27

Attacking Time with the LYFE Motorsports Nissan R35 GT-R

by Mike Kojima, action Photos by Andrew Perry, GTA and Snap Studios

When Cole Powelson set out to build an R35 GT-R he initially didn't have the ambitious plans to build one of the world's fastest time attack cars. The 2012 GT-R originally was built as a modified but streetable time attack car which was run for fun.  Then the car was repurposed and underwent a metamorphosis, eventually being rebuilt into the sophisticated machine that appears on our site here.

The car's debut after the extensive retrofit was at last year;s World Time Attack and like our own effort, it wound up being anticlimactic with the car suffering an engine failure right out of the block.  

Then Motovicity Distribution announced the Speedring Challenge several months ago. Motovicity worked with Global Time Attack to sponsor a time attack at Cal Speedway with a twist. Motovicity, the North American Distributor of HKS would bring the HKS Time Attack R35 GT-R from Japan for the event. 

Not only would Motovicity bring the HKS GT-R, they also announced that the legendary Nob Taniguchi would be driving it.  To sweeten the pot to the point of it being irresistible, Motovicity put up a bounty of $25,000 on the HKS GT-R's head for any team that could beat it.

The combination of some stiff competition and some real money on the table was a lure that had the LYFE Motorsports crew in travel mode, shipping their GT-R out to the West Coast.  At Cal Speedway, we were  able to catch up with the team and get a good close look at the car and its insides. We had enough time to thoroughly go over the car and the crew were generous enough to share many of their speed secrets with us that we could put together this great feature.  So check it out, we hope you enjoy!

 
The VR38DETT engine was extensively modified, being stroked to 4 liters with a Greddy crank featuring a 92.4mm stroke. The engine uses Carillo rods and CP forged pistons. The engine runs Kelford cams and valvetrain and is kept lubricated with the assistance of a Magnus dry sump system.
The engine uses custom charge piping fabricated by LYFE Motorsports vented by lightweight and compact Turbosmart Race Port blow off valves. A stock intake manifold is used with AMS fuel rails feeding 2000cc Siemens injectors. 

The stock but highly effective coil on plug direct fire ignition system has been retained to fire HKS Iridium spark plugs.

 
AMS cast exhaust manifolds feed efficient and fast spooling twin Garrett GTX3076 ball bearing turbos.  AMS 3" stainless downpipes feed the custom LYFE fabricated side exit exhaust system.  

Twin lightweight and compact 50mm Turbosmart external Pro Gate wastegates help keep the boost pressure under control. All of this hot stuff including engine compartment air is vented via a hole in the car's flat bottom that terminates into a central "Freedom Tunnel" that exists in the rear of the car.  All told this engine setup produces a massive 1160 whp!

 

This internal bay holds the Fuel Safe Fuel cell, the car's electronics suite and the engine's dry sump tank.  This offsets the driver's mass and helps keep the car's mass centralized between the wheels. 
Page 1 of 11 Next Page
Bookmark and Share
Comments
gstmike
gstmikelink
Monday, September 26, 2016 11:51 AM
A truly awesome car and team!
Mike Kojima
Mike Kojimalink
Monday, September 26, 2016 2:44 PM
Mike, you helped as a consultant right?
gstmike
gstmikelink
Monday, September 26, 2016 2:50 PM
No sir I have no claim to anything on that car other than enjoying watching it run and finding everyone involved in their program thoroughly enjoyable to be around at the track.
SM_Clay72
SM_Clay72link
Monday, September 26, 2016 6:54 PM
This makes it sound like the ARK car is just a very expensive failed sculpture now? The amount of hours in that thing though...

I sure hope that rear wing produces over 100 lbs of down force! Must have been a typo for 1000. Thanks for the look at this car. Impressive stuff. $^3!

