Someone money shifted my car today

[jrcook320]

May I have your attention please:


:



That is all, thank you.

[pommeree]

Hey can y'all help enlighten an old dumbass ...
I thought it was the exhaust valves that took it in the kisser when you over-rev.
Aren't they the one's left "floating" at TDC at the end of the exhaust stroke?
If an intake floats, it happens somewhere past BDC, no?
Thanks,

[blitzed310]

What happened?

[jrcook320]

Hey can y'all help enlighten an old dumbass ...
I thought it was the exhaust valves that took it in the kisser when you over-rev.
Aren't they the one's left "floating" at TDC at the end of the exhaust stroke?
If an intake floats, it happens somewhere past BDC, no?
Thanks,

Good point...

I talked to bavarian engine exchange, their engine builder is on vacation and they can't help me right now, but their engine builder that was around in 2000 when I bought my hi po head doesn't work there anymore so they probably can't help me anyway.

I then talked to TEP. The guy said that if I have even compression then it's probably ok, just check for damaged rockers. He thought the only way a valve would seal sometimes is if it was slightly bent and the guide was worn out, but he said I'd have other issues like buring oil if the guide was that bad. I asked him what the likely hood of the motor sustaining 9500 r's unscathed and he said if it was built well then it could be ok. I mentioned I had stiffer valve springs and a 280 cam and he said the valve springs may have saved the motor.

I then talked to Jim at metric mechanic for about 30 minutes over lunch. The guy is incredible, he's forgotten more than I'll ever know. He took the time to listen to specifics about my setup (what head, pistons, crank, cam and valve springs I'm running), what happened, test results, and asked questions about my test methods. He said he doesn't put much stock in a leak down test because the pressure used to do the testing is so much lower than what a motor actually sees and it's also a static test used to test a dynamic system. He was sure that a compression test should show the true health of the motor and thought my numbers actually seemed high, suggesting that my compression ratio was higher than I suspected. He said that a stock e21 2.0L should read about 125-130 psi on a compression test and that he would have expected to see something more in the range of 110 psi because of my larger combustion chamber and my cam. He said that generally speaking on a stock healthy motor you can divide the test pressure by 16 to get your compression ratio (so 130/16=8.1 CR which is correct for the 2.0L), on a motor with mild cam you could divide that number by 14. Since I read 140 psi he thought that my CR was higher than the 7.9:1 that I thought, possibly from carbon buildup or other factors. I mentioned that the head had been decked, but that I don't know how much (it was refaced to remove damage incurred during shipping). He mentioned that decking the head advances cam timing (sounds opposite to me) which would increase the dynamic compression since the valve is going to close sooner.

As for the valves being bent, he said that the intake valve is most susceptable to piston contact at around 7-12 degrees after TDC and that it's not likely. He said that it's more likely the exhaust valve would be bent since it could still be floating as the piston comes up on the exhaust stroke. He talked alot more, mentioned valves bouncing off the seat but the overall concensus was that I should trust the compression test and ignore the inconclusive leak down test. He said it sounded like I had a good setup and that the proof lies in whether or not it works. Since the motor runs well and tested good, it's probably fine.

He also suggested that I start monitoring EGT's because that's the only sure fire way of knowing when I"m at the verge of melting a piston.

BTW, I also asked TEP, Bavauto, and metric Mechanic about rocker retainers. TEP said they could get them but they were special order, Bavauto doesn't carry them, and Metric Mechanic said that they only ever worry about them on a motor that's going to regularly see over 8000 rpm. He said they're not needed for regular 7000 rpm use.

What happen?

Someone set up us the bomb!!!!


jk, I'm still frustrated and angry about the whole ordeal.

[Layne]

I have to agree with you, it looks like milling the head would result in retarded cam timing. I don't presume to know more than this guy, maybe he just got it backwards.

[Greg323i]

Here's an idea from a dumbass: Is there anyway you can compress the valve spring? With the spring compressed the "offending" valve should just stick and not drop down. Having rebuilt the head on my car I know it's not an easy thing to do, but it might help you determine if one or more of the valves is bent.

[epmedia]

I have to agree with you, it looks like milling the head would result in retarded cam timing. I don't presume to know more than this guy, maybe he just got it backwards.

Backwards, Yes: The valve-train turns the same direction as the crank-shaft (duh). The chain tensioner is on the outboard-side of the engine (duh). If the head is milled-down, it will retard the timing of the cam a-tad. (looser chain on the "pull-side" - however not loose because of the tensioner).

