2 years later...another guibo ready for replacement

[jgerry2002]

Another note on U brackets.

The high stress load/unload will also stress the exhaust if you track your car and use the factory vibration bracket off the transmission. I actually cracked the last factory center resonator that was in the car. But you need to be in high load, full throttle, full brake situations lap after lap, which is not something you ever get on a street car even on a "spirited" back road.

I'm now convinced the factory had 100% the right approach here.

I'm going to change my U bracket for the tab system (or possibly just modify my u bracket to include body tabs) in my tii by the spring.

I will say that I think U brackets are ok for a lightly driven street car. Probably few issues (if any) over time if you shim them right.

[c.d.iesel]

...thanks Tom for adding - you took the words

and Dia. right out of my mouth.

valid points about the stack of washers at the guibo

[Guest Anonymous]

Under acceleration your motor mounts might allow the engine to shift and be your root cause. While you have it up you might check your motor mounts. I actually installed my driver side upside down which made the engine mount way soft.

Have fun

[tjones02]

The 2002haus bracket is great, all it needs is the trans to be shimmed up about 8-12mm depending on the car.

Like a full centimeter's worth of washers? That seems a bit excessive, or I'm misunderstanding something....

There is room on the threads of the E21 trans mount, I don't see a problem.

If you want an inexpensive true bolt in 5speed conversion bracket (no welding, no drilling) then the 2002haus one is what there is. That or you can spend the $$$ on the Metric Mechanic one.

If you don't mind drilling holes, welding etc. to do your 5spd conversion, I have no problem with that original way of doing it. We just get cars at our shop that are so original or restored that we have a hard time justifying welding and drilling into time capsules, $40K Tii's or $80K 2002Turbos.

So, like I said... the ORIGINAL design for that bracket had a Z bend in it... I didn't design it the 2002Haus one, but I can work around it.

On a similar note, I have seen the factory 4spd mounting ears out of alignment by as much as that. There are and were otherwise stock '02s that ate guibos at an alarming rate... I have re aligned stock ears to fix that on more than one car. When you are building a bracket that bolts to those you simply have to adjust for the hand welded/installed original ears. You have to understand that I've done dozens of '02 5spd conversions and Sean Casey here has probably done more than 75.....

[KFunk]

There is room on the threads of the E21 trans mount, I don't see a problem.

Yeah, I'm just trying to make sure I'm understanding correct. That seems like a such a distance that it would be better covered with a large spacer instead of a stack of washers.

I haven't started measuring things yet, but I have a 5-speed, all corresponding parts, and a U-bracket sitting at home. Just arrived today, thanks Tom, Dave, Jake, etc.!!

I may go with the U-bracket for a while, but I will be heavily abusing the car at autocross and track days.... so I may switch it out soon. The U-bracket just doesn't seem mechanically intuitive to me. It sits way back behind an unsupported piece of metal. I had it sent since it was cheap and required very little mods to work (doing way too many other things to car right now and don't want to pile on more), and I'd heard no complaints until I saw this thread yesterday. Now I have doubts. Perhaps if it was reinforced with some angle iron, then it might hold up better.

My car isn't pristine at all, but I do like to avoid drilling new holes that could rust out, and I was trying to be lazy....

[M3M3]

Jim and I installed our sequentially serial numbered 02haus brackets at about the same time. both of us did both installs. i tracked my car with mine. i had no issues at all with the bracket.

only thing i had issues with was the workers at the bmw factory that built my car. they must not have read CD's post about the crucial 80mm measurement. my factory tabs were almost 10mm TOO LOW. i had to shim up the bracket to compensate for factory worker bad day.

[Colin]

Jim and I installed our sequentially serial numbered 02haus brackets at about the same time. both of us did both installs. i tracked my car with mine. i had no issues at all with the bracket.

only thing i had issues with was the workers at the bmw factory that built my car. they must not have read CD's post about the crucial 80mm measurement. my factory tabs were almost 10mm TOO LOW. i had to shim up the bracket to compensate for factory worker bad day.

I don't know why people perpetuate the myth that these cars were built by master craftsmen. The build quality is indeed high for the era, especially when compared to most of BMWs competitors, but that doesn't negate the fact that there were definitely "that'll do" bits on the cars as they rolled out of the plant.

[jgerock]

Didn't mean to start a whirlwind of keyboard pressing on this one!

Just crawled out from under the car after work:

1) I cannot visibly see the bracket move down when I pull on it hard.

2) I can push up on it a tiny bit, but it starts compressing the E21 tranny mount. The shift tower support is firmly in place.

3) Since my exhaust is still in place, I cannot place a straight edge directly under the two factory tabs. If I place a metal broom handle against the frame rails at the rear-most point of the U bracket, I measure just under 2.5" (63.5mm) from the frame rails to the top of the bracket (where the E21 mount sits). Will remove the exhaust and take another measurement with and without the bracket in place.

