Hyundai Forums banner

Redesigned Exhaust

51K views 163 replies 32 participants last post by  WaveLxrd 
#1 · (Edited)
This made a huge difference in sound a decent power increase starting at 3k rpms.

Originally I had replaced the stock mufflers with Flowmaster Delta 40's and removed the resonator and kept all the stock piping.

However today, I got rid of all the stock piping along with the 3rd cat. I ran 2.5" exhaust to the Magnaflow Y-pipe I got at work then ran 2.5" piping to the mufflers. Much much better design for all you guys who want to do the exhaust. Here is the pix of the new exhaust. Cost $140 for piping and labor and $25 for the Y-pipe. Sorry for the bad pix. Enjoy!


 
See less See more
1
#7 ·
Originally posted by cmerica@Sep 28 2008, 07:41 AM
V, how hard would it be to make it an actual dual exhaust? And is it possible? Has anyone tried it??
[snapback]193239[/snapback]​

Well you would have to hack the manifold and do 2 really small pipes to make them fit down the middle of the car. Is is possible yes, Would I do it no. Doesnt seem liek there would be a much benefit
 
#9 ·
Thank you SO much haha! This helps a ton!
 
#10 ·
Ok, LAST question...about to order parts and wanted to make sure this all looks right...
 

Attachments

#13 ·
What’s the guesstimate cost for adding a dual exhaust on a 4banger? I’m more into looks than actual performance I know the limitations of my sonata and I’m very content with that. Would a transplant from a V6 Sonata be possible? I assume that all sonatas are made to hold a V6 could be wrong tho.
 
#14 ·
I'm sure it's possible to use the stock V6 exhaust setup - you can just look under your bumper to see if the hangers are there. Cheap mufflers/tips + install would probably net you $500 max depending on the place - I can't imagine it being more than that.
 
#15 · (Edited)
I took a look under my car and there’s a splash shield of some sort where the 2nd exhaust would be when I have some free time I’m going to take it down and see what’s hiding underneath. I would rather get a stock v6 exhaust then some cheap rattle cans. Guess ill have to find someone upgrading there stock V6 exhaust. Anyone here that has upgraded there exhaust keep there old mufflers?
 
#19 ·
Supernova,
Another concern is that you might actually lose power. When the exhaust gasses cool too much (in the extra piping) they actually restrict flow and cause a "plug".

On my Sequoia with 4.7L, many put larger piping and dual exhaust and the common complaint was they lost all low end torque for off the line and towing. Full throttle higher rpm it was a little better but not enough to warrant the loss so most switched back to single exhaust, factory size piping, low restriction mufflers and headers.
 
#22 ·
The only way to really know would be on a dyno. Where is that peak horsepower difference? At full throttle it should flow more as there is enough volume and pressure of gas. Down low?

I in know way to pretend I know all these things, that's what the engineers get paid for. I read many things and pick up a lot of info on my vehicles. For the Sequoia I really wanted the Borla/TRD dual exhaust as it looked good and sounded nice. A couple guys did dyno theirs after install and dyno confirmed the butt-o-meter increased hp at top rpm with noticeable reduction in torque low. These guys were also towing trailers and some through the Colorado Rockies. Low end grunt was way more necessary than racing. I think one guy did dual exhaust but made it smaller piping with almost same improvement result. Maybe you can find a junk yard dual sonata dual exhaust, bolt it up and be our test vehicle.
 
#21 ·
i think v33 mods his car way too much lol. still I do want my sonata look like his someday.
 
#31 ·
so no CEL after removing the 3rd cat ?
I went to a local shop to remove it and he said CEL may come out ?!:(
 
#32 ·
I went today to a shop to make them remove my third cat and install just a straight pipe in that section...

the guy took like 2 minutes to remove it and he showed me the "cat" which was no cat, but a resonator... so he suggested me to keep it because a straight tube won't get me more horses.

what I did was to start the engine and rev it up!, **** it was loud and deep and it revved faster.

then he just reinstalled the resonator... sad :/
 
#37 ·
lol.

is it true that the o2s don't check if there's a cat installed?

So I could buy the headers offered in Kspec and make a shop to install a O2 sensor at the same height the stock ones are?

this might be interesting

the point is to not get a CEL, **** the cats!, no one will know I don't have them lol (will have to install stock exhaust manifold for anual inspection.
 
#38 ·
i just bought used exhaust manifolds did away with the insides (large flat head screwdriver and rubber mallet/hammer). i am now contemplating whether i should insert and weld some piping inside the cats to eliminate turbulence but i noticed that diameter at the neck/collector where the 3 tubes meet is greater than the diameter of the outlet at the bottom of the manifold where i would plan to insert the tube to reduce turbulence.

heres a pic of my work so far. just waiting for my intake manifold to arrive and do it all at once.
 

Attachments

#39 ·
the mechanic wan't sure about the CEL, so after reading all your posts, i'm removing the 3rd cat tomorrow. and getting my nspp this weekend
thanks guys
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top