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What kind of grip levels should i be expecting from my new supra? i've never driven one before to give a comparison.

 

cars current running BPU, so 2 cats removed and nurspec exhaust, with 1.2bar restrictor plate but runs 0.7bar solid upto 5000rpm so thats normal. Stock wheels running 235 front bridgestone sneeker (never heard of them) and 265 rear falken fk452. One suspension mod is HSD coilovers running on soft dampening.

 

I expected it to be bad because its cold out, not frosty and wasn't even wet today just a little drew. lower gears are pointless but floor it in 4th and spins up when 2nd turbo comes in, 5th it spins up, even was squirming all over the place in 6th. Steering is also very light and unresponsive, can feel it scrubbing when turning into a junction at under 20mph. I'd say normal driving style I'm not heard footed or anything.

 

suspension geo has all been done, was setup to stock settings by the previous owner.

 

This sound normal for the conditions and the car? just doesn't give any confidence at the moment.

 

Tim

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correct me if i'm wrong but the wastgates are set to 0.7-0.8bar standard anyway aren't they. The 1.2bar restrictor ring is to just add enough back pressure to stop boost creep past that point, as we use restrictor rings in the other cars i've worked on.

 

So this is 2nd turbo comes in at 0.7-0.8bar and then slowly creeps upwards to 1.2bar by redline. Remember i don't have a boost controller on it yet as only had it 2 days. With the boost controller you can then raise the rest of the RPM range upto the lever the boost creeps to at redline. IE 1.2bar the whole time.

 

What grip levels even in the front is normal? this is shockingly bad, as in tiptoeing around everywhere as its understeering. i understeered at 20mph on the corner at my friends house, Anyway on the way home i had to drop him off i jumped in my daily drive a toyota glanza and that has 195 tyres and Toyo R1R (terrible on that car in the wet) in worse conditions, frosty and wet and same corner was no issues at 40mph. Surely the supra can't be that much difference.

 

Tim

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Rear tyre wise it sounds right, particularly with the 2nd turbo, but the fronts normally 'play ball' a little more, I can't say I've heard of those Bridgstones before so maybe the tyres aren't great?

 

Boost wise, I ran a 1bar ring in place and without a boost controller I could overboost to 1.1/1.2 from when the 2nd turbo came in (4-5k rpm) on the sort of days we have had recently (temperature wise), but on a normal day I never hit less than 0.85/0.9 bar with the 1 bar ring. This said every Supra is different some boost easily other's don't and the reasons can be all sorts. Will point out you'll have a smile on your face if/when you plumb the controller in and hit 1.2bar :)

Edited by Littler (see edit history)
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yeah i can live the rears as its to be expected, damp and the power these cars make. but fronts were shocking. but like you said i've never heard of these tyres either. take it easy i think until i get my better wheels and tyres.

 

got a racelogic unit sat into i'm waiting to fit anyway so that will give a bit more confidence.

 

oh i'm sure i will, saying that i've not used it to its full potential yet can't get grip haha. But i know the midrange will jump up alot once its being controlled to 1.2bar over just slowly creeping upto 1.2bar by redline because of the boost creep

 

Tim

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My BPU auto pulls dead on 0.65 on first tubbbie and flicks straight upto 0.95 bar when the 2nd kicks in. A bit tail happy in these conditions but after 3 years of ownership Ive never had any issues with the front. crazy pulling of from L into 2 on greasy roads :D (thats 1st,2nd,3rd for you manual whores) lol

 

I run stock 17's on a stock set up and it feels fine to me

 

Littler, a BC is on my "buy myself a christmas present" list so that extra 0.2 bar will give it some noticeable more kick??

 

got a racelogic unit sat into i'm waiting to fit anyway so that will give a bit more confidence.

 

 

Tim

 

aftermarket TC is for fannys :D man up goddam :jester:

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My BPU auto pulls dead on 0.65 on first tubbbie and flicks straight upto 0.95 bar when the 2nd kicks in. A bit tail happy in these conditions but after 3 years of ownership Ive never had any issues with the front. crazy pulling of from L into 2 on greasy roads :D (thats 1st,2nd,3rd for you manual whores) lol

 

I run stock 17's on a stock set up and it feels fine to me

 

Littler, a BC is on my "buy myself a christmas present" list so that extra 0.2 bar will give it some noticeable more kick??

 

It will do yeah, more so due to the boost delivery, Adi (letmeshowyou) has fitted one to his with the cats in place and even just boosting to stock levels has improved due to the gain feature (how quickly the turbos spool).

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Was the geometry setup done with the suspension adjustments and tyre sizes as they are now?

 

I'm overdue a geometry setup and just put some 245s on the front (225 before) and changed my suspension setup (OEM Bilsteins and Tein springs for BC coilovers) and I'm not having your issues. Even in the -6C Aberdeen ice fest we have just now!

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I wouldnt buy one Tim :)

 

If I was given it maybe, but it has stock TC, effective or not. Drive to the conditions and ability and you wont need any electrcal gizzmo's to keep you on the road.

 

yeah well i'm in a situation where i get them cheap, and you've obviously never driven a car with this unit, i had one on my 450bhp mr2 and it saved my life countless times. i also found the car was much faster in the curves

 

Tim

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Check your tyre pressures & check tread across the whole tyre (without trying to teach you to suck eggs). At 20mph even in this cold (remember it was -3 in parts of London last night) you shouldn't lose much traction, though saying that if you turn too harshly even at 20mph you will upset the balance, taking into consideration these are heavy cars.

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I expected it to be bad because its cold out, not frosty and wasn't even wet today just a little drew. lower gears are pointless but floor it in 4th and spins up when 2nd turbo comes in, 5th it spins up, even was squirming all over the place in 6th. Steering is also very light and unresponsive, can feel it scrubbing when turning into a junction at under 20mph. I'd say normal driving style I'm not heard footed or anything.

 

You're not heavy footed but you give it enough to spin it up in 5th?? Best advice I can give is don't boot it so hard, don't want to become another winter crash story...

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The weather "probobly" has something to with the lack of traction, surely you dont try and hoon around in this weather, there's a reason why so many owners take the supra off the road in the winter, if your gonna use it expect not to be able too use the full extent of the power available.

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I can nail my 400 hp auto tt and it just grips and goes even in this cold weather

as long as the rds dry and no frost ice etc

 

I can't see how you spin the rears in 5th to be honest unless your driving on a very

low grip surface or there is something wrong with either the tyres or set up on the car.

 

Problems at 20mph seem to imply that something is wrong with the geometry/tyres etc

 

I'd get it booked in some where to check the geo, a lot of places will do a check for

a small fee or even free.

I just had my landcruiser checked at a Formula one Autocenter with the supertrack system for free.

 

It had just been set up on another system earlier in the day

and wasn't right so its worth checking yours

Edited by Dnk (see edit history)
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