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Discussion Starter #1
Hi Guys, please remember I’m used to the steering and rwd of a lotus ... so the A45S is a bit of getting used to so forgive me if I’m being stupid with this post!

However under very hard acceleration the car seems to wobble, like I’m tramlining side to side, is this normal? Is this torque steer? Or something I might want to get checked out?
 

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It's exactly what I've found and clearly everyone else experiences the same. It's normal as far as I can see but didn't happen on the original A45 while it was stock. It's the way the torque transfer happens but it shouldn't cause that and I suspect it will be especially noticeable if I get a stage 1. I need to try it with the ESP dialled up, as I have it in sport, and see if that makes a difference.

Take a look at this part of the thread and the video I posted W177 A45/A45S Print and Video Reviews
 

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A lot of videos on that page actually. It's this one 15 mins in watch his arms.
 

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Yep that’s it ... very unnerving and really got me a bit stirred with the car. I was just getting confident with it and now feel a big knock back.

I didn’t have this with my R35 which is the only other 4WD car I’ve owned.

Anyone spoken to MB about it?
 

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Anyone spoken to MB about it?
I haven’t and doubt if any of the other guys have. I used to get this on my tuned A45 in the wet. MB must be aware of it and you do get used to it I noticed when I was out giving it a good thrashing yesterday. But it was bone dry so in the wet it might be different and “difficult“.
 

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Does it not depend on the road camber etc, on others cars I noticed it but not eve time?
I find it happens on any surface if you floor the throttle but it’s a lot less pronounced on smooth tarmac.
 

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I find it happens on any surface if you floor the throttle but it’s a lot less pronounced on smooth tarmac.
I always drive in manual mode never auto !i think when u shoe the car and it has to drop down a few gears and it gets the chance to build the boost up maybe get this problem
To be honest you only think your A45S is quick standard wait to you remap if I always say I must buy a harder wall tyre as these Michelin can give u the wobble feeling especially at high speed
Always for like a quarter of a second then they tighten up on the wall again

are you driving the car with soft suspension when this happens ?
 

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Discussion Starter #9
It’s generally in sport setting on suspension and sport+ everything else... it is on hard acceleration going up gears (via paddles). I’m going to check my tyre pressures tomorrow especially given the recent weather.

I’ll report back, I must admit the point ref tyre walls may have some merit, I do remember once going from Dunlop to Pirelli in the GTR and it was very uneasy so much so I changed back to Dunlop’s (stiffer tyre wall) three days later.

That said I’m hoping it’s tyre pressures out of kilter!
 

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I always drive in manual mode never auto !i think when u shoe the car and it has to drop down a few gears and it gets the chance to build the boost up maybe get this problem
To be honest you only think your A45S is quick standard wait to you remap if I always say I must buy a harder wall tyre as these Michelin can give u the wobble feeling especially at high speed
Always for like a quarter of a second then they tighten up on the wall again

are you driving the car with soft suspension when this happens ?
We just have the standard suspension without the aero plus pack. But I agree about the PS4s' they are soft walled compared to the Conti 5's we originally had on the A45. I will consider the Conti 6.

I think what the cause of the "trampling" is is the sudden torque transfer to the rear wheels when flooring the throttle and then the fancy hardware in the back waking up and juggling it around i.e. it's slightly slow hence its noticed and requires steering correction.
 

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It’s generally in sport setting on suspension and sport+ everything else... it is on hard acceleration going up gears (via paddles). I’m going to check my tyre pressures tomorrow especially given the recent weather.

I’ll report back, I must admit the point ref tyre walls may have some merit, I do remember once going from Dunlop to Pirelli in the GTR and it was very uneasy so much so I changed back to Dunlop’s (stiffer tyre wall) three days later.

That said I’m hoping it’s tyre pressures out of kilter!
You can check the pressures on Mercedes Me. Looking at mine on the app they are currently F 46 B 42. I have been getting this from the day I finished running the car in and could floor the throttle. I think with @Irish boy running the car in manual I assume the rear axle is probably always taking some of the load and hence primed and not likely to cause this problem.
 

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You can check the pressures on Mercedes Me. Looking at mine on the app they are currently F 46 B 42. I have been getting this from the day I finished running the car in and could floor the throttle. I think with @Irish boy running the car in manual I assume the rear axle is probably always taking some of the load and hence primed and not likely to cause this problem.
Seems a little high to me. Just checked mine.
67763227-8727-43E5-A612-A81B36ECB9AD.png
 

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I was going to say I’ll have to go for a lockdown cruise to check my eyesight but then I thought I’d check the pressures on the flap
5864
 

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I was going for the lower end of up to 168 mph of course and the heat after a good thrashing increased the temperature when I was putting it in the garage.

What do others target for pressure.
 

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Discussion Starter #17
I checked my pressures today 44 front 41 rear. I've reduced them down to 41 front and 38 rear especially given the current weather. I'll see if it makes any difference at all...
 

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I've already posted my experience which I'm not sure is what you described. I felt a bit if fishtailing during launch control, on slippery pavement, and I blame it on the lack of front grip which naturally transferred all the torque to the rear, making the car rwd. Felt great, but it did take a little counter steer. Mind you I had esp-sport, it wasn't off.

Anyways, mine came with 300 front and 280 rear which is ok I think. Maybe if I went with 280/260 I could have a little more grip but I just haven't bothered yet, car has tons of grip as it is. With that said, the PS4S isn't my preferred choice and once they wear out I'm going with Yokohama Advan Neova AD08 RS which is a semi-track tire. I had the AD08 R on my previous two cars and it was outstanding, had very quick warm up time which is ideal for road use and at the track they were nearly neck and neck with pure semi-slicks such as the discontinued Toyo R888, according to a time attack comparison. Now the AD08 R has also been replaced by the AD08 RS just like the R888 has been