e32 735i Getrag 260/6 5-Speed Transmission Swap
e32 735i Getrag 260/6 5-Speed Transmission SwapEstimated out-of-pocket expense for the entire job was ~$2500. One can reasonably expect to recoupe ~$1000 from selling a good used ZF 4hp22ep automatic transmission, a 3.91 or 4.27 limited-slip differential, and some of the auto trans electronic components no longer necessary. Figure a net cost of ~$1500, which puts it at a very acceptable range and is less than the inevitalbe auto trans rebuild that each of us will have to face one day.
This job is largely nuts & bolts and is not at all that difficult. Approach it as if it's nothing more than an extreme manual clutch replacement job to put it in the proper perspective. The key to succeeding is thorough preparation for lining up all the necessary components ahead of time. Most of the required parts can come from either an 88 or 89 e32 735i or an 89 or newer e34 535i. A quick check of the ETK shows identical part numbers for both cars for almost every 5-spd component.
The major components are:
- transmission, Getrag 260/6 (Getrag 260/5, 260, 262, and 265 will also work. Shift linkage mods are required for the 265. I recommend getting the 260/6 since it is a direct nuts & bolts fit)
- transmission throw-out fork
- cross member & rubber tranny mounts (the existing chassis holes for the cross member were widened for after 09/89 build dates. If using an 88 cross member, it will be necessary to slot the holes approx. 1/8" to get the holes to line up.
- flywheel, pressure plate, clutch disk, & throw-out bearing (use an e28 535i non dual-mass flywheel and clutch)
- pedal cluster assembly
- driveshaft (different length & the front yoke is different, the rear diff flange is also different depending on what diff is used)
- flex coupler, aka "quibo" (depends on transmission yoke style)
- clutch master & slave cylinders & hydraulic tubing & reservoir (reservoir optional, newer brake reservoirs have one or more spare nipples)
- shift lever/shift linkage assembly
Other lesser but non-trivial items are:
- pilot bearing (very important! will result in transmission damage if overlooked)
- manual transmission bell housing bolts (most of the bolts for the manual need to be longer than the ones for the automatic)
- differential (the automatic diff ratio may be too high for a manual trans)
- interior console panel (shift boot opening is a different shape & location)
- leather shift boot (check Ebay, dealer wants $57 for one)
- tunnel rubber boot seal & surrounding insulation
- catalytic converter support bracket -- I'll figure out a way to mount & reuse the one from my automatic
- clutch lever cruise control cancel switch. Note: it is shown in the clutch section of the ETK but will come up as "not applicable to this model". The dealer found it in the cruise control section of the ETK and it is the correct one
Let me dispell some unfounded rumors:
Some shops will tell you that you must change the DME, instrument cluster, & coding plug in order to resolve the electronic issues. I'm here to tell you that none of that is necessary and & recommend you avoid the additional expense, and I am speaking from experience, having successfully converted my own car, which is still running flawlessly almost 2 years later. The automatic DME will work fine with 1 simple mod. The factory automatic DME (-150 or -179) will result in a wandering idle speed. To fix this, all you need to do is put in just about any brand aftermarket performance chip, which you'll likely want to do anyway. This will completely fix the idle issue and will make the automatic DME 100% compatible for running with a manual trans. The only other issue is removal of the automatic trans will result with the "Trans Program Error" display in the dash. This can easily be corrected by simply jumping a wire to ground in either the CCM or TCU connector as discussed later. Alternately, you can take the car to the dealer and they can overwrite the eprom in the DME to permanently erase the trans program error message. Either way, the car will not go into "limp" mode, even if driven with the trans program message showing.
