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Thread: Euro 6 speed swap and Diff build

  1. #1
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    Euro 6 speed swap and Diff build

    Disclaimer: The best and most comprehensive DIY write up for dropping the transmission and changing the clutch is from Vinci. The process for the swap is the same, some of the parts are different.

    http://webspace.ringling.edu/%7Edplassma/cj/cj.html


    Day 1.

    Actually not really day 1 because I have spent hours researching what I need, finding parts, and waiting for delivery of stuff. I think I have everything here. I am doing a couple of extra things while I have everything torn apart. Motor mounts, exhaust gaskets, and rear main seal are the main things for me but things others will want to consider are O2 sensors, guibo, transmission mounts (mine all new this spring) and this would also be a great time to do headers if one so wished.



    I actually had to drop the car off today and let my buddy do some work as I had to go to work myself today and the driveshaft people wanted the shaft today and the machine shop wanted the differential. When I showed up, exhaust, driveshaft and transmission was out. I helped get the diff out. If anyone is contemplating a diff rebuild, BUY mcoupemindy's stud kit. I haven't put it back in but can only imagine how horrible it would be without them.








    Transmission out!



    If anyone remembers my "grinding in 2nd gear" thread. Here is the cause.





    For those who don't know what that part is or what it is supposed to look like, it is the shifter carrier and it is supposed to be straight in both planes.

    I had to modify the new shifter carrier, shorten 3.5 inches and modify the cup with some grinding to accomodate the UUC short shift kit.

    Before modification





    After





    And the shift selector rod needs to be shortened 3.5 inches also. It is a hollow tube. I cut it, slightly enlarged the holes and placed a solid 5/8 inch piece of steel between inside spanning the new weld. I ground down the welds and for today, primed and painted the rod. If I had time, I would have powdercoated it but I need the piece tomorrow, my car doesn't see snow and this is in a very well protected area of the car so the paint is going to hold up very well. Also, if I get enough people on the group buy, it will be replaced shortly with a DSSR from UUC and I can just throw this part out. This is only the first coat, it actually looks much better now after 3. Also, hurricane Issac is reaking havoc with my drying time.



    Tomorrow afternoon I should be rebuilding the diff and installing the new clutch and transmission. Hopefully lots of pics tomorrow and a drive review.
    Last edited by Wertles; 09-14-2012 at 11:55 AM.
    1999 M Coupe Boston Green, Beige, H&R/Bilsteins, Underdrive Pulleys, Euro 6 speed, UUC SSK and Randy Forbes in the back
    2002 2.5 Z3 roadster Oxford Green, auto, all stock
    2013 Ram 3500 Crew Cab Dually 385 HP, 850 ft lbs torque at 1600 rpm, all stock and staying that way
    2004 Mini Cooper Chili Red, daily driver, modified almost daily

  2. #2
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    Perfect - this is the kind of writeup we need for everyone interested!
    Last edited by kojohns; 09-04-2012 at 05:13 PM.

  3. #3
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    So, is there a kit for replacing the shifter pieces and you are fabricating to save money or time, or is fabrication necessary?

    Let's see pics of the transmission and the clutch (unless I missed these somewhere).

  4. #4
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    Quote Originally Posted by Mr Bingley View Post
    So, is there a kit for replacing the shifter pieces and you are fabricating to save money or time, or is fabrication necessary?

    Let's see pics of the transmission and the clutch (unless I missed these somewhere).
    There is not yet a complete kit. The two pieces that are unique only to this swap (meaning 1 off pieces) is the aluminum shifter carrier ( the aluminum piece) and the selector rod. I already had the carrier here because I knew I had to replace the bent one. Rob at UUC was nice enough to give me the dimensions to cut, 3.5 inches or 89mm to be exact, and how to modify the cup so as to fit the short shift kit. When I order the kits, I am going to have UUC do the modifications to the carrier there as they will match the price of what it cost me to have it done (I didn't trust myself welding aluminum) and I won't have to run around town wasting gas. The selector rod is a bit more difficult. They would need to make them from scratch or have enough to do a run. It was going to be over $250 if i wanted them to make it for me. For a $10 piece of solid steel rod and a $17 drill bit, i was able to modify my own and it looks stock, not that anyone cares about that. Meaning, it doesn't look like a thrown together job. I talked with Rob today, and if I can get 10 orders, he will do a complete kit with DSSR for a great price. Anything less will basically be the same price but without the DSSR as I lose the bulk pricing and the price of the DSSR just gets too expensive to meet the $2500 goal. At that point, I will continue to modify my own. We shall see.

