Mungy's R31 Time Attack Build

[mungy]

well reading those track times and the cars that have done them kinda makes me sad

mayb i should aim for something more like 1:20?

Braking and suspention hasnt been fully worked out yet but s13 gear up front and custom work in the rear is all we've decided so far

[Damo_R34]

Yeah i think 1:25 in a 31 is a pretty respectable time.

[Bl4cK32]

my 2c is throw the time book out the window. Do what you can to the car, and see what you can improve on. Otherwise everyone will keep shooting you down telling you what you cant do, rather than help....like a lot of replies so far.

Good luck, and hope it goes well.

[Snowman]

my 2c is throw the time book out the window.

Absolutely. The project is a cool one however and I'm looking forwards to seeing how it goes. I have a buddy looking at grafting an MX5 IRS into a S3 RX7 to build as a Targa Classics car. People say he is mad but like you he is looking to build a quick car on a budget.

Anyways - keep at it.

[mungy]

Hey guys the from braking system has been chosen! And would like some advise or things to change

So it will have modded s14 knuckles with stagea hubs, s13 Adj LCA's and stage 1 R33 GTR brakes with braided lines

That'll give me stopping power in the front! Now I gotta figure out how to balance the rear with the front any suggestions?

[Roy]

I personally would just go with R33 GTS25t brakes rather then the far more expensive R33 GTR brakes. You will be able to get rotors and 4 pot fronts and 2 pot rears close to fitted for the price of the GTR fronts alone. And the major difference in a car with your grip and weight will be in the pad, not in the need for large rotors

[Daleo]

XF Falcon Rear ventilated discs & calipers are a near bolt on fit on the Borg Warner diff; 296mm x 30mm rotor, I think.

Very minor machine work from memory. Retains intrernal handbrake too! Other than that, use the R33 2 piston jobbies with matching rotors and make some new backing plates.

It would pay you to have a look at the R31Skyline website too.

Good luck champ!

[Sir Lord Van Von Vader'ham]

I personally would just go with R33 GTS25t brakes rather then the far more expensive R33 GTR brakes. You will be able to get rotors and 4 pot fronts and 2 pot rears close to fitted for the price of the GTR fronts alone. And the major difference in a car with your grip and weight will be in the pad, not in the need for large rotors

2nd'd

im running R32 gtst gear all round. decent pads and slotted rotors with ducting will be more than adequate for your car.

i can out-brake 33 gtr's due to the weight of my car

[Nightcrawler]

Nope, you 3 guys above are dead wrong - Mallala is all about brakes. Forget the Eastern seaboard high speed tracks, if you don't have amazing brakes at Mallala you will NOT go well. The serious SA guys that do time attack have massive AP Racing brakes with 350mm-odd rotors, one has ProjectMu calipers/rotors, and Heslo got rid of his R33GTR brakes/rotors in favour of some heavy duty Brembo 6 pot front and 4 pot rears with massive slotted rotors of an AMG.

Get the absolute best you can afford mungy, AND throw some awesome pads on too!

[Tangles]

1.10 around mallala is impossible with what you have got / have planned.

hell mate, with my stripped R32 sedan I doubt Id get under 1min20secs. (cage, coilovers, wilwood brakes, semi-slicks) with a fully rebuilt RB26dett (87mm CP pistons, ati balancer, machined crank/collar, HKS oil pump, N1 water pump, new Cometic streetpro gaskets allround, new belts, Greddy R34 street special cams, hks camsprings, ported head, hks dumps, obx manifolds & front pipe, rebuilt turbos, 550cc injectors, Power-fc..... etc).

a realistic goal would be mid to low 1min 20secs.

[Roy]

Nope, you 3 guys above are dead wrong - Mallala is all about brakes. Forget the Eastern seaboard high speed tracks, if you don't have amazing brakes at Mallala you will NOT go well. The serious SA guys that do time attack have massive AP Racing brakes with 350mm-odd rotors, one has ProjectMu calipers/rotors, and Heslo got rid of his R33GTR brakes/rotors in favour of some heavy duty Brembo 6 pot front and 4 pot rears with massive slotted rotors of an AMG.

Get the absolute best you can afford mungy, AND throw some awesome pads on too!

Agree to disagree....if you hvae big hp, weight and grip you need big brakes. If you have lower weight, less grip and power then you can get away with far less brakes. Mallala cant be any worse then Sandown or Calder.

