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Build Thread?


GunMetalGrey

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For those of you that are not on facebook
Last night I loaded  up a modified tune from our lovely Mr. Snap and went for a drive having done some motor work the other day, including sealing the compressor housing to the turbo (it had a huge leak) I drove around for a while staying out of boost and enjoying he non hunting idle and the greatly increased driveability. My new bypass valves were working great and everything felt great about the car. I was happier than I have been in a while, knowing that a few settings were holding me back from having a car that was great. Towards the end of my drive I decided to get into boost a bit to see how it felt with the updated settings, I rolled on the throttle a little bit and the car sucked to the ground and just started going like a bat out of hell. I couldn't believe how much difference a tune could make! I let off quickly due to being in a slightly residential area and rolled over to a better street for playing. I turned onto the street and cruised to second gear (which the ecu now recognizes from VSS input and RPM) and rolled on the gas again, the turbo spooled and hit like a freight train, tires spun and I rocketed forward. Wow. This was amazing. I short shifted into third and gave it some more gas, at a 45 roll the rear tires lit up like a christmas tree and it once again launched forward. Something was wrong, something didn't seem right. The turbo had never screamed like it did those last two gears like it ever has, the bypass valves were never that loud. I tapped the peak button on my boost gauge to show the highest recorded boost pressure. It showed 20psi. Shit. When I put the face of the turbo back on I completely forgot to put the wastegate vacuum line back on. Then the car started to run weird, it was missing, it was hanging on rpms after shifts. I rolled back over to the shop and started being not too happy. I had looked at setting overboost protection in Megasquirt the day before, and did, but when I loaded the new tune it wasn't on there and I forgot to go back and enable it, I didn't have my boost gauge set up to warn me when I went over 10psi... Damn. Not good. 
I pulled plugs and saw extremely obvious signs of some detonation on the pistons, but it didn't look too terrible. The plugs looked a little bit worse than they did the day before when I checked them. I started it back  up again and it seemed to be okay, but the expansion tank on the radiator was REALLY bulged. I hooked the boost leak tester back up to it for kicks and instead of leaking all of the air out of the seal between the compressor housing and the CHRA it just went no where. I couldn't hear the air escape, but it wasn't holding pressure. I waited a second and heard a nice "blub blub blub" coming from the engine... damn again. The headgasket wasn't sealing. I don't think this was brought on by the overboost though. I had issues with coolant dissapearing and doing other weird things earlier so I am uncertain if it just wasn't sealing right the whole time. 
The biggest question I have now is, what to do? If I need to get the head decked I will have to take the motor 100% apart again, which means new bolts and bearings in the bottom end, which would cost a fair chunk of change. 
If I find an m52 (motor I want anyway) I would spend that money towards getting it rebuilt, and throw a set of rods and pistons in it for a long term motor that could handle many much powers. 
I am pulling the motor tonight to asses the situation. 

TL;DR? 
cliffs
New tune rocks

PSHHHHHHHHHHHH
SqUALLLLL
HOLY CRAP! 
Oh Crap!
Shit
Damn
blub blub blub
Crap

10941522_10204605192425306_2875309541917
 

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Im so glad to have you join me in the accidental overboost club. We have great activities lined up this year such as "name that random engine fragment" and "how to self ventilate an engine block".

Why would you need bottom end hardware from a head gasket job?

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A lot of people have issues with the gaskets sealing (not too surprising) and most people that have the block decked don't have issues. 
I used copper spray, and torqued it all down, so I am slightly unsure why it was leaking.
Cut ring isn't something I am too familiar with, am I able to drop my compression with one still?
Edit: just looked at them again, I wish they specified a thickness on the spacer. It is an interesting idea, and may be a good solution. 
Edit Edit: Thickness is the same as my current MLS, the torquing of the head with the copper spacer takes 3+ days, but does make sense. I am thinking that this is a very good route to go. 

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Pulled the cams out last night to see how loose the headstuds were. Each nut took kat least another 1/4 turn to get to their torque spec. Going to see if that was the issue! 
The cooling system held a lot of pressure overnight, and was still overflowing when I took the expansion tank cap off, so the gasket seals well enough for that. As stated, going to test the re-torqued head. 

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All that can go wrong will...
I retorqued the head and got it all back together last night. I hooked up the boost leak tester and still had bubbling. It still sounded odd though, so we spent some time tracking it down. It was oil bubbling, at the bottom of the oil pan. Took the oil feed line off of the turbo and it was shooting air out of the oil inlet. Wtf. Pulled the oil drain line off of the turbo and that was pushing a ton of air out. Double wtf. With the oil drain line disconnected the bubbling stopped. 
So the turbo is toast... cool.
This wouldn't be so bad if it didn't have a slightly bent compressor fin from when I got it, so I am not going to spend the money to rebuild a turbo with a bent compressor blade. This would mean getting  a new compressor wheel (billet most likely) and sending it out to get it rebuilt and balanced and cleaned etc. This quickly gets to over $500 in costs, but would result in an upgraded turbo. 
A new HX35 is $800, a Garrett would be around $1200, but going with a different turbo means getting my exhaust modified, which would take even more time. I need to make some calls today to figure out what I am going to do. 
The frustration continues ;)

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new borgs are around 600$ shipped to your door. 

But anyways, a rebuild is dirt cheap and you can do it yourself( about 60$) and a new comp wheel should be like 400$ but they are EPIC. 

about 500$ later you have a 700+whp turbo without modifying anything id say thats a decent deal. or buy a borg and modify your exhaust. 

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new borgs are around 600$ shipped to your door. 

But anyways, a rebuild is dirt cheap and you can do it yourself( about 60$) and a new comp wheel should be like 400$ but they are EPIC. 

about 500$ later you have a 700+whp turbo without modifying anything id say thats a decent deal. or buy a borg and modify your exhaust. 

Is EPIC some fancy term I am unaware of?

Modifying my exhaust is not optimal. I have no Idea as to how long it would take to get that done, and I am already getting constant setbacks! 

I shall look into borg

Edit: what borg warner turbo did you have in mind? The prices I am seeing and your price doesn't line up lol.

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new borgs are around 600$ shipped to your door.

 

Link pls.

 

I couldn't find a good compressor map for the HX35, but assuming that it's somewhere between the HX30 and HX40, it should be a decent match after you turn the boost up. The differences between the HX30 and HX40 compressors isn't as big as you would expect. I suspect the differences between them is on the hot side, either the AR or the exducer size, but I haven't looked into it. I wouldn't do anything fancy with the compressor if it's going to increase flow. You're already in a good place there.

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Most of you insist on putting very small turbos on these things. Look up the average turbo on a 1jz, and add a couple mm's haha. Our heads flow better.

Who needs boost before 4k anyways? Haha.

The billet compressor wheel not only flows more per psi but it helps spool! More importantly transient response. If I was him I would probably buy a stock compressor if I wanted cheap, but he mentioned upgrade, so I figured I would say that the billet wheels for these have been raved about with great success.

I personally would never put anything smaller than an hx40 on a 24v motor.

Sent from my iPhone using Tapatalk

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So the turbo is fine. I had a discussion with a guy who used to work for dodge and now works for G-Pop Shop and he went into full detail of how and why it is leaking the way it is, and that if he sent me a brand new one it would do the exact same thing. 
Simple version, it's the design intent to push air in, but in operating conditions it only sees a tiny bit, which is how it keeps oil from seeping out, it uses a piston ring type seal on the front of it. 
This makes me happy. 

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