F80 Track Build

[SYT_Shadow]

Originally Posted by ninekrpm

those are good #'s SYT_Shadow and further validates the effectiveness of the GTMore aero...now I am even more excited as I transition from GT4 > GTMore

what moved me on the GTMore aero was a friend who runs at COTA - he has all the go-fast parts on his F80M3 and added 4.5-5 sec as he transitioned from NO aero to full GTMore aero. He validated this with a second driver who also drove his car pre and post aero and found similar lap time gains.

He said that he had to spend a full day on setup to rebalance the car a bit; but by end of day, they were a full 5 sec faster at COTA.

Not sure what I should expect...but I will say, I am exited, and looking forward to the test next weekend.

Everyone in SoCal runs massive aero; I know much of that is driven by the Time Attack culture; I found that the GT4 aero, which I thought was aggressive when I got it back in 2022...started to look small, call it "aero envy" LOL!

The aero difference is huge, all of a sudden the car isn't trying to fly off everywhere. Still, unlike power, the aero needs to be used to lower lap times.

Looking forward to having the m4 gt4 with gtmore aero, but we won't get an apples to apples, as there's a long list of goodies pending there.

[ninekrpm]

#GTMore

Excellent fitment

[ninekrpm]

The #GTMore wing!


Ohhh…just added 12” to the car, wil be a close fit in the trailer.

[b_w.]

Were you having problems overheating your diff prior to adding the cooler? Looking at the Drexler and trying to figure out if I need to add cooling. Chatting with bw they though they had not added diff cooling to a f8x yet and didn't have inventory of proper bango bolts to connect the drain line that wouldn't drop below the cooling fins. Thought that was strange because I thought they were running the csr diff on the gt more.Was looking at the m2csr Drexler but my cf ds isn't compatible so need to go with the diffsonline one.

Also Curious what ramp angles you went with?

[Track/S]

Originally Posted by b_w.

Were you having problems overheating your diff prior to adding the cooler? Looking at the Drexler and trying to figure out if I need to add cooling. Chatting with bw they though they had not added diff cooling to a f8x yet and didn't have inventory of proper bango bolts to connect the drain line that wouldn't drop below the cooling fins. Thought that was strange because I thought they were running the csr diff on the gt more.Was looking at the m2csr Drexler but my cf ds isn't compatible so need to go with the diffsonline one.

Also Curious what ramp angles you went with?

It is easier and cheaper to change the propshaft than to spend x5 more on a diffsonline diff.

[DRLane]

Originally Posted by ninekrpm

The #GTMore wing!


Ohhh…just added 12” to the car, wil be a close fit in the trailer.

How big is the trailer? Maybe I missed it in earlier post in the thread.

[ninekrpm]

Originally Posted by DRLane

How big is the trailer? Maybe I missed it in earlier post in the thread.

its a 22' enclosed trailer...it will fit, will just leave at least 18" less space for my crap

[ninekrpm]

Originally Posted by b_w.

Were you having problems overheating your diff prior to adding the cooler? Looking at the Drexler and trying to figure out if I need to add cooling. Chatting with bw they though they had not added diff cooling to a f8x yet and didn't have inventory of proper bango bolts to connect the drain line that wouldn't drop below the cooling fins. Thought that was strange because I thought they were running the csr diff on the gt more.Was looking at the m2csr Drexler but my cf ds isn't compatible so need to go with the diffsonline one.

Also Curious what ramp angles you went with?

I was not experience any heat issues...but wanted to take care of the investment as I found my self running several days in the heat of SoCal (95 deg temp).

Relatively speaking...it was a cheap investment and fun project.

When I bought it, only the default ramp options were available; however, I believe KMP can now make changes to final drive and clutches (tempting)

BW does not offer a kit...but it did take some searching to get all the banjo fittings put together.

[Track/S]

Originally Posted by ninekrpm

I was not experience any heat issues...but wanted to take care of the investment as I found my self running several days in the heat of SoCal (95 deg temp).

Relatively speaking...it was a cheap investment and fun project.

When I bought it, only the default ramp options were available; however, I believe KMP can now make changes to final drive and clutches (tempting)

BW does not offer a kit...but it did take some searching to get all the banjo fittings put together.

The new gear ratio offered by KMP is not valid, here you can see a person who has tried it and after doing a lap on track he sells it...
The OEM gear ratio in our F8X is perfect and does not need any changes.



https://www.kleinanzeigen.de/s-anzei...21780-223-6541

[ninekrpm]

Originally Posted by Track/S

The new gear ratio offered by KMP is not valid, here you can see a person who has tried it and after doing a lap on track he sells it...
The OEM gear ratio in our F8X is perfect and does not need any changes.



https://www.kleinanzeigen.de/s-anzei...21780-223-6541

Interesting this guy did a diff upgrade without upgrading the diff/lift kit or bushings...

factory is 3:46, I would not jump to a 3:91, but perhaps 3:71 would be better suited; especially in a 2nd great using a manual.

at the end of the day, I am pretty happy with my setup...

[Track/S]

Originally Posted by ninekrpm

Interesting this guy did a diff upgrade without upgrading the diff/lift kit or bushings...

factory is 3:46, I would not jump to a 3:91, but perhaps 3:71 would be better suited; especially in a 2nd great using a manual.

at the end of the day, I am pretty happy with my setup...

