GMS - 2017 Alfa Romeo - 4C Coupe

It seems my saga with finding the seats and harness for solution for our 4C has reached the final chapter. If you are not interested in complete story, please skip the next paragraph below.

I had been using OEM seats for a few months, but didn't liked them since day 1 already. No need to explain, they just have an awful ergonomics. No one else drives my 4C and height and length clearance was always a bit of issue for me being 186cm, so I was always touching the roof when driving with helmet on, and I also couldn't fit the aftermarket harness bar behind the seat as it would take away too much of precious length clearance, causing me to sit too much forward with bent legs. I replaced OEM seats with Recaro Pole Position which I had from my previous project car and made a basic harness bar with 4-point harness that was in contrast to other aftermarket solution, positioned in the engine compartment and not behind the seat so I could push the seats all the way back.

The comfort with Recaro PP's was good and lateral grip too, given these are not full scale racing seats. I don't have much negative to say about these seats, as they truly are a very good all-arounder for weekend warriors. However they flex a lot under load and I never bothered to make proper seats mounts so they were squeaking under load and flexing even more and 4-point harness I had was mediocre too in terms of safety (chance of sub-marining) and I attached them very amateurish too. So, last year I finally decided to sort seats and harness like it should be. I was looking for lightest possible seats and decided to go with Eltech V3. The double skin seats look good (glossy on both sides), while single skin look not so good at the backside (raw carbon) but it doesn't really matter as the backside is not visible once installed in car. The comfort with the padding is acceptable and lateral support is somewhat sufficient, much better than OEM seats but of course, not exactly comparable with proper racing bucket seats. Weight is great at around 3.6kg for the single skin and a bit more for double skin version, which makes these seats a good upgrade for occasional trackers and weekend warriors looking for lightweight seat with basic comfort that can run 3, 4, or 6 point harness. Ergonomics seem best suited for medium built drivers while me being 186cm and 80kg, I felt a bit loose in the seat. The main downside for me was the helmet touching the seat headrest which seems a bit forward angled compared to common bucket seats, but it also seems my helmet is quite "long" at the rear. This bothered me a lot and was one of the main reasons I decided not to keep the seats. Regarding the build quality of the seats, you can expect somewhat standard Italian precision, nothing spectacular, but not all that bad either. While the seats are light, decently looking and well priced at around 1k€ each, there were small flaws that bothered me. Mounting holes were slightly misaligned, they forgot to make a slot for 6-point harness even though we ordered it specifically and the paintjob of clear coating had an orange peel, so we requested replacement and got them once we send the old ones back. Being in Slovenia, right next to Italy, that was not an issue to arrange in terms of logistics, but should we had to deal with that for a customer from USA it would be one hell of a logistics and costs. Either way, the next set of seats we got were better but still not perfect. The supplied Eltech brackets to fit OEM rails were not the most exciting thing either. They felt a bit under-engineered in terms of fitment precision and some heavily visible markings of the bending machine, some holes were undersized, requiring a re-bore and paint was not too impressive either, but they work so I guess I shouldn't be bothered. However, the sitting position with the supplied mounts was even higher than OEM, so that's why we went to design the seat brackets of our own. We also couldn't find a decent shipping rate for shipping the seats overseas, so we decided to skip the dealership offering for these and let potential customers buy directly from Eltech. If anyone would be interested let me know and I'll connect you with the Eltech. Overall the seats are not bad, but not exactly what I was looking for or required for my type of use (track focused) so I decided to look for another build. I can say I'm finally happy with the setup in all aspects - comfort, fitment, lateral support, weight, harness, looks.

It was a long road to get here with many wrong shortcuts I took just to learn that there are none when it comes to having the seats and harness done right. I ended with OMP Prototipo R seats, GMS SLR fixed seat mounts and GMS SLR carbon harness bar. Sitting position is as low as it can be. On lowest position the bottom of the seat is 10mm off the carbon tub. I also prefer slightly more backwards tilted seat to get more leg support in the thig leg area so with seats full slid back, the clearance between seat and rear firewall is only 10mm. Having harness bar behind, we would have lost at least 10 cm which was not acceptable in my case, so GMS SLR carbon harness bar was a must. I won't lie, the installation is demanding in terms of time and not most suitable for basic DIYers, but I don't see any other option to get so much height and length clearance as we have with this particular setup. The rigidity of setup is second to none as well. Seats or mounts don't flex even a bit and combined with 3" straps, 6-point harness it makes you feel like a fighter pilot ready to attack.

