Lexus IS350 GT300 Base Model

Discussion in 'GT6 Tuning' started by Thorin Cain, Jan 9, 2014.

  1. Thorin Cain

    Thorin Cain Premium

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    Some friends and I were racing GT 300s at 500pp and there seemed to be something missing from the line-up. The usual suspects were out in force, RX-7s and BRZs all over the place, even the odd Garaiya....buy no IS350 to be seen.
    So I decided to give it a go, After a few races round GVS, Apricot Hill and Trial Mountain I had been tweaking away and came up with a pretty handy little tune. Well, it worked for me. Hope it can be of some use to someone else!
    IS350 colour.jpg
    Weight:1150kg
    Power:304BHP
    PP:500

    Tuned with DS3, stick control on 0 sensitivity. ABS:1, other aids off.

    Tyres: Racing Hard
    Suspension:
    Ride height: F 45 R 50
    Spring Rate: F 15.00 R 13.50
    Compression: F 2 R 3
    Extension: F 3 R 3
    Anti-Roll bars: F 2 R 2
    Camber: F 0.0 R 0.0
    Toe: F -0.10 R 0.00

    Brakes:F 3 R 1

    Transmission:
    Set final speed @5.000
    Auto set top speed to 112mph (180kph)
    set individual gears.
    1. 3.518
    2. 2.594
    3. 2.006
    4. 1.610
    5. 1.340
    6. 1.158
    set final gear @ 3.500 for top speed of 152mph ( 245kph). Change top speed to suit each track by final gear only.

    LSD: initial 6, Acceleration 6, Braking 8.

    Power Limiter: 95.9%

    Downforce: F 250 R 400.

    Also ran quite well on all racing tyres at 500pp as well as at 540pp with stage 3 engine tuning. Transmission needs different ratios for 540pp though.
     
    Last edited: Feb 2, 2014
  2. Whiterice83

    Whiterice83

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    110
    I tried this tune out and like it quite well. It dropped my lap time on nurburgring gp/f by 3.9 seconds and the car has far more control at low speeds thanks.
     
  3. Thorin Cain

    Thorin Cain Premium

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    Thanks for trying it out, glad it was helpful.
     
  4. athol

    athol

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    I've got this tune and like it very much. Used it to good effect earlier on doing some of the Int A races. Works well at lower pp too so long as you change the gearing to suit. I may loosen the diff a little as I like the rear to slide a little but other wise its very solid and stable :)
     
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  5. Saber186

    Saber186

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    Liked my lil IS350 so much I even bought the WedsSport one..and your tune has made them even better..Thank you for a great tune
     
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  6. Thorin Cain

    Thorin Cain Premium

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    Thanks for the feedback and the kind words @Saber186 and @athol. Glad you guys liked it.
     
  7. Badger66

    Badger66

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    This tune also works really well at 600pp:) just tried it on N24...very responsive...thank you:)
     
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  8. Thorin Cain

    Thorin Cain Premium

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    Thanks Badger!:tup: I'll give it a try, don't think I've ever taken it by 550pp.:cheers:
     
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  9. Badger66

    Badger66

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    It really is Awesome at 600pp i just used it on the International B midnight racers N24...time 8.46...won by 42sec...that i thought wasn't a bad time considering most are 650pp cars your'e up against:)i just changed the brakes to F.9 R.6..thanks again it really handles well on here:)
    Forgot to say this car sounds amazing:)
     
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  10. Thorin Cain

    Thorin Cain Premium

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    Nice, I'm going to go do that right now and try it out.:)
     
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  11. cbarbosa

    cbarbosa Premium

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    @Thorin Cain,

    This is amazing, I was just looking for tunes for this car, when all of a sudden... BAM! Here it is! :tup:
    Im curious about this car, so will try the tune asap!

    So Mr. Thorin, sir, forgive my silly pre-build question:

    Why "0" at controller SS? Im a DS3 player and I use CSS at 7 almost every time... Isn´t hard to steer faster in slow tracks?

    Many Thanks. :cheers:

    EDIT: You are right, the R390 desserves at least 600PP, but at 550PP it is glued to the road... :p
     
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  12. Thorin Cain

    Thorin Cain Premium

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    That was fun:D

    I did the full tournament a couple of times, just for :lol: You're right it does work pretty well at 600pp but there's no way they're running at 650pp levels. they're probably about 590-600 tops I reckon.

    The car feels a bit twitchy in some of the high-speed areas on The Ring though. I'm going to have to have a little play with it and get a nice little 600pp version done, might even leave it on Hards. There is way more time to be had out of this car now with the physics changes and all (Not to mention another 6 months learning the craft). I like the brake balance by the way, works really well:tup:
     
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  13. Thorin Cain

    Thorin Cain Premium

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    Hey,

    It's an oldie alright. She's been tucked away in the recesses of the forum for ages until Badger dug it up. Hope you enjoy:)

    About the CSS, I don't know, just got used to it. I've been using about 2 or 3 since I used a couple of Ridox's replicas and just never put it back. 7 is way too much for me but I should have put this up a long time ago.

    R390: :lol: Yup.

    Cheers again cbarbosa:cheers:
     
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  14. Badger66

    Badger66

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    Those midnight races are my favourite and everytime i get a new car around that pp mark i always give it a go on those and really enjoyed your tune....Looking forward to having a go with your 600pp version when you do it and thanks:)
    You're right they cant be 650pp.. you get to much of a lead...they must be around 600pp ish:)
    The brake balance is the same as what you came up with...but i thought that the extra power you would need to stop a bit quicker:) thanks again Thorin
     
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  15. FSportIS

    FSportIS

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    526
    Haha, I drive the production Lexus IS350 everyday in real life and great to see this GT3 tuned IS350 car being mentioned on here. It is so underrated in this game lol.
     