He's probably selling it with the OEM bracket so he doesn't have to buy another lift kit.

[SYT_Shadow]

Another weight loss idea? 18.7lb loss!

[DRLane]

Originally Posted by SYT_Shadow

https://www.instagram.com/p/DGEM4Fxtewk/?igsh=MWlkbjcya2dyMmE1eQ==

Another weight loss idea?

That’s beautiful!

[SYT_Shadow]

Originally Posted by DRLane

That’s beautiful!

this will go on the M4 GT4 and GTS1! 18.7lb!

[DRLane]

Originally Posted by SYT_Shadow

this will go on the M4 GT4 and GTS1! 18.7lb!

Not just weight, it’s levered weight hanging over the axle.

Does he have a like option for the front?

[SYT_Shadow]

Originally Posted by DRLane

Not just weight, it’s levered weight hanging over the axle.

Does he have a like option for the front?

yes, and for the radiator support. Those are already in

The OEM front bumper support is alu, while the radiator support is steel. So you don't lose as much as the rear bar.

[ninekrpm]

Originally Posted by SYT_Shadow

https://www.instagram.com/p/DGEM4Fxtewk/?igsh=MWlkbjcya2dyMmE1eQ==

Another weight loss idea? 18.7lb loss!

Ummm…I have already cut mine off.

The stubs remain on the fork with holes LOL

4# left…

[chetrickerman]

Do you have all of the Slon workshop products on your build?

[uncle ben]

That rear bumper support is a beauty.

[M3SQRD]

Originally Posted by SYT_Shadow

Another weight loss idea? 18.7lb loss!

This is another beautiful part from Slon!

One thing to note is a CF rear bumper carrier will absorb energy from a crash/impact differently from a steel or aluminum bumper carrier. The CF carrier won’t deform plastically like a metal carrier would as it absorbs the crash/impact energy; instead, it’ll brittlely fracture into multiple pieces except for the two main supports. If properly designed, the two main supports should axially crush as they absorb energy. Without knowing the design details, it’s impossible to determine whether the CF carrier would/wouldn’t absorb more energy than a steel or aluminum carrier.

An interesting example of how CF vs. metallic parts are designed differently to absorb energy in a crash is CF structure in the F22 fighter aircraft. It uses CF I-beam structures that use a sinusoidally varying web, instead of a straight web in a metallic I-beam web. This type of web is used to control how it initiates crushing during a crash and increases the amount of energy absorbed because a sinusoidally varying web is longer than a straight web so it can absorb more energy axially as it is crushed and it is also properly designed to initiate how the axially crushing of the web occurs.

[chetrickerman]

Originally Posted by M3SQRD

This is another beautiful part from Slon!

One thing to note is a CF rear bumper carrier will absorb energy from a crash/impact differently from a steel or aluminum bumper carrier. The CF carrier won’t deform plastically like a metal carrier would as it absorbs the crash/impact energy; instead, it’ll brittlely fracture into multiple pieces except for the two main supports. If properly designed, the two main supports should axially crush as they absorb energy. Without knowing the design details, it’s impossible to determine whether the CF carrier would/wouldn’t absorb more energy than a steel or aluminum carrier.

An interesting example of how CF vs. metallic parts are designed differently to absorb energy in a crash is CF structure in the F22 fighter aircraft. It uses CF I-beam structures that use a sinusoidally varying web, instead of a straight web in a metallic I-beam web. This type of web is used to control how it initiates crushing during a crash and increases the amount of energy absorbed because a sinusoidally varying web is longer than a straight web so it can absorb more energy axially as it is crushed and it is also properly designed to initiate how the axially crushing of the web occurs.

The front and rear bumper carriers are not meant to absorb much force in the event of a relatively serious collision. That job is meant for the actual frame and crumple zones. The crash bars are only meant to absorb a small amount of force for things like fender bender collisions. The auto manufacturers did this as a sort of sacrificial beam to avoid expensive frame damage repair during fender benders.

I went down a deep rabbit hole with my previous car when I was researching the legality of removing crash bars on street driven cars.

[M3SQRD]

Originally Posted by chetrickerman

The front and rear bumper carriers are not meant to absorb much force in the event of a relatively serious collision. That job is meant for the actual frame and crumple zones. The crash bars are only meant to absorb a small amount of force for things like fender bender collisions. The auto manufacturers did this as a sort of sacrificial beam to avoid expensive frame damage repair during fender benders.

I went down a deep rabbit hole with my previous car when I was researching the legality of removing crash bars on street driven cars.

That may be true but a metallic bumper carrier will absorb considerably more impact energy even in a “minor” accident due to large plastic deformation than a CF bumper carrier with brittle fracture. Given the weight of the metallic carrier, and the almost 19 lbm CF carrier, I suspect it’s designed to absorb a lot more energy than you think it does. You want to increase the time duration of an impact event to reduce the peak forces generated/transmitted during a crash (an impulse is the integral of force(t)*delta time). CF absorbs energy better if it’s under sustained crushing in axial compression (F1 cars use two replaceable CF tapered cones on each side of the monocoque chassis at the side pod inlets for lateral impacts). My grad school work was in the area of CF crashworthyness and energy absorption.