I have my car apart to replace the clutch and Im in no rush as I have another car so Im changing all the seals , gaskets and suspension stuff etc . I was thinking about porting and polishing the TB and the air horn section that exits the IC . The inlet side would require removing the intake or supercharger and I have enough work . I realize it would offer no great increase in hp but its been my experience that a little here a little there adds up . Currently WMW exhaust CAI 15% 2%crank .
I did a search which turned up zip . Has anyone done this ?
If so ...on the outlet side of the TB theres a ridge on the inside about a half inch from the flap by the vapor line connection . Would it be ok to flatten that ?
seems like theres a reason for it since it would would flow much better without it . Thanks in advance

 

Shouldn't be a problem as long as it doesn't effect the seal of the butterfly when closed, that would give you idle issues, and most likely codes you couldn't get rid of.

As far as porting and polishing, on the intake side of things, porting can gain you a little, esp if you're trying to squeeze every last HP. Polishing is ok up to and in to the intake, farther than that in the tract, I'm not a fan, the air from the intake to the combustion chamber needs a little turbulence to assist in fuel atomization.

It really just depends on how much time you want to put in to get what will boil down to small "tweak" type results.

 

Thank you for the help. I'm retired so I have lots of time 🙂

 

You obviously are very knowledgeable about minis so if I could get some advice about future mods . I'm all about quickness....0 to 60 in a hurry us what I enjoy. Given that ,what other recommendations could you give me . I plan on making a better IC diverter and possible getting meth injection ,a tune,and lighter rims

 

Instead of hijacking this thread, send me a PM and I'd be happy to share what I can, or start a thread and many of us will help.

EDIT:
Ok, I'm apparently not paying attention, completely spaced in the fact that this was your thread.
My apologies...
Don't know where my head was.

Either ask away or again PM. but let me give you a good starter thread to help you with some possible particular questions.

https://www.northamericanmotoring.co...nded-mods.html

 

They sell fully ported and polished intakes for the R53 for very cheap..cheap enough to justify spending it and saving the time and effort
I found making the Cai a true one by modding the wall behind it and adding a oversized intercooler dropped intake temps in summer an avg of 25 degrees..I got the largest intercooler not the gp and I love the setup and it cools down very quick and even on the hottest days and hardest runs I don't see intake temps above 200 degree F

 

Thanks miniman I did the same CAI mod I also ran a 2in hose from the fog light opening to the air box . As far as port and polish I love doing things like that myself

 

I hear ya..I am the same way..

 

Do your homework on the intercooler design, before you spend a bunch of money. Pick up a physics book at your local library, take a gander at the airflow section.
JUST...cooler temperatures is only part the deal.

So far as I've seen only ONE aftermarket intercooler that has added any sort of flow straightener into their intercoolers.
As the air enters the tubes of the factory cooler, they added a device that helps smooth or direct the flow into the tubes. Most aftermarket DID NOT spend the time or effort to add flow straighteners.
So...what happens, as the air enters the tubes on a stock cooler, it is "smoothly" directed into the tubes to be cooled. Most aftermarket coolers, have 90° walls that the air hits and is disturbed, then has to force it's way into the tubes. the faster the air moves TO the cooler, the worse the air is stacked up before entering the tubes.

Can you imagine an airplane with the leading edge of the wings having square surfaces..?! Same thing..!

So, in reality, cool temperatures are about 1/3 of the equation, "smooth" airflow is about 2/3 of the equation to make good power.

The smart bet is to either stay with the OEM cooler, or go with the GP intercooler.

Mike