Parts:
I bought the bulk of the parts at a salvage yard, "Tom's Foreign" in Connecticut, a very honest outfit & quite knowledgable of the necessary parts & were able to gather them easily. They even provided me with mileage & VIN number for the donor car. The bulk of the components came from an 88 735i that was being parted. I had them substitute an e28 non dual-mass flywheel instead of the one from the e32, to eliminate dual-mass problems later on. As it turns out, the interior of the bell housing of my donor trans has ding marks which I gather is a sign of a past failure of one of the former dual mass components. edit: in retrospect, I kinda wish I had used an e12 or better yet, an e9 m30 flywheel. They are lighter than the e28 flywheel and still use the same/similar 240mm clutch disk & pressure plate.
I bought new parts for essential items for most of the normal wear items such as:
- pressure plate & disk
- throw-out bearing
- master & slave cylinders
- shift linkage bushings
NOTE: Please DO NOT e-mail me to provide an itemized list of explicite parts and BMW part numbers. They vary depending on what year & model the donor parts come from and for what year they're being adapted to & I haven't been particularly careful organizing my receipts to put a list together with that extent of detail. If you're going to succeed at doing a swap on your own, these are details best left up to you for getting thoroughly familiar with the components and tasks at hand.
If you want to sub it out & have a turnkey swap performed, shops such as Korman, Koala, & Lonestar can do them but command high prices for doing conversions. If you have a trusted local independent mechanic, he might be willing to take it on. If you're on the East coast, The Euro-Depot salvage yard in Concord, New Hampshire specializes in swaps as a sideline (ask for Joel), very friendly & familiar with all the details and can provide a DIY "kit" with most of the major components and puts them together all the time. What used parts he doesn't have on-hand, he can get easily thru 20 or more local connections in his network.
Issues:
The differential gear ratio is a significant concern depending on what year e32 is being converted. My 92 has a 4.27 lsd which is totally wrong for a 5-speed. An e34 535i manual will have a 3.46 which would work but could be a little too low for a heavier 7. Stock 88-92 e32 735i 5-speeds all had a 3.64 diff. I had the opportunity to buy the 3.64 from the donor car but chose to look for a 3.73 or 3.91 since I am already well accustomed to the 4.27's acceleration & highway rpm's. As it turns out, 3.73 lsd diff's are not that easy to find. They were used on 89 e34 525i manuals and 91-93 M5's and are not plentiful. The M5 diff gets into more compatiblity issues with hub sizes & may not be a suitable choice. I ended up using a 3.91 lsd from an 89 e34 535i automatic and it is a direct swap and is only a 7.4% change from the 3.64 that a stock e32 would have had.
The stock e32 ZF 4hp22eh trans and the Getrag 260/6 have the following gear ratios:
ZF 4hp22eh
1st 2.48
2nd1.48
3rd 1.0
4th 0.73
Rev 2.09
Getrag 260/6
1st 3.83
2nd 2.2
3rd 1.4
4th 1.0
5th 0.81
Rev 3.46
Driveshaft issues:
The stock e32 automatic driveshaft will not work at all. The Getrag 260/6 trans is about 6" shorter than the ZF 4hp22 auto. Depending on what year the manual trans came from, it will likely have a 3-bolt output yoke and a rubber flex-disk, aka "guibo"
(pic later)
On some models, the front may have a 4-bolt front u-joint arrangement similar to the auto. The rear differential flanges for automatics and manuals are different and will not mate with the auto input flange if a manual diff is swapped. This a problem regardless if the trans/diff comes from an e32 or e34. The auto has a 94mm hub diameter with 6x 8mm studs on an 80mm bolt circle and the manual has a ~105mm diameter hub with 6x 10mm studs on an 86mm bolt circle. One solution is to swap diff input hubs but the pinion gear gets its preload setting from the factory when the diff is made up and messing with the preload by swapping flanges can cause an early failure of the diff. Not to worry, most driveshaft rebuilding outfits are well experienced with mating the proper ends, at the expense of having to eat the core charge. I was able to get the driveshaft from the donor e32 but the front half was damaged beyond use and was so bad off they wouldn't even accept it as a core. The back half was ok but still had the wrong flange, studs & bolt pattern. That was corrected by simply replacing the rear CV joint with one from an automatic which slides onto the splined end of the driveshaft & is held in place with a circlip. I let the shop provide me with a new one along with a new center carrier bearing assembly since the donor one was also trashed. A complete freshly rebuilt drive shaft assembly was returned to me, ready to bolt in, and is smooth and has no imbalance issues.
