LITE SPD

iTrader: (2)

New to the forum and all I can say is good things about this place. Lots of info and advice. I happen to sell Mitsubishi and Subaru and I am very proud that there is such a following for the EVO. I ended up just selling my brother a 2005 Evolution a few days ago. I pulled him out of a 2004 G35 coupe M6. Nice car, but it does not have the performance of an EVO. He was close to dumping alot of money into that Infiniti, but he wised up and traded it in (he was also losing to SRT4s and that rubbed him the wrong way).
Anyways I have done some searching for him on this forum on finding some power mods. We also want to keep the car looking, driving,and sounding stock too. I know first hand on how Mitsubishi service departments are. I see that the 05 stock turbo has a bigger exhaust side than the previous models. So I guess we will be leaving that alone. But what about the o2 housing, does it need porting when you want to do a 3" downpipe? Is there porting in the exhaust manifold that could be done? Who can do this? Other things we plan on doing is a turboback with high flow cat. We have made a decision on the catback (RSR exmag), but the downpipe and cat we have not decided on yet. I don't know if we should go with a stage colder spark plug or if the fuel system needs upgrading to push the stock turbo? We don't plan on cams for a little while but I have heard some of you going with some fuel system upgrade (fuel pump or injectors) with just bolt ons. I would appreciate some with some of these questions. I've done some searching but could not find direct answers. Thanks for having me on the board .

LITE SPD

iTrader: (2)

29 views and not one response, maybe this board is not so nice.

dridge11

iTrader: (11)

I'm too stoopid to respond. You're questions are much more advanced than my EVO knowledge at this point. I'm a new owner too.

Warrtalon

iTrader: (6)

As is often the case, people claim to search, but they most likely do a cursory search without adjusting the search parameters, because the questions always end up being something that has been discussed many, many, MANY times. Here goes:

1) o2 housing - don't need to upgrade it just to run a 3" downpipe. It's something you can do or not do, but it won't make a big difference either way. There are ported, larger replacement units, and you can just port the stocker if you prefer.
2) Exhaust housing - don't really need it with the mods you are planning, but you can either go with a tubular manifold or port the stocker. I would assume that anyone who does port work could port it for you. You can look in the vendor forum for specifics.
3) TBE is the best mod, but with a HF cat, you will be missing 10-15whp. Any reason you chose the RSR cat-back? You can get the full 3" TBE (catless) for $550-$600.
4) Stock heat range on the plugs is 7, and this is fine for up to 330-350whp. You won't need a range colder until you're around 350whp or if you seriously crank up the boost on race gas for whatever reason. Good stock replacements are the NGK BPR7ES, which sometimes work well even if the stock Iridium 7s start to blow out the spark or get fouled. The copper NGK BPR7ES won't last very long, though, so keep a set handy at all times (very cheap).
5) Don't need to upgrade the fuel system unless you upgrade the turbo, but doing the fuel pump (Walbro 255lph) is still a good idea if you plan on pushing any extra boost beyond 21psi (recommended max on pump gas). It's still not necessary, but at <$100 and easy to install, it's a good thing to do. Injectors are 100% not necessary on the stock turbo.

LITE SPD

iTrader: (2)

Is 21psi the max boost on pump gas for these cars? If so then we would only be turning the boost up 1psi from stock. Or did I misunderstand you?

Warrtalon

iTrader: (6)

Yes.

You understood me. The MBC or EBC you choose will not just raise the peak boost, but it will also go a long way towards eliminating the factor ECU-controlled taper that goes down to 16psi in a hurry. You will hold 20-21 psi to around 7000 before it tapers down to 18 or so. This is much better than the stock spike to 20.3 and then immediate taper to 17...

Sgt Blamo

iTrader: (1)

Warrtalon,
Question, you referenced this mod " 3) TBE is the best mod, but with a HF cat, you will be missing 10-15whp. Any reason you chose the RSR cat-back? You can get the full 3" TBE (catless) for $550-$600. " Are you recommending a catless exhaust, and if so, does that void the warranty? I'm picking up my 05 Evo VIII later today, so I've not seen the warranty yet. What particuler brand do you recommend @ the $550-600 range, as that sounds very reasonable to me. I'm looking for an exhaust that will give added performance and have a deeper, musculer sound. I hate those coffee can weedeater sounding cars!
I'm new to the Evo world , so any tips you want to give would be greatly appriciated.
PS. I did do some searching, taht's how I found this thread. I will continue to do same.

Warrtalon

iTrader: (6)

You can get the catless 3" Megan TBE for $550 from Zeus. An exhaust can't just cause your whole warranty to be voided, but Mitsu dealers will normally frown upon it if you touch anything other than the cat-back. Even if you go with a HFC and downpipe, that's just as bad to them as going catless. So, you either stick with a cat-back or go catless. You do a HFC if you want as much performance as you can get without being completely illegal and not passing emissions.