722.6 build - Page 3 - PeachParts Mercedes-Benz Forum

duxthe1 · #31 08-07-2015, 08:24 PM

I was able to get 6 frictions in K3 but had to use a 2.8 mm steel as the backing plate. The piston has what looks to be 1.5 - 2 mm that csn come off so I'm going to cut 1.2 mm off so that I can keep the 4 mm backing plate in the stack.

duxthe1 · #32 08-10-2015, 09:57 PM

Trimming the K3 piston allowed me to assemble the clutchpack with 6 frictions, stock 2.8 mm steels, and the 4 mm backing plate. With the thinnest snap ring I get 1.5 mm clearance. Neat fact, K3 is only disengaged in 3rd gear.

With K3 assembled I went on to install B2 and B3 into the case. B3 is only engaged in reverse so it was left alone. From there the case is installed and buttoned up. I was able to find a 3 bolt output flange that will match the coupe's driveshaft in the graveyard of glycol contaminated cores.

All that is left is to prep and install the valvebody. A simple mod is recommended to help K3 filling. Joking with coworkers that have been watching me build this thing I pulled out a sharpie and named it "Unbreakable" Let's hope my hubris doesn't come back and bite me in the ass.

97 SL320 · #33 08-11-2015, 07:49 PM

Something else think about, make sure there is enough engagement of the frictions. ( RE the splined hub that the ID of the friction plates engage. )

The old hubs will have some marks on them for you to judge if there is enough in the direction you have added plates.

whipplem104 · #34 08-11-2015, 07:51 PM

The only one that this is a real concern on is the b2 engagement to the k3 clutch carrier.
The rest are pretty forgiving.

duxthe1 · #35 08-12-2015, 01:30 AM

That's central to the decision to leave B2 alone. There is plenty of K3 real estate on the backing plate side of B2 but another friction and steel on the piston side would run right off the K3 basket. I don't give up easy but it was obvious that there is no win in B2 when the backing plate is off limits.

duxthe1 · #36 09-18-2015, 10:30 PM

Happiness is a blue box and lots of wires. I got my PCS trans controller in this week. I started installing it yesterday. I figure while I'm still scrounging hard parts to install the trans I can get the tcu reading rpm, map, tps, ect so all of that stuff will be ready to go once the trans is bolted in. So far I've got power, ground, rpm, and brake light switch connected. Not a very interesting datalog but a datalog nonetheless. Ive got a map sensor with harness waiting to get wired in this weekend. I think I may grab a remote tps from one of the Benz's in the u-pull yard and wire that in.

duxthe1 · #37 09-27-2015, 08:24 PM

A bit of an update, getting closer to the install. Map sensor installed without any hitches and now reading MAP with the TCU. I got my hands on an early ML shifter which uses the 202 housing. The down side is that there is no W/S switch in the ML shifter but the price was right (00.00$). There is an early S320 in our parts cars yard and it has the snow chain switch. I'm planning to use that as my W/S select, not that the coupe will see much if any snow with a turbo 4-M wagon waiting to tag in. The shifter wired in pretty easy and is recognizing all positions. It has a reverse / park lockout solenoid that prevents shifting into reverse or park above 6 MPH. I'm planning to use one of the additional PWM outputs in the TCU to replicate this function. Additionally I plan to use another PWM output to replicate the neutral safety switch funtion by powering a relay to allow starting only in P or N. Reverse lights thankfully are handled by the shifter without intervention by the TCU.

A trip to a U-pull yard this weekend yielded a torque converter from a C230 Kompressor. Unfortunately that car came to the yard without a shifter. I snatched up the dipstick tube from it. I dont know if it will bolt to the 104 cyl head but worst case scenario it will still bolt to the trans case and bellhousing. I have yet to pull a TPS sensor. The TCU can run the shifting tables off of MAP alone but I do plan to get a TPS installed. Aside from that all that is needed is a set of trans cooler lines for the 104 / 722.6 combo.

97 SL320 · #38 09-27-2015, 09:16 PM

Something to be aware of with the stock converter. As things wear, the converter clutch tends to drag. Early on you will get vibration at light throttle 4 or 5 th gear ( just like you are in too high a gear with a standard shift and slightly squeeze the throttle ) In severe cases, stalling when shifting into gear can occur.

The fix is to have springs ( Sonnax ) or rubber bumpers between the plates ( Alto ) installed in the converter clutch.

Also, do this test on any converter you get: Install the pump on the converter and rotate it feeling for binding. ( iron housing and 2 gears ) I just got a reman MB 18 converter from Trans Star / Recon that has concentrically issues between the two steps on the converter hub that won't let me rotate beyond 270 * with the original pump bushing ( I don't want to force it ) . The large diameter is where the bushing and seal ride and the slightly smaller diameter where the pump gear is located.

I'm going through Mom's 97 C280 722.6 trans as a 164 K preventive measure.( k2 bushing and trying to locate the intermittent ZZZzz noise that suddenly occurred recently. )

97 SL320 · #39 09-27-2015, 09:19 PM

I believe that the snow chain / ASR switch is momentary not latching so it may not work.

duxthe1 · #40 09-27-2015, 10:54 PM

Digital inputs for the TCU can be configured as momentary or toggle as well as active high or active low. There is also a digital output that can be configured as a snow mode indicator. The question is do I try to put the indicator in the dash or just use the illumination in the switch as the indicator.

duxthe1 · #41 10-31-2015, 01:09 PM

Been a while since I updated.... Had a disappointing trip to the junkyard this morning. They showed a 96 S320 in inventory so I headed out to find a 4/96 car. Still no cooler lines for the 104-722.6 combo. This was the last hope so new lines will be ordered from the dealer on Monday.

