Does it add hp & better sound if I remove the rear exhaust muffler?

[lancerevo]

Hi

I have a Kia Pride with the b3 engine.
Does it add hp & better sound if I remove the rear exhaust muffler and put a resonator instead, like the one in the middle of the car? My car have no cat. Does resonators restricts air flow?

Thanks

[TominMO]

The car will probably be too loud without a muffler; I don't think that putting a resonator in place of the muffler is a good idea. This might even reduce power.

One way to get more horsepower for free is to drill 25 or 30 holes inthe bottom piece of the airbox. This will let in more air than using just the small intake hole which is there. Your engine will rev up higher and more freely. Try it before anything else, since it's free.

[festivaWES]

You won't noticably feel any HP out of either of those mods, but they are free though. The car will be too loud leave the muffler on there or replace it with a cherry bomb, or thrush.

[Banana Bonanza]

At normal speeds daily driver type speeds, you wont gain anything but noise and actually may lose some power. Unless you increase intake flow and have an engine that can use that increased flow, then opening up exhaust system wont add power. This little feedback carb is probably pretty limited on flow as are the manifolds and the head isnt ported to use any increased flow. Its all a system. Let it have increased flow, even done properly in balanced way, and all you do is increase power at top end, maybe even hurting performance at low speeds. Race cars can use this as they run high rpms all the time and are looking for that last ounce of power. On daily driver, regularly going over 4000 rpm and probably over 3500 rpm just shortens life of your engine and eats fuel. Mileage and longevity probably maximized by shifting to keep it 3000 rpm and under. Fun has a price tag.....

Check for any kinks like where exhaust pipe goes around the gas tank, easy for it to get bent there without notice.

[sodikartracer]

i ran my car with a cat and resonator for a long time (no muffler) and enjoyed it wasnt to loud for me. but i dont know how yours will sound with out a cat, good luck making it work

[TominMO]

The holes-in-the-airbox thing only matters at higher RPMs, in case that was not clear. That little intake hole is adequate up to around 3000 - 4000 RPM; above that it can't get enough air in quickly enough to do the motor justice. I do this mod on every car I own. It made a very noticeable diffeence on my 91 Subaru.

[lancerevo]

air flow is not a problem because, it have a hood scoop and a cone air filter. The engine is efi.

[bhazard]

The little b3 just doesnt flow enough for exhaust to make a difference alone.

[TominMO]

air flow is not a problem because, it have a hood scoop and a cone air filter. The engine is efi.

OK, didn't know you had a cone. But most cars can't make use of all the airflow the cone can provide, without extensive intake and exhaust mods; drilling a bunch of holes in the bottom airbox piece probably does as much or almost so, for no cost.

[solatare]

i dispute the fact the b3 wont benefit from an exhaust.
i had an 90 efi 5 spd that i drove to work everyday over a mountain pass at 5000 ft.
total drive was about 150 miles aday.

heres my experience and the mods the car had:

bought for 300 dollars, gave it a complete tuneup(plugs wires cap rotor, it had a kn!?, so i cleaned it.) in this state it struggled to pull the top of the pass at 45 mph with just my 170 pounds in it. no idea on rpms as it did not have a tach, but i was pinned in 4th.

2 inch header back exhaust, atx distributor, 20w50 synthetic, removed rear seat and passenger seat:
of note, i did have a cat. a resonated high flow cat, muffler was also 2 inch. both from magnaflow. nice tone, and boy did it wake up, i got a tach cluster from fms and with these mods the car would do a steady 60 mph up the grade in 4th at around 4 to 4300 rpm, depending on wind, with a little pedal left. it wasnt anything amazing, but it was definitly
fun to drive. by my feel i was thinking of upping the exhaust to 2.125 or 2.250, but only because of the high rpms i ran in the hills i live on. i rarely got to use 5th gear.

car also passed smog just fine at around 270k miles.

[TominMO]

i dispute the fact the b3 wont benefit from an exhaust.
i had an 90 efi 5 spd that i drove to work everyday over a mountain pass at 5000 ft.
total drive was about 150 miles aday.

heres my experience and the mods the car had:

bought for 300 dollars, gave it a complete tuneup(plugs wires cap rotor, it had a kn!?, so i cleaned it.) in this state it struggled to pull the top of the pass at 45 mph with just my 170 pounds in it. no idea on rpms as it did not have a tach, but i was pinned in 4th.

2 inch header back exhaust, atx distributor, 20w50 synthetic, removed rear seat and passenger seat:
of note, i did have a cat. a resonated high flow cat, muffler was also 2 inch. both from magnaflow. nice tone, and boy did it wake up, i got a tach cluster from fms and with these mods the car would do a steady 60 mph up the grade in 4th at around 4 to 4300 rpm, depending on wind, with a little pedal left. it wasnt anything amazing, but it was definitly
fun to drive. by my feel i was thinking of upping the exhaust to 2.125 or 2.250, but only because of the high rpms i ran in the hills i live on. i rarely got to use 5th gear.

car also passed smog just fine at around 270k miles.

On a car with no mods, just about anything will help at least a little--airbox holes, K&N filter, header, etc. Drill some holes in the bottom of the airbox (if you have an airbox) and you will free up some of the K&N filter's freeflowing ability; it is limited by the stock hole coming into the airbox, just like the stock air filter is.

To me, the optimal B3 would have a K&N, airbox holes, FMS header, gutted cat (where there are no inspections), catback exhaust no more than 2". You could go with a cone, but I think that is just a cosmetic touch (which is fine too), but no real improvement over a stock-sized K&N and airbox holes.

BTW, your K&N--did it fit in the aribox or was it a cone? If it fit in the airbox, what's the part #?

[solatare]

gutting cat is a no no. tryd that. basically adds a big chamber like on a 2 stroke. but on a four stroke it stalls flow and spikes egts. nearly cost me the engine on a turbo eclipse i owned.

also, a good high flow cat will take less than 2hp from a street car; unless youre running race fuel and going for the top spot in a competition, its alot easier to just run the resonated cat for 80 or so bucks and save your ears and attracts less attention.

also dodges cops with remote sniffers in smog states. ask me more about that and what could happen...

[Festiva_tunner]

also dodges cops with remote sniffers in smog states. ask me more about that and what could happen...

It doesnt matter if they want to test your car they cant give you a ticket for it unless your car is registered in an area that does testing. Thats why my truck was registered at my mothers house while I lived in Nashville

[pyrothehitman]

adding more hp is not likely with just resonating the same airflow....to get more hp you have to increase the air intake volume...more air equals more hp...u can always fine tune and get 1 or 2 hp out of existing set up or resonator...but nothing noticable. hope this helps