Mike Kojima
Mike Kojimalink
Monday, September 26, 2016 7:11 PM
Fixed the typo, thank you for spotting it! We are working on the ARK car bit by bit. The hard thing is the steering system and getting the flex out of it as well as redoing all of the electronics. A lot of the flex is due to the whole unibody moving after we make the rest of it strong enough.
ginsu
ginsulink
Monday, September 26, 2016 9:03 PM
The three zone front diffuser makes sense considering the velocity of the air behind them. Obviously the inner zone feeding the wheel well is going to have the highest pressure and thus the velocity of the air is slower. So the diffuser angle is greater to slow the air through it. The outer diffuser obviously needs less angle because the air coming round the side of car is moving at high velocity.

The side gills behind the fender are to straighten the turbulent flow coming off the tire, which should lower drag by creating a half nozzle to speed the air up.

All these air guides were originally developed in F1 to gain precious aerodynamic efficiency after rule changes forced them to.
tyndago
tyndagolink
Monday, September 26, 2016 9:15 PM
Trailing brake caliper now, too.
Mike Kojima
Mike Kojimalink
Tuesday, September 27, 2016 10:37 AM
I still think the main reason for the different front diffuser heights is the amount of length available for them, the angles cannot exceed 10 degrees or so to avoid flow separation so the end ones have to be short due to the amount of room available to them so of course the tops are lower.
cheechthechi
cheechthechilink
Tuesday, September 27, 2016 10:02 PM
I believe Ginsu has a pretty good explanation for the varying lengths on the front diffusers. Diffusers are pressure recovery devices. As you travel along the length of a diffuser, its area expands: slowing down the flow velocity and increasing pressure in the flow.

You'll often see diffusers used in areas where a section of high velocity, low pressure flow terminates to a region of low velocity, high pressure. Relative to the static pressure at the rear of the car, the flow traveling under a flatbottom has much lower pressure. The same is true of the static pressure in front of a rotating wheel in contact with the ground and flow underneath a splitter. Without a diffuser, the high static pressure in front of a rotating wheel and behind a car would impede the flow coming through a flatbottom or splitter, ultimately lowering the total flow velocity, increasing pressure under the flatbottom/splitter, and thus reducing overall downforce achievable. The goal of the diffuser is to gently increase the pressure in the flow stream to that of the static pressure in the region where it exits.

Diffusers also have the interesting attribute that right at the diffuser entrance, the static pressure drastically drops to a level lower than that at the throat, due to the sudden area expantion (this explanation I'm somewhat shaky on).

Also, the 7-10 degree diffuser angle rule is a myth that comes from the design of ducting, which does not account for the 3-D flow in an automotive diffuser. Diffuser angles much higher than 10 degrees can be achived by utilizing vortices, which help keep flow attached to the roof of a diffuser. Willem Toet has a great article of this on Linkedin.
Mike Kojima
Mike Kojimalink
Tuesday, September 27, 2016 10:15 PM
The 7-10 degree rule is not a myth but a good safe rule of thumb for grassroots builders who don't have access to analytical tools and budget for a lot of test time. Sure you can exceed it with vortex generators and strakes but for amateurs, the configuration and placement of these is a guess and often counter-intuitive.
cheechthechi
cheechthechilink
Tuesday, September 27, 2016 11:05 PM
Please don't misunderstand me I don't mean to come off as condescending, but rather add to the discussion. The grassroots builder doesn't have access to analytical tools sure, but they do have access to experimental tools. You can watch flow separation using a variety of techniques, one being low buck yarn tufts and generic go pros. That will give you a qualitative assessment of if your flow is separating or not. The same can be done with thinned motor oil spread on the surface. For a quantitative method you can use industrial differential pressure gauges to measure static pressure.

Just because the grassroots builder doesn't have a cess to fancy tools doesn't mean that they can't use engineering approaches to develop a cars aero. Ultimately I'd hope that the grassroots folks treat aero development as an experimental excercise, because generalizations with aero get you into trouble fast. Also Jim hall developed the first chaparral car using nanometers so there is definitely power in the basic experimental methods, they just tend to be more tedious than the fancy stuff.

