Sparco bar issues. 56k beware

[peak]

Thanks to all for the input!

The car is a very early euro import. It's VIN is WBAAK010X00842046 making it the 46th non-cat euro made. After looking at the ETK I found my plenum has a different part number.

An oil separator is generally considered a good idea because without it your intake sees more oil than it normally should. This can lead to a reduction in octane rating and increase your chances of detonation.

This has me very concerned because I have my first track day(s) with the car this weekend. It may also explain why the engine was replace after only 60k!

It looks like the elbow may possibly be a screw in part (when I got to work, I popped the hood and took another look and I saw a seam). So, I'll see if I can get a pipe wrench on it to get it off. If it is part of the plenum casting. It will need to be cut. See pic. This is where I would cut.



After cutting, proper sealing would be critical to maintain the proper A/F ratio (not introduce any leaks...AFM setup). I'm not quite sure how I would seal it properly (temporarily). On the breather side, I would add a catch tank with a manual drain for right now. My freind with my old race kart also has my old catch tank on the kart. I could borrow it for the weekend.

Procrastination strikes again. I should have taken care of getting ready for this weekend's track time weeks ago. When I raced bikes and karts there was always something that came up at the last second. It's not a good feeling going out on the track while worrying about your equipment!!!!

Thanks again,

Damon in STL

[Stan]

I wouldn't cut the plenum - that thing is rare. Get a US plenum or mod the bar or whatever.

Stan

[AlpineRunner]

I have to admit I don't really understand what this hose is for or the consequences of cutting/sealing it, but what about just crimping the hose? It sounds like it will have the same effect

[Erik_Brannfors]

I love these cars! Isn't it simply amazing how the term "homologation special" really does apply to these cars? After all the time we spend under the hood, under each others hoods, browsing the ETK, scanning thousands of pictures on the 'net and from other members that something like this comes along and smacks us up side the head.

Don't cut or modify the plenum that you have. Try to find another plenum to replace yours with. Someone on this board must have one in usable shape for you to replace yours with. This example of such an early production design should be at the minimum swapped out and stored, and rightfully should be left in place and lauded over. Your car is one unique setup.

That said, I don't have a plenum for you. Sorry. But it's nice to be caught off gaurd by these cars from time to time....

[peak]

I wouldn't cut the plenum - that thing is rare. Get a US plenum or mod the bar or whatever.

Stan

Okay, how much would you be willing to pay for a "Rare Early Euro" plenum? If everyone thinks I should save this one let me know. If it gets put on the shelf.....it more than likely will never be used again. Using the key words "Rare Early Euro" should attract some attention on ebay!

I would need a plenum and gasket by mid-day Friday. Anyone have one I could borrow/buy?

Damon in STL

[peak]

I just looked at this link and all of the plenums have a port in the same general location as my plenum.

Valve Cover Finish

Can someone tell me the size of that port on the US plenum?

TIA

Damon in STL

[UNHCLL]

I'm guessing you've driven the car for a while as is correct? In that case... I wouldnt rush to "fix" this issue before your track day. Just leave the Sparco off and drive it as is. You wont gain/loose any serious handling by leaving off the sparco.

Once the HPDE is over, then you can decide what is the best course of action and how to best impliment it.

$.02

Good luck,

[Jake]

Originally posted by peak
I just looked at this link and all of the plenums have a port in the same general location as my plenum.

I'll try to get a picture of a typical plenum for you later tonight. Normally, where yours has a port, others are cast without a port. There is a stud that hangs off in the same position and its job is only to carry an Adel clamp for the brake booster hose. That's actually what you see in the other pics; it's not part of the breather hose.

The breather hose actually takes a 90deg bend straight down and then forward to meet the oil separator under the throttle bodies. Some of the pictures in that thread are a bit deceiving.

As far as replacing it before your event, I wouldn't think it's absolutely necessary. I would eventually, but I wouldn't lose sleep over it. Assuming AFR is in check and you're not pumping blue smoke out the exhaust I wouldn't sweat it.

