Meant to do this for a while and as I've got some time and done a fair few miles plus track days, I thought I'd post my thoughts on the work I've had done this year which might be useful to others considering the same route. It's on a 90k miler Z4M Roadster.
Firstly, everything that was replaced....
Suspension
- Bilstein B16 PSS10 suspension package
- Powerflex (All purple) - Control Arm rear bushes (lollipops), Front and Rear Anti Roll Bar bushes, Adjustable rear camber arms, Rear shock top mounts
- Lemforder Front control arms (OEM)
- Lemforder RTABs (OEM) used with existing limiters (from research I decided on this rather than Powerflex, plus I already had limiters)
- 4 x Lemforder upper and lower rear wishbone ball joints (OEM) - Powerflex do a replacement, but I chose to avoid as OE are ball joints and the Powerflex are not
- Lemforder Steering Tie / Track rods - both sides. Mine had play so needed doing. I nearly went BMW as I wasn't sure who was OEM but I ordered from BMW and Lemforder and they are exactly the same comparing side by side, down to the markings. So sent the BMW ones back and saved about £200.
- FAG tie rod bellows and BMW grease
- Lemforder Front and Rear droplinks (OEM)
- BMW Rear spring pads
- BMW Front shock tower reinforcement plates
- BMW front top mount axial bearings
- Every single fixing replaced from BMW (Too many to mention)
Subframe / Diff / Propshaft
- Subframe cleaned stripped and powder coated
- Powerflex Yellow subframe bushes - originals were starting to separate and needed replacing
- BMW diff mounting bush
- BMW diff output shaft seals / plates / all serviceable parts
- BMW diff input seals / plates / all serviceable parts
- Febi Bilstein Propshaft center bearing (99% sure OEM)
- Febi Bilstein Propshaft universal joint (or Guibo / Donut whatever you want to call it) (99% sure OEM)
- Millers CRX LS 75w140 NT+ Diff oil (Recommended so thought I'd give it a try)
- BMW fixings for all diff / prop / subframe parts possible (The diff carrier bolt mentioned above that is £16 is worth doing, an updated design that helps with the common M 'clunk'). Also diff oil plugs
Engine / Gearbox (+Inspection 2)
- Castrol 10w60 oil
- Mahle OX187D oil filter (OEM)
- BMW Coolant (Full flush)
- Castrol Transmax DEX3 Power Steering Fluid
- Mann cabin filter
- NGK DCPR8EKP spark plugs (OEM)
- BMW cam cover gasket - plus all rubber grommits / o-rings for spark plugs etc.
- BMW post cat o2 sensors x2 (Had an error code for bank 2 so replaced both)
- Hella 6PX 008 476-271 Throttle Position Sensors (OEM)
- INA Belt Tensioners / Idler pulleys / AC pulley (OEM)
- Contitech Drive belt + AC Belt (OEM)
- Redline MTL + D4 ATF gearbox oil (All the MTL topped up with D4 to the top - recommended by Opie and others)
- Wahler 462180D thermostat (OEM)
- BMW Water Pump (From leebmann24.de - a fair bit cheaper than from the UK but still BMW - still expensive though - there is no OEM part available unfortunately)
- All radiator / gearbox plugs, o-rings etc. from BMW
- All exhaust clamps replaced from i6 automotive (now ditched and ended up sleeving the exhaust where it meets the backbox as the flanges were rusted through)
- Vibratech Engine Mounts
- BMW rubber exhaust hangers
- BMW Fuel Filter / pressure regulator (Again from leebmann24, quite a bit cheaper than from the UK)
- Compression / leak test all ok - head gasket kit brought but will wait to replace for now
Brakes
- Custom brake cooling kit (From forum member Andre/Westersund)
- Motul RBF600 brake fluid
I've listed all the parts there as it may be useful for others looking to replace parts but want to save money buying from BMW when you can get the OEM part for sometimes a fraction of the price. I did a lot of research to make sure all parts that weren't from BMW were from the OEM so basically the exact same part without the BMW stamp on it. Safe to say I saved hundreds of pounds doing this, rough estimate around £600 minimum. Most OEM parts were from Euro Car Parts / Ebay sellers. All the bolts and fixings were from BMW however and there's no getting round these add up pretty quickly.
Luckily I managed to get the car to Darragh at Everything M3's in Banbury just before lockdown started so he had the car through most this period, working on putting it all together for me. In a nutshell, he did a great job, and is an all round great guy so I can highly recommend. (He also did my rod bearings but that's a separate post elsewhere!)
On the road
The handling is transformed which is to be expected from the old 90k parts that were on the car! It's sharper, tighter, sportier and so much grip and feedback. The PSS10 shocks offer 10 clicks of adjustment which are very nicely located on the bottom of the struts, so adjusting takes seconds....though you do have to get on the ground to adjust the rear struts, no biggie though. It just feels like a proper sportscar now, which is great for me as a weekend / fair weather car. However....!
