¶ Changes to the MCA Hammerhead Car
The MCA Hammerhead has always been a crowd favourite here at World Time Attack . It's gone through a couple of changes of ownership and it's here now as Tanuki . We're here with David from GT Auto Garage to talk a little bit about the car and , specifically , the changes that have been made . Welcome to High Performance Academy's Tundin Field Report podcast series .
In these special midweek episodes we look back through our archives to find the best conversations we've had through years worth of attending the best automotive events across the globe .
We've pulled the audio from these tech filled interviews with some of the industry's most well known figures and presented it in podcast format for you to enjoy as a quick hit of insider knowledge . David , for a start , the most obvious change here the engine . It was SR20 VE Turbo . It's not anymore . What made you go down the path of the VR38 ?
It all came about with . It's more of a reliability . You know the SR is lighter , it can make decent , really good horsepower . But we were wanting , as this year is , we wanted to dual drive , so the owner Wayne , have him in Pro-Am and then obviously Tim Slade Drive and Pro .
So that way , you know , with a VR 4.1 we can run 25 pounds all day basically with a .
You know it's unstressed so and that's the thing I think a lot of people would not really be aware of . You know these engines are making a thousand plus horsepower or give or take . They're thereabouts and you know we see these numbers thrown around like they don't really mean too much .
But getting that power reliably out of a two or 2.2 liter four cylinder engine , no matter what you're putting in it billet block or not it's hard work , right 100% .
Yeah , yeah , like , yeah , you can have everything under the sun , but you're on the edge of a four cylinder . It's a lot of boost and it's a lot of you know , everything's stressed .
So ultimately , the VR 38 will now 4.1 liter version of the VR 38 , you've just got more capacity . You're making that power with much less boost , much less stress on the engine . Yeah , we run 28 pounds max and yeah , and ultimately , what power are you producing now and how does that compare to where it was with the SR20 ?
I'm not too sure where they ended up with the SL . I think they were close to the 1100 . I'm not , I don't know , but we're at 1080 at 25 pounds .
I would assume then that there's a little bit more left up your sleeve if you needed it .
Yes , oh yeah , of course you always have to leave . You know you want the reliability where Jule entered the car , so we want to make sure that you know we can do the most over a long . It's a long weekend like , yeah , we're doing only one or two laps , but it's a long weekend still .
Yeah , absolutely . In terms of getting that power reliably out of the 4.1 VR 38 , I mean obviously at 4.1 liters is incorporating a stroker kit . What else is needed inside that engine to make that sort of power reliably ?
It's pretty . Actually the motor's pretty basic , in all honesty , in the scheme of what's available now . Like the motor was built six years ago now . So yeah , so the bottom end is pretty much other than crank rods , pistons , like it's got CNC heads on it , but the actual bottom end there's no billet mains . There's nothing special at the moment .
Hencewise it is a little bit dialed down , so we want to keep it reliable .
Obviously we see these engines and roll , race and drag applications making two and a half thousand horsepower , plus with billet blocks , but you're not there . Turbo sizing can you talk about what's fitted to it ?
Yeah , so there's just a GT 1000 kit from HKS . It's literally a factory streetcar bolt on kit and we went that route for because it's a very tight engine bay . It's really compact kit .
In terms of the difference in weight and weight balance front to rear versus the SR20, ? I would imagine you're taking a bit of a hit there with the VR 38? .
Yeah , like the balance . We lost about 4% on the nose , but what we make up in torque , that does the weight balance issue .
Yeah , another big change is the electronics package . Back in the MCA Hammerhead days it was running the Autronic ECU . You've switched to the MoTeC platform . Can you talk us through why you've gone that route ?
We as a GT Auto , we run predominantly on MoTeC systems and we've got the GPRO in this one Again with monster amount of torque , like from 3000 , it's a master , in all honesty , to control the amount of torque for Tim to drive it to his 100% .
Can you give us a high level overview of what that GPRO package allows in terms of torque management ?