Preparation of used parts:
It's a good idea to replace all of the externally accessible seals on a used trans. At a bare minimum, the shift shaft seal should be replaced since they are notoreous for leaking for the Getrag 5-speeds. It's a pain getting the old one out since it's so tiny. I ended up grinding a disposable screwdriver into a shape that would reach in and hook the inside brim of the old seal and it pried out easily without scratching the shaft seal surface.
(pic later)
Now is also a good time to replace the input and output shaft seals, although my used trans didn't show any signs of leaking so I left them alone. The used trans has 130k miles on it and rotates smoothly & shifts into all 5 gears plus reverse & the shift detents feel snug so decided to use it as-is without having it opened up. The old fluid drained clean and there were minimal metal filing deposits on the drainplug magnet. If it whines or pops out of gear or has syncro's that need replacing, I'll deal with it as required after getting it fully installed and back on the road.
Another thing to check is the plastic (yes, plastic) pivot ball on the clutch throwout arm in the bell housing.
(pic later)
The old one was badly worn and could cost a premature disassembly to replace if not starting with a new one. It fits into a thru-hole in the back of the bell housing and can be driven out from the back side with a blunt punch. I drilled a profile into the end of a wood dowel to crudely match the profile of the new one and tapped it in with a hammer. It took quite a bit of force to get it to seat all the way and the wood dowel kept from messing up the pivot surface.
If using a used flywheel, now is a good time to get the clutch surface re-machined and have the flywheel balanced. The machine shop asked me what the step height spec is for the clutch wear surface, there is a slight raised surface for the clutch disk wear surface. My e28 Bentleys shows a step and mentions that a step should exist but he states that BMW does not provide the info for the height of the step. The shop measured mine out where it was still virgin material and got 0.011" for the step height which agreed exactly with the value they later found on their computer.
(pic later)
After they machined the clutch surface, I had them bolt the new pressure plate I provided to the flywheel and balance them together as a unit. The new pressure plate had obvious signs that it was factory balanced, but the assembly was off by 8 grams. Typically an imbalance of more than 5 grams will manifest itself in a noticeable vibration. They stamped indexing marks into both the flywheel and pressure plate so it will go back together in the same orientation as it was balanced, & I installed the pressure plate with new bolts.
NOTE: The automatic ring gear/flex plate bolts are too short for the manual flywheel. Bentleys recommends using new flywheel bolts anyway so make sure to order the ones for a manual, for the same model that the flywheel came from.
Shifter R & R
This is a good time to rebuild the shift bushings to be able to start out with a good snug linkage assembly. Parts are relatively cheap at the dealer compared to getting a UUC, BavAuto, etc. short shift kit. As a minimum, get the items indicated in this jpeg
The ETK lists several part numbers for the knuckle which attaches directly to the shift shaft and the dealer provided the wrong part the 1st time. I printed the alternate page from the ETK and went back to the dealer with my old knuckle and was able to get an exact replacement. I was tempted to just press out the old plastic bushing insert and machine a new one out of Delrin and press it in but as it turns out, the link rod hole is oblong in the new ond and would be much more difficult for me to hit the proper shape & tolerances so spent the $18 for a new knuckle. It comes with a piece of sponge which gets coated with heavy grease front & back before installing it on the shaft.
