I'm getting my ducks in a row to put a 6-speed into my M50 E34, either a 420G or 37BZ. Doing lots of homework right now on the former, but a few objective data points still elude me, and a few subjective issues always welcome more opinions.
Objective:
1. With OE parts, will an S54 friction disk work with an S52 flywheel and pressureplate? If so, what throwout bearing?
2. Apart from the M70/S70 (I had this on my E34 544iT), are there any OE, or at least OES (Sachs, LUK, Valeo...) sprung-hub disks with later 420G spline fitment? According to this, corroborated elsewhere, S52 splines are 10x1-1/8" while S54/M60/M62/S62/M70/S70 are 10x1-3/8".
3. S54 starter has a different PN than other x5x. Is it actually different in any meaningful way?
Subjective:
1. I know DMF wear out eventually, but what are the odds of premature failure, if bought brand new?
2. What's your opinion of S54 flywheel weight?
3. "Good, cheap, fast; pick two." Suppose you pick Good (reliable) and Cheap, don't need it to hold much power, prefer OE feel (no 6-puck kevlar/ceramic on/off switches please), slightly prefer LWFW, strongly prefer no SAC; what would be your setup for this application?
Last edited by moroza; 04-02-2019 at 11:57 PM.
Wow, that's a lot of miss-matched parts trying to make it work, not sure if it is worth the troubles.
Valeo has a full kit, and it is a known good replacement for the twin mass flywheel, and comes with all you need. Most places like Pelican part dot com sell them for a reasonable price. No need to mess with starters, ect.
Lastly what do you plan on doing with the car? That can also determine what type of clutch to put in.
If you are going to stick with the Twin Mass Flywheel, never put a new clutch on an old one, just replace it.
Darin
Current:
16 220i Active Tourer Platinsilver MET (C08)/Dakota Black (PDSW), P7ACA, P7LDA, P7LHA, P9BDA, 6sp Manual - Wife's new toy!
05 325it Electric Red(438)/Gray(N6TT) ZCW, ZSP 5sp Manual Back set cover, trunk mat, Euro Infra-Rot front windshield, and mud flaps! Mr. Wagon My new Winter car.
05 M3 Imolarot II(405)/Gray(N5TT) ZCW, ZPP 6sp Manual C.F. Lip, CSL diffuser, SSK, Euro Infra-Rot front windshield and a trunk liner! Mr. Go_Fast Stored for the Winter
Past:
95 318is Montreal Blue Met (297)/Beige(K1SN) RIP, killed by an Idiot.
84 M535i gray market Burgandy Rot Met/Black Leather Lowered by Intrax on bilies, poly everywhere, B&B cat back system, K&N, and a hitch! Da Beast - Still running w/400k+!
91 316i euro Tizianrot/Gray cloth - E-36 w/M-40 RIP, but great on gas! Best was 38 MPG
82 528i euro Saphire Blue Met/Blue Leather RIP
79 525 euro Green/Green RIP
79 318 Silver/Black - The first one that got it all started
M-Flight Member
I'm no stranger to mix-n-match builds; my previous E34 Touring had an M62, 420G, M70 clutch with modified slave, E32 then E31 diff...
My plans are to keep the M50 or possibly replace with stock-ish M52 or S52, so no big power. Later I want to put in a lightly tuned (~200hp/300ft-lb) Mercedes OM606, but that's going to involve a custom flywheel so I'm not worried about that yet. Stock 240mm clutch is plenty for now.
I can get a new LUK DMF with matching Valeo solid clutch for $550; is that the kit you mean? Or I can get a Gripforce SMF/sprung kit plus $70 Sachs throwout bearing for $300. Or, my preferred option, buy an aftermarket SMF for ~$150 and add a Sachs clutch kit (~$250?), but I've yet to figure out what clutch to use (that's question #2).