It allows basically everything like you can from , like your second gear , low stuff . You can give it 500 newton meters at like two grand , or you can up it to a thousand newton meters , like wherever you need it . It also incorporates you know , there's a tie friction modeling within that as well .
There's a heap of like , I guess , drive rates and car rates to really support everything .
And we've got a couple of videos on that GPRO and the torque based model and the traction model . So if people want to dive into a bit more , we'll link to those as well . Do you want to take your car knowledge game to the next level ? Join us in the next free lesson at hpacademycom . Slash free and start developing your own skills today .
Other changes to the car . The ERO package looks a little bit different , particularly in the front end . Talk us through that .
It basically , to be brutally honest , it was to rebrand the car , like if we left what was on it , everyone would just you know , it's the same , it's the same .
So we had to reinvent the car , basically , and Andrew Brilliant , which I've worked with since when I was tuning an Emo back way back when it all broke the rules so , yeah , been working with Andrew since then we got him on board and to redesign the front end .
I mean the obvious one . There is the infinity wing , so the front end is a lot narrower than the hammerhead . Obviously it was named the hammerhead for a reason , I guess . The other element that comes in here you've got a car that's gone through a couple of changes of ownership . It was very , very well known and really successful as the MCA hammerhead .
Does that then create a bit of pressure on the team to sort of at least match or exceed its previous performance ? Yeah , 100% .
Well , I guess when we first took ownership in January this year , we as a crew briefing we wanted to beat the original lap record of the car and yesterday we went half a second faster . So we're stoked yeah 100% stoked .
What is that lap time that you're done to ? At the moment , 120.45 . This is a 19 in it today , maybe .
The way the conditions are today , we're pretty , pretty happy . We're thinking we're close .
In terms of that , we're here . It's early morning on the Saturday , which is the big day at world time attack . It's pretty cool this morning . Obviously , as the day goes on , the temperature increases . From a running perspective , what's the ideal conditions ? Do you want that cooler temperature for the engine ?
How does it affect the grip as the track heats up With the temperatures .
Obviously we've got a full brand new PWR cooling package in it . The temps in the car don't really fluctuate during the day . Yeah , there's a five six degree change depending on midday temps . But again , yeah , grip levels obviously will suffer , especially towards the end of the lap , but so far , again , we haven't really found the limit of that yet .
New build , so first year out and yeah , I suppose that is actually something that's probably worth mentioning here is that the car hasn't had a lot of testing up to this point , so sort of world time attack has almost become a shakedown .
Yeah , well , we've literally done . What are we now 40 laps up in Queensland Like we have done some testing , but not here . Like you know , sydney Motorsport parks are different animal . You know , queensland Raceway is pretty basic , so , yeah , so this is literally its first major shakedown .
One big change to the rules for this year , in 2023 , is the move away from the dot control tyre to a full slick . What's the learning curve been like with that ?
I mean , I know , talking to drivers and teams , in the past , the dot control tyre was really good for three quarters of a lap and then it was sort of overheating and really start to go away dramatically . It was only good for that one lap at best On a full slick . Obviously you've got the ability to do more
¶ The Process of Tire Temperature Control
laps back to back . So is there a process more about getting the tyre up to optimal operating temperature ?
So previously , as I understand it I mean , I haven't driven here on those tyres , but the driver would have to sort of creep around the out lap , basically not putting too much energy into the tyre so it didn't overheat , and then sort of coming out of the last turn onto the front straight .
It was like all on and then you know , try and nurse it through a full lap . So with a slick , is there a different process to that ? Well , yeah , we run tyre ones , so okay , so it's always up to temperature as you're rolling up that lane , correct , yeah ?
so then the drive only has to worry about your brake temps and yeah , yeah , still getting obviously temps into your rims et cetera . But yeah , like tyre warmers obviously help a lot .
Alright , look . Thanks for the insight into the car , david . It is a crowd favourite , it's one of our favourites , and we hope you can go a little bit faster at sub 120 today . Best of luck , thank you very much . If you enjoyed this podcast , please feel free to leave a review on whatever platform you've chosen to listen to it on .
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