A nice upgrade at this time is to install a short throw shift lever. The stock e32 shift lever provides smooth action but has a fairly long throw. Nearly all model BMW shifters will interchange with any other BMW. I ended up getting a Euro e36 M3 shifter since it provides a 30% reduction in throw and remains close to the stock height of the e32 shift knob, $40 at the dealer. As it turns out, the 30% reduction produces a noticeable amount of notchiness in the shift action & I would guess one with more on the order of 15% to 20% would provide a good match & I'll probably swap it out for the 1.9 Z3 shift lever. Here's a jpeg showing various model shifters:
Auto Trans Removal
First order of business: disconnect the battery (have radio code handy). Gee, Bentley even says to disconnect the battery when doing a waterpump, what's up with that?
Here's where the fun ends and the work begins -- removing the automatic transmission:
I did all of the work with the car up on jackstands at each of the 4 factory notched positions along the rocker panel, leaving the wheels on with 4x6 blocks of wood under the wheels as a safety precaution (I've been feeling tremors in the area over the past few weeks).
From underneath the car, disconnect the shift linkage cable on the side of the transmission and disconnect the 8-pin (pre-90 models have a 7-pin) Cannon connector on the trans. From inside the car, remove the console panel, disconnect the electrical connections on the auto shifter linkage assembly, and remove the 3 or 4 screws holding the base of the shifter to the top of the tunnel and pull the whole assembly out from above. The shift cable & wire bundle will pull up thru their feedthru grommets. I coiled the transmission wire harness around the vacant space on the sides of the console area so the car could one day be restored to an automatic if that were ever to happen.
I next removed the front & rear mufflers, catalytic converter, and the driveshaft. With the shift lever cable removed, you will find it is easy to take the trans out of park with the lever, for rotating the driveshaft to get to the next bolts, and then put it back into park to lock it, park is forward.
Remove the trans cooler lines: a 19mm flarenut end wrench will do the one on the side of the trans. A 19mm crow foot flare nut socket wrench works slick for removing the cooler line connection coming off the bottom of the trans just in front of the pan. Disconnect the radiator ends of the cooler lines. Remove the pan drain plug & take a long break while the ATF dribbles out of everything. Close to 5 or 6 quarts will come out of it.
Once it's drained, unscrew any clips near the steering box that the cooler lines are attached to and pull the cooler lines out one at a time from the front of the car. It may take some twisting or rotating but they should come out easily.
Disconnect the dipstick tube at the pan and remove the bolted bracket at the firewall and remove the tube.
The auto trans bell housing is bolted with a mix of Torx head bolts and conventional hex head bolts. I bought a 3/8" Torx socket set at Harbor Freight since that's the only size they had but if the bolts are too tight go to Snap-on or Napa & get 1/2" drive sockets. Temporarily support the pan of the trans with a block of wood and a floor jack and remove the rear cross member. I made this piece of bar stock to support the trans a long time ago when I replaced the auto rear output flange seal, and it bolts into the existing cross member holes on the chassis rails and makes it alot easier to maneuver under the car without having to have a jack in the way.
(pic later)
Lowering the trans will provide better access to some of the bell housing bolts. The ones near the top will take nearly 3 feet of socket extensions and a universal to get to them. Note that the starter does not need to come off, it bolts into threaded holes on the rear flange of the engine block and they do not go all the way thru to the transmission.
IMPORTANT!: Most of the automatic bell housing bolts will be too short for the manual bell housing. If you get into a bind like I did, Home Depot has a good assortment of 8.8 or 10.9 metric bolts. The old bolts on mine were grade 8.8 which I think has a comparable strength as an SAE Grade-5. Autozone, Checker, etc. only had a limited selection of metric bolts and they were too short. Napa may have them or if you have a well endowed hardware store, that could be another source.
Flywheel and Manual Trans Installation
Once the old trans is removed it is very important to install a pilot bearing on the end of the crankshaft.