There is a price to pay with all this extra added stiffness and feel, and this is not just the suspension but a combination of the Powerflex parts as well. It is a harsher ride on rough roads, no doubt about it. It rattles more, is noisier and not going to lie, it *CAN* get tiresome on bad roads, which around where I am, seem to be quite plentiful at the moment. The caveat to this is....it only ever bothers me when the roof is up and I have no music / radio on. When the roof is down or music is on it isn't an issue, probably because the rattles and creaks are downed out by the engine noise / road noise and it becomes a pleasure again and so enjoyable to drive. Another point to make is I am driving on 19" wheels with rubber band tyres which certainly don't help matters and to be fair, it's not a whole lot worse than the standard set up IIRC.
On a smooth road however, it's just fantastic, so much better than standard in every way and feels composed, quiet and highly chuck-able. I wouldn't change anything I've had fitted, feeling the car working underneath you rather than sloppy old rubber components is a revelation.
On the track
It's not fair for me to go into too much detail here, as a) I'm a bit of a track noob at the moment b) I don't really have a lot to compare to.
What I will say is, I've done some driver training, most recently at Millbrook Proving Grounds and it handled beautifully, the instructor commenting numerous times how well it was set up and on many of the tests how balanced and composed it felt. These are guys that drive high performance sportscars well in excess of the cost of mine so I felt was pretty high praise.
On track itself, well I've only managed a few days at Abingdon so far which is an airfield track so not a proper test. But for me as a relative new guy to this, the car gave me so much confidence to push and explore the limits and I never felt out of control or the car was going to spit me off. It is setup fairly conservatively at the moment but you can really push it before it starts giving out to understeer and any failings in handling now are purely down to the tyres (and my skill!). The change of direction and speed you can take through high speed corners is pretty staggering but the car gives you the confidence to be able to do it. I've had no scary snap oversteer or unpredictable moments and coupled with M-Track Mode (cheers Meeko!), it's a beast on a fast lap. Obviously traction fully off will be quicker but not quite at that point yet! I do think at some point brakes are going to need upgrading but that's for another time.
As a quick note, I did get the car corner weighted and set up properly after all the fitting was done which is well worth it. It did weigh in at a rather portly 1551kg though!
In conclusion, I can highly recommend doing a refresh when you get near 100k. Which probably shouldn't be a surprise! It's not cheap, but you'll definitely be missing out on performance on original components. The PSS10 also get's a big thumbs up, by far the best mod I've done hands down.
Feel free to ask any questions, otherwise apologies for a long winded post! Oh, just to add, the gearbox oil combo I used has made the gear change a lot slicker than previously with OEM fluid, can highly recommend that combination.
Firstly, everything that was replaced....
Suspension
- Bilstein B16 PSS10 suspension package
- Powerflex (All purple) - Control Arm rear bushes (lollipops), Front and Rear Anti Roll Bar bushes, Adjustable rear camber arms, Rear shock top mounts
- Lemforder Front control arms (OEM)
- Lemforder RTABs (OEM) used with existing limiters (from research I decided on this rather than Powerflex, plus I already had limiters)
- 4 x Lemforder upper and lower rear wishbone ball joints (OEM) - Powerflex do a replacement, but I chose to avoid as OE are ball joints and the Powerflex are not
- Lemforder Steering Tie / Track rods - both sides. Mine had play so needed doing. I nearly went BMW as I wasn't sure who was OEM but I ordered from BMW and Lemforder and they are exactly the same comparing side by side, down to the markings. So sent the BMW ones back and saved about £200.
- FAG tie rod bellows and BMW grease
- Lemforder Front and Rear droplinks (OEM)
- BMW Rear spring pads
- BMW Front shock tower reinforcement plates
- BMW front top mount axial bearings
- Every single fixing replaced from BMW (Too many to mention)
Subframe / Diff / Propshaft
- Subframe cleaned stripped and powder coated
- Powerflex Yellow subframe bushes - originals were starting to separate and needed replacing
- BMW diff mounting bush
- BMW diff output shaft seals / plates / all serviceable parts
- BMW diff input seals / plates / all serviceable parts
- Febi Bilstein Propshaft center bearing (99% sure OEM)
- Febi Bilstein Propshaft universal joint (or Guibo / Donut whatever you want to call it) (99% sure OEM)
- Millers CRX LS 75w140 NT+ Diff oil (Recommended so thought I'd give it a try)
- BMW fixings for all diff / prop / subframe parts possible (The diff carrier bolt mentioned above that is £16 is worth doing, an updated design that helps with the common M 'clunk'). Also diff oil plugs
Engine / Gearbox (+Inspection 2)
- Castrol 10w60 oil
- Mahle OX187D oil filter (OEM)
- BMW Coolant (Full flush)
- Castrol Transmax DEX3 Power Steering Fluid
- Mann cabin filter
- NGK DCPR8EKP spark plugs (OEM)
- BMW cam cover gasket - plus all rubber grommits / o-rings for spark plugs etc.