Since the last update I did manage to get a throttle position sensor setup. I pulled the sensor, bracket, and cable from an early 210ch car. I had to get creative but managed a nice installation. I lengthened the pin that the teflon roller rides on in the throttle linkages. The pin now also pulls the cable to the tps sensor. Since the cable pull has a larger diameter hole than the original pin I had to make the pin larger and also a new brass roller to match. I turned and slotted a ferrule to hold the end of the cable and used part of the 210 bracket to mount it off of the air horn. When actuating the throttle, the cable is pulled neatly between the two vacuum nipples on the intake manifold. The sensor itself is mounted on the fender using one of the diagnostic socket screws with a minimal amount of the 210 bracket.

Neat thing about the tps sensor is that it is a redundant sensor and later when adding EFI I'll have an easy solution for tps, though I will have to fab a different bracket with the air horn removed.

As it stands next weekend will be my target installation date.

duxthe1 · #42 11-07-2015, 09:33 AM

ITS ALIVE!!!! Spent last night installing the trans. Everything went pretty well. The output speed sensor gave me a little grief but a little tweaking of the bracket got it to play nice. I ended up ordering cooler lines from the dealer but they were shorter than I'd have liked. Had to use the longest cooler hoses to make them work. The driver's side ends up not having a 2nd mounting bracket. Not the end of the world.

The shifter dropped right in and fits the console wood perfect. The original trim ring doesn't snap down very well. I need to get the later part to have it sit flush like its supposed to. Had to cut a ~4" section out of the shifter linkage. A previous owner of the car had a later style shift knob that sat rather loose on the original shifter. (Weak sauce) I was pleased to find the tape wadded up inside cleaned out ok and it actually installed on the new shifter no problem.

The new electronic speedo went in without any trouble either. A single wire runs it and was easy to add to the OE connector that came with the speedo. It reads almost exactly 10K miles less than the original. My oil change schedule will be unaffected. It does read a bit fast with the TCU's as delivered calibration. I'll just have to drop the "pulses per mile" until it agrees with the TCU and GPS.

Five hours after starting I was pulling the car out of the shop. Having all of the sensors and wiring setup prior to install made it a relatively easy swap. Against Whipple104's suggestion I pulled the 13 pin connector apart and ran the individual wires through the body instead of cutting a hole large enough to pass the connector. I went through the body where the original kickdown solenoid's wire used to. For a single wire it had a good size opening and plenty of grommet to accommodate the new harness.

The first drive on the as delivered calibrations went ok. It did shift into all gears although pretty late. The tables are mostly TPS driven and the 104.980 needs a lot of throttle to get moving so first tuning step is to get it shifting sooner with more throttle. I did notice a consistent hard shift into 3rd and hard downshifts into 2 and 1. I'll work on seeing if I can dial that out with the pressure tables.

And that's where its at. I'm very happy with my results so far. Whipple104 delivers an awesome product. Its not plug and play but easy enough I was able to not miss a day on a daily driver.

whipplem104 · #43 11-07-2015, 10:56 AM

Glad you got it going. Sorry I did not see you call last night. I put my phone on silent when I get home most of the time because crazy people call at all hours. Just kidding.
Take a datalog of it running through the gears and email me with that and the current cal file retrieved from the tcu.

duxthe1 · #44 11-14-2015, 07:51 PM

So I've had the trans installed for a week. Probably put about 200 miles on it so far. Had a few teething issues getting my tuning laptop to work consistently with the TCU but everything is working great now. I've got a really good driving tune in it already. It would be hard to tell it is not an OE setup from the driver's seat. The tune that came on the controller wasn't too far off and with Whipple104's guidance I've got a well setup trans in short order. Very well behaved in normal commuting but when driving aggressively I have it hitting 2nd hard enough to break the tires loose.

There's is still some stuff that needs to be wired up. The neutral safety and reverse lights namely. I'm also keen to incorporate the reverse / park lockout in the shifter. Snow mode is on the list too but a low priority given the coupe never gets driven in the snow.

There's little doubt that I'll spend a fair bit of time and effort dialing in the last few % of the tune . For now, I've got a buddy with a nice 2wd 124 wagon. Gonna have to light a fire under him once he sees how nice it is having a 722.6 in the tunnel.

duxthe1 · #45 11-28-2015, 09:44 PM

I took the coupe on a 700mi round trip over the holidays. Denver to Montrose and then down to Orvis Hot Springs. I tanked up before leaving and rolled into Grand Junction with half a tank of fuel. After putzing around Montrose for a day I tanked up and averaged 25MPG. I'm now turning 2500 RPM at 75MPH. I'm really, really loving 5th gear.

I have been using MAP based shift tables and pressure tables. I was set up to shift early and let the WOT tables handle the need for more revs. This didn't work out too well trying to get up over the passes at 10K ft. The low atmospheric pressure coupled with low engine output skewed my tables enough to have to constantly have to row the shifter to get up and over.

I really liked this setup around town but it obviously wasn't going to cut it on road trips through the Rockies. I reverted my shift tables over to TPS for the return trip and kept the pressure tables MAP based. This worked out quite a bit better. The coupe needs 3rd gear and 4500-5000 RPM to make the passes at speed. I had a little 3-4 4-3 gear hunting but once I took the cruise control off and manually fed the throttle I was able to prevent it. A bit of table tuning can improve it but I'm not motivated to drive 2 hrs one way to test the changes.