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  16. LasseLarsen

    LasseLarsen

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    Thanks. i've been making my own, simple tunes. but this wil probably work better :D
     
  17. Thorin Cain

    Thorin Cain Premium

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    Hope it helps. Just remember if you increase the power, increase the brakes too. Thanks for trying it:cheers:
     
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  18. BenMillard

    BenMillard

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    Just used this in an unlimited tuning online club event. 6 minutes qualifying, 1 hour race around Apricot Hill. It was outstanding!

    Everyone was using Racing Soft tyres. No SRF, TCS 2, ABS 1. DS3, chase camera, manual gears, right stick gas, L2 brake, steering 7

    Qualified 3rd and had 10 second lead starting the final lap, despite a big early crash and pitting completely out of sequence on the wrong strategy at first. :tup:

    Lexus IS250 GT300 Base Model '08
    BenMillard Changes
    Oil change: Yes
    Chassis: Standard
    Brakes: 1 2

    Power: 665bhp 72.4kg/m
    100%
    Stage 3 Engine
    High RPM Turbo Kit

    Gearbox:
    3.275
    2.425
    1.875
    1.600
    1.400
    1.250
    2.750

    Downforce:
    350 450 (max front, rear = front + 100)
    I tried a couple of other minor changes but made it worse for this track. How come the soft anti-roll bars work for this car? Seasonal tunes usually have 7 7 ARB these days but that just made it slide. Naturally ultra stiff chassis?

    The fairly hard springs remind me of a @PASM tune for the Mercedes-Benz CLK Touring Car '00 from a WRS event a while back. Suited the fairly fast sequences in Apricot Hill but was very sensitive to that 'groove' where PD want you to drive.
     
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  19. Thorin Cain

    Thorin Cain Premium

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    Thanks for the feedback :cheers:. And Congratulations on your win! :D:tup:

    To address your questions...
    I can't remember how stiff the springs are in relation to the max amounts, it's been a while since I've used this car. But if they are very stiff (in the highest 1/3 of the slider range), that would be a good indication of why the low ARB values work.
    Generally speaking stiff springs work better with softer ARBs and vice versa. The ARB's job is to tie the motions of inside and outside suspension together in the bends, meaning as the left side loads up (compresses) in a right hand bend, the ARB is responsible for making sure that right side suspension (inside) will raise (extend) by the same amount. Thus keeping the car balanced and limiting the amount of load transferred to the outside wheels in the bends.
    If the springs are stiff there will be less compression on the outside suspension during load and the car will be susceptible to bouncing off kerbs/bumps in the track if the inside wheel runs over these. If a stiff ARB is used with stiff springs, there is not enough movement left in the suspension to keep all 4 tyres in contact with the track.
    Soft ARBs allow more movement inside to outside, hard ARBS allow less movement.

    Most of the TT tunes I've tried with higher ARBs normally run with pretty low spring rates (lower 1/3 of the slider), utilizing the maximum amount of mechanical grip, but these springs are normally not stiff enough to withstand the cornering forces, maintain good lateral balance and keep the car as level as possible. Then the ARB is used to control the lateral loads on the car and keep it level in the bends.
    It's really due to the way people got use to tuning when camber didn't seem to effect the lateral load transfer (pre update 1.09). A lot of TT tunes I have seen and tried, have springs which are good for controlling dive and squat, but still allow too much movement laterally. The advice I have seen most often on the GTP tuning forum, is that springs should be stiff enough to control all unnecessary body motions, but should not be too stiff that they won't allow the car to rotate. This usually leads to people leaving the springs too soft to control the lateral movements and then having to compensate by having really stiff ARBs.
    IRL (and it works in GT6 too BTW ;)) the advice given for selecting spring rates, is to go stiff enough to control all body movements even if it does leave the car too stiff to rotate enough :crazy:. Then use that nasty camber setting no-one seems to like to get the rotation you need, adjust toe angles to suit the camber used by counteracting the effect of a cambered wheel when travelling in a straight line (A wheel will naturally gain negative camber and slight toe-in during compression and will do the opposite when extending), which will vary depending on amount of camber used and any ride height differences (rake) because this alters the front and rear caster angles (the caster angles effect the camber angles during compression and extension of the suspension). With the final touch being to adjust the ARBs to control/tie together the inside/outside weight transfer.

    Bet that was a longer answer than you were expecting :sly: Yeah me too ;), hope it helps.:gtpflag:
     
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  20. coryclifford

    coryclifford

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    If the outside tire is being compressed, the ARB will lift the inside tire (compress). Working as a torsion bar, it's resisting the twist. You said extend.
     
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  21. Thorin Cain

    Thorin Cain Premium

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    If the inside lifts, the suspension is extending. On the data logger it is easy to spot. During level travel both springs will show level at 0. In a right turn the left side compresses (-value for spring travel) and the right side will extend (+value for spring travel).
     
  22. coryclifford

    coryclifford

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    Well yeah, but the sway bar is there to make it do the opposite. Let's take my '94 Civic Autocross race car as an example. With an ARB in place, the inside tire lifts up in the air much more than without an ARB in place, front or back. I lose traction and the inside front tire peels out more then grips. Remove the ARB and now I've got traction on the inside tire. Same goes for the rear end. Big thick ARB on there to intentionally lift the inside tire so there's less overall grip in back, for better rotation. I also ran 1.5" wider front tires and different compounds front to rear.

    Maybe we're saying the same thing but reading it differently?
     
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  23. Thorin Cain

    Thorin Cain Premium

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    Ah my bad, I see what you are saying :tup: thanks for clearing it up :cheers:
     
    Last edited: Jul 27, 2016
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