    Just got a little bit of bad news, of course, the driveshaft is just a little bit bent. They are going to cut it anyway then recheck it. If it is still bent (most likely it will be) they will make a new one. Do it once, do it right. It will just take another day or two.
    Last edited by Wertles; 09-04-2012 at 08:56 PM.
    1999 M Coupe Boston Green, Beige, H&R/Bilsteins, Underdrive Pulleys, Euro 6 speed, UUC SSK and Randy Forbes in the back
    2002 2.5 Z3 roadster Oxford Green, auto, all stock
    2013 Ram 3500 Crew Cab Dually 385 HP, 850 ft lbs torque at 1600 rpm, all stock and staying that way
    2004 Mini Cooper Chili Red, daily driver, modified almost daily

  5. #5
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    Well, if they are going to make you a new drive shaft from scratch, be sure to have them put in HD U-joints with grease nipples. And, if they can do it, make the U-joints replaceable with end caps (probably not possible, but worth a try).

  6. #6
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    How does the carrier get bent like that?


    Mods: Remus 76mm exhaust, CDV delete, ASA AR1 18in staggered wheels, Turner 12 mm spacers, custom red tails, Kenwood deck/Sirius/BT/USB, ZHP knob, Redline boot, LeatherZ armrest, Amsoil all around, red needles, Akebono Euro brake pads, 34k original miles!

  7. #7
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    Quote Originally Posted by BlackjackM View Post
    How does the carrier get bent like that?
    It's not something your coupe will experience on a daily basis.

    1999 M Coupe Boston Green, Beige, H&R/Bilsteins, Underdrive Pulleys, Euro 6 speed, UUC SSK and Randy Forbes in the back
    2002 2.5 Z3 roadster Oxford Green, auto, all stock
    2013 Ram 3500 Crew Cab Dually 385 HP, 850 ft lbs torque at 1600 rpm, all stock and staying that way
    2004 Mini Cooper Chili Red, daily driver, modified almost daily

  8. #8
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    Quote Originally Posted by Wertles View Post
    It's not something your coupe will experience on a daily basis.

    That'l do it--nice little dinger there.

  9. #9
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    Quote Originally Posted by Wertles View Post
    It's not something your Roady will experience on a daily basis.

    Fixed it

    Makes sense now.


    Mods: Remus 76mm exhaust, CDV delete, ASA AR1 18in staggered wheels, Turner 12 mm spacers, custom red tails, Kenwood deck/Sirius/BT/USB, ZHP knob, Redline boot, LeatherZ armrest, Amsoil all around, red needles, Akebono Euro brake pads, 34k original miles!

  10. #10
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    Day 2.

    Not much done today. We are still waiting to hear the verdict on the driveshaft. They put it on the balancer before they did anything to it and it almost shook their machine to death. Guess that would explain my constant rattling in the car. They are going to rebuild the whole thing, including the center bearing. I am not sure I even want to know what this is going to cost but do it once, do it right. Looking at another day or 2 before they get whatever they need.

    So, in the mean time, let's upgrade the diff to a 60% lock up. Got the diff torn apart and I don't have the normal diff. Apparently BMW put two different types of differentials in our cars, the one that is explained well on bimmerdiffs.com and one that is not, ie the Motorsports diff. That is the one I have. Maybe mcoupemindy will chime in and explain the technical difference between the two, but in the mean time, in my Diffs for dummies explanation, my diff already has 4 clutches, is great for racing and auto cross, but is not capable of increasing lockup percentage (easily) and doesn't perform as well in the rain or snow as impaired to the "standard" diff. Fortunately Jonathan, YOU DA MAN, foresaw this as a possibility a month ago and shipped me out two sets of clutches and dog ears, one for each. For those. I do not need the diff machined now so I have all the parts to rebuild...except a diff cover gasket and output shaft seals. For those refreshing their Diffs, please take it from me, spend the extra $9 and have these on hand. I could have had stuff back in the car today but now have to wait until Friday for those to come in. It is NOT a part your dealer will have in stock. So, a good cleaning, some masking tape and some spray paint, and voila! A nice pretty diff.