(pic later)
The automatic does not use one but the input shaft of the new 5-spd will get trashed very quickly and there will be no end of vibration problems if the pilot bearing is not installed. The end of the stock crankshaft is already machined to receive the new pilot bearing. Some clutch kits come with an assortment of steel disks and a felt washer for the pilot bearing. These are obsolete parts and are only for use for the older open non-sealed style pilot bearing. Most replacement pilot bearings are sealed, and that's the only piece that needs to be installed. The rest of the steel & felt disks can be discarded when using the sealed pilot bearing.
Here's a little trick I stumbled upon to tuck away for the future if you ever need to replace an existing pilot bearing. Instead of paying big bucks for the special pilot bearing removal tool, pack a bunch of soft Wonder Bread into the hole with a wood dowel and a hammer. I would guess modelling clay or Playdough would work also. Keep packing more and more bread or clay into it and the old bearing will come out eventually,
Now is a good time to replace the engine rear main seal while the flywheel is off. Mine was dry as a bone & I've been running Amsoil 10W30 in it so if it were going to be trouble, It would certainly be showing some signs of weaping so I left it alone and will save it for the next clutch job.
Note: One of the flywheel and crankshaft holes is slightly larger in diameter than the rest and has a metal sleeve which sticks part way out of the end of the crank, or the sleeve might come out with the auto flex-disk, be sure not to loose it!. This mates with the larger hole in the flywheel. The auto flex-disk sleeve is the same as the manual one so I just left the old one in the end of the crank. The flywheel mates directly to the face of the end of the crankshaft, make sure both surfaces are clean. There is a large hardened flange that goes on the outer face of the flywheel. The auto flywheel bolts are shorter than the manual flywheel bolts so go ahead and get new ones. Bentleys says to use new ones every time. I don't know if they are "torque-to-yield" bolts or not.
Install the clutch disk and pressure plate with a pilot shaft to get the splines and pilot bushing axes aligned.
(pic later)
Some clutch kits will come with a pilot shaft, there are cheapie plasitc ones available for about $5. Make sure the clutch throwout arm and throwout bearing are in place and greased on the appropriate surfaces and grease the splines lightly. MAKE SURE TO PUT THE 2 SLEEVES ON THE 2 BOLTS ON THE BELL HOUSING ALSO!
(pic later)
Congratulations! You are now ready to mate the manual trans to the bellhousing! :-)
Try to keep the bellhousing faces parallel and at the same elevation so as to not bend the trans input shaft. I bought a nice transmission scissor jack at Harbor Freight for $49 on sale & it works great, not enough room for the ratcheting tie-down business though, so I used it bare, being careful that the trans didn't slide off. You can put the trans in gear & rock the output flange a little go get the splines to engage. If all is assembled properly, the trans should mate freely all the way to the bellhousing. Most of the bolts from the automatic will be too short for the manual trans, replace as required. My auto trans had conventional hex head bolts for the upper mounting bolts. I had to machine a socket to get it thin enought to clear the fins on the manual trans. I believe an original equipment manual trans car will have Torx head bolts all around and the sockets will be small enough to fit in between the fins without modification.
Linkage:
Wth the trans in place and supported, the linkage assembly can be installed. It's easier to do if the shift lever is not installed yet. This is also a good time to run a pair of wires from the reverse switch on the side of the trans, thru the tunnel to the interior of the car. I routed them thru the abandoned boot from the auto shift cable and blanked off the opening left from the auto wire harness. I pulled the wire harness thru the tunnel into the interior of the car and coiled it up under the console.
The rear linkage arm support bushing is a bit of a pain to install. (I made a mistake and used the used one that came from the donor car and that produced a little more slop in the linkage assembly. I will go back and replace it with a new one eventually if all that's necessary is to lower the crossmember temporarily). Cut away a portion of the sound deadening material. There is an existing hole and 2 tabs that it slips into and supports the tail end of the shifter support mount and the stud on the bracket will go thru a hole in the existing sheet metal brow on the back of the tunnel and gets a nut & washer from behind.
