How good or bad is the original Honda EP3 OEM Exhaust?

[Linus27]

My EP3 has the original Honda OEM exhaust apart from the mid pipe which is an unsilenced sportex. The unsilenced mid pipe does sound very nice but does scrape of some speed bumps due to it hanging lower than the original OEM mid pipe. I am about to have Eibach Pro Springs fitted which is going to lower it about another 20mm so I really am tempted to put the original OEM mid pipe back on.

However, some say the OEM mid pipe is really restrictive. Is it really that bad the original OEM mid pipe or not as bad as some make out? I am also planning on doing some track days next year and considering a catback system like a TODA so should I put the original OEM mid pipe back on until then?

Interested in hearing how bad the Honda OEM catback system is really and if it is as restrictive as some say.

 

[howie1987]

I think the OEM backbox is good it should be fine up to about 300bhp

The midpipe is restrictive same with the cat etc but no use changing inless your getting map before you see big gains.

 

[dotty]

It's not bad if you're running standard power, when you introduce breathing mods and kpro (or similar) then you should consider changing.

I once ran with spoon b pipe, gruppe m and standard back box. It sounded nice but you don't really see significant power increases until the car is mapped.

 

[Linus27]

I currently have a ITG Maxogen induction and I was planning on getting a K100 remap at some point next year.

Is it not worth mapping with the standard Honda OEM cat back system as the gains will be so small, especially as I am running the ITG induction which is very close to the original Honda OEM induction?

 

[howie1987]

They wont be small just not as much as if you had somthing like toda or spoon on but its still worth it. but when you come to put on other parts then you will need the ecu retuned again.

So its best if you get everything done at the same time and then get it mapped, i learned the hardway lol

 

[Linus27]

They wont be small just not as much as if you had somthing like toda or spoon on but its still worth it. but when you come to put on other parts then you will need the ecu retuned again.

So its best if you get everything done at the same time and then get it mapped, i learned the hardway lol

Thank you. So if I ended up keeping the Honda OEM cat back system then its not too bad even with a remap but if I do change to a TODA then do that before the remap. As the car will be lower with the Eibach Pro springs, I need to decide before Saturday to put the oem mid pipe back on in case the scrapping gets even more problematic or to risk keeping it on.

 

[howie1987]

Yeah if your going to do it in the future anyway you are aswell get it on before the remap and if you plan to put like a decat on etc i would change all that before the remap so then it will be tuned to they parts on the car.

 

[Shoonk]

The OEM is quite good, upgrading really changes bore size and the materials used means the exhaust gases are more free flowing. The Spoon b pipe and similar branded ones run a 2.5" bore size you don't really need this size unless your uprating big time like inlet manifold, induction, header or supercharging etc with this size you lose on acceleration and gain top end due to back pressure (That's what I was told by a couple of different exhaust fabricators). You could go for a 2.25" slightly smaller bore b pipe or use the OEM seems your not tuning big at the moment this should give you a bit of ground clearance when lowering.

 

[Linus27]

The OEM is quite good, upgrading really changes bore size and the materials used means the exhaust gases are more free flowing. The Spoon b pipe and similar branded ones run a 2.5" bore size you don't really need this size unless your uprating big time like inlet manifold, induction, header or supercharging etc with this size you lose on acceleration and gain top end due to back pressure (That's what I was told by a couple of different exhaust fabricators). You could go for a 2.25" slightly smaller bore b pipe or use the OEM seems your not tuning big at the moment this should give you a bit of ground clearance when lowering.

Yep, no intention to tune big now or in the future. Just stick with the ITG induction, JDM Rear Arb, Eibach Pro Springs, DS2500 brake pads, TGM braided brake lines and then remap. For now I might just stick with OEM cat back system if its not that bad a system and if I decide to go for a new cat back like the TODA then I will do this before the remap.