Here is the build...

Some bad ass cars we met yesterday on the track.

GT40 was my favorite.

Now, the MC20

The MC20 can't hide the weight and does feel heavy, but it packs a serious punch. The straight line speed is impressive. You can pass the 911 GT3's easily. We ran slightly more cambered setup on the front but otherwise pretty much stock car. Turn-in is very good and handling feels predictable. Seats are decent too. The fuel tank is small and you can only do maybe 10-15 laps before you run out of fuel. Engine doesn't sound as good as Giulia QV does and kicks similar as stock 4C does when shifting on WOT. Also on shifitng the engine doesn't sound as good. Interior is similar to the 4C but more refined. It still drones quite a bit inside though and there is lots of tire noise coming into the cabin.

I think this car can post some serious lap times when driven hard. In my case, it was customer's car so I couldn't afford to go all in, neither I knew the track all that well. But we had some fun nonetheless. But tracking a 250k€ with my budget wouldn't be much joy I'm afraid. You worry too much about crashing it, the running costs are high and depreciation factor is huge, so you don't drive relaxed. In my opinion, unless the money is absolutely not an issue you are OK to afford this car and enjoy it, if not I think it's more stress than joy. It feels like the car owns you and not the otherway around. I don't like that feeling. Perhaps it was just the kind of a trackday where mostly gentleman drivers came to, but there were some serious cars that just were not driven all that much. I mean, I understand that we are all different and some people just want to take it to the track for an experience, but I can feel their stress with cars passing you on the left and right and you're hopping for the PPF not to get hurt. I must say I prefer a slightly lower profile events better. People are more relaxed the cars are less of a concern and you always find someone to race against. So, once again it proves just how good of a car the 4C is. Running costs are a joke, handing is great and in the braking and cornering there won't be much of cars passing you. On the straight it's not all that important, is it? Power is like penis extension. Makes your ego grow but still hurts when a shitbox passes you in a corner. It was a great day anyway. We had a rain in the late sessions so there were only a few of us on the track remaining. Driving MC20 on semi's was plain terror...

The 4C in Brands Hatch did well. I preffered this track over Silverstone. BH is a medium speed track with big elevation changes and slightly banked corners vs. flat, very fast and mostly late apex corners in the Silverstone.

The level of grip on slicks and aero is impressive. What a bolide this car is. Fast, agile, but unforgivable. It's pretty much the same story with all cars, once you start improving grip, but even more so in the 4C as it has super wide track and short wheel base, so it is very hard to drive 10/10. Can't afford too much of a driver error, or the car bites you back. The grey area between limit and over the limit gets pretty narrow. It's either win or spin.

The car ran 2.0 Alfaworks engine, ported head, hybrid turbo, SC73 IC and GMS 3" exhaust (200 cell CAT + dual center out resonated muffler) and it worked very well. According to the owner, the car with our exhaust system is even slightly quieter than what it was with OEM race exhaust where it barely passed the noise limit of 100dB. Car did lack a bit of a fine tuning (alignment, damping, corner balance, ARB settings), but we established a solid base point setup from which the car should be fine tuned for each race accordingly.

Among the cars we tracked in the past days - MC20, A110S, I enjoyed the 4C the most. The MC20 is very, very fast on straights, but nothing special in other aspects. Alpine was pretty fun too, but way more oversteery on throttle than 4C. It almost feels more like a FR platform car than MR. I've noticed this already on the base A110 version when I was testing it previously. It seems that the suspension geo is designed in way, not to allow the car to squat much under acceleration, much less than 4C, so it also can't transmit the power to the ground all that good and you need to be patient more before accelerating out of the corners. And the engine induction noise gets a bit tiring on the inside. Sounds like artificially enhanced 4-pot banger with ITB's. I must admit that gearbox is slightly more responsive on downshifts than 4C's, can't deny that. It is a lovely car overall, and would be happy to further exploit its potential, but for us, the Giulia QV is the next project, while of course, the 4C will remain our main focus.