    I stripped the old trans of the mounts and guibo since I am reusing them (only 3000 miles old) and called it a day. As I was leaving, my buddy was on his way to bring back the transmission. Pics tomorrow. The plan tomorrow is to change motor mounts, paint the front cross member, change rear main seal, change out the clutch, install the transmission, linkages and short shift kit. We will see how that all goes because work tomorrow may go long.
    1999 M Coupe Boston Green, Beige, H&R/Bilsteins, Underdrive Pulleys, Euro 6 speed, UUC SSK and Randy Forbes in the back
    2002 2.5 Z3 roadster Oxford Green, auto, all stock
    2013 Ram 3500 Crew Cab Dually 385 HP, 850 ft lbs torque at 1600 rpm, all stock and staying that way
    2004 Mini Cooper Chili Red, daily driver, modified almost daily

  11. #11
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    You may notice that with the UUC shifter, the bottom of the selector rod is so long that it may contact the quibo when installed in the car.
    2002 Alpine White w/ Black 368 (<OO \(||][||)/ OO>)
    Power: Custom Exhaust w/ High Flow cats, CSL headers, built, low-compression Supercharged and aftercooled S-54, ViPEC standalone ECU, Vortech V2 Si trim
    Driveline: Euro 6 speed, 3.64 diff w/ 40% Lockup, Rogue Octane SSK, UUC Red TME kit, UUC Stage 3 LTW Flywheel/M5 Clutch, SS Shift Knob
    Suspension & Brakes: TC Kline True Match Coilovers 500f/500r w/ adjustable camber plates, Racing Dynamics sways, Custom front sway endlinks, ATE fluid, UUC/Willwood BBK 6 piston f - 4 piston r , Slotted E46M3 Rotors, Stainless Lines, Strong Strut, IE Subframe & adjustable rear trailing arm bushings
    ICE & Misc: Projector Z's w/DDE & 5k HID, 19'' Gold HRE C20's, Custom Aux pwr outlet, footwell lighting, ACS Splitters, Areo Sideskirts, Custom gauge pods, Z8 Start, Pioneer AVIC Z3, Clarus Components, 10" RE Sub in a Mister-X Enclosure, Alpine PDX 4X150 + 1X600 Amps
    Coming soon: and a visit to Randy Forbes

  12. #12
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    Quote Originally Posted by clintjg View Post
    You may notice that with the UUC shifter, the bottom of the selector rod is so long that it may contact the quibo when installed in the car.
    Actually I don't think that is going to be a problem. There is a riser cup included with this setup to raise it up. Question though for you Clint. Did you get the kit for the M Coupe or the E46? I ended up with the E46 set up and the length is not that long. I talked to Rob about that and he says that it is due to the difference in the internals between the 5 and 6 speed. The UUC shifter is a lot longer when compared to what came on the original 6 speed but not a lot of difference between what was stock on our cars. If you got the M Coupe kit, your throw I'm guessing is WAY short.
    1999 M Coupe Boston Green, Beige, H&R/Bilsteins, Underdrive Pulleys, Euro 6 speed, UUC SSK and Randy Forbes in the back
    2002 2.5 Z3 roadster Oxford Green, auto, all stock
    2013 Ram 3500 Crew Cab Dually 385 HP, 850 ft lbs torque at 1600 rpm, all stock and staying that way
    2004 Mini Cooper Chili Red, daily driver, modified almost daily

  13. #13
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    I had the UUC Z3M short shifter in the car for years before doing the swap. IIRC 1st and 2nd were unreachable due to the bottom of the shift lever hitting the guibo.

    At the time I needed a solution that would allow me to drive the car, but I also wanted something that shifted as smoothly as possible. So I used a different shifter that was adjustable, as well as a very heavy shift knob and a weighted selector rod.

