[52172]

Spool performance now has their hpfp available 1400.00.

[J.Rizo]

Glad I found this thread! Lots of good info. Thanks to everyone whos contributed info/specs.

I had plans for my previous F30 to be a double duty track car but it got totaled. I have an almost identical F30 now though so the plans are still going!

My biggest issue right now is trying to find functional downforce for the front to match the APR wing I have. Any chassis mounted splitters I find are expensive made to order pieces by aero companies or just DIYd. I like making stuff so not to bummed about potentially DIYing somehting. Anyways...

QUESTION: In all corners of the BMW world, Apex is the go-to. For good reason. However I wonder why I never see more F30 people opt for 513Ms? Compared to identically spec'd ARC-8s (18x9.5/10) they're only about a pound off and in the exact same price range.

My set has 265/285 RE-71Rs and they fit perfectly with no rolling, spacers, etc.

Is it bc people typically don't want that much rubber until higher power comes into play?

[romemedrano]

Originally Posted by J.Rizo

Glad I found this thread! Lots of good info. Thanks to everyone whos contributed info/specs.

I had plans for my previous F30 to be a double duty track car but it got totaled. I have an almost identical F30 now though so the plans are still going!

My biggest issue right now is trying to find functional downforce for the front to match the APR wing I have. Any chassis mounted splitters I find are expensive made to order pieces by aero companies or just DIYd. I like making stuff so not to bummed about potentially DIYing somehting. Anyways...

QUESTION: In all corners of the BMW world, Apex is the go-to. For good reason. However I wonder why I never see more F30 people opt for 513Ms? Compared to identically spec'd ARC-8s (18x9.5/10) they're only about a pound off and in the exact same price range.

My set has 265/285 RE-71Rs and they fit perfectly with no rolling, spacers, etc.

Is it bc people typically don't want that much rubber until higher power comes into play?

I built chassis mounted APR F80 splitter into my f30.

I used L aluminum brackets that feed off the subframe and square of at the back end that directly bolts onto the chassis. My plan is to make bracets for the front portion so its also as strong as the rear.

I see your in SoCal (I think), a few of us F30 guys going to Turn8 TrackDays on 2/28 you should sign up and get some seat time in! I posted info into the California Regional group if your interested! 4 sessions + open pit from 3-5pm for inter and adv drivers.

[J.Rizo]

Originally Posted by romemedrano

I built chassis mounted APR F80 splitter into my f30.

I used L aluminum brackets that feed off the subframe and square of at the back end that directly bolts onto the chassis. My plan is to make bracets for the front portion so its also as strong as the rear.

I see your in SoCal (I think), a few of us F30 guys going to Turn8 TrackDays on 2/28 you should sign up and get some seat time in! I posted info into the California Regional group if your interested! 4 sessions + open pit from 3-5pm for inter and adv drivers.

Thank you man! I think I'm gonna do something similar for the splitter situation.

I actually follow you on instagram, you're the only track F30 thats regularly active on instagram lol

I don't think I can make it to 2/28 but I'll definitely be out there soon. Cars more or less ready I'm just too busy rn.

[romemedrano]

Originally Posted by J.Rizo

Thank you man! I think I'm gonna do something similar for the splitter situation.

I actually follow you on instagram, you're the only track F30 thats regularly active on instagram lol

I don't think I can make it to 2/28 but I'll definitely be out there soon. Cars more or less ready I'm just too busy rn.

oh sweet man ! stock tracking has been fun as hell...I never realized how much potential cars really have if you leave it alone... I went balls to the walls on my other chassis track driving but now I realized what ive been missing out...RWD,RFT tires, Stock power = epic driver learning!

ill be tuned next months event and will be doing bimmerchallenge so should be fun to see what power can do to the chassis.

[Brady154]

I have Ohlins Road and track suspension, but I was really struggling for traction at COTA last weekend. What spring rates do y'all run? [IMG][/IMG]

[brigade24]

Originally Posted by Brady154

I have Ohlins Road and track suspension, but I was really struggling for traction at COTA last weekend. What spring rates do y'all run? [IMG][/IMG]

I am running 7kg/mm swifts up front and 20kg/mm swifts out back..I'm AWD and the car handles amazing in autox. If you're car is a lapping beast, you may need more upfront and less in the back than what i am running

[Brady154]

Originally Posted by brigade24

I am running 7kg/mm swifts up front and 20kg/mm swifts out back..I'm AWD and the car handles amazing in autox. If you're car is a lapping beast, you may need more upfront and less in the back than what i am running

I have 6 front and 16 rear, and I feel like I need 8 front and 12 rear. The rear end just wouldn't hook up. It feels like the rear is way too stiff to hook up. I also need a wing for some down force, so I'm not sure how much of my problem is lack of down force or spring rates.

[brigade24]

Originally Posted by Brady154

I have 6 front and 16 rear, and I feel like I need 8 front and 12 rear. The rear end just wouldn't hook up. It feels like the rear is way too stiff to hook up. I also need a wing for some down force, so I'm not sure how much of my problem is lack of down force or spring rates.

what sway bar are you running up front?

I would consider going to 8kg in the front and test. tightening up the front should stabilize the rear. I would advise against messing with the rears

when I stiffened up the front sway bar, it was very hard to get the car to step out. Im assuming your RWD so you would have 100% of the power going to the back. If you're not understeering, leave the rear setup as it is for now.

[FaRKle!]

Where/how are you losing traction? What tires are you running?

[Brady154]

Originally Posted by brigade24

what sway bar are you running up front?