- BMW post cat o2 sensors x2 (Had an error code for bank 2 so replaced both)
- Hella 6PX 008 476-271 Throttle Position Sensors (OEM)
- INA Belt Tensioners / Idler pulleys / AC pulley (OEM)
- Contitech Drive belt + AC Belt (OEM)
- Redline MTL + D4 ATF gearbox oil (All the MTL topped up with D4 to the top - recommended by Opie and others)
- Wahler 462180D thermostat (OEM)
- BMW Water Pump (From leebmann24.de - a fair bit cheaper than from the UK but still BMW - still expensive though - there is no OEM part available unfortunately)
- All radiator / gearbox plugs, o-rings etc. from BMW
- All exhaust clamps replaced from i6 automotive (now ditched and ended up sleeving the exhaust where it meets the backbox as the flanges were rusted through)
- Vibratech Engine Mounts
- BMW rubber exhaust hangers
- BMW Fuel Filter / pressure regulator (Again from leebmann24, quite a bit cheaper than from the UK)
- Compression / leak test all ok - head gasket kit brought but will wait to replace for now
Brakes
- Custom brake cooling kit (From forum member Andre/Westersund)
- Motul RBF600 brake fluid
I've listed all the parts there as it may be useful for others looking to replace parts but want to save money buying from BMW when you can get the OEM part for sometimes a fraction of the price. I did a lot of research to make sure all parts that weren't from BMW were from the OEM so basically the exact same part without the BMW stamp on it. Safe to say I saved hundreds of pounds doing this, rough estimate around £600 minimum. Most OEM parts were from Euro Car Parts / Ebay sellers. All the bolts and fixings were from BMW however and there's no getting round these add up pretty quickly.
Luckily I managed to get the car to Darragh at Everything M3's in Banbury just before lockdown started so he had the car through most this period, working on putting it all together for me. In a nutshell, he did a great job, and is an all round great guy so I can highly recommend. (He also did my rod bearings but that's a separate post elsewhere!)
On the road
The handling is transformed which is to be expected from the old 90k parts that were on the car! It's sharper, tighter, sportier and so much grip and feedback. The PSS10 shocks offer 10 clicks of adjustment which are very nicely located on the bottom of the struts, so adjusting takes seconds....though you do have to get on the ground to adjust the rear struts, no biggie though. It just feels like a proper sportscar now, which is great for me as a weekend / fair weather car. However....!
There is a price to pay with all this extra added stiffness and feel, and this is not just the suspension but a combination of the Powerflex parts as well. It is a harsher ride on rough roads, no doubt about it. It rattles more, is noisier and not going to lie, it *CAN* get tiresome on bad roads, which around where I am, seem to be quite plentiful at the moment. The caveat to this is....it only ever bothers me when the roof is up and I have no music / radio on. When the roof is down or music is on it isn't an issue, probably because the rattles and creaks are downed out by the engine noise / road noise and it becomes a pleasure again and so enjoyable to drive. Another point to make is I am driving on 19" wheels with rubber band tyres which certainly don't help matters and to be fair, it's not a whole lot worse than the standard set up IIRC.
On a smooth road however, it's just fantastic, so much better than standard in every way and feels composed, quiet and highly chuck-able. I wouldn't change anything I've had fitted, feeling the car working underneath you rather than sloppy old rubber components is a revelation.
On the track
It's not fair for me to go into too much detail here, as a) I'm a bit of a track noob at the moment b) I don't really have a lot to compare to.
What I will say is, I've done some driver training, most recently at Millbrook Proving Grounds and it handled beautifully, the instructor commenting numerous times how well it was set up and on many of the tests how balanced and composed it felt. These are guys that drive high performance sportscars well in excess of the cost of mine so I felt was pretty high praise.
On track itself, well I've only managed a few days at Abingdon so far which is an airfield track so not a proper test. But for me as a relative new guy to this, the car gave me so much confidence to push and explore the limits and I never felt out of control or the car was going to spit me off. It is setup fairly conservatively at the moment but you can really push it before it starts giving out to understeer and any failings in handling now are purely down to the tyres (and my skill!). The change of direction and speed you can take through high speed corners is pretty staggering but the car gives you the confidence to be able to do it. I've had no scary snap oversteer or unpredictable moments and coupled with M-Track Mode (cheers Meeko!), it's a beast on a fast lap. Obviously traction fully off will be quicker but not quite at that point yet! I do think at some point brakes are going to need upgrading but that's for another time.
As a quick note, I did get the car corner weighted and set up properly after all the fitting was done which is well worth it. It did weigh in at a rather portly 1551kg though!
In conclusion, I can highly recommend doing a refresh when you get near 100k. Which probably shouldn't be a surprise! It's not cheap, but you'll definitely be missing out on performance on original components. The PSS10 also get's a big thumbs up, by far the best mod I've done hands down.
Feel free to ask any questions, otherwise apologies for a long winded post! Oh, just to add, the gearbox oil combo I used has made the gear change a lot slicker than previously with OEM fluid, can highly recommend that combination.
but seriously keep me posted. Dave's knocking it out of the park these days with a 210,000 mile c6 vette, it's a monster, but I think we might just have the edge on him (have to try rather hard mind!).
) but a diff refresh/change(?) is on my mind, I know who I'll be calling.
