As some of you know my modifications already..

CAI > UDP > TORQUE DAMPER
CAM > CAM GEAR > HEADERS
2.25" ZORST > HFC > ECU PB

I was thinking of upgrading to a 2.5" exhaust and tune it to that. That should give me some top end power by freeing up the airflow. What do you guys think of a 2.5" exhaust on a N/A car with the above modifications?

*I've searched and yes, I've read most of the info. Just want info based on my mods.

Cheers.

 

i think 2.5 is fine, any bigger and it wont do ya any good unless you're planning on going turbo

 

sounds like a perfect set-up go for it.

 

Sweet, others? Dan, PR, Otter, Stevo, Migue, Kreep, anyone else I've missed..?

 

lol, I dont know why ur asking, lol.... U know the answer. You semi hardcore setup demands it...hell Im going to get 2.5 in mine and I dont have cam or associated hardware. And mine's gonna be a straight pipe to 45 degrees mandrel bend

 

Your going to give up lowend torque for the high end power...if thats what your looking for ie peak power, thats fine. Buts it going to come at the expense of low speed drivability..2-2.25 should get you both...

 

yeah, 2.5 is gonna help you achieve your goal here. I still recommend the head job though(it will give you much more top and, and as long as the cam was done well then a good bump down low too), but you can do it in either order at your point in modification.

making the move from 2.25 to 2.5 you probably won't notice too much gone on the lower end, but you should notice it pick up a bit over 5000. the headers, cam, exhaust and high flow cat are pushing plenty of air, and with things freed up like that your torque has already suffered alot (the numbers changed by the cam are iffy, as it depends alot on the profile). enough for you to notice the increase more than the decrease anyway.

you are turning this into a honda though, you know that right? I keep thinking you next pm is gonna be asking about moving the redline to 8500

j/k good to see you are doing some research though

 

Haha thanks to all for your input, greatly appreciated.

Yeah I really want the head job (so to speak) done too but the problem is, head cyl + im will cost me about $2000-$2500 AUD. Quite pricy imo. I can just go custom turbo for that matter.

But besides that point, RPW won't release to me the specs on the cam. I understand its their profile etc but I bought it - lol. Who knows, I'll just pull it out and look at the specs myself.

lol @ turning the car into a Honda. (cracked me up man, made my morning haha) Actually in regards to 8500rpm, I actually PM Juan in regards to his ECU haha.

I just know that my car can perform better than its current state, and the car doesn't deserve such justice.

In the coming weeks:
Dyno run + obtain AF ratios
Purchase 5zigen Fireball exhaust
Then setup a 2.5" mandrel bend stainless steel exhaust
Then go in for a tune.

 

Well I have 2.5 straight from the header with a resonator and a REAL high FLOW cat not one of those $65 dollar ones sooo...

 

I was planning on doing a 2.25 from cat then 2.5 from axle so you have alittle back pressure

 

BTW, if you plan to go turbo (RRM Specifically), keep it 2.25.... Any larger and you get boost creep... I understand a few guys with bigger exhaust have issues with it... So NO, bigger exhaust not good for basic turbo setups... Custom, higher PSI, maybe, but not for 7-8 PSI...

 

I have the RPW HFC.

Can you give me a review on your 2.5" exhaust there Migue. From low-mid-top end. Have you dyno'd your car yet?

Also, is yours a stainless steel mandrel bend?

And how did you angle the muffler, our perches are in the way!

 

I thought you were selling your car?

 

2.5 will be good 4 you

 

Okay, seems i'll head down this path.

Also, will a muffler with a 2.33" piping fit to a 2.5 exhaust pipe? Or must I find an muffler with the correct piping to fit to the 2.5" exhaust?