Actually I am talking about the Single mass Flywheel kit from Valeo, it would allow the motor to rev freely, and ditch couple of pounds in weight. I was never a fan of the TMF/DMF, for they cannot take a lot of abuse.
Darin
Current:
16 220i Active Tourer Platinsilver MET (C08)/Dakota Black (PDSW), P7ACA, P7LDA, P7LHA, P9BDA, 6sp Manual - Wife's new toy!
05 325it Electric Red(438)/Gray(N6TT) ZCW, ZSP 5sp Manual Back set cover, trunk mat, Euro Infra-Rot front windshield, and mud flaps! Mr. Wagon My new Winter car.
05 M3 Imolarot II(405)/Gray(N5TT) ZCW, ZPP 6sp Manual C.F. Lip, CSL diffuser, SSK, Euro Infra-Rot front windshield and a trunk liner! Mr. Go_Fast Stored for the Winter
Past:
95 318is Montreal Blue Met (297)/Beige(K1SN) RIP, killed by an Idiot.
84 M535i gray market Burgandy Rot Met/Black Leather Lowered by Intrax on bilies, poly everywhere, B&B cat back system, K&N, and a hitch! Da Beast - Still running w/400k+!
91 316i euro Tizianrot/Gray cloth - E-36 w/M-40 RIP, but great on gas! Best was 38 MPG
82 528i euro Saphire Blue Met/Blue Leather RIP
79 525 euro Green/Green RIP
79 318 Silver/Black - The first one that got it all started
M-Flight Member
I usually prefer a solid lightweight flywheel with a sprung clutch, so that'd be my choice outright, but I've heard mixed reports about how noisy it is with an S54. Would you expect an M50 with the same kit to be quieter, because it's a milder motor with a shorter stroke, or louder, because an S54 is perhaps better balanced from the factory?
My 544 had the UUC V12 flywheel (~7kg instead of ~19), and I loved how it woke up the engine. It made a little noise, not bad and totally worth it. But my 91 Ford 7.3 diesel's flywheel is an example of going too far - it sounds like hell below ~1500RPM regardless of gear. The response is unnecessarily excellent and the noise is really annoying. Not sure what to expect from an M50.
Last edited by moroza; 04-04-2019 at 03:43 PM.
I have heard a couple of guy complain with it on a M54 motor being a little chatter, but it is hit or miss it seems. I think they didn't understand that a solid flywheel needs a little more slipping of the clutch than a TMF/DMF.
I am due a clutch in the wagon, as it is start to shudder from the TMF going bad, but at 140k it is to be expected. I also want to do a 6-speed swap in at the same time, driving the autobahn with a 1:1 5th gear really sucks at times.
Darin
Current:
16 220i Active Tourer Platinsilver MET (C08)/Dakota Black (PDSW), P7ACA, P7LDA, P7LHA, P9BDA, 6sp Manual - Wife's new toy!
05 325it Electric Red(438)/Gray(N6TT) ZCW, ZSP 5sp Manual Back set cover, trunk mat, Euro Infra-Rot front windshield, and mud flaps! Mr. Wagon My new Winter car.
05 M3 Imolarot II(405)/Gray(N5TT) ZCW, ZPP 6sp Manual C.F. Lip, CSL diffuser, SSK, Euro Infra-Rot front windshield and a trunk liner! Mr. Go_Fast Stored for the Winter
Past:
95 318is Montreal Blue Met (297)/Beige(K1SN) RIP, killed by an Idiot.
84 M535i gray market Burgandy Rot Met/Black Leather Lowered by Intrax on bilies, poly everywhere, B&B cat back system, K&N, and a hitch! Da Beast - Still running w/400k+!
91 316i euro Tizianrot/Gray cloth - E-36 w/M-40 RIP, but great on gas! Best was 38 MPG
82 528i euro Saphire Blue Met/Blue Leather RIP
79 525 euro Green/Green RIP
79 318 Silver/Black - The first one that got it all started
M-Flight Member
Bookmarks