F8X M3/M4 CF Drive shaft mod

[TheElite///M3]

Hi I’m waiting on my driveshaft and found a shop to cut/weld/balance. Will try my first documentation to help
the community. Will be also changing all motor mounts/oem guibo/racing diffs 3.95/mounts. Pretty much whole drivetrain refresh in terms of mounting points. I cant wait to report on NVH since this build is almost at 200k mi.

Glad to be part of this community with this platform, shocking how much is interchangeable from e30-f8x maybe even g.

-Josh

[Corradoloco]

I did mention “crusty” scale lol, before I install it I’ll take better measurements promise hahaha

[usdmej]

Wasn't Slonik trying to claim it's only 1-2 lbs lighter than stock? Lol.

seems like a lot has been lost in translation, it doesnt help they mentioned converting a mazda RX8 driveshaft and threw in weights for that too

e46m3 driveshaft weight (with cv joint) - 8.5kg (18.7lbs)

F8x cf driveshaft (with joint also, but different type, looks lighter) - 7.6kg (16.7lbs)

converted with rx8 cf driveshaft
6070g (13.4lbs)

so if i've got little bit more than 2kg drop on rx8 driveshaft, i don't think that you can get anything less than 7.5kg on f8x, maybe even heavier.

.

[Slonik]

Wasn't Slonik trying to claim it's only 1-2 lbs lighter than stock? Lol.

m4 shaft weight 16.7lbs, so when he got 12 lbs on his scales, i'd recommend to use some more accurate scales. closest supermarket with vegetables scales waiting

[EthanolTurbo]

On my crusty scale …
Stock M3 shaft w/ cv joint = 19 lbs
Stock M4 shaft w/ cv joint = 12 lbs
Modded M3 CF shaft w/ cv joint = 11 lbs

Wasn't Slonik trying to claim it's only 1-2 lbs lighter than stock? Lol.

[Corradoloco]

stock m3 shaft weight also includes carrier bearing.

[0-60motorsports]

On my crusty scale …
Stock M3 shaft w/ cv joint = 19 lbs
Stock M4 shaft w/ cv joint = 12 lbs
Modded M3 CF shaft w/ cv joint = 11 lbs

Awesome thanks for posting!

[Obioban]

On my crusty scale …
Stock M3 shaft w/ cv joint = 19 lbs
Stock M4 shaft w/ cv joint = 12 lbs
Modded M3 CF shaft w/ cv joint = 11 lbs

That certainly seems like a bigger weight drop than we were expecting!

[Corradoloco]

On my crusty scale …
Stock M3 shaft w/ cv joint = 19 lbs
Stock M4 shaft w/ cv joint = 12 lbs
Modded M3 CF shaft w/ cv joint = 11 lbs

[0-60motorsports]

Anyone made any progress especially SMG Folks

[PipeUy]

The driveshaft arrived at Uruguay, probably going to wait to do it together with a Wavetrac and probably 4.10 gears but it's nice to have it here.

[George Hill]

I wonder what kind of MPG the S54 is capable of with that 8-speed and a modest diff ratio.

I don't want to muddy up this thread with 8HP stuff so maybe I'll start a dedicated thread, but to your question the 8th gear and 4.44 ratio is almost the exact same as a 420g 6th gear and 3.62. With the Turbo Lamik it is hard to keep it in 8th on the highway in automatic mode as any slight throttle causes it to downshift. Swapping to the 4.44 vs the 3.15 I had in it was night and day different but still not ideal. My car generally gets mid to low 20s pure fast highway.

[e46IX]

I wonder what kind of MPG the S54 is capable of with that 8-speed and a modest diff ratio.

[George Hill]

Hmm, man I was considering an 8hp after watching the aussies do it on their cars for my daily wagon. What's the trade off George?

Drivability is pretty crap. I mean its ok, but a daily driver you want to drive everyday doing mundane tasks I'd say its a lateral move from SMG, maaaaaybe even down grade.*

*I run a TurboLamik controller and their aftersales support is atrocious. I would never run or install into anyones car an HTG. CANTCU is not ready for MSS54 DMEs yet. MaxxECU (Standalone ECU) is working on their own 8HP protocol which I am looking at for another build. BUT if you are on a standalone (not just Maxx) then you can use a CANTCU as well

[enjoy_m3]

Depends on what you call a "thing" lol. It works, but not as good as a stock car and certainly not in an upgrade in all areas.




That I do, reason I can run a 4.44 diff ratio and am asking about driveshaft speeds.

Hmm, man I was considering an 8hp after watching the aussies do it on their cars for my daily wagon. What's the trade off George?