It is rare and would be interesting to own but I'm not sure what one would be worth. Sounds like a job for Ebay!

Cheers,
Jake Larsen

[Jake]

Originally posted by AlpineRunner
I have to admit I don't really understand what this hose is for or the consequences of cutting/sealing it, but what about just crimping the hose? It sounds like it will have the same effect

You need some sort of relief for crank case venting. Some gases make it past the rings and without relief, pressure would build and find the weakest point to escape.

If you blocked/crimped off the breather hose it would probably pop out the crank seal lips or your dip stick. Or I suppose another option is the distributor seal. Either way it wouldn't be a happy engine barf'n oil out from every available orifice.

Jimmy P made some good points a few weeks (or was it months?) ago about his preference to use a catch tank. With your crank case vented to your intake you benefit from a little negative crank case pressure as the intake will do more sucking than what’s expelled past the piston rings.

Negative crank case pressure is a good thing from what I understand as it reduces pumping losses. But Jimmy pointed out that oil mist ingestion reduces octane rating and after I thought about it a bit, it seems this would actually be more important; at least for the majority of us.

The only issue with using just a catch tank (and not venting it to the intake) is that it may be illegal in some states. Another reason manufacturers vent the crank case to the intake is that it allows the engine to reburn those exhaust gases. Venting it to the atmosphere isn't very 'green' to those environmental types.

Take care,
Jake Larsen

[AlpineRunner]

perfect explanation Jake, thanks!!

[Low Level]

-Bumping an old thread-

I just installed a Sparco strut brace on my June '87-built M3. It slipped right on perfectly, no problems. No issues with length or spacing between the strut towers. Phew

However, I've only got about 1/4" between the installed brace and the small nut/bolt on the back of the intake plenum.

Sure enough, when I started the car, there was some new vibration present. I checked under the hood, and the nut/bolt had already started rubbing against the brace, shaving tiny flakes of paint off of it. The brace was installed tightly, so it wasn't loose.

So I pulled the bar off the car, and the extra vibration is gone.

Is my motor sagging towards the back of the car, somehow? Maybe due to old engine mounts? I believe I have original mounts on the car... I know the tranny mounts are definitely old, as I had a close look at the underside of the car yesterday.

Any tips?

[Dominic]

AJ,
I think you're definitely on the right track to look at the motor and tranny mounts. I doubt that I have much more than 1/4" clearance between my strut bar and that nut, but I don't have any rubbing there. I'm currently running IE poly motor mounts and the Bimmerworld "upgraded" trans mounts.

Good luck.

[Low Level]

AJ,
I think you're definitely on the right track to look at the motor and tranny mounts. I doubt that I have much more than 1/4" clearance between my strut bar and that nut, but I don't have any rubbing there. I'm currently running IE poly motor mounts and the Bimmerworld "upgraded" trans mounts.

Good luck.

Thanks for the reply!

Yeah - it has to be. I can't think of what else would cause the bar and the bolt/nut to get so close.

How is the NVH with the poly motor mounts and solid rubber tranny mounts?

What hardness are your IE mounts?

Thanks again,

[Dominic]

I think it's tough to describe NVH but I can say that I don't mind it. I really didn't notice a huge difference in NVH vs. the stock mounts, but then again my passenger side mount was completely disintegrated so it was just left to metal on metal rubbing...

I daily drive my car, but I also have fixed shell seats and a roll bar installed. Regarding the hardness, I'm not sure. I think IE only sells one type. I bought mine from Bimmerworld. Mine are yellow if that helps. When you change your mounts double check to make sure you have a heat shield between the mount and exhaust header. I have pictures in a thread somewhere here of the first poly mount I bought that melted because I didn't have the heat shield installed!

If it turns out that you need one I actually have an extra lying around somewhere that I could sell.

[paintpro21]

AJ

I just removed the bolt and stud from the back as it was just a support point for that hose. The hose just rests under the bar now.