Thicker head gaskets are avail as well, for when a head is milled...

EDIT: Tough call on the "bent-valves"... All you do is fill the head chamber with a light solvent and look inside the ports for leakage. Let the solvent sit all day for your final determination of a leaky/bent valve. Also, may even be obvious signs of physical damage on a valve (piston hittting valve)...

I adjust my valves .008-.010 to give space for carbon-build-up - and then hot-rodding.... till I know for sure that the valves are clean.....

Robert

[jrcook320]

Backwards, Yes: The valve-train turns the same direction as the crank-shaft (duh). The chain tensioner is on the outboard-side of the engine (duh). If the head is milled-down, it will retard the timing of the cam a-tad. (looser chain on the "pull-side" - however not loose because of the tensioner).

Thicker head gaskets are avail as well, for when a head is milled...

EDIT: Tough call on the "bent-valves"... All you do is fill the head chamber with a light solvent and look inside the ports for leakage. Let the solvent sit all day for your final determination of a leaky/bent valve. Also, may even be obvious signs of physical damage on a valve (piston hittting valve)...

I adjust my valves .008-.010 to give space for carbon-build-up - and then hot-rodding.... till I know for sure that the valves are clean.....

Robert

I'm sure my head is within factory spec on how much can be milled off, so no thicker HG needed.

Your test requires pulling the head, if I pull the head there is no way I wouldn't just tear it down and have the machine shop go through it. It would be silly not to given the history. Also, it is way more likely to see witness marks on the top of the piston than on the valve.

What do you think adjusting your valves to .008-.010 gains you? Where do you think you have carbon build-up that needs space, and how is that going to give you space for anything? And how would you know the valves are later "clean"? I don't understand your logic there, all that does is give you more slop between the rocker and valve (or cam), more valve train noise, and valve won't open as far. Is the thought to compensate for higher temps encountered when beating on the motor? Give a little extra room to protect from valve float? Get you a longer period before you have to readjust them (the biggest wear item on the valve train is the seat, as it wears the valves work their way into the head and rocker clearance gets smaller).

[epmedia]

I'm sure my head is within factory spec on how much can be milled off, so no thicker HG needed.

Your test requires pulling the head, if I pull the head there is no way I wouldn't just tear it down and have the machine shop go through it. It would be silly not to given the history. Also, it is way more likely to see witness marks on the top of the piston than on the valve.

What do you think adjusting your valves to .008-.010 gains you? Where do you think you have carbon build-up that needs space, and how is that going to give you space for anything? And how would you know the valves are later "clean"? I don't understand your logic there, all that does is give you more slop between the rocker and valve (or cam), more valve train noise, and valve won't open as far. Is the thought to compensate for higher temps encountered when beating on the motor? Give a little extra room to protect from valve float? Get you a longer period before you have to readjust them (the biggest wear item on the valve train is the seat, as it wears the valves work their way into the head and rocker clearance gets smaller).

Nobody understands my logic, so don't feel left-out .

Some engines get hot-rodded about once a month, some every day.

My logic for .008-.010" is for the "once a month" hot-rodding.

The extra .002" gives room for blowing out carbon build-up and/or valve & seat wear. It's best have a tad-more tap noise, than to have leaky valves.

Every time I have a need to adjust the valves, is when the clearances are too small, and there is leak-by.

My head and valves are very old. never been re-done since I've owned it. The first time I pulled the head, I must have cleaned several .001"'s of carbon from the valves and seats. The later times I pulled the head, did not have to clean the valves / seats.

I expect by 300K miles, I may not be able to hot-rod it anymore (valves and seats).

Every engine is different .

Robert

[jrcook320]

As of yesterday I started toying with the idea of doing a getrag 265 swap. I can get the flywheel, clutch, bell housing, trans, shift linkage and driveshaft out of an e12 528i from e21Adam for a decent price. If it shifts smooth I could pretty much just bolt it in, have the driveshaft shortened and go with a completely stock 240mm m5 clutch.

I'd also have to shorten my shift linkange/and modify the e12 shift plate, move an exhaust hanger and possibly modify my exhaust, or worst case fab a new down pipe and exhaust from turbo back to the center muffler. The 265 tailshaft flange is larger so I'd either have to swap output flanges or swap driveshafts.

The 265 has a separate bell housing which is good. It looks like it uses the same speedo drive, same style trans mount and shift linkage, same throwout arm, bearing, and slave cylinder.

