It was this time two years ago that I first covered an Attack event at Tsukuba, and also the first time I saw the Friends Racing Nissan Silvia S15 in action.
I remember falling for the car instantly; its aggressive yet almost minimalistic approach was something that really stood out. A single GReddy logo on the hood was the only livery remnant of car’s previous life as a D1 Grand Prix drift contender.
The car has evolved greatly in the past 24 months though, so I just had to take a closer look at it while at Tsukuba Circuit on Saturday. Looking at the S15 in profile, you can see that it still sports one-off Friends parts, namely ground-hugging side skirts armed with a pair of bolt on canards, all body colored for extra effect.
With a 53-second lap time around Tsukuba’s 2.0km circuit under its belt, there’s no doubt the aerodynamic aids are doing their job, but by its very nature time attack encourages evolution, and this year the car showed up with a new front splitter and a pair of stacked canards, all left in bare carbon fiber. Above you can also see one of the large Endless Mono 6 front calipers and the massive grooved disc it bites down on.
The rear is now equipped with a triple-element Voltex wing, noticeably bigger than what was fitted before to balance out what’s now happening up front. The widened front and rear fenders remain, Swiss-cheesed to hell, as is the rear bumper to help eliminate as much drag as possible.
Air management is one of the most important aspects of a time attack car, and I always enjoy looking at how different shops approach different areas. The engine room can be quite a problem area for drag and overall turbulence; think about all the air that passes in through various intakes, air dams and via the wheel arches. The more effectively you can channel, direct and make use of it the better. So on top of two big vents to extract and divert air away, a large percentage of the hood surface is made up of louvers.
By looking at the engine bay you can see that these are there to vent hot air from under the hood while the center openings are there for the horizontally-positioned intercooler and the air guide underneath it which comes from the v-mounted radiator below.
Engine-wise, the VE-headed SR20DET has dumped the Trust T88 it was once running for a slightly smaller yet more responsive HKS GTIII-4R. This is comparable to HKS’s old TO4Z, but with the potential for around 700hp without any loss of low-down boost response.
During its time at Attack, the S15 posted a best lap of 55.573-seconds, which indicates that the team were out there to test and get a feel for the new setup and revised aero.
18×11-inch BBS RI-As feature at each corner, the wheels themselves weighing just 9.1kg (20.0lb) each without tires.
On the subject of tires, like many teams in Japanese time attack circles, Friends run Yokohama Advan A050 semi-slicks in G/S compound. As you can see, even brand new tires are shaved down so that the stickier underlying layer of rubber is available from the get go. This means the car only needs one warm up lap before an all-out attack.
The tiny split air dam is still there, but the round intake to feed the turbo has been closed up on this refined aero. From this angle you can also get a good look at the stacked canards.
One glance at the inside and it’s easy to see that this build started with a stripped-out shell. Surprisingly, the dash has been retained, but it’s primarily there to hide all the custom wiring for the MoTeC-based engine management system.
The passenger side of the cabin houses the oil tank for the dry sump system as well as a nitrous oxide bottle which feeds the single fogger positioned before the Plazmaman throttle body. This is a serious contender in every way, shape and form.
It will be interesting to see how much time the Friends Racing team can shave off their best Tsukuba lap with this new series of upgrades. One thing’s for sure though: we should all keep an eye on this S15.
Dino Dalle Carbonare
Instagram: speedhunters_dino
dino@speedhunters.com
if Shotaro Kaneda from Akira had a car, that S15 would be it fam
Now that you've mentioned it, that seems about right
I actually made a concept art of Kaneda's bike turned into a car myself, and the thing it's an S15 too. This S15 doesn't look way too far out
I feel like Im the only one that checks back every day to see the newest scoop (no pun intended) on the hottest cars you guys review, keep up the damn good work and i hope to be covered one day, I have a very interesting plan "hatching" for my chevy....
Thanks for the support man, we really appreciate it. And when you are done with that project, why no hit us up...
itll be a long time before i even start it, only 16 at the moment, but, this will be the most unique build you may ever see
Where are they jacking the car up from? The side runners, dif(?) and front A arms? Can someone let me know?
Rear diff and subframe it looks like, maybe the frame judging by the jackstands
Yes, common practice
Very interesting to look at TA car lap times around Tsukuba with all their horsepower, venturi tunnels, trick canards, etc. and compare them to the 44 second lap times of Formula Nippon cars and Super Formulas that seem very restricted in aerodynamics by comparison.
Makes me wonder why no one in the Time Attack community has focused on being lighter than other competitors as opposed the bulk of the series focusing on aero. Is there a minimum weight?
I think if you look at the new HKS BRZ car and Under Suzuki's S15, there is no more weight to shave really. Just the nature of tin tops , big wheels, big brakes etc.. cannot be compared to a open wheel race car.
I think that has occurred a bit, with the top level cars based on lighter chassis’s such as s15s and RX-7s now, as opposed to evos as they were in the past.
But on top of that, there is a critical point, where after you have a carbon body and no interior and all that, you can’t really pull much more weight out. I think the rules prohibit full on tube frames and those kind of really drastic measures too. I’m not sure though.
Thanks Sam. It peaked my interest when I was looking at the lap times. Tire compound is also important as I'm sure the F Nippon cars have superior rubber.
I'd be curious to hear an engineers explanation as to why they don't run reduced drag setups at Tsukuba. Aero doesn't do much (to my knowledge) until around 100mph. Even the fastest TA cars at Tsukuba are maintaining and average speed of about 85mph.
Depends on the rules, I recall when the Revolution RX7 couldn't participate in the WTAC as it has a tubular front and rear end. In Japan it's a but more open. But comparing formula cars on slicks against what are pretty much high end tuner cars makes no sense really. Even though they are what, 3 seconds away from each other now. But keep in mind HKS for some reason did the laptime with the 86 on slicks.
It doesn't, but that's how they choose to market it in Global Time Attack, often bragging about how the cars lap the same time or close to F3000 cars.
Thanks for the info about the 86 and its tires Dino!
+10 for the article title!
Thank you!
Does Friends Racing still have their Drag racing BNR 34? I remember seeing it in a few videos on youtube and it looks and sounds amazing, shame there isn't more coverage of that car on the internet
Good question. I'm not really sure.
That's what I meant <3
And yeah, I love the opening shot, it's similar to Ando's Evo from your post from few days ago, but I just love how contrasting the car is here next to desaturated February-mode track.
Thanks man!
Built and driven by Inose Tohru, the same guy who built the 'smoking', 1000hp NOS-equipped Toyota Aristo for D1SL.
When I mentioned smoking, yes... the car is seriously smoking.
Can anyone tell me what happened to Battle Evome? Did it just not attract enough teams and failed?
Pretty much, number of entrants fell and it made no more sense to do it this year. Too bad as I loved it so much, it was so small and tightly nit. Website is still there, who knows maybe they'll do a couple of sessions in 2019 http://www.be-circuit.com/tc2000.html
haven't heard about Friend's Racing for a while now, this is Tohru Inose's ex-D1GP car isn't it? Seems more tamed than the 1000hp he used to run hahaha. Also would be cool to feature Friend's Racing shop someday, they had quite a few good builds that are worth featuring here...
Yes and definitely Yes!!!