3-Series (E21, E30)Chat relating to the BMW 3-Series from 1975-1983 and 1984-1991 line. Specific models: BMW 315, BMW 316, BMW 318, BMW 318i, BMW 320/4, BMW 320i, BMW 320/6, BMW 323i, BMW 320i. E30 Family models include: BMW 325e, BMW 325i, BMW 325is, BMW 325ix.
Hello all, back many months ago i posted(my initial posts actually) that i had started a turbo build on a 86 325e.
Well after many months of hell, the car is running, and strong for the most part, however i need some help from those who have done this sort of thing.
I was having blow by issues with the crankcase pressurizing. The breather line that goes bwtn the valve cover and the throttle body kept coming off, so i plugged the TB bosse and installed a catch can that would safely vent the crankcase to the atmosphere, without theoretically causing any vaccum leaks.
Well with the hoses clamped on tight and set up so the V/C vents through the catch can and out, i have stupid amounts of smoke existing the exhaust, to the point where i couldnt see cars behind me.....ok so what do i do?
I went to a gas station, pulled the clamp off the hose going to the valve cover and took the breater hose off, essentially creating a huge vaccum leak and allowing the crank case to vent to atmoshere while under boost.
Well i did this and it runs great, pulls stronger than with the car running through the catch can....this makes no sense to me.
As well, when the car came back to me originally a few days ago, i saw that breather line had slipped off the valve cover, telling me that the crankcase was still pressurizing under boost. I slid the line back on, played with the AFM adjustment and cold start injector and all was good.
Now my concern is this. Tomorrow morning when my buddy goes to start the car in the morning, breather line off, im *assuming* the car is gonna idle poorly and initally run like shit, but it will not smoke. The alternative to hook the line up and and create smoke screens all day.....
I dont know what to do.... if anyone knows what could be the potential problem, pls post up and help a fellow euro tuner.
Nice e30, I dont have an answer to your question, but I do have a question, now is the 2.7eta motor beter for turbocharging than the 2.5i motor? I know that the compression ratio is higher on the I, but which one will end up getting more power? Did you have to change your head, or cam, or put bigger valves? Ported out?
By the way your car is awesome!
__________________ If you show your BMW love, she will love you in return.
I dont understand why your crankcase would be pressureized anyways? Wouldnt that mean that your rings would be going bad? On the turbo charged 240sx I had it just had a filter on the crankcase breather hose.
I dont know much about turbocharged engines but maybe that will give ya an idea.
The wheels are made by Fittipaldi and are now discontinued. I will try and find the model of wheel for ya, if i still can. They are a 17x7, 40mm offset if i remember correctly. Got the wheels from a buddy of mine who got them from a place in my home town here. I paid 1800cdn for them.
Thx for the compliments. Im not too sure which engine if better for turbocharging. You definately have more RPM's to play with in the IS engines, but the 9:1 compression ETA engine mated to a 3.73 LSD and short shift responds quite nicely to the boost. At 5psi the gains are very noticable. The torque is crazy. hehe. Im quite pleased when the car is running right. Compression on the M20 is 8.8:1 where the ETA as i stated before is 9:1. No i did not change the cams or port the head. The motor hasnt been cracked open yet, but when it does, its getting a 3.0L stroker engine. I still need to find info on it, but the ETA isnt going back in.
info on the wheels is above. Did not have to do any suspension mods to get the wheels to clear. Tires on the car are P205/40R17 kuhmo 712's. they dont rub and fitment isnt an issue. Suspension mods include Suspension Tec 1.5" drop, front/rear Sparco Sway bars. New shocks are on the way very shortly, once the engine is running up to par.
Like yourself i could not figure out why the CC was pressurizing until i talked to one of the members of Maxbimmer and it made a lot of sense. on the ETA and M20 engines, there is a vac tube that goes from the underside of the intake manifold to the oil pan. Well once the turbo comes online and the engine see boost pressure, the engine cant cycle out the pressure that is being caused by the engine, cuz the bottom end of the motor is now seeing boost, via that tube and what is happening is the breather hose on the valve cover is either shooting off and causing the car to stumble or staying on and blowing all the oil through the valves, right through to the exhaust. To counteract this prob, one must take that pipe out, plug the underside of the intake manifold, then drill and weld a T junction and, so the oil pan can still breather and run it to the compressor side of the turbo(bwtn the air filter and compressor wheel) so the bottom end can see the little bit of vaccum that it needs. Once doing this mod, the car may still smoke a little bit, but nothing to the extent to what it was and then the crank case should no longer pressurize.
Originally posted by pogiboy9@Feb 10 2004, 06:17 PM Does That lead to a cold air intake? or does the turbo lead to that pipe under and go to the intake manifold, whats that Filter for
that air filter is there to suck in fresh filtered air for the turbo to mix with the hot exhaust gas, when is then fed through the pipes via the intercooler, through the AFM and into the intake manifold.
ya what that guy said and where did you get it what did it cost
__________________ <img src='http://bmwforums.penguinstudios.com/BimmerKris/salesig%20copy.jpg' border='0' alt='user posted image' />
<a href='http://www.acantha.ca' target='_blank'>www.acantha.ca</a> 100% thrash your face off metal
The AutoGuide.com network consists of the largest network of enthusiast-owned enthusiast-operated automotive communities.
AutoGuide.com provides the latest car reviews, auto show coverage, new car prices, and automotive news. The AutoGuide network operates more than 100 automotive forums where our users consult peers for shopping information and advice, and share opinions as a community.