A few bits and pieces and a trip to Spa - New Windscreen

[Ed Doe]

ive got 100 CELL race cats.... fails the MOT every single year, such a pain in the ass

Love the new pipes! youve really created something special here mikey..... like myself weve invested so heavily, and created something such high performance i now find i can afford its replacement and im stuck here unless i want to spend 100k plus!!!

I've also got 100cell race cats too with the same issue, they only really work when roasting hot!

Op, forget what the purists think, it's your car - I reckon it's awesome 8)

 

[Mikey_Boy]

On some levels, I’m happy to hear that others have been having emissions issues….. :? I was surprised how cheap (relatively) the OEM catalyst was from a dealer. Thankfully, it sorted the emissions issue straight away

Thank you again for the kind words - as BeeDub rightly says, what do you replace a Z4 with? It’s something I have wrestled with for a while now - I love the idea of a Porsche GT4, but I can’t justify the money sat in my garage or the risk of someone taking me out on a trackday.

The Z4 is soooooo much fun and a really rare sight these days and so much potential to take a good car and make it great for not an enormous amount of cash.

 

[Mikey_Boy]

So - the last update…. Change of suspension from Bilstein to Intrax!!

Those of you who have read the whole thread will know I have had a decent re-work of the existing suspension from OEM to Bilstein that has served me extremely well, using loads of help on here - thank you again Exdos!!

Just to be clear, there is absolutely nothing wrong with the Bilstein suspension - it’s served me very well on road and track (and yes, the spring and damper kit is coming up for sale!). I wanted to go to the next level of springs and dampers and see what all the fuss was about.

In short, the Intrax suspension is fantastic. I answered a few questions from the Intrax folks on the car and it’s intended use so they could tailor the package. It’s a little controversial, but I asked for the springs and dampers to be set up for use with 19” wheels as I am running OEM CSL wheels on the road and 19” Apex ARC-8 for track work so I will be selling my OEM 18” 224s soon as well…

The quality of the damping is phenomenal and that translates into a super ride quality on the road. Where the Bilstein has 10 clicks of adjustment, the Intrax has 50 clicks so you could play all day. It doesn’t turn your Z4M into a Citroen for a pillowy smooth ride, but what it does do is smooth out a lot of the bumps at lower speeds where the Bilstein suspension could sometimes be a bit crashy and keeps high speed composure too. The anti roll (ARC) is something like black magic honestly with the car staying extremely flat during cornering.









The only 2 disappointments on the Intrax being:

1. No brackets for the brake lines and sensor wiring - quite a surprise honestly. In fairness, I didn’t ask about this when I ordered and once I noticed, I quickly made up a couple of brackets for the job.
2. Adjustment for the rear dampers is awkward as it’s on top of the damper in the rear wheel arch - I have bought a scissor jack to raise the car up to get access to this

I had the suspension installed and set up at a company called Suspension Secrets near Knutsford - extremely knowledgeable and helpful on the set up which is now as follows:

Front Camber: -2.7 degrees
Front Toe: 0.5mm toe in
Front Right Castor: -8 degrees
Front Left Castor: -8.5 degrees
(No more pulling to the left!! Hurrah! The guys at suspension secrets confirmed that the GT4 teams had this castor difference side to side)

Rear Camber: -1.8 degrees
Rear Toe: 1mm toe in



I have yet to try this set up on track but it feels very tight on the road so looking forward to getting some decent miles done after the salty winter months are behind us…

 

[Beedub]

mikey , please consider put the strut tower reinforcement plates in , ive seen with my own eyes at my shop a few track suspended z4 where the strut tower tops have deformed due to the smaller foot print of the new top mount concentrating load and ballooning the tower. its really cheap insurance , car looks SO special. what a thing you've created here.

 

[Mikey_Boy]

Thanks Beedub
It’s why I went for a separate spring and damper set up from Intrax at the rear - you can’t see it in the pictures, but there’s a large lovely titanium mounting plate on top of the damper - hopefully that should be enough?

 

[RedUn]

For the fronts

OEM Steel plates available to sit between the intrax top mount and the body.

The intrax do look lovely, I'd be tempted by them over my KWs if I did it again!

Shame about no brackets for the brake hoses etc

 

[TomK]

Looking great Mikey 8)
Beedub makes the point well, solid top mounts can deform/crack the strut towers (actually mine cracked with the plates on but nothing a little welding couldn't fix, deformation is a bigger issue). If you mark it up carefully I'd imagine you could get away without doing the alignment again.
part# 31312489795
Planning a trip to spa/ring next year, will let you know, would be good to catch up again there.

 

[1536Z4]

Great looking car with very nice upgrades .

 

[Mikey_Boy]

Looking great Mikey 8)
Beedub makes the point well, solid top mounts can deform/crack the strut towers (actually mine cracked with the plates on but nothing a little welding couldn't fix, deformation is a bigger issue). If you mark it up carefully I'd imagine you could get away without doing the alignment again.
part# 31312489795
Planning a trip to spa/ring next year, will let you know, would be good to catch up again there.

Oh wow - every day is a school day! Thank you all for the top tip - I had never considered the fronts as an issue…. :?

I’ll get some plates ordered and fitted in the Spring - gentle miles over the winter if the weather permits!

It would be great to catch up again Tom!

Now I’m curious about cams to make that airbox work properly…. :evil:

 

[Beedub]

Here is the plates in situ.

As you can see they place the force of these stiffer dampers across the complete top, ive got some pretty scary pics of the deformation ive seen on other cars, i would like to post but im alittle concerned about breaching trust... Between these plates and the Strut Brace ( doing the same from top ) i'm certain you wont see an issue.... Gt4s have been known to complete break this piece out lol which is bonkers. Absolutely cheap insurance, road miles are not going to cause an issue, but if you hit a decent pot hole, it could cause the killer blow, so be careful.

 

[Beedub]

KW clubsport owners, have you guys noticed that the wheel appears to have lost wheel travel ?? One of my front wheel often hangs in mid air on uneven ground , lmao! guessing its a stiff suspension thing it looks mad when it happens.

 

[RedUn]

KW clubsport owners, have you guys noticed that the wheel appears to have lost wheel travel ?? One of my front wheel often hangs in mid air on uneven ground , lmao! guessing its a stiff suspension thing it looks mad when it happens.

Yep, stiff front arb :evil:

 

[Beedub]

mikey,

can i also point out, your caliper anti rattle plates are on backwards, they are non functional in this orientation and allow excessive pad movement which leads to funny wear pattern on the pad and rotor / strain on those lower pistons. Compare your pic, to mine to see correct fitting, also linked the official AP fitment from the schematics.

 

[Mikey_Boy]

mikey,

can i also point out, your caliper anti rattle plates are on backwards, they are non functional in this orientation and allow excessive pad movement which leads to funny wear pattern on the pad and rotor / strain on those lower pistons. Compare your pic, to mine to see correct fitting, also linked the official AP fitment from the schematics.

Thank you Beedub - that’s an excellent spot - I appreciate you pointing that out. 8) This is what happens when work takes over your life and you don’t get time to check some of routine stuff carried out on your car by somebody else.

It’s on the list to check and change as needed….

 

[BMWZ4MC]

KW clubsport owners, have you guys noticed that the wheel appears to have lost wheel travel ?? One of my front wheel often hangs in mid air on uneven ground , lmao! guessing its a stiff suspension thing it looks mad when it happens.

Yup, front and rear. Mine is often a tripod when negotiating steep driveway entrances etc.

 

[BMWZ4MC]

…Thank you again for the kind words - as BeeDub rightly says, what do you replace a Z4 with? It’s something I have wrestled with for a while now - I love the idea of a Porsche GT4, but I can’t justify the money sat in my garage or the risk of someone taking me out on a trackday.

A V6 Lotus Exige is on my list as my next car, but it will be as well as (not instead of) my Zed. I just need to stop spending money on frivolous things (wedding, baby, new house etc) so I can buy one

 

[buzyg]

Nice to read that you enjoyed Spa. I took my ///MR there in 2011. Fabulous place. Don't tell any one, but I ran out of petrol and had to be towed back to the pits.

 

[Beedub]

Nice to read that you enjoyed Spa. I took my ///MR there in 2011. Fabulous place. Don't tell any one, but I ran out of petrol and had to be towed back to the pits.

haahahahah ... awesome, lol

 

[beanie]

Now I’m curious about cams to make that airbox work properly…. :evil:

Crest Automotive had an offer on a little while ago for Schrick cams, might be worth a call to see if it’s still on. If I ever suffer cam wear/follower flattening I’ll fit some, but given the limited gains for such a hefty outlay, I’m in no rush!

 

[Mikey_Boy]

Nice to read that you enjoyed Spa. I took my ///MR there in 2011. Fabulous place. Don't tell any one, but I ran out of petrol and had to be towed back to the pits.

Spa was simply fantastic - I have been lucky enough to go there a few times with work in the past so to be able to drive it was real bucket list stuff - can’t wait to get back there…!

Now I’m curious about cams to make that airbox work properly…. :evil:

Crest Automotive had an offer on a little while ago for Schrick cams, might be worth a call to see if it’s still on. If I ever suffer cam wear/follower flattening I’ll fit some, but given the limited gains for such a hefty outlay, I’m in no rush!

For sure it’s the law of diminishing returns, but I’d love to squeeze just a bit more out of the engine as I know there’s more there to come - I know it’s easier and better hp/£ with super charging, but I want to keep this car N/A for that throttle response and old school feel.

It’s either cams or a V10…..