I would consider going to 8kg in the front and test. tightening up the front should stabilize the rear. I would advise against messing with the rears

when I stiffened up the front sway bar, it was very hard to get the car to step out. Im assuming your RWD so you would have 100% of the power going to the back. If you're not understeering, leave the rear setup as it is for now.

Yes, it is RWD, and it is under steering. I can't carry much corner speed without the back end coming around. I'm running the Megan racing sway bars front and rear. The tires are Goodyear F1 Supercar 3, which is the 220 tread wear tire of choice. Messed around with tire pressures a good bit too, but no huge improvements.

[FaRKle!]

Originally Posted by Brady154

Yes, it is RWD, and it is under steering. I can't carry much corner speed without the back end coming around. I'm running the Megan racing sway bars front and rear. The tires are Goodyear F1 Supercar 3, which is the 220 tread wear tire of choice. Messed around with tire pressures a good bit too, but no huge improvements.

You said you're understeering AND oversteering (back end coming out). Which is happening where?

[Brady154]

Originally Posted by FaRKle!

You said you're understeering AND oversteering (back end coming out). Which is happening where?

My bad, I wrote that quickly. It does not under steer, only over steer.

[brigade24]

Originally Posted by Brady154

Yes, it is RWD, and it is under steering. I can't carry much corner speed without the back end coming around. I'm running the Megan racing sway bars front and rear. The tires are Goodyear F1 Supercar 3, which is the 220 tread wear tire of choice. Messed around with tire pressures a good bit too, but no huge improvements.

megan racing, 28mm front and 19mm rear, yes? that should be enough bar. Im at 25mm/19mm so you are certainly in the right ball park.

275/35 Goodyears on all corners corners?

I am wondering if you increase your front rates...would it resolve these issues??

[Brady154]

Originally Posted by brigade24

megan racing, 28mm front and 19mm rear, yes? that should be enough bar. Im at 25mm/19mm so you are certainly in the right ball park.

275/35 Goodyears on all corners corners?

I am wondering if you increase your front rates...would it resolve these issues??

Yes, the sway bars are 28 and 19, and the tires are 275/35 on all corners. I'm thinking that adding a wing and down force may require a stiffer spring anyway. Maybe I'll start with 8 k Springs up front and the wing and see what that does.

[FaRKle!]

Originally Posted by Brady154

My bad, I wrote that quickly. It does not under steer, only over steer.

Ah, got it. I would reduce your rear sway bar size to give the back more grip. I'm stepping down from a 17mm solid one to 15mm (from M240i) since my rear end is stepping out on the track.

Also, how stiff do you have the rear dampers set? If your damping is too stiff that'll cause grip issues too.

[Brady154]

Originally Posted by FaRKle!

Ah, got it. I would reduce your rear sway bar size to give the back more grip. I'm stepping down from a 17mm solid one to 15mm (from M240i) since my rear end is stepping out on the track.

Also, how stiff do you have the rear dampers set? If your damping is too stiff that'll cause grip issues too.

Interesting. I'll try softening the rear dampers next time on track and see how that does. Changing that sway bar is not an easy task. lol

[FaRKle!]

Originally Posted by Brady154

Interesting. I'll try softening the rear dampers next time on track and see how that does. Changing that sway bar is not an easy task. lol

Oh, I know! Haha. By the end of this weekend I'll have gone through three different rear AND front sway bars. I'm one of the few folks crazy enough to do those jobs a couple of times...

I have a 17mm RSB, and at my last track outing my rear end was coming out on trail braking (I had to be SUPER smooth to avoid that). When I disconnected the bar on day 2, rear grip increased significantly and allowed me to be faster. I'm stepping down to the F22 15mm bar. My rear spring rate is also 900lbs/in (same as the Ohlins).

The other option you have is to go to wider rubber in the rear. I really think a lot of these rear sway bars were meant to be used with close to OE spring rates, and not ones about 2x the OE rate like the Ohlins have. An LSD would help too.

[romemedrano]

Originally Posted by Brady154

I have Ohlins Road and track suspension, but I was really struggling for traction at COTA last weekend. What spring rates do y'all run? [IMG][/IMG]

Hey I saw you! I was gonna do SLB but man it was just a tad bit out of my budget at this time of year!

I'll be at GTA finals in buttonwillow and possibly in GTA road Atlanta! Hope to see you there.

[DVC]

Originally Posted by Brady154

I have 6 front and 16 rear, and I feel like I need 8 front and 12 rear. The rear end just wouldn't hook up. It feels like the rear is way too stiff to hook up. I also need a wing for some down force, so I'm not sure how much of my problem is lack of down force or spring rates.

I had the same issue with the 6k /16k setup as is came in the kit. After talking with the Ohlins rep, and Leonard from Swift springs, and running the numbers for optimal rates for my corner weights, they suggested going 8k front and leaving the rear at 16k. So I went with 7" 8k Swift springs for the front, and left the back as is..... it made all the difference in the world. The rear of the car is totally planted now.

By the way, I have H&R sway bars, with the front adjusted to the stiffer of the two settings (rear is fixed).

[johnung]

Originally Posted by DVC

I had the same issue with the 6k /16k setup as is came in the kit. After talking with the Ohlins rep, and Leonard from Swift springs, and running the numbers for optimal rates for my corner weights, they suggested going 8k front and leaving the rear at 16k. So I went with 7" 8k Swift springs for the front, and left the back as is..... it made all the difference in the world. The rear of the car is totally planted now.

By the way, I have H&R sway bars, with the front adjusted to the stiffer of the two settings (rear is fixed).

I've got the H&R sway bars on my 2015 335ix. They are awesome. Cornering is flat and balanced!

[EstorilMSport]

I'm running the aFe sway bars and KW Clubsport coilovers and the car is super planted.