    With all of the extra weight providing momentum on each shift, even the notoriously hard to impress Mr. Stygar once commented on how smooth it felt between gears.
    2002 Alpine White w/ Black 368 (<OO \(||][||)/ OO>)
    Power: Custom Exhaust w/ High Flow cats, CSL headers, built, low-compression Supercharged and aftercooled S-54, ViPEC standalone ECU, Vortech V2 Si trim
    Driveline: Euro 6 speed, 3.64 diff w/ 40% Lockup, Rogue Octane SSK, UUC Red TME kit, UUC Stage 3 LTW Flywheel/M5 Clutch, SS Shift Knob
    Suspension & Brakes: TC Kline True Match Coilovers 500f/500r w/ adjustable camber plates, Racing Dynamics sways, Custom front sway endlinks, ATE fluid, UUC/Willwood BBK 6 piston f - 4 piston r , Slotted E46M3 Rotors, Stainless Lines, Strong Strut, IE Subframe & adjustable rear trailing arm bushings
    ICE & Misc: Projector Z's w/DDE & 5k HID, 19'' Gold HRE C20's, Custom Aux pwr outlet, footwell lighting, ACS Splitters, Areo Sideskirts, Custom gauge pods, Z8 Start, Pioneer AVIC Z3, Clarus Components, 10" RE Sub in a Mister-X Enclosure, Alpine PDX 4X150 + 1X600 Amps
    Coming soon: and a visit to Randy Forbes

  14. #14
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    Looking forward to this. Subscribe.
    -Phil

  15. #15
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    ^What he said

  16. #16
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    ^ what they said
    2006 530xiT [02/15/14]
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    1995 M3 Cosmo [10/28/12][sold: 2/xx/14] // 1997 528i [10/26/10][sold:10/13/12] // 2002 325i [sold] // 1990 325i [sold] // 2000 323i [crashed]

  17. #17
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    So there have been a couple of delays in getting this done but forward progress is being made.

    1. The main delay is getting the driveshaft back. For some reason, finding parts to rebuild it is turning out to be difficult for them. Hopefully some good news soon.

    2. I finally got the output shaft seals and diff cover gasket. Diff is mostly put back together and would be done already but ran into problem #3.

    3. The instructions I got from UUC on modifying the aluminum carrier were mostly correct except for one minor detail. They told me to grind out the entire cup inside. Their kit now has no where to sit ans when I called them, they said, "Oh ya, you should have left some there." So off I went. I needed to add a bead of weld back on to the carrier, grind out part of the weld to make a new shelf. It now looks ugly but it is fully functional again. I have now added JB Weld to fill in the ugly (cosmetic fix only) and after I finish grinding everything down and paint it, she will look pretty again.

    4. The clutch kit did not come with an alignment tool. Fortunately my buddy has a machine shop at his disposal and had 1 made.

    5. I am not sure if anything has been changed prior to the purchase of my car. The flywheel looks to be an aluminum one, the part number looks to be dremeled on. If someone can confirm that this is stock or aftermarket, I would be in your debt. Regardless, it is in great shape.



    The new clutch. It is made by the OEM supplier and looks identical to what came out of my car except it has some meat to it. The old one was quite thin. Definitely a good call to change it.





    This is how the transmission comes.





    Since it was so clean, nicely primed, I couldn't install it yesterday and I had a can of spray paint, I painted it. This is only coat 1, coat 2 is sooo nice.





    While i was rattle can happy, i scrubbed down the front cross brace and gave that a fresh look. Hopefully today, we will get the motor mounts changed, the new clutch and associated parts installed, the transmission and linkages installed, the rear diff in and then just be waiting on the driveshaft.
    1999 M Coupe Boston Green, Beige, H&R/Bilsteins, Underdrive Pulleys, Euro 6 speed, UUC SSK and Randy Forbes in the back
    2002 2.5 Z3 roadster Oxford Green, auto, all stock
    2013 Ram 3500 Crew Cab Dually 385 HP, 850 ft lbs torque at 1600 rpm, all stock and staying that way
    2004 Mini Cooper Chili Red, daily driver, modified almost daily

  18. #18
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    Man you got Z fever pretty bad. It feels like it was just a few months back when you joined asking about saving a coupe... and now you have a roadster as well!