(pic later)
The rubber housing on the bottom side of the auto shifter will come out when the shifter business is removed from the top. Install the manual rubber boot thru the tunnel opening with the largest lip on the bottom under the tunnel and the smaller lip facing up in the interior of the car, above the tunnel. The shift lever with the spherical ball and sleeve can now be installed. Line up the plastic tabs on the outer spherical bushing east-west and they will snap into the slots on the sides of the aluminum arm opening when the shift lever is pushed firmly downward, no need to twist it into place, that's for removal.
Next, the shift link rod gets installed.
(more later)
Driveshaft Installation
The flex disk "guibo" can now be installed. Note that it is molded with thick and thin sections. It gets installed such that the thicker section is put in compression when torque from the transmission is applied to it under power. There are small arrows molded into the rubber. The arrows face toward the fingers of the respective yoke flange that it mates to.
(pic later)
The quibo bolts are installed with the bolt head on the metal quibo sleeve and the nut on the yoke flange side. Tighten the nuts, not the bolts, so the metal sleeves do not twist in the rubber when tightening.
Pedal Cluster Swap
There's no other way around it, this part is a pain in the a$$ but I found a shortcut that made it much simpler. In theory, all that needs to change is to remove the pedal shaft bolt & transfer just the manual pedals over to the existing automatic bracket. I bought the entire used pedal cluster assembly from the 88 donor car, complete with the brake & clutch switch brackets, clutch master cylinder & firewall boot, & reservoir & hose. My 92 automatic brake pedal bracket is identical in every way except for one minor detail: it's missing the small stamped sheet metal perch for the clutch pedal return spring (maybe they did a design change & eliminated the return spring for 92?). One look at what it was going to take to swap the entire bracket assemblies and all I could say is "there's no way that's gonna happen!" After looking at it a little closer, I realized all I need to do was cut the the spring perch off the manual frame and weld it onto the automatic frame. I was apprehensive about welding inside the car, so instead, I made a small incision in the perch while still attached to the overall frame, and welded in an L-bracket which I cut out from 3/16" thick bar stock. I welded in another stiffener rib, matched drilled the two holes for the upper stud and fluid reservoir line, and then cut that small sub piece off of the manual bracket. I drilled another hole for mounting it in the car and that's all there is to it, no swapping of pedal brackets required at all and the only mod to the car was the drilling of a hole for a sheet metal screw thru the existing bracket and firewall. There's nothing in the way behind the firewall for at least 1" or more for worrying about drilling or screwing into something critical. The end result is the spring perch is now mounted in exactly the same place it should be, and is very rigid, perhaps moreso than it's original condition. Now the pedal swap can proceed as per the theory: merely remove the pivot bolt and bolt them into the existing automatic's bracket. Everything else is there, the 2 tapped holes for mounting the master cylinder & the fluid reservoir hole. Problem solved & didn't have to mess with the steering column or wire harnesses. The newer models are even more congested with the power telescoping column motor so all the more reason to not want to swap the entire bracket assembly.
Electrical Details:
One cannot yank an automatic out of an e32 & not expect the Check Control to go bezerk with all sorts of blaring warnings. Numerous independent sources on the web have confirmed that jumping pin #5 on the CCM to ground (which is the same grey/brown wire on pin #33 of the TCU connector) will extinguish the "Trans Program" error that will show up. In spite of that, the engine will still run normally without going into limp mode.
The starter relay will need to be replaced with a jumper wire from terminal #30 to terminal #87, the terminals are numbered on the underside of the existing relay. Note that the car will now start in any gear with or without the clutch pedal depressed. In order to provide an interlock, one could use the same 4-pin switch as the later style brake light switch, one pair of pins is normally closed, which will be used for the cruise control cancel, and the normally open pair can be wired to the fuse box starter relay socket in lieu of the jumper wire from pins 30 & 87 and that will ensure that it will only start when the clutch pedal is depressed. The 88 donor car pedal cluster came with 2 switches, but they were not functioning so I discarded them.
