Currently have a 97 Civic DX. Stock D16 engine 111xxxmiles N.A. with
DC sport headers, MSD ignition with blaster coils, AEM Dry Flow air intake, AEM TRUTime Camshaft adjuster and a GReddy TurboXS exhaust system with no catalytic converter. The car is still slow and im not sure why.
The diameter of the muffler is around 4inches and very noisy. Ive been told that bigger is better but others say that its too large and I should switch it out. Not really sure what else to do but any feedback will help.

Just trying to make it faster but not sure what else to do. Also trying to keep it natural because of the mileage, not so sure a turbo will make it last.

 

slap the person that told you bigger is better because in exhaust cases its not true.. see the reason for the smaller exhaust and what not is that it help with back pressure which is what actually keeps the fuel inside the cylinder its called the scavenging effect.... if you lose too much back pressure you WILL lose HP and TQ and will actually make your engine run hotter because it will lean it out

 

sounds good. so a nice muffler switch should do the trick? or replace the exhaust itself? the piping itself doesnt look to big its a custom job with pretty much a straight pipe all the way back but as i said that muffler is a beast

 

just the muffler is 4in around thats not too bad thats not really gonna make too much of a difference.... not really too much more actual bolt-on power-adders after exhaust and intake maybe a few other little things but if i was you id just do a rebuild or get an engine and build it while your using that engine for your dd

 

well i mean the muffler tip is 4inch around but the muffler itself is massive, about twice the size. i was considering a turbo using a low psi or a new engine. wasnt sure which would be cheaper or even what engine etc because im on a budget. too much to consider

 

Back pressure is a myth, if your header was designed well then you could use a 5" exhaust and it wouldn't hurt performance. Your car is still slow because it only has about 110 hp. Don't waste any more money or time on the D16Y7, save some money, buy a swap, and do it right.

And please, do something about that wiring!

 

backpressure is not a myth its what keeps the gas in the combustion chamber and not flowing through the exhaust valves thus leaving less fuel in the combustion chamber which means less power and possibly leaner mixtures

Manifold (automotive) - Wikipedia, the free encyclopedia read it

 

If you have the car tuned (like you should after modifying an engine) then more back pressure will only hurt performance. The biggest reasons why exhaust size generally stops at 2.5" on Hondas is that 1. Most Honda engines are not built enough to utilize a 3" and 2. It costs more for a larger exhaust. Most people make the most power open header. Its all about the header design, HyTech makes more power than DC Sports for a reason.

Wikipedia isn't a legitimate source anyway.

 

with a highly modified, tuned car youre right but with this set up big exhaust will not help his performance it will actually decrease performance

 

I'll agree with you about a big exhaust not helping hp for this set up.

A large exhaust will benefit any engine setup as long as it is tuned for it. I don't think the OP is interested in having the car tuned or actually researching any REAL performance upgrades. IMO that EK is begging for a H2B.