  19. #19
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    Yup. "Saved" that one for my parents. Much nicer car than I was expecting. That would make an excellent DD.

    Lots done this afternoon. New pilot bearing, clutch, TOB, ball pin and spring clip were replaced and finished up the shifter carrier. Ready for installation.

    After seeing how tight the UUC delrin bushings are, this seemed like the best approach to installing the transmission into the car. I am replacing the shifting arm bearing as well. This will be put on the carrier and then installed.



    Installation is not for the faint of heart. There were 3 of us working on it and the other 2 do this for a living. I can't say it was bad but if my car was on jack stands and I were attempting this on my back, I might be a little cranky. I am sure for those who have done transmissions before it wouldn't be that bad. The worst was getting the starter bolts lined up. The shifting mechanisms went in just fine although I did miss the alignment on the shifter selector rod by a degree or 2 so my shifter initially sat a little more toward 6th than center. A little heat and a little bend and it is back to the middle. Hopefully the group buy will have enough people for UUC to include the DSSR and this will be replaced at that time. The new transmission cross member bolts right into place with stock bolts and mounts. The original slave is used but the metal bracket will need to be ground out just a little to clear the transmission. Sorry for the bad pic.



    The diff got put back into place and filled with Amsoil 75W-140. Already just spinning the tires on the lift it feels so much more locked up.

    The first driveshaft place was a bust. We picked it back up today and it is going to an independent high performance shop who will make me a new tube, replace all u joints with serviceable ones and high speed balance it. He says 1 day. Let's hope. If that is true, I could be driving by Friday.
    Last edited by Wertles; 09-12-2012 at 06:45 PM. Reason: Automerged Doublepost
    1999 M Coupe Boston Green, Beige, H&R/Bilsteins, Underdrive Pulleys, Euro 6 speed, UUC SSK and Randy Forbes in the back
    2002 2.5 Z3 roadster Oxford Green, auto, all stock
    2013 Ram 3500 Crew Cab Dually 385 HP, 850 ft lbs torque at 1600 rpm, all stock and staying that way
    2004 Mini Cooper Chili Red, daily driver, modified almost daily

  20. #20
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    I thought painting the trans is a bad idea since the paint prevents the heat from dissipating <sp> thus reducing it cooling capability.

  21. #21
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    Quote Originally Posted by Wojtek79 View Post
    I thought painting the trans is a bad idea since the paint prevents the heat from dissipating <sp> thus reducing it cooling capability.
    I can't believe that matters--there is a lot of surface area there. It's not an automatic, where trans cooling is an issue anyway, and the paint is not much of an insulator when you get right down to it. Don't know that I would heat wrap it, but a little primer and color isn't going to affect it.

    What's the cost of fabricating a new shaft altogether--kind of thought it was taking way too long with the original guys. Did you muscle it in, or use a trans stand? I don't think this a job for jack stands--a lift is definitely called for here. Are you taking more process pics and notes for the group?
    Last edited by Mr Bingley; 09-14-2012 at 06:52 AM. Reason: Automerged Doublepost

  22. #22
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    Quote Originally Posted by Wojtek79 View Post
    I thought painting the trans is a bad idea since the paint prevents the heat from dissipating <sp> thus reducing it cooling capability.
    I have heard both sides of the story and there are decent arguments for both. Every car build show always shows the high performance transmission as painted so I figured it can't be all that bad. If this transmission had come unprimed, it would have stayed that way. Since it already had primer, another layer of black wasn't going to make any difference.

    Quote Originally Posted by Mr Bingley View Post
    What's the cost of fabricating a new shaft altogether--kind of thought it was taking way too long with the original guys. Did you muscle it in, or use a trans stand? I don't think this a job for jack stands--a lift is definitely called for here. Are you taking more process pics and notes for the group?
    It was taking too long. It would have been a one day job if my tube wasn't bent and twisted. Since I went to a corporate place, upper management said no to the rebuild. I didn't try to fight, I just picked it up and went to the place I wanted to go with first. I dropped it off yesterday and spoke directly with the guy who will be doing the work. He will try to work on it today but he has to make a few parts so it will fit on to his balancer. Worst case scenario, it will be done early next week.

