Obioban's 2005 IR/IR Coupe

[Obioban]

Curious what motivated you to move away from the Ohlins if you were happy with the setup after adopting flat ride spring rates.

Ironically, it's how happy I am with the flat ride Ohlins that's making me move away from them. That said, I am selling them to a friend with a significant caveat-- if I regret my decision, he has to sell them back to me for the same price I sold them to him for.

To explain further...
Flat ride and the FCM spreadsheet have completely transformed my car for the better. It is faster, more comfortable, and more predictable. Thanks to the spreadsheet, I can actually make objective part choices and understand what I'm getting into without having the trial and error multiple spring and sway bar combos. After 15 years of own the car, I finally feel like I can make informed suspension parts decisions. It's been eye opening and wonderful in every possible way.

Flat ride is a huge break from conventional BMW aftermarket setups. If it wasn't stock on almost every car (including things like GT3 RSs), I probably wouldn't have tried it. Fat Cats is really working outside of the box, and the results... well, they're one of my favorite changes I've made to the car.

Fat Cats shocks are similarly outside of the box. But, the theories they're devised under similarly make sense to me. I love the idea of getting away from jacking down. The KBO looks to superior to Ohlins DFV. Adjustability isn't useful if you have shocks valved to your cars specifically corner weights and spring rates, and adds the ability to get it wrong (likely) and more possible points of failure. And, having a setup designed around flat ride should mean less shock stiffness is necessary (as flat ride causes the car to naturally settle faster).

Fat Cats has also set up a lot of winning cars, which gives me further confidence in the setup.

Basically, I've been absurdly happy with the changes to my car from following his spring theory-- enough so that I'm going out on a limb and tryin this shock theory as well... even though I'm exceedingly happy with my car as is. I'm hoping for a car that rides better, grips better, and handles better. That's what I got from their spring setup, and am hoping it extends to their shock setup, as well. If not, I can retreat back the the Ohlins and only be out money.

[Obioban]

This made my night!

How do you like the M3 with 275/40/17 NT01's?

So... multiple thoughts:

-my track mods are focused far more on cost minimization than speed maximization. I'm not racing, and the e46 M3 is slow compared to modern fast things no matter what, so I'm not trying to make the car the fastest thing out there. I like it to drive nicely (predictably and not managing temps) and keep costs as low as possible. So, that's the priority set.

-the NT01s fit really well into that mindset. They cheap, especially if you wait for sales, and last a long time. I got this current set for $100/tire, new, shipped! That's crazy cheap, IMO. Discount tire tends to have a large sale on them in late fall/early winter, and that's the time to buy IMO. In addition to the cheap purchase price, they seem to last a long, LONG time and don't get heat cycled out. I'm 9 events into these and they still feel good. They don't have any rain grooves anymore, so they're hydroplane on a light mist, but they're still going strong.

-17s are great because tires for them are cheaper

-17s aren't great because tire options are very limited in e46 m3 widths. You basically can get RE-71Rs (which I hated and used up in 2 events) or NT-01s. I like the NT-01s, but I'd like more options more.
(or slicks, but they don't last long enough for me to consider them)

-265 or 275 square is what I've been tracking for a decade+. Feels great. Can rotate for better life still.

-I don't like the ET25 offset. I know lots of people do, but, if you have a setup with the spring perch above the tire, I think the ET35 (with a 10mm spacer in the rear) setup is just better. Assuming you're not too low/stiff (many people who track are, imo), the et35 setup lets you have less static camber. Combined with more dynamic camber from the higher ride height and softer springs, you can dial your camber in by tire temps instead of setting to max to fit it under the fenders. This can be improved by increasing the caster on your camber plates and/or CSL kingpins (which I'm doing both). So, once these tires are used up, I'll probably sell this set and get a set of 17x9.5 et35s... assuming they clear the 996 calipers (they don't clear the brembo 355 calipers), which I'll have to verify somehow, and assuming I don't dislike these brakes once I try them on track.

-I wish there was a 265 wide 17" NT-01, as that's probably a better match for my car's current weight and that would fit more optimally on a 9.5" wheel.

[duracellttu]

Curious what motivated you to move away from the Ohlins if you were happy with the setup after adopting flat ride spring rates.

[S14]

The 17x10 Apexs fit with space to spare over these. I kind of want to try the 17 x 9.5 et35s, as I don't actually like the et25 setup.

