I'm new to owning an EVO but I've done work on them and read quite a bit about them over the years. I have 7 years of 4g63 turbo experience and have owned a plethora of turbo mitsu's, so I'm pretty good at diagnosing and chasing down potential problems. Since I've started searching the EVOM forums I've found myself slightly discouraged. Either I've yet to figure out how to use the search function here or this place is worse than DSMtuners when it comes to mis-information and the spread of hearsay..

I have a few minor questions that i can't seem to clear up.

I have a 2003 EVO, the mods consist of:
Apexi air filter
crushed 1G BOV
AMS boost controller
Taipan XP turbo back exhaust w/high flow cat
Samco IC couplers
ACT clutch
Fidanza aluminum flywheel
SS brake and clutch lines
MR boost, oil temp, volt gauge set.


First of all, is it a common problem for the oil temp sending unit that goes into the oil drain plug to leak? Mine doesnt leak very much but it's enough to leave drops of oil on my garage floor and it's begining to annoy me. is there a fix for this?

2003 Evo LSD's..?
I've read 03's came with rear LSD, i've read that they came with front LSD, i've read it's only the later RS model that came with front, I havent put the vehicle on the lift since i started wondering so i havent checked it out, but can anyone point me in the direction of some factual information?

Boost, fuel cut and ecu flashes?
with an apexi filter kit, still retaining the factory intake tube, is it reccomended to get a flash, i plan to anyhow but im concerned with the safety of the engine after reading horror stories of lean situations with intakes installed. I cant imagine a cone filter affecting anything but i'd rather be safe than sorry.

Prior to my BOV and filter upgrade, the vehicle ran 1.35 bar (19psi) and tapered off as it should, after the bov and intake upgrade, the vehicle ran 1 bar unless i throttled it in a higher gear, then it creeped to 1.5 bar and hit fuel cut. My first notion would have been that the stock BOV sucks... but that doesnt account for the low boost levels during WOT while rowing through the gears. It only accounts for the 1.5 bar action when starting from a lower rpm in 3rd, 4th or 5th and going WOT towards redline.
Suggetions?

Please if you post information, cite where you got it from if you can... if i hear much more 'i think' or 'i heard' im going to start bashing my head against the wall.


thanks!
-Josh

 

ill confirm a few things.... 03 did NOT have front LSD.... i believe only RS had front LS in the early USDM evo days and they came out 04 i believe. i cant comment about the oil sender leak. the 03-05 plastic nonMR bov's do suck bad, get aftermarket or the MR/JDM/2006 metal bov. yes intake requires a flash/tune.

 

Oops! I guess I left out the 'i believes' as well.

The plastic BOV's do indeed suck but the early metal mitsubishi BOV's (circa 1987-1994) are great at holding up to 25psi. I would grab an MR bov if they were cheap and readily available, but i chose the early metal one because of it's availability.

You say 'yes intake requires flash/tune' Does that mean simply a cone filter requires a tune? or are you just repeating that the addition of an aftermarket intake tube (hks/dejon/ect) requires a reflash/tune?

These repsonses are exactly what I was talking about in comparison of evom to dsmtuners...

 

There's no way for the oil to leak from where you're describing. It's either coming from around the plug or somewhere else. Make sure you use a new drain plug gasket everytime you change the oil.

 

The wire and sensor that go through the drain plug, into the oil pan can't leak?

Why can i spin the oil drain plug and hold the sensor stationary? that alone tells me that the sensor isnt fixed to the plug. Please explain how it's impossible for it to leak there? What am I missing?

 

They don't go through the drain plug; they are attached to the end. The plug itself is solid. There's no way for oil to go through the plug and out the other end of it.

 

+1 on drain crush washer for leak

As far as flash / tuning goes. It is strongly recommended that you get tuned if you modify your Evo at all. The stock calibration is pretty poor to begin with and when you put mods on the car it worsens, especially if you have an intake. There is tons of info on this topic all over this board. The ECU Flash forum is the place to get correct info on ECU Flashing / tuning.

Have you checked for boost leaks?

 

If your fuel trims are more than 10% off with the open element filter then yes you will need to be flashed, also the filter will more than likely throw off load in the ecu.
Don't start bashing your head against the wall just yet...just like any forum you have to take every thing with a grain of salt & decide what info is real & what is bullsh!t

 

well dropin air filter u dont need to retune but cone filter? yes you do. im selling a metal bov myself but guess price isnt cheap (just average).

yeah unlike dsmtuners on evom, the trend is SEARCH. u wont get a highly detailed response you seek right away, you'll have to actively seek out the real technical guys on this site (ill give you examples, MalibuJack or Warrtalon)

 

Alright, thanks guys. I'll put the stock airbox back in until i flash the car. I've used the hell out of the search feature, i can't seem to figure out how to narrow things down, +word and -word don't seem to do anything and "word" seems pointless. Is there certain methods im missing?

On the oil leak. I put on a fresh gasket when i did my last oil change, i'll have to look into it more this time around.


How much do you want for the MR bov? PM me if you want to...

 

The tune will be beneficial across the board.
Changing from a K&N with stock snorkel pipe, to a K&N and 4" intake required some changes to the tune on my car.

Alot of the VERY specific answers you seek are in the ECU FLASH forum. If you want to skip past the general kinda/maybe/I dunno answers look there first.

 

If I was starting over I would have gotten a way to log accurate boost (zeitronix or jdm map sensor), a wideband, a tactrix cable and evoscan before I even put mods on. Being able to see what the engine is actually doing will cut through a lot of the crap you come across.

When I switched to a cone filter I didn't need to change my tune at all. It wasn't until I replaced the stock plastic intake pipe with a metal one that threw things off. Rescaling the MAF and raising the lower airflow values in the ROM fixed it.

I'm not sure on your boost problem.. maybe more info would help..

 

^
I absolutely agree with this.

 

This car will remain a daily driver so i do not intend to modify it much outside of it's stock parameters. I have a cable and intend to do some logging soon.

On the topic of boost.. there really isnt much more information I have. If I were to turn out onto a road in first gear and go open throttle to redline, shift to second gear and continue on, the boost will stay at 1 bar. If I am rolling at 35mph and i put it in 4th gear and go open throttle, the boost will start to climb and go past 1 bar, slowly to 1.5 bar around 5000rpm and then fuel cut comes into play. I'll mess with it a little over the weekend and see if i cant figure it out.

-Josh

 

I have the same phenominon with boost but it is not nearly as much seperation. I'm about 1.25-1.3 bar 1-3, 1.4-1.45 bar 4-5.

Simple hallman mbc.

Higher load in higher gears = more boost. But typically not with that much variation in my experience.

Even with the stock turbo it was about the same.