whats wrong with the OEM O2 housing?

 

Cold air is more dense so you will see some crazy boost characteristics. I always turn my boost down a few pounds in the winter as a "just in case" scenario.

You need to make the O2 housing wastegate side big enough to put a golf ball through. It is a pain to do, but it works great once it is done.

Easiest way is to remove the DP bolts then pull the turbo and exhaust mani as one piece. Yes it can be done with the radiator still in the car.

Another way is to remove the clamp that hold on the hot side. Then you can remove the hotside with the o2 housing still attached. Be careful of the tiny dowel pin that aligns the turbo....it breaks easily. good thing about this way is that you can port the hot side while you are at it.

Or you remove the 02 housing with the turbo still in the car but it is a major pain to remove and reinstall.

Let me know if you need a hand. My garage is always available.

Heck drop some $$ on a fuel pump....I can install it in about 15 minutes.

 

Thanks for the info on the different removal procedures. Not sure how I want to attack this but I am 99% sure the issue will go away after I open that merge up.When I installed the o2 it was a pain since I did it with the turbo still on the car and had to remove the radiator.

I've got a garage but thanks for the offer. I wouldn't mind some help/company while doing this though. Also, I am not sure that I have sufficient grinding capability with my tools to get this one done.

The pump is an option but not at this time. I know its such an easy job but there is a good reason.

Mark - Actually, I have seen some debates on this subject whether the o2 is a worthwhile upgrade over the oem. Some say yes, some say no. If I knew about this, I would have either ported the thing before install or not installed it at all. This cold weather business sucks.

 

Maybe think about picking up another 02 housing and porting it. Then when you get more time do the install. Then port and sell the used one.

 

The OEM 02 housing is a bit restrictive. It is fine for stock turbos and stock cams that will not go on higher boost. Once you upgrade to cams the flow will be restricted by the O2 housing. The tubular O2 hosing frees up some HP and allows for slightly better spool. Buschur has done dyno tests that show the 02 housing is good for about 15 whp.

 

Im free saturday, and have a drill bit specifically for grinding/porting, it made quick work of aluminum, I believe it will work on cast steel as well. do you have a vice? it makes the job a helluva lot easier.

I NEED EVERYONES PHONE NUMBERS AGAIN>please.

 

I don't see how boost creep is possible with a Megan O2 housing. The volume of the wastegate portion is easily double that of the stock piece. I think you are just experiencing winter creep like Paul stated. Once the temps start to dip into the 40s and below you need to turn your boost down if you are on a MBC or EBC. My EBC is in my glove box and I just reach over and keep turning it down until it sits where I want it.

Do you have a stock DP and cat or something?

I agree with Paul, pop in a fuel pump. The 15 mins you spend will be mostly spent taking out the seat and putting it back in, the actual fuel pump install takes about 30 seconds. I would find the $80 or whatever they cost long before I would spend all that time removing the O2 housing to port something that may or may not fix your issue.

 

I experienced huge boost creep when i got my 02 housing....I guess some are better than others. Hogging it out is just good insurance.

The cold weather does affect us all though.

I think I am going to try playing with ECU controlled psi based boost control. The I won't have to worry about the weather affecting the boost curve as much. I will use my Zeitronix map sensor and the stock boost solonoid (pay upgrade to a GM 3 port). The stock ECU is capable of load based and psi based boost control and you can tune it independantly for each gear. Pretty amazing stuff.

Oh and if any of you are having cold start/cold idle issues.....I worked very hard in the EcuFlash forums to solve the problem. Get with me if you want me to fix you up.

I love this tuning stuff.....I am getting quite good at it....lol toot, toot....yes I tooted my own horn.

 

my car barely turns over when it's sitting for a few hours in anything under 15-20 degrees or so. Paul, if I'm around this winter I'll probably pick at ya for advice... but for now she's just sitting still. and **** do I miss her so ****ing much..... it's been almost 2 months now.

Coming home for Christmas, I'm literally going to put 500 miles on my car for the 5 days I'm home.... and probably never drive more than 30 miles from my house.

 

If you put in a small battery (oddyssey pc680) it is only goor for a couple years of daily driving and cold starting. I resommend a new battery. If you car is going to sit for long periods of time....disconnect the battery and keep it on a tender and keep it off of the ground.

 

i turned my boost down a few weeks ago, and it is now about 2 pounds more at full throttle because of the cold weather.

 

MBC's are notorious for having higher boost in the winter. My AVC-R is much better at holding my desired boost. I really don't need to switch to ECU controlled boost, but it is my next step in fully understanding ECU tuning. Once I have boost control down, I will be ready to start tuning other peoples cars and have potential beyond my current ability.

 

Paul - Good idea on getting a second housingand prepping it for minimal downtime. I don't mind the downtime though, since the car is going to be garage-queened for a while with the recent weather.

Nick - The Megan o2 may have a larger o2 side but there is still restriction. And I have a full 3" turboback with TP. So its open.

I went to the extent of cleaning out the MBC which looked fine anyways (all it is is a ball and spring). I installed it with minimal spring force and saw sub 20 peak until the high end at which it went to about 24psi. I also did a boost leak test. After this, I knew something was up since I have never had this issue until installing the o2.

Based on what I found on multiple threads, it is a very common issue. Here are just a few with a quick search...
o2 housings suck in cold weather
Boost creep fix

If there is anything else to check I am open to suggestions but I don't think cold weather alone is causing this issue. It isn't a matter of a couple pounds off. I could remove the MBC and run off the wastegate alone and it will still spike by 7000.

I would throw the pump in right away but shouldn't be needed at 22psi.

 

Very good advice Paul. I have seen a lot of people make these mistakes...

Actually there are a ton of threads on the mini-batteries with cold weather and failure. They are good batteries but you must understand how to treat them and accept their lifespans.

 

I've been turning wrenches for the majority of my life. I know a thing or two about working on cars. Not to mention I am a Maintanance Shop Chief in the Army.

I just wish I had the fundage to start my own shop. I have all of the skills necessary but location and money I lack.