LEGACY.

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