    I really haven't taken more pictures than what I have posted. Vinci has a great write up on pulling the transmission and changing a clutch so I would rather people reference that for info and pics of the process. I have just been trying to gets pics that are specific to this build and post them. Honestly, this has been so piece meal because even though you try and plan for everything, there is always a part or gasket that you should replace while you are there and waiting for them to come is the hassle. I'd rather have this swap take 3 weeks the right way than 2 days the wrong way. At the end of this, I will list all the parts I think should be changed while doing this job so the next guy is prepared.
    Last edited by Wertles; 09-14-2012 at 08:36 AM. Reason: Automerged Doublepost
    1999 M Coupe Boston Green, Beige, H&R/Bilsteins, Underdrive Pulleys, Euro 6 speed, UUC SSK and Randy Forbes in the back
    2002 2.5 Z3 roadster Oxford Green, auto, all stock
    2013 Ram 3500 Crew Cab Dually 385 HP, 850 ft lbs torque at 1600 rpm, all stock and staying that way
    2004 Mini Cooper Chili Red, daily driver, modified almost daily

  23. #23
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    Did you keep the stock 3:23 gears in your diff, or did you go a little (or a lot) lower? The 6th gear is supposed to drop around 500rpm over our old 5th.
    -Donny

  24. #24
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    Quote Originally Posted by Wertles
    Since it was so clean, nicely primed, I couldn't install it yesterday and I had a can of spray paint, I painted it. This is only coat 1, coat 2 is sooo nice.

    While i was rattle can happy, i scrubbed down the front cross brace and gave that a fresh look.
    Did you use any particular paint? Any rust stopper as base? I would be concerned that it will start flaking in a year otherwise.

  25. #25
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    Quote Originally Posted by KeysCoupe View Post
    Did you keep the stock 3:23 gears in your diff, or did you go a little (or a lot) lower? The 6th gear is supposed to drop around 500rpm over our old 5th.
    -Donny
    This is a sticky question. Here is my thought on the whole differential ratio thing. As a disclaimer, i have never had in my car nor have driven any other car with anything but stock ratios. Please, no one take offense on your selection of gear ratio. I am sticking with the stock 3.23. Here is my reasoning. Gear selection should be based on how you use your car. First, I like to go on long trips with the wife. I want to drop 500 rpm on the highway. Second, I have yet to see any concrete, ie. 0-60 or 0-100 times comparing stock vs. 3.73 differential. Yes, you will have quicker acceleration in each gear, but if you need to add an additional shift in to reach that speed, any time gained by the ratio change may be negated by that shift. I don't know this for fact, just my assumption. Third, if I ever get to FI, this ratio will be what I want anyway. Fourth, this is a Motorsports diff compared to the standard diff. I did not know that before tearing into it, it is a nice surprise. It is a 4 clutch system from the factory as compared to the 2. Jonathan can explain it much better than I can. At least if I decide to sell it now, I can buy a used diff, rebuild it and still have money in my pocket.

    Quote Originally Posted by Wojtek79 View Post
    Did you use any particular paint? Any rust stopper as base? I would be concerned that it will start flaking in a year otherwise.
    This is Rustoleum professional paint. A dollar more a can and I have had great luck with it over the past few years. If it flakes off in a year, who cares. If people can see it, i will assume that it will be a situation that flaking paint will be the least of my concerns.
    Last edited by Wertles; 09-14-2012 at 05:11 PM. Reason: Automerged Doublepost
    1999 M Coupe Boston Green, Beige, H&R/Bilsteins, Underdrive Pulleys, Euro 6 speed, UUC SSK and Randy Forbes in the back
    2002 2.5 Z3 roadster Oxford Green, auto, all stock
    2013 Ram 3500 Crew Cab Dually 385 HP, 850 ft lbs torque at 1600 rpm, all stock and staying that way
    2004 Mini Cooper Chili Red, daily driver, modified almost daily

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