NO TRACK IS EVER ALL ABOUT BRAKES! The best way to improve the stopping distance of your car is mega dollar shocks that control the pitch under braking and keep all four tyres on the road over the bumps and track surface (set up properly) and very soft and grippy tyres. The stability/control under brakes and tyre grip is what stops the car....the brakes are there to just disperse the heat. Very few cars improve lap times significantly with brake upgrade alone if you leave your tyres and suspension as is. That is assuming what you have is capable, which a std R31 sliding calipers are not, but Sumitomo calipers with good pads and rotors are. IMO

Your budget should always be spent on tyres, shocks and brakes.. IMO in that order. Good tyres mask bad suspension. Good tyres help acceleration, turning and stopping. Throw in some good suspension and the car accelerates better, turns better and stops better. Throw big brakes on a car without the other two and its a waste... and major brake upgrades are along with engine rebuilds about the most expensive thing you can mod on your car which both happen to do little to improve performance

Think about an 1150kg R31 that is doing 180km/h down the straights compared to a GTR that is 1600kgs doing 220km/h on the same straight...there corner speeds can be pretty similar by 5-10km/h...no way the R31 will need as much brake as the GTR.

And back to the improving lap times...think about cars finishing the qtr mile that are 2 tenths apart at 120mph. There are several car lenghts difference...I cant think of too many practical situations where a brake upgrade will shave seconds off a single lap time...perhaps over the time it takes to complete 5+ laps but not over a lap which is all 90% of think about with club sprints

[skwiz]

Your dream of 1.10..well..hey..aim high or dont aim at all!

But seriously, aim for it. But plan to achieve smaller goals to reach that goal.

Aim to get the car ready to just drive out there. Have a good go, make sure you stick to the racing line, and see how the car handles and what needs improvement.

You have enough power, now you need to put it to the ground.

Kitto's time of a 1.20 was achieved because he thought about his setup. His brake system has been beefed up, and the right pads were selected. He chose good tyres also.

My time of 1.37 that day was shocking in my HR31..put down to crap pads and bad tyres. I still had the most fun out there though.

R33 calipers, upgraded master cylinder and booster, braided lines, slotted rotors and good tyres will get you around there under 1.30 no problem.

1.25's...well...depends how you put the power to the ground and how late you brake.

[mungy]

thanks for the info guys mayb i should hav stated the reason im going overkill on brakes, our old corolla track car's first time was 1:45, with custom built suspention and semi slicks went down to 1:40, then we got the brakes upgraded and hit 1:30's consistently. the rotors were still not as large as i would have liked and we had the brakes overheat a few times

and started to get brake fade as soon as 5 laps in and had to slow down

Dont forget guys the car will be making 280 rwkw so down the straight im thinking she would get to somewhere between 170 and 190 kmph? the later i can brake the better,

and the bigger rortors are simply there for better heat dispertion the calipers are still the standard 33GTR and the pads im thinking of using red stuff or green stuff and DOT 5.1 fluid

that combination will mean that after doing many laps ill still have 100% braking ability ( i cant stand brake fade just as u get used to the track)

Tangles, the goal has been revised.........no more time book lol, going to do the best i can then try n beat it each time im out there. my budget just wont allow me to go as fast as id like lol.

[Roy]

You are serisouly telling me that in your old Corolla you got a real 10sec per lap improvement with brakes alone? No different in tyres, cars weight, driver imrpovement, suspension etc...just brakes ? Any more detail about the cars mods and the changes to the brakes?

[R31Nismoid]

Id say the old brakes weren't in A1 and in need of pad/Rotor/fluid/line, so the comparison is of two ends of field!

[Jap_star]

you of little faith, even if i dont get 1:10 it will be close, and ill personally put the egg on your face if i manage it lol

if you can get under 1:20 with proof, send me a PM to arrage it

[Madaz]

sounds like it would be good to watch and hear in any case

[touge31]

forget bout what anyone tells you build it how you what it and have fun doin so! i keep gettin told i can't do what i want but i will prove them wrong. you should aim to do the same

[mungy]

the brake upgrage on the corolla consisded of larger ae93sx rotors with 4 pot calipers, green stuff pads forgot what fluid we used ill chase up the video from youtube and post it up here when i find it lol

[mungy]

if you can get under 1:20 with proof, send me a PM to arrage it

there will be videos lol, and im sure youll be at the track the day im there!