Again not trying to talk condescendingly, but rather expand the grassroots knowledge.
cheechthechi
cheechthechilink
Tuesday, September 27, 2016 11:06 PM
*manometers
Mike Kojima
Mike Kojimalink
Tuesday, September 27, 2016 11:25 PM
Mark Donahue did a lot of aero development on the Penske 917-30 with tufts and oil drop studies. Oh yeah but grassroots guys usually can't afford much more test time than the morning warm up, heck that's me on my personal car.
cheechthechi
cheechthechilink
Tuesday, September 27, 2016 11:35 PM
With all due respect that is a poor excuse. Yarn tufts cost less than 3 dollars. Setup can be done the day before a track day. At least in a typical time attack day you get at least 5 runs. More than enough time to try stuff.

Also I see grassroots guys from track day to track day spend lots of money and time changing aero setups to "copy the pro cars" without focusing on the most important fundamental thing: the test method.

You wouldn't develop a suspension without measuring tire pressures/ temos, getting subjective driver assessments. You wouldn't tune a car without checking your ecu parameters. So why would you build/develop aero without understanding the flow field?
Mike Kojima
Mike Kojimalink
Wednesday, September 28, 2016 12:04 AM
With me, the most time I have is to tune the aero balance by messing with the rear wing. With customers, generally teams that can afford to pay me can afford test time but much of that time is spent sorting out the motor tuning, electronics integration, suspension set up and some is spent playing around with the aero but a lot of that is playing with the rear wing and cut and try then review data. I haven't worked with anyone with the budget to have fabbies waiting to build a new diffuser trackside so I could see if a 15 degrees diffuser might not separate if I tune it with strakes then tuft test it, then redo it. So far we are lucky to have a rough CFD analysis done of the car and tune from there. Real world there usually isn't time and money to do extensive aero tinkering, if you are lucky there is enough budget to take care of the Pareto vital few to get a reliable consistent car on the track. I would like some day to work with a team that has the budget to do everything right!
Mike Kojima
Mike Kojimalink
Wednesday, September 28, 2016 12:07 AM
The other thing is that 99% of grassroots drivers can benefit more from seat time than any amount of tinkering! So to me that means more time making the car lap after lap reliable and fuss-free. So my advice is something like this, don't skimp on plumbing and wiring, have the ability to overcool all fluids, keep your car simple, build for bulletproofness, prep your car for the next event when you get back from the track and not obsess about extracting every last bit of power and grip with a lot of things and this means not getting carried away with aero because it is not something you can common sense. Execute the basics well and you might win championships, heck, this goes for pro racing even!
cheechthechi
cheechthechilink
Wednesday, September 28, 2016 12:21 AM
I guess we'll just have to agree to disagree. The time attack team I work with started with an aero test budget of $0. I've even spent my own money to buy test equipment and I've never been paid for my work, so I certainly understand the challenges that the grassroots racer faces.

But ultimately racing is about development: both car and driver. So the teams that find a way to take their aero development just as seriously as their suspension and engine development have a lot to gain. And it doesn't have to be expensive.

But ultimately to each his/her own.
Mike Kojima
Mike Kojimalink
Wednesday, September 28, 2016 12:36 AM
I totally agree with you. Actually where we disagree is that I believe that a low budget team needs to focus money and manpower on basics like reliability before extensive aero development. Sort of like the Spoon USA Team I work with, a very simple and reliable car with simple aero that we tuned with limited time, cardboard, tape, and common sense, sticking to safe fundamental aero rules. The car happens to currently hold the unlimited FWD record beating a million dollar technological terror. My contributions to the aero which made the car about .8-1.2 seconds a lap faster, reduce the diffuser angle, trim out the wing, use tape and cardboard to increase stagnation pressure in the front and seal the splitter to the airdam. A one session test program using safe tricks. That's low hanging fruit. Now the trick is to find the money to do those tricks in a way that is more durable and more cosmetically acceptable. The rest of the budget is being used to improve driver safety and drivetrain reliability. If more can be found it will be to improve thermal control without affecting aero. In this case time and money has to go to bigger fish to fry than tweaking and experimenting with aero past the basics that may or may not work.
cheechthechi
cheechthechilink
Wednesday, September 28, 2016 12:44 AM
Also mike there is actually a free cfd program out there. It is called openfoam. It is very powerful and is even used by manor f1. But it's also a pain to use. But with everything, tradeoffs.