I'm re-setting the car for this season, based on some findings from past year.

Last year I ran around -3°00 of front camber and around -2°45' of rear camber. By the end of the season, according to the tire wear, the front end was close to perfect, just slightly overcambered as the outer edge had slightly less wear than inner edge. The rear seemed slightly undercambered, as there was still quite a lot of outer edge tire wear. So for this year, the setup is the following:

ALIGNMENT:
Caster: +4°35'
Front camber: -2°53'
Front toe: -0°05 (per wheel)
Rear camber: -3°15'
Rear toe: +0°16' (per wheel)

RIDE HEIGHT:
95mm front
105mm rear

SPRING RATE:
65N/mm front
90 N/mm rear

DAMPING:
Front R: -6
Front LC: -8
Front HC: -6
Rear R: -10
Rear LC: -8
Rear HC: -10

TIRES and TIRE PRESSURE
Front 215/45/17 @ 1.9 bar hot Federal FZ201 S
Rear 265/35/18 @ 2.1 bar hot Federal FZ201 S

AERO:
Front: Closed underbody
Rear: Rear wing AOA set at 12°

WEIGHT:
937kg (1/2 gas tank and ready to drive)

WEIGHT DISTRIBUTION:
40,4% front / 59,60% rear

CORNER BALANCE:
50% / 50% cross weight

This year I increased rear spring rate from 80N/mm to 90N/mm to compensate for added rear aero and deal with some of the outer camber wear we had issued last year. At same time the camber was increased, but damping was slightly softened.

It seems like a lot of rear camber, but we need to be aware that rear end is quite heavy, and if we compare the setup with the GT3 cup car which has similar weight distribution, it has pretty wild rear camber, so the setup we dialed in for the 4C, might be OK. Definitely an overkill for the road, but running slicks and soft semi's this should be good. We'll see...

GT3 CUP alignment sheet:

Engine and gearbox oil changed. Ready for the season!

Trackday aftermath. The mechanical handling is officially sorted out. Car feels surreal with the spring rates and geo matched to the latest aero spec. By far the fastest car on the track given the hp. Off to front aero now to match the rear end.

Once we get engine with another 100hp, the car will be awesome. Braking, cornering speeds are already next level to 911 GT3, Cayman GT4. However, we fall at least 5-6 car lengths behind on the main straights compared to other 400 - 500 hp cars.

Shots from latest track event.

Here is hybrid turbo with 1.6 bar of boost. First pull, that was aborted as torque was already at 500Nm which is a lot to ask from OEM cast conrods. Fueling wasn't optimized here either, so nevermind the spikey curve. We would are looking for something similar but with limited torque in low and midrange to play safe on conrods and clutch.

From 350hp onward the cost is pretty much the same whether you go for 400hp or 500hp and it requires:

Forged conrods
Forged pistons
Head porting
Engine assembly
Auxiliary fuel pump
Larger injectors
Custom turbo manifold
Custom exhaust
Turbo
Significant ECU mapping
Clutch upgrade

Finally under the 1.36 barrier, with new PB and lap time set at 1.35:945. There is still some time left in the setup and the driver, but we are happy with the progress and results of the upgrades on the car.

Stay tuned for more!

BTW: We are loosing roughly 2s for each 100km/h - 200 km/h, compared to 991 GT3RS, or other 500hp cars, so on this particular track, we are loosing about 5-7s / lap on straights, (there are two accelerations from 120 km/h - 240 km/h and one from 110 to 180 km/h), which means that braking distances and cornering speeds are pretty good with current setup and it's not optimal yet. It's very safe and predictable, but a tad too understeery. We are working on adding front aero and perhaps slightly stiffer rear spring rates with a bit more front camber. Anyway, 4C is a blast!