(pic later)
I will have to sort out which wires need to be strung to the reverse light switch on the side of the transmission. I also bought the clutch cruise control cancel switch. The connector for it will be either be loosely taped or hanging free from the wire harness in the vacinity of the pedal cluster and should be instantly recognized.
(pic later)
All that's needed is to plug it in, and that will keep the engine from rev'ing to self-destruct when depressing the clutch while the cruise control is engaged.
To the best of my knowledge, the automatic DME and instrument cluster/coding plug can remain without swapping for the manual components. I haven't noticed any driveability issues since the swap.
735iL's with fly-by-wire throttles may provide unique challenges but fortunately mine is a conventional direct cable-actuated throttle so won't have to face that hurdlle. Mark D'Sylva says the differences with the auto vs. manual DME boxes are subtle and trivial so will leave that alone unless I find it doesn't run properly with auto box. As it is, I'm already running a manual eprom performance chip in a -179 Motronic auto box and other than seat-of-the-pants increase in performance, I've had no issues with it.
Parts Sources:
Salvage yards:
- Tom's Foreign: http://www.toms4n.com
- Euro Depot: http://theeurodepot.com Ask for Joel, he's very knowledgable about conversions and can usually put together "kits" minus driveshaft and diff, with good used parts for $1300-$1400
- Eurasian, Temecula, Calif. httomp://www.eap4parts.c I bought most of the new parts such as clutch kit, clutch cylinders, guibo, etc. from them. (They will be moving moving soon to northern Idaho.)
- Driveline Services of Portland (Oregon) http://www.driveshafts.com/company.html I sent them the donor driveshaft and they did a good job with quick turnaround. They credited me with 50% of the core charge ($37.50) since the front half was previously damaged beyond use.
- Sandia BMW, Albuquerque, NM http://www.sandiabmw.com Some of the less expensive nuts & bolts items are best left to the dealer unless you want to spend the time pouring over the ETK and can catch Matt of Maximillians, http://www.bimmer.com at a good time on the phone, 1-800-950-2002, to help with the nitty gritty of part numbers. Some things I was missing were the guibo bolts and hydraulic tubing and hose. The rubber hydraulic hose was $58 at the dealer so that would be worthwhile getting mailorder. I noticed later that the rear inboard rubber brakeline hoses have female fittings on both ends and they would work just fine & I bet they're alot cheaper than the clutch hose. The ETK shows a large coiled loop of metal hydraulic line which I can only gather, was an early design attempt to make a clutch damper. If you visit some of the e39 540i forums, you will find more info on the restrictor orifice/delay/check valve BMW now puts on the slave cylinder, and how to drill them out to get better clutch action. E28's , e32's, & e34's do not have the newer style damper, so instead of getting the large coiled tube, I'm using 2 short ones with the rubber one in between to allow flex and minimize the vibration & noise transfer from the engine to the cabin. The metal lines are $13 ea. at the dealer and were back-ordered & would have to be shipped in from Germany so I bought some short steel VW brake lines to finish plumbing the clutch, from Foreign Aide, my favorite local aftermarket VW shop -- much cheaper & they have the same metric ISO male threaded fitting and the same "bubble flare" tube end, thus I'll end up with an undamped system which is my preference. Afterall, one of the objectives of doing a 5-speed conversion is to get firm precise shifts & clutch action right?
Acknowledgements:
Bobby, who has recently converted his e32 and was very helpful over the phone to point out some of the "gotcha's"
Dave Kan's e28 5-spd conversion link
Fatdaddy's e28 5-spd conversion webpage (link later)
Brad Couvionne's webpage (link later)
Numerous Roadfly & Bimmer.info members who took the time to answer my posts and send e-mails
And last but not least, many thanks to my loving wife for tolerating this project and a special thanks to my 12 year-old son for all his help digging the trench to run the gas line to the shop so we can have heat in the shop for tackling this untimely winter project.
gale, 92 735i