I was wondering if those of you who have headers and exhaust could comment on how noticeable the power difference was after doing these mods. I believe the dyno charts show roughly a
55-60 +- RWHP. After dropping several grand, did the buttdyno register something like
"Holy S*#t "!!! or was it more subtle?

 

That is all subjective to each person and how in tune they are to subtle changes. Yes, you can feel a difference. Does it feel a WHOLE LOT faster, NO. Is it decently quicker, YES. The most noticeable change will how much easier you can lose traction in the powerband of gears 1-3...that and the sound difference.

 

My butt dyno is on point!

 

i only have an exhaust and honestly, i can't tell a difference. but i sound faster! hell yeah!

 

Coming from 2 tuned turbo cars (GT-R and 335i) where I could REALLY tell a difference (night and day from stock), the IS-F is more subtle. I think trap speed changes are where the "feel" comes in. The 335i trapped about 100 stock and bumped to 110 with a simple piggy back. That was the biggest difference I've ever felt with one simple mod. The GT-R was a work in progress. 119 stock trap speed to eventually 126, but it was in stages trying to get the tune dialed in. But let me tell you, once it was finalized it was absolutely insane. With the F, I think we go from 110-112 stock to 116-117 (on average) with exhaust and headers. I believe if you did exhaust and headers at the same time you'd feel more of a difference than say putting on exhaust and then down the road adding headers. I can definitely tell a difference with the bolts ons compared to stock, but if you want wow factor, do both at the same time. Hope this makes sense.

 

Thanks for the input. If I go ahead with these mods, I will go ahead and do them all at the same time; Lowering springs, headers and exhaust. I did the Injen intake and Super Sport tires and wanted to see how other F owners felt after making the investment, was it worth it? I use to have an old Cutlass that I did the motor, tranny and very steep gears all at once........it was a spectacular contrast! This time around it will be refining something awesome to start with.
The F is a sweet ride!

J

 

I would definitely do headers and exhaust at the same time.

 

I did both mods at the same time and the most noticeable thing is the low end tq right off the bat. turn your wheel and let the gas have it and you will watch the car blow sideways with much ease compared to how it was stock

 

The F pulls like a demon up top once you get to triple digit speeds. The "butt dyno" is most noticeable there where you fee like the F never runs out of breath.

 

^^^this man tells the truth. Just had my sikky headers put on to go with my borla cat back and my Joez intake and at that speed keeps pulling hard! Love it.

 

Headers+exhaust make a huge difference in sound and speed on the IS-F! Its a night and day difference

BEST MOD evaR for any IS-F

 

Headers make a big difference. Much more than exhaust.

~Dv8

 

After installing a cat-back I could definitely feel a difference but it wasn't earth-shattering. Since headers and cat-backs both gain roughly 20whp, installing both would essentially double what I felt so it should absolutely be noticable.


I haven't done headers, but here are my experiences in order:

Borla Axle-back = Couldn't tell any difference at all.

Borla Axle-back + K&N intake = The intake is comically loud which made me think I was faster but after really trying to determine gains I felt that the car was actually slower once the ECU adapted to it.

JoeZ cat-back = I felt a bit more pull in the higher RPMs. It was noticable.

JoeZ cat-back + JoeZ intake pipe = Couldn't tell any difference.

JoeZ cat-back + Injen intake = Couldn't tell any difference but I like this sound combo.

 

Headers + exhaust = neck-breaking acceleration

 

I guess I am just used to it now. Passengers in my car are very impressed, but the straight line acceleration is just funISH for me now. It is fun as hell once you reach the twisties, but I don't think 400whp in a relatively heavy car snaps anything but the weakest necks