The gear ratios will be slightly higher, especially in 2nd & 3rd, it looks like I'd gain some of my violent 2nd gear punch back and still have better r's and mileage with the 3.45 on the highway.

getrag 240 (what I have)
3.717
2.019
1.316
1
0.805

getrag 265
3.822
2.2
1.398
1
0.813


Well, after all that thought I pulled the trans last night and it was a little eye opening. I'm not sure it's going to be worth the effort to swap in a g265. My turbo downpipe currently runs so close to the bell housing that I had to clearance grind the housing for it to fit. If the bell housing gets any bigger I'll probably be signing myself up for fabricating a new down pipe & exhaust up to the center muffler. I'd also prefer to run the e12 driveshaft so i don't have to swap tailshafts on the trans.

After looking at my flywheel, clutch disc, and trans I'm just not sure it's worth all the extra work to swap in a g265. My metric mechanic tranny is so nice, and the clutch disc looks almost like new and the flywheel is in better shape than I would have ever imagined. The flywheel isn't grooved bad at all, though it does need machined. I could easily just slap another pressure plate on and run it just the way it is.

That said, I think that maybe I'm letting my desire to do something different and cool get in the way of practicality here, and maybe it's not worth letting best get in the way of better. I think a standard 228mm flywheel and heavy duty clutch will hold the power just fine and last me for years. After inspecing the parts, had in not been for this incident I bet my 215mm 4 puc would have lasted me another 4 years or so. If I just get a flywheel and clutch on the way I can then focus on rebuilding my diff, and the time to do that is now so I have an LSD on the tour (an open diff sucks).

here are pics from last night, a pile of parts:



rivet head sitting on friction surface:


Bent spring plate:


Missing rivet heads:


And here's the kicker, I can't believe how perfect the clutch disc and flywheel still look. I COULD just swap in a new pressure plate and run my flywheel and disc, it's like new and not what I expected at all. I'm not going to, I've already decided to upgrade and get something that will be more streetable, but this flywheel and clutch disc will be for sale:





I just talked to the guys at clutchnet.com. The guy was pretty helpful. He recommended that I go with their red pressure plate and copper metallic 6 puc disc and said that it will hold up to 375-400 ft-lbs, but that he officially has to rate it at 350 ft-lbs. He said that they upgrade the entire assembly with larger rivets, added heat treated strapping bands and with the hydraulic clutch it won't be that much stiffer than stock. I told him that TEP recommended that I go with their upgraded sachs sport pressure plate with the clutchnet 6 puc disc, but that I wanted to stay away from a metallic disc if possible. He said that they could do a 6 puc fiber carbon disc instead of the copper. It will be slightly less agressive (wont' bite as hard or wear the flywheel as much) in nature but that it will still hold as much torque as the metallic disc.

Right now my plan is 228mm sachs sport pressure plate, upgraded with added stapping bands by TEP and clutchnet's 6 puc fiber disc. It should be a good combo and much more streetable than what I have now.

[E21Adam]

Those pics and measurements are coming tomorrow. I ended up having to pick up the kids today.

[jjgbmw323]

Cool. What about a Spec Stage 3 clutch? They should have one for your application.

I am going to be upgrading my clutch on my new engine to match the 11 pound flywheel that I have and heard good things about Spec. I am going with a stage 2 plus which should be more than enough for my 2.9 m20 stroker conversion.

Here is the info:

http://www.specclutch.com/

Types of Driving:
Street, Drag, Pulling, Autocross

Features a carbon semi-metallic 6 puck sprung hub disc that has been the leading puck clutch in drivability, life and torque capacity. This unit is designed for street and race cars that require an aggressive but streetable engagement and high torque capacity. The hub is double sprung with spring cover relieves for flexibility and heat treated components for strength and durability. Also available in 3 puck configuration. Great for street, drag, road racing, pulling, rallye and drift.

* High clamp pressure plate
* Carbon-Graphite Friction Material
* High torque sprung hub and disc assembly
* Bearing and tool kit

[TKO383]

here are pics from last night, a pile of parts:

What is all this junk? This post belongs in the used tractor parts for sale forum....

+1 on the 228mm setup. simple, easy, and car will be ready for the 'tour.

[jrcook320]

What is all this junk? This post belongs in the used tractor parts for sale forum....

+1 on the 228mm setup. simple, easy, and car will be ready for the 'tour.

Here's the game plan... right now I'm trying to decide, is the aluminum flywheel worth the extra $135?

