F8X M3/M4 CF Drive shaft mod

[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

[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.

.

[Corradoloco]

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

[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

[EthanolTurbo]

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

RacingDiffs is garbage, don't waste your time.

[0-60motorsports]

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

Thanks Josh

[EthanolTurbo]

Update: at the driveshaft specialist now. He is doing the measurements and we will begin modifying it today. Should be done in a couple days. Progress!

This isn't a cheap job though. This place is charging about $775 labor and parts. I'm going to bite the bullet for the sake of data but will be trying another shop for future driveshafts. These guys know what they're doing so it's worth the initial hit I suppose. That puts total cost at around $1075 for me. I am using my old stock E46 M3 driveshaft as a donor but according to this thread the 330i driveshaft will work as well and is peanuts cost-wise.

Hoping to have this installed middle of next week.

[0-60motorsports]

Update: at the driveshaft specialist now. He is doing the measurements and we will begin modifying it today. Should be done in a couple days. Progress!

This isn't a cheap job though. This place is charging about $775 labor and parts. I'm going to bite the bullet for the sake of data but will be trying another shop for future driveshafts. These guys know what they're doing so it's worth the initial hit I suppose. That puts total cost at around $1075 for me. I am using my old stock E46 M3 driveshaft as a donor but according to this thread the 330i driveshaft will work as well and is peanuts cost-wise.

Hoping to have this installed middle of next week.

That's great if you could take detailed shots and measurements that'll really help me being thousands of miles away to get this mod done. $775 is steep including the donor so thank you for doing this.

[EthanolTurbo]

That's great if you could take detailed shots and measurements that'll really help me being thousands of miles away to get this mod done. $775 is steep including the donor so thank you for doing this.

It's not too bad honestly. Ideally $700-900 would be the sweet spot but about $1k for an OEM CF driveshaft is not a bad deal.

I will measure everything once it's complete.

[0-60motorsports]

It's not too bad honestly. Ideally $700-900 would be the sweet spot but about $1k for an OEM CF driveshaft is not a bad deal.

Yeah true. But here labor will be much cheaper so let's see if I can get it done or I'll have to ask someone in the States for a hand in getting it done there.

[Obioban]

That’s ~double what I paid to have my e60 M5 driveshaft shortened for the 6mt conversion 🤔

[EthanolTurbo]

That’s ~double what I paid to have my e60 M5 driveshaft shortened for the 6mt conversion 🤔

California labor ain't cheap. I fully expect the labor to be 30-50% less than what I paid in other states/countries. I will also shop around but wanted to get this done with a competent shop and test it out.

[e46IX]

RacingDiffs is garbage, don't waste your time.

Why do you say that? I was planning on using their refresh kit when doing my R&P swap. Owner seems knowledgeable and helpful from whatever questions I asked him.

[EthanolTurbo]

Why do you say that? I was planning on using their refresh kit when doing my R&P swap. Owner seems knowledgeable and helpful from whatever questions I asked him.

I just wouldn't put their junk parts into a diff when you can buy quality OEM parts and/or upgraded high quality aftermarket LSD units and get it done right the first time. Heard of a lot of failures with RacingDiffs junky parts.

[Bry5on]

California labor ain't cheap. I fully expect the labor to be 30-50% less than what I paid in other states/countries. I will also shop around but wanted to get this done with a competent shop and test it out.

I think it was Oceanside Driveline that I used to use back in the day. That was about twenty years ago though so YMMV!