The bolts/nuts securing my guibo to the driveshaft and trans are new BMW ones (17mm wrench bolt side and 16mm wrench on the special locking nuts).

Washers were only installed on (1) side of the guibo (facing the driveshaft) to take up the space (est. 1/8").

Driveshaft is brand new unit from DLS in Portland.

I believe the 2002 Haus bracket works properly and it is a great idea. I just think there are other issues with my car that are leading me to try different mounting procedures.

For instance, the OD tranny I purchased from eBay arrived with a bent shift selector rod (downward). I was able to bend it back straight using a similarly sized thick-wall pipe I cut from the rack at work. It appears to be a tight fit between the large 6-hole guibo, but similar to others I have examined.

These pictures were taken using the El-Cheapo guibo

After first test drive

El-Cheapo on left, febi/Bilstein on right

Installing the better quality guibo (flex disk) remarkably improved the drivetrain but there is still interference on hard acceleration. Those of you who have been on drives with me know I do NOT baby my car and have heard me say too many times that I need an LSD diff.

a) Is the shift selector shaft still bent down too far? I will take more measurements in the next few days.

Is the current bracket 80mm from the framerails? Will remove the exhaust in the next few days to measure.

c) Is the guibo under stress? I will loosen the nuts and spin the driveshaft.

d) Am I an anal Engineer? Hell yes.

e) Do I trust Rob Torres? Hell yes. He and Keith Kreeger are the main reasons why I purchased a tii.

[BillWilliams]

Motor mount(s) condition?

[jgerock]

Motor mount(s) condition?

Will examine them PM Friday.

A PO installed new ones back around 2002 when the car was completely rebuilt. Engine moves around a little, but I have not seen evidence of mushy/cracked mounts.

[tjones02]

Motor mount(s) condition?

Will examine them PM Friday.

A PO installed new ones back around 2002 when the car was completely rebuilt. Engine moves around a little, but I have not seen evidence of mushy/cracked mounts.

While you're there check the drivers side block bracket to be sure it isn't bent. The flanges should be parallel, right angles not crooked Z shaped... if that's a good description.

I have always shimmed Torres brackets to get the level to 80mm, and then adjusted from there to get the guibo spinning smooth. Generally 78-84mm depending on the car...

OK, I have to say that 40K miles of not easy driving can easily crack a guibo like that..... on the same page I have seen '02s with the same 5spd's and "624" guibo last 100K plus without issue. Same goes for the old '02 style guibo....

[TTyMiller]

Congrats on the plates; it makes life so much easier!

[jgerock]

Todays update..

Removed exhaust including the manifold down pipe.

Loosened the (3) 16mm wrench size guibo bolts and rotated the drive shaft. The lower (2) were slightly tighter than the top one. All three nuts had the same (2) thin washers between the guibo and driveshaft yoke.

Hard to tell where the rubbing takes place but there is only 1.6mm clearance between the guibo O.D. (at one of the bolt locations) and the shift selector shaft.

Bill Riblett came by today and gave it his experienced eyeball. He pointed out the guibo may be rubbing against the right side shift tower mount that bolts to the tranny housing. I measured a much larger gap there than at the shift selector shaft. Bill then tried to rock the engine while I examined the engine mounts from below. Both appear fine.

Based on these pictures, I'm guessing the guibo is flexing and hitting the transmission housing just under the shift selector shaft, the selector shaft and maybe the right shift tower mount.

The current guibo is toast. Cracked on both sides and I can deform it without too much hand pressure.

This is 1.6mm (three feeler gauges)

[jimk]

Because there are rubs on the transmission, are there rubs on the guibo on al locations or only on the the driveshaft bolting locations? If so, the trans rear is probably dropping at times and the d.s. flange moves toward the tran (relatively speaking) when there is an up angle in the vertical plane between the d.s. centerline (cl) and the trans shaft cl.

I do not subscribe to the horeshoe rear support because downward bending moment it places on the support brackets (chairs in structural lingo). Take a horeshoe, grip it by the tangs and place a 10lb weight on the bend. You would have to be a real he-man to hold it horizontal like the horeshoe mount has to hold the weight of the trans, not to mention the inertial vertical loads on the road. Structural guys, comments? Jim, break out your statics books (sophomore level stuff).

[jgerock]

Jim -

I have examined the guibo very closely and it is difficult to determine exactly where the rubbing takes place. There appears to be some worn high spots at the (3) inner bolt locations near the transmission output shaft. The end points of the directional arrows are slightly worn away. I understand the cantilever effect (bending moment) on mounting things this way (I kept some of my Engineering books including Statics and Strengths of Materials), but the bracket doesn't move downward at all when I pull down on it. The car isn't high enough to put full body weight on it. One issue that I may have is that the (2) 13mm wrench size bolts that secure the bracket to the original body tabs don't have a large washer under them to spread the load. The two holes in the bracket are slotted for side-to-side adjustments.

Is the E21 trans mount compressing just enough to allow guibo interference? Not sure, but just a thought.