228mm 13 lb m20 flywheel (from CJ):
$125 + shipping
$50 to have it lightened
$40 for rebalance
$50 for a new ring gear
=$275

228mm 8.5 lb Aluminum Flywheel - Miller's Mule:
$360 + $50 ring gear = $410

Clutch:
TEP modified Sachs sport pressure plate, modified with added strapping bands
6 puc fiber/graphite disc from clutchnet.com (less agressive than a full metallic disc)
= $425

so the clutch will cost me between $700 and $835.

[Layne]

The forum cred you get from posting a picture of an aluminum flywheel is worth at least $135!

[jrcook320]

shoot, I can do that now for free:

[djminkin]

Were you valves bent? Ive seen this in the shop on an E36, and it usually gnarls the valves or a piston destroys the cylinder.

[jjgbmw323]

shoot, I can do that now for free:

Wow...Look at that.

[TKO383]

Were you valves bent? Ive seen this in the shop on an E36, and it usually gnarls the valves or a piston destroys the cylinder.

The engine passed all of it's compression tests. It does not appear to have any bent valves at this time.

[jrcook320]

Wow...Look at that.

Indeed. $410 from Jason at millersmule.

The engine passed all of it's compression tests. It does not appear to have any bent valves at this time.

we'll see...

[jjgbmw323]

It sure is interesting how they lightened it. Do you really need 8 pounds?
Not sure but that thing looks so cool.

My machinist got my 325i down to 11 pounds, and last I checked even the stock 323i flywheel was considered "light."

Here is mine....

[epmedia]

Use new hardware for your flywheel (with locking material), and "red loctite" and new hardware for your pressure plate.

AND dont spray anything onto your rear-crank-seal while buttoning-it-up...

Robert

[pastaroni34]

Its not about weight so much as the MOI (moment of inertia). A lightened flywheel is roughly 2/3 the MOI of a stock one. The aluminum one is nearly 1/3. Our ultralights are 1/5. If you include the difference a tilton clutch makes, you're total is about 1/10 of the original MOI.

Its also about safety. When a cast flywheel lets loose it explodes like a hand grenade. If a aluminum or steel one made from (for lack of a better word) billet breaks, it stays together.

Also, the aluminum one does not come with the extra holes.. but those can be added if necessary.

[epmedia]

Inertia is pretty cool for breaking traction on a light car, or pulling a load in "granny-low". I too thought "sceptical" about the idea of a light-weight" flywheel, however on a fairly light car, the light flywheel seems pretty cool.

Robert

[jrcook320]

Use new hardware for your flywheel (with locking material), and "red loctite" and new hardware for your pressure plate.

AND dont spray anything onto your rear-crank-seal while buttoning-it-up...

Robert

I've been thinking my rear main seal is leaking after only 35,000 miles, but I found oil seeping out of the flywheel bolts and the seal looks clean and dry. I realized I didn't put thread sealer and don't remember if I used locktite on the FW bolts. The rear main seal is viton (I happen to be a manufacturing engineer at an oil seal plant...) which is fuel and solvent resistent, it should withstand a light squirt of brake cleaner on the aux lip if it happens on accident.

I'll need to buy longer flywheel bolts for the 228mm flywheel anyway so there will be all new hardware. That brings up the question, do I use locktight on the bolts or thread sealer? The flywheel bolt holes run right through the crank into the crank case, if they don't seal oil will leak past. I will be spraying the oil out of the holes in the crank to ensure good seal, neither will work on oily threads.

Its not about weight so much as the MOI (moment of inertia). A lightened flywheel is roughly 2/3 the MOI of a stock one. The aluminum one is nearly 1/3. Our ultralights are 1/5. If you include the difference a tilton clutch makes, you're total is about 1/10 of the original MOI.

Its also about safety. When a cast flywheel lets loose it explodes like a hand grenade. If a aluminum or steel one made from (for lack of a better word) billet breaks, it stays together.

Also, the aluminum one does not come with the extra holes.. but those can be added if necessary.

Jason, what do think, will I be happy with an aluminum flywheel on the street? How much HP will the lower MOI be worth? If I can spend an extra $135 and make the car noticably faster then it would be worth it. If daily driver status suffers too much then I may shy away from it, I'm doing all this (going away from the small 215mm 4 puc, ect) to make the car MORE streetable, not less. I don't really want to lose much low end torque either...

The lower MOI is one reason to stay with the 228mm flywheel instead of going up to the larger clutch assembly.