I do also respect the work done on the spoon civic. I enjoyed seeing it break the record at slb.
Mike Kojima
Mike Kojimalink
Wednesday, September 28, 2016 12:50 AM
What do you think of the somewhat crude approximations of aero parts that CFD suggests that most of us end up building? Like roughly shaped sheet metal instead of the nice bits CFD told you to make? How much is lost transferring the design to the materials most of us can afford to work with? Also, I feel that CFD isn't the total solution, it's a rough approximation that is better than you eyeballing it. Total CFD design cars have been failures. Physical models are way beyond what any of us can hope to do. What do you think of non-moving ground plane full-scale wind tunnels?
Mike Kojima
Mike Kojimalink
Wednesday, September 28, 2016 12:59 AM
Good tip on openfoam too!
cheechthechi
cheechthechilink
Wednesday, September 28, 2016 2:16 AM
I wholeheartedly agree with your statement that CFD is not an absolute solution and is flawed in many ways. To use a tool you have to know how it works and its limits, without such knowledge its use is dangerous. To answer your questions (based on my limited knowledge. I am not a professional by any means) :
CFD is inherently sensitive to geometry. But sometimes what is more important than getting the absolute accurate/most precise answer is having a way to evaluate changes relative to simplified geometry that you have a good understanding of the flow field. This helps at least push you in a closer to right direction.
Hands down for automotive work a rolling road windtunnel is far superior to static floor windtunnel, especially if you are studying ground effect. However, a lot can be still learned from a static floor windtunnel, you just have to realize that you are not seeing the full picture.

On the topic of Windtunnels , CFD, and Track Testing (based on what I know currently):

The reality is that the most accurate way to get the most real world data on the aero performance on a car is physically measure the pressure and velocity distributions on a car as it goes around a defined course. But, nothing is ever simple with aero, and one quickly finds that getting repeatable data where one can find trends and evaluate changes is very hard to do in the real world environment. This creates the need for a controlled environment where trends and changes can be evaluated much easier. Enter the Windtunnel.

The windtunnel is nice because you are still testing a car/model in the actual medium of air, and are taking physical measurements. While the windtunnel cannot easily simulate all the random effects of the real world, it gives a nice representation of what can happen. It also makes it easier to spot trends and relative changes (my limited experience with aero suggest that sometimes evaluating relative changes rather that seeking absolute accuracy is more beneficial). The problem with windtunnels is that it is hard to simulate all the random effects of the real world, models are expensive to make, and testing changes become super expensive. This gives the need for a controlled test method where many changes can be rapidly and quickly explored at lower cost. Enter CFD.