17x10 et25 brake clearance:

This made my night!

How do you like the M3 with 275/40/17 NT01's?

[Obioban]

I finally made the decision to join you and jump from the TCK SA setup I have to the FCM stage 3. Been talking with Shaikh for the past couple of weeks about my setup. I went with flat ride spring but the dampers just could manage the increased spring rates so here I am.

Where did you end up sourcing the H&R set? I’m trying to find best pricing right now, so I can order and have them drop shipped to FCM. Were lead times bad?

ECS had a sale on them, so I hoped on it.

Took ~2 weeks to arrive.

[duracellttu]

And the H&R coilovers arrived, that I'll be sending off to Fat Cats Motorsports for reworking. I go back and forth between being super excited and feeling like I've gone off the deep end, spending $5000-6000 for a non adjustable Bilstein setup

I finally made the decision to join you and jump from the TCK SA setup I have to the FCM stage 3. Been talking with Shaikh for the past couple of weeks about my setup. I went with flat ride spring but the dampers just could manage the increased spring rates so here I am.

Where did you end up sourcing the H&R set? I’m trying to find best pricing right now, so I can order and have them drop shipped to FCM. Were lead times bad?

[Obioban]

I'm kind of excited for the extra clearance, as I was having to clean out track goobers getting stuck between my caliper and wheel between sessions:

[Obioban]

I'd like to hear your feedback on the 996/CSL brakes as I too want to FCP as much of my track consumables as possible! I'd really like to try out a set of 17x10 apex wheels on the 996 brakes to see if you can run continental take-off's or NT01's. I used to get 12-15 track days on NT01's on my E30 M3 which makes r-comps relatively affordable (compared to 3 days on RE71r's).

The 17x10 Apexs fit with space to spare over these. I kind of want to try the 17 x 9.5 et35s, as I don't actually like the et25 setup.

17x10 et25 brake clearance:

[S14]

Downgraded the brakes to 996 calipers with ZCP/CSL/Z4M rotors (so I can FCP my track rotors and pads). Not going to sell the brembos till I do a track event on these, but on the street they feel pretty indistinguishable from the Brembos. Which makes sense, since they're rigidly mounted brembo calipers with the correct bias/volumes for the chassis, but I still had some fears:

I'd like to hear your feedback on the 996/CSL brakes as I too want to FCP as much of my track consumables as possible! I'd really like to try out a set of 17x10 apex wheels on the 996 brakes to see if you can run continental take-off's or NT01's. I used to get 12-15 track days on NT01's on my E30 M3 which makes r-comps relatively affordable (compared to 3 days on RE71r's).

[Obioban]

Was the spring perch above your tire with your Ohlins setup?

Note entirely:

[Obioban]

Downgraded the brakes to 996 calipers with ZCP/CSL/Z4M rotors (so I can FCP my track rotors and pads). Not going to sell the brembos till I do a track event on these, but on the street they feel pretty indistinguishable from the Brembos. Which makes sense, since they're rigidly mounted brembo calipers with the correct bias/volumes for the chassis, but I still had some fears:



The front sway bar mount points tore off, so the car's off getting fixed for that (I don't weld well enough to be happy with my work on my car):



And the H&R coilovers arrived, that I'll be sending off to Fat Cats Motorsports for reworking. I go back and forth between being super excited and feeling like I've gone off the deep end, spending $5000-6000 for a non adjustable Bilstein setup

[r4dr]

Was the spring perch above your tire with your Ohlins setup?

[Obioban]

Turns out eibach makes a 6” long, 2.5” ID, 375 lb/in barrel spring, that they don’t offer except through GC... which will let me live my OCD to two decimal places.

(going with barrel springs up front because I want to have the spring perch above the tire, so I don't need as aggressive wheel offsets, but then need all the travel I can get (as that pretty much limits me to a 6-6.5" long spring).

[Obioban]

Wow. Definitely custom.

Are corner weights the real starting point for flat ride? I have fooled around with the spreadsheet, but I guess I need to see if FCM has posted a "how to use the spreadsheet" video.

Jesse

Corner weights are a good place to start, though probably not necessary if your car is close to stock. If you can get them, though, you'll be more accurate.

[D-O]

Wow. Definitely custom.

Are corner weights the real starting point for flat ride? I have fooled around with the spreadsheet, but I guess I need to see if FCM has posted a "how to use the spreadsheet" video.

Jesse