Hi all...just a quickie...

I recently go a cat back 2.25" straight thru under axle system with a apex N1 muffler for my EG5 (Australian version of JDM ZC - DOHC D16a8 , 130hp) ...







Ok...pix aside - I am running STOCK headers and b-pipe - soon to replace with ZC 4-2-1 OR 4-1...

At this current setup ( this system, + TRUST hi flow filter and CAI) this car pulls alittle less below 4000rpms , but is hugely peaky with top end increased a crap load !

What i want is, a good level of torque throughout - and this is in my headers.

Are 4-2-1 and 4-1 drastically different to each other ? I realise the latter is more top end and vice versa , so i SHOULD get the 4-2-1 to increase bottom end too ?

Hmm...any thing else ?!?

Thanks ! Ben

 

I put a cam in my head and had it retarded. With a stock cx (real crappy) exhaust manifold and cat, it would pull ok down low and scream in the upper RPMs. I changed to a better header(4-2-1), and I lost ALL my low end! It pulled the same in the upper rpms. I advanced the cam, and now it pulls much better down low. Moral of my story, A header may really cripple your low end without tuning. Get an adjustable cam gear to shift your powerband.

 

Your exhaust may be too big for your set up. The ideal set up is where there is zero restriction on exhaust flow, but it is also small enough to mantain good exhaust velocity. Rick