CFD aims to simulate the controlled environment of a windtunnel through mathematics. CFD software at its heart is just a solver that is solving the Navier Stokes partial differential equations. CFD is powerful because you can run through many different types of geometry changes/flow scenarios and relative to windtunnels quickly evaluate changes and trends. However, because CFD is at its heart a mathematical description of the flow field it suffers from its own problems namely: 1. The assumptions made in generating the Navier Stokes Equations 2. The ability to actually solve the N-S equations. Without getting too much into theory, CFD is a numerical method, meaning that it can't directly solve the equations for the flow field (Navier-Stokes eqns) for all points in time and space. Rather it takes a defined fluid volume, breaks it up into sections (descretization aka meshing), and then based on information provided by the user at the boundaries (boundary conditions) estimates the answer to the N-S equations at those boundaries , then marches to the next fluid element and estimates the answer for that fluid element , etc., etc. until the entire fluid volume is covered. This makes your CFD answer highly dependent on the accuracy of your model geometry, mesh size and type, and boundary conditions. You could enter in crap boundary conditions, have a crap mesh, and get… a crap answer. The skill in using CFD is knowing how to differentiate crap from not crap. 3. Turbulent flow. F’n Turbulent flow. Turbulence is inherently random by nature, so statistical models are used to mathematically attempt to describe it. Most CFD solvers use a method called RANS (Reynold’s Averaged Navier Stokes) to account for Turbulent flow. It is the least accurate method but the most practical (others currently being researched are LES- Large Eddy Simulation, and DNS – Direct Numerical Simulation) Turbulent flow causes a lot of error in the CFD description of the flow field (Also why I think Nick Wirth’s all CFD approach failed on the Virgin F1 car, but had success with the Acura LMP cars). 4. Computational hardware. Less of a problem nowadays, but the more accurate and detailed you want your CFD simulation to be, the more taxing it is on the computer. Most people don’t have the resources to use supercomputing facilities so there is a physical limit to how detailed of a model/simulation you can make.
Ultimately I believe top pro teams use all three methods. CFD is first used to test out many concepts and ideas and “hone in” on a solution. Once a few good solutions are found they move to the windtunnel to test. From here they will test and come up with a concept that is used on the actual race car. Test data from the actual car then ultimately lets the team know if they succeeded or not. You’ll often hear of teams struggling with correlation somewhere between the trackside testing, windtunnel testing, and CFD (Ferrari comes to mind, recently).
When you’re a grassroots racer you have to realize that your development methods won’t nearly be as good as the pro teams, but you still can accomplish a lot by trying to understand how the flow field around your car is like. Most racers/teams at the grassroots level will probably be limited to track testing. That’s fine, its more tedious but if you take a methodical approach you will learn so much. The more engineering/science inclined can take it a step further with CFD. This will greatly increase your development productivity, so as long as you are aware of the pitfalls of CFD. With most of these things you do the best with what you can, and you find ways to be competitive on your limited resources. I always tell the guys on our team, if Andrew Brilliant’s aero work is like carving with a fine knife, then we’re just taking a machete to it. But its still better than not trying at all.
Mike Kojima
Mike Kojimalink
Wednesday, September 28, 2016 11:40 AM
That's my understanding of CFD results as well, it is useful for quick comparisons in developing surface geometry but not the end all and sometimes the track and tunnel data don't correlate.
warmmilk
warmmilklink
Wednesday, September 28, 2016 12:50 PM
Let's go spend a $100k+ and build this time attack GTR for a chance to win $25k?? Alright!

Haha, I love the logic! I guess everyone needs to justify their build somehow...
Mike Kojima
Mike Kojimalink
Wednesday, September 28, 2016 2:12 PM
What is wrong with that?
warmmilk
warmmilklink
Wednesday, September 28, 2016 8:41 PM
only thing wrong with that is that I don't have a $100k+ to blow on a GTR build... haha
Mike Kojima
Mike Kojimalink
Wednesday, September 28, 2016 8:54 PM
cheechthechi, is aerodynamicists your primary job for your team?
cheechthechi
cheechthechilink
Wednesday, September 28, 2016 9:19 PM
The time attack stuff is just something I do for fun/ to build my aero knowledge. However yes, on the team that I work with I do all the aero development and a lot of the data stuff as well. Still have a lot to learn, but I enjoy it a lot.

Mike Kojima
Mike Kojimalink
Wednesday, September 28, 2016 9:24 PM
No wonder you have time!
cheechthechi
cheechthechilink
Wednesday, September 28, 2016 9:34 PM
Haha, yes it does help to have specialists on your team. But even our team is a small operation, and as you well know you can never have enough help.

Also I think another thing that the grassroots teams need to understand is that there are a lot of young engineers like myself that are looking to break into professional motorsports and are willing to help develop a car for a team to build experience. However, you have to market your team in a way that makes it worthwhile to attract that talent. I actually approached the team that I work with now to help them with their aero. 90% of the reason I chose that team was because they were the only one at the time with a website. So I guess marketing is also important for the grassroots guys..not just to get sponsors but also to attract crew members as well.
Mike Kojima
Mike Kojimalink
Wednesday, September 28, 2016 10:23 PM
Do you work for Professional Awesome?
cheechthechi
cheechthechilink
Thursday, September 29, 2016 5:06 AM
Jager racing
Mike Kojima
Mike Kojimalink
Thursday, September 29, 2016 11:54 AM
Oh cool! We need to feature that car as well.
ginsu
ginsulink
Friday, September 30, 2016 1:14 AM
CFD sounds a lot like FEA in the garbage in/garbage out sense. I was happy in FSAE when I started seeing realistic results from the solver for a sway bar simulation. Again it just seemed to confirm what we already knew.

I've gained much knowledge from aero just by following F1 and analysis of design changes. ScarbsF1 was an invaluable resource as well as MulsanneCorner. There is something about good aero that makes sense to me. I think I can see the flow 3D a lot better than most engineers. The way leaves on trees can collapse into a lower drag form and then spring back to collect light.

The active aerodynamic surfaces is what I really want to develop. I really look forward to seeing full body DRS in the future. Downforce and low drag constantly changing depending on speed and acceleration. I know it's probably more of a problem with current materials. I know BMW has a design for faired front wheels covered by some piezo electromechanical skin (yet to be developed). As always, humans imagine something unable to be built.

Although I look forward to analyzing the Aston Martin/Red Bull collaboration with the great Arian Newey, who has yet to design a road car. From what I know it will have the downforce of an LMP1 car. Which, I imagine, is over 1500lbs.
ginsu
ginsulink
Friday, September 30, 2016 1:25 AM
Actually, when I think about it, you need 3 different aerodynamic configurations for a race car. Low drag for positive acceleration, high drag for negative acceleration, and max negative L/D ratio for cornering acceleration.
Mike Kojima
Mike Kojimalink
Friday, September 30, 2016 1:59 AM
Whenever I have a long talk with Andrew Brilliant I realize how some of my assumptions are wrong and how much I don't know about aero. This is one of the reasons why I always preach to grassroots folks to use caution and stick with basics when applying aero to their cars. Sure a lot of us think we have an eye for flow but flow is a very complex thing that is beyond most to see.
ginsu
ginsulink
Friday, September 30, 2016 11:05 PM
Its surprising how much can be accomplished with intuition and passion. It doesn't necessarily make you right but it can keep you focused on the outcome. When racing becomes only science you drain the life and fun out of it.

For me, I love racing and modify the vehicle to improve handling. But I don't have the budget to develop even a fraction of the ideas my mind generates, but I have the desire to push development regardless. So I look for ways to shave grams or redistribute weight. Aero development is strictly limited to well known principles. But, regardless of what I can build, my mind imagines something much better.

Last night, I got the idea in my head of building a tire with a heating element embedded into the carcass. Just imagine having your tire temperature computer controlled, always at the right temp for max grip.
Mike Kojima
Mike Kojimalink
Tuesday, October 04, 2016 1:30 PM
tire cooling might be better
ginsu
ginsulink
Wednesday, October 05, 2016 10:14 PM
Was thinking for AutoX, never been able to maintain consistent temps. But why not F1? Tire blankets seem a bit 20th century.

Would be nice to maintain a specific tire temp regardless of conditions. Would also be nice to dynamically change tire pressure. Lower pressure during rain, higher in dry, maybe even increasing pressure depending on cornering or staightline acceleration.

Our FSAE team once won accel tests with 10psi in the tires. They couldn't get them up to temp otherwise. Of course the car sucked on the AutoX course with those tire pressures.
Mike Kojima
Mike Kojimalink
Thursday, October 06, 2016 12:21 AM
Just about all motorsports struggle with tires overheating, not the other way around.
Post Comment Login or register to post a comment.

MotoIQ Proudly Presents Our Partners:



© 2018 MotoIQ.com