Hi guys, here is my problem :
I installed a pacesetter header(few weeks ago) with a catless dp 3" that narrows to 2.5" at the end. I have a defouler kit too, because I'm not tuned.

Between 3.2k and 3.7k rpm, I have a huge loss of power. But, after 4k rpm, I have a big power gain over stock manifold/dp.

How could I solve the power loss(if it's solvable) :

Put a cat on it(more restriction)?
Get a 2.5" dp?
Get a tune?

Only other mod is a CAI. I have stock catback(and it sounds like crap).

Thank!

 

Turbo

 

get a tune.. the car is setup for a shorty manifold not a midlength the scavenging properties are totally different

 

what size primaries? If you got 1.75 you can't really tune this out because the exhaust velocity just can't get that high anymore with such big primaries. High exhaust velocity= mid range torque.

 

1.5" primaries. I may consider a tune later... ty guys

 

Should have gotten a tune off the bat once you toy with headers. Car will run much better and more reliable. I've gone down that road before.

 

Well it's good that they're only 1.5" Get a tune and it will feel much better, I suggest HPT but Trifecta is always an option

 

If it's not tuned, it's near worthless to even do. Huge gains made on my buddies 2.2 with VVT. Got it tuned and car pulled alongside my stock LSJ without issue.

 

Oh well I know where i'll spend my next spare 250$! But im worried about the warranty... I may wait for next summer to do this, when warrantg will be gone.

 

your shift in powerband is a product of your exhaust choice...

if you want low end power pick up a shorty header and a smaller downpipe...I personally wouldn't bother though

 

Well I got this header almost free, I had to try it.

But, I went drag racing yesterday and now my exhaust is louder and sounds like marbles are in it when I shift. I may have a exhaust leak or my muffler died from the extra flow/heat. I'll check that next weekend, maybe going back to stock.

 

get a tune bro it'll solve all your problems

 

what defouler kit do you have? i get a cel with my zzp 2.5 catted dp and i tried the vibrant one and well it got rid of the cel but then caused a different cel "rich to lean lean to rich" weird.

 

I have a cheap kit from ebay. CEL comes each time I downshift at high rpms, when it does backfires (P013F)

 

After checking the install to make sure all your stuff is installed properly get a tune. I installed my vibrant headers on my old 2.4l and noticed modest gains, great improvement in the depth of exhaust sounds, but then after a tune... holy ****. Tune + headers = win. I also got lightweight pulleys and an engine mount, which made it put power to the ground alot faster.

 

Get it tuned! That RPM spot is kinda a dead spot anyway but a tune definitely helps!

 

Oh thats not good i need something to completely rid of cel the vibrant defouler dont work. I have inspections here. Getting sick of swapping to stock dp lol. I dont wanna tune tho and i read someone say i still wont pass inspection with it tuned off

 

Rear O2 doesnt affect how the car performs FYI

 

It did for me the car would lean out at idle and run a little strange. Got more afr flutter on my wideband than normal and that caused my cel for lean to rich ruch to lean not sure of code numbers. This is with using tje vibrant defouler. I completely removed the rear o2 sensor and the car ran much much better lmaoo but i put it back in and ditched defouler and deal with 420 code which isnt a problem the inspection is and i haveto swap to stock dp its a pain in the ass.

 

1.5 is good for NA cars. But I tried 1.75's on a zzp midlength and raced my buddies car and before Id pull him slightly downlow and hold my ground till 90mph. (stock manifold) with a zzp midlength and the 1.75's I didnt pull him downlow id hold my ground but after 35mph id just keep slowly creeping away from him. Now I have a zzp shorty and the lowend is back but it doesnt pull as strongly uptop. With my current setup I pull him slightly less downlow a bit more than with the stock manifold in the midrange then none at all uptop. btw he has a 97 civic with a B18b1 full exhaust pro1 intake manifold B16 trans runs consistent 15.5's. So I figure either way for an auto 2.4 with only intake and exhaust with no tune Im doing pretty good.

So honestly I will probably be going with the zzp longtube and 1.75 primaries but thats also so I have some room to grow in the future.



To the OP: Get a tune.

 

but then u lose low end lol thats the problem with na 4cyl

 

I didn't lose that much lowend is my point. I'm an auto and I was still able to spin 235/40/18 summer tires for 3-5 feet just flooring it from a stoplight. It maybe an na 4cyl but its a decent size 4 with fairly high compression. Its not as bad as many people think. It doesn't suddenly turn us into b series hondas.

 

Coming from stock these cars pick up some good power.

 

I may have some of the same issue. i went to the tack this past Sunday. last time i went i had a K&N SRi adn a Megan cat back. ran a 14.9. went back with a ZZP Midlegth/catted DP, GMPP Cat back, LSJ TB and K&N Intake. best i could do was 15.1. i was having traction issues, but i feel i desperately need a tune! car should still trap faster than before and its not

 

Well thank you guys! I am now used to the dead rpm spot and love the high rpm now, I can feel the difference in my butt dyno. Next summer is going to be CM springs and trifecta tune.