Before I go to Engine Dynamics?

[Cup1/2Full]

I've booked into Engine Dynamics for a remap August 10th.
172 Cup K&N, De-Cat, K-tec cat back exhaust system.

On start up, sometimes the car feels as if there is some kind of pressure build up in the exhaust and then it coughs and splutters before clearing itself. It feels like there is a flat spot in the rev range around the 5k mark, and the car is quite thirsty. But the main reason is I've convinced myself to have it done.

Before I go though, I want to replace the K&N with a standard airfilter box as I have read on here they are better for the mid range, and will also take some noise from the system. (However after posting on here and FB and searched eBay I'm having difficulty in finding one at a resonable price)

I also want to fit a cheap eBay 200 cell MOT friendly cat, mainly in the hope of making the exhaust a little quieter.

As I've also just bought a knock off Dremel rotary tool for a DIY refurb to the wheels, I thought I might have a go at DIY matching the inlet manifolds as I don't have the RS one.

I used to break Maza RX8 and sell the parts on eBay. I'm great at taking things off, fairly good at getting things back on, but lacking in knowledge as to why I'm doing things.

Worth doing or better just leave well alone, thoughts, opinions, tips?

 

[Louis]

I've booked into Engine Dynamics for a remap August 10th.
172 Cup K&N, De-Cat, K-tec cat back exhaust system.

On start up, sometimes the car feels as if there is some kind of pressure build up in the exhaust and then it coughs and splutters before clearing itself. It feels like there is a flat spot in the rev range around the 5k mark, and the car is quite thirsty. But the main reason is I've convinced myself to have it done.
Pretty normal and just needs to come out of the cold map. Mines the same even after new injectors and lambda. Let it idle for longer before driving off and you wont notice it.
Before I go though, I want to replace the K&N with a standard airfilter box as I have read on here they are better for the mid range, and will also take some noise from the system. (However after posting on here and FB and searched eBay I'm having difficulty in finding one at a resonable price)
What's your filter now? Look into a ktec or fatty for ultimate noise. You probably lose a little mid range but itll be negligible.
I also want to fit a cheap eBay 200 cell MOT friendly cat, mainly in the hope of making the exhaust a little quieter
Decent idea, especially if running a standard cat now as it's worth good money. Fit a 182 manifold if you're wanting some more mid range torque, requires the subframe dropping but easy enough for ED.
As I've also just bought a knock off Dremel rotary tool for a DIY refurb to the wheels, I thought I might have a go at DIY matching the inlet manifolds as I don't have the RS one.
Not worth it imho, so cheap nowadays for a shop to do your wheels.
I used to break Maza RX8 and sell the parts on eBay. I'm great at taking things off, fairly good at getting things back on, but lacking in knowledge as to why I'm doing things.

Worth doing or better just leave well alone, thoughts, opinions, tips?

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