News:

Welcome to the AutoIndustriya.com Car Discussion Forums!

Main Menu

Help on exhaust system

Started by Edwin, January 28, 2003, 03:29:13 PM

Previous topic - Next topic

Edwin

Guys, need your expertise.

I recently got my 4-1 headers last week from Ex Manila, its a crush bent with spoon specs.

Prior to the headers, I was using my stock exhaust manifold but was bored out to fit the ported exhaust. I think 17 and sucat nung port holes which was perfect for the headers.

Anways, aside from the stock exhaust manifold I had pipings installed from Nodalos with the resonator. Pipings were 2" and laslty my muffler was an original N1 Spoon muffler.

Before the headers, I find my muffler to noisy but really deep ang bass sound. Kahit low rpm, umiingay na sya. Due off course dahil naiipit sa stock manifold ko lahat ng pressure.

With the headers installed ito yung mga napansin ko;

1. Di na sya masyadong maingay at low rpm umiingay lang sya at 4,000 rpm above. - this was okay

2. At high rpm mas mabilis and respond ng engine and bumils sya pero medyo nawalan ako ng torque at the low end - still this was fine.

3. If i step on the accelerator until 6,000 rpm then release the pedal, me parang back pressure sound sya na lat na matinis....enggggggggggg...(parang naririnig  nyo noh? juz use your imagination). And it was coming sa ilalim ng front seats and not the muffler.

I brought it to Nodalos to check for leaks, wala. Then I called up Mang boy ng Ex Manila, his first and only suspect was the resonator. Baka daw wala nang laman, usually kase either me foaming (yun ata) or fiber gglass sa loob. My questions are;

1. Is this true? Is the resonator the problem?
2. Or kailangan ko mag switch to 4-2-1 which is way to expensive at this point since nabili ko na yung 4-1?
3. Or are there any other suspects/ reasons kung baket ganito tunog.

Hope you guys may have the answers.

Thanks!

To dream anything that you want to dream. That is the beauty of the human mind. To do anything that you want to do. That is the strength of the human

juny


EdwinM

Its a 1998 Honda civic LXi, maroon (red sa rehistro).

Brent

First obeservation, wala naman 4-1 na header ng Spoon for SOHC engine. If the one used for DOHC engine is used in SOHC it would'nt work correctly for the matter that it was designed for DOHC and not SOHC. And I personally think better parin ang 4-2-1 for SOHC engines, based on observation on friends' engines.

With regards to your piping, parang bitin ang 2-inch since highly modified na ang engine mo, mga 2-1/4 pwede pa diyan. And if you are still using stock resonator, please do have it replaced to match your new system. Problem would be the size of the resonator since it is not just a matter of making a resonator. Your regular muffler shop can make you a resonator but not of the correct specs and WILL make your car slower.

Try to ask your mechanic to compute a resonator size for your car.

nukee

Well, i also think it's the reso.

I used to not believe it but the reso can make a big difference.

When i used the reso of fremuff, bumagal pa pala ung car ko at nawawala ung tunog ng vtec ko.

Nway, i replaced it with the original ones from japan surplus, and my car got faster.

And now, sumisigaw na ung vtec ko, literally sumisigaw talaga kasi nag down pipe pa ako. Nakakaaliw ung tunog.

So edwin, how much did you buy the headers, may bend ba yan o pinutol putol tapos dugtong dugtong?

Edwin

brent,

thanks pare...actually i wanted 4-2-1 but my mechanic told me since kulang talaga ang lxi sa dulo (hi end) so it was better to get 4-1. Sa piping its my fault my mechanic told me me 2 1/4 or 2.5 kaya pa naman daw pero ako yung natakot baka mawalan ng torque. Sa resonator, its nodalos 18 inches computed na ng mechanic ko per the problem is I bought the black iron. I already went to both ex manila and nodalos. Its really the resonator, yung ginamit ng fiber glass ng nodalos sa black iron nila is not the plastic type but yung parang foam. So i might either change to an aluminum resonator and also recheck the piping size.

To tell you frankly, parang bumagal pa nga kotse ko after the headers was installed. my time slip last dec. 14 indicated 16.7 while this time sa clark my best was at 16.8. Need to reconfigure my exhuast system again.

Nukee,

sa ex manila its 3,200 pwedeng tumwad up to 3thou...bend tapos putol putol...okay lang sya pero nothing beats the original like dc.

Thanks for the help guys.
To dream anything that you want to dream. That is the beauty of the human mind. To do anything that you want to do. That is the strength of the human

kiro

i'm so sorry for my ignorance, pero what does a resonator look like? ::)

un ba yung nasa ilalim na parang mesh cone, or something like that? kasi nung naginstall ako ng headers and piping hindi sya pinalitan...

clyde

Quote from: Edwin on January 31, 2003, 10:28:52 AM
brent,

thanks pare...actually i wanted 4-2-1 but my mechanic told me since kulang talaga ang lxi sa dulo (hi end) so it was better to get 4-1. Sa piping its my fault my mechanic told me me 2 1/4 or 2.5 kaya pa naman daw pero ako yung natakot baka mawalan ng torque. Sa resonator, its nodalos 18 inches computed na ng mechanic ko per the problem is I bought the black iron. I already went to both ex manila and nodalos. Its really the resonator, yung ginamit ng fiber glass ng nodalos sa black iron nila is not the plastic type but yung parang foam. So i might either change to an aluminum resonator and also recheck the piping size.

To tell you frankly, parang bumagal pa nga kotse ko after the headers was installed. my time slip last dec. 14 indicated 16.7 while this time sa clark my best was at 16.8. Need to reconfigure my exhuast system again.

Nukee,

sa ex manila its 3,200 pwedeng tumwad up to 3thou...bend tapos putol putol...okay lang sya pero nothing beats the original like dc.

Thanks for the help guys.

pre,

i guess it's time to go for a dyno. with all those mods and efforts u have, i think it's time to pay a visit to a local dyno. ur exhaust is one of the contibuting factors but mainly the engine should speak first. i'm sure u'll get a baseline to start with.

as what Bob Norwood (Kenny Tran's 8 sec. civic head tuner) say's "it's all about reacting to changes and solving problems.

just my 2 cents. :)

Edwin

clyde,

Thanks, ,ukhang dyno tuning pa nga ata kailangan ko. will do chief. thanks for the input.
To dream anything that you want to dream. That is the beauty of the human mind. To do anything that you want to do. That is the strength of the human

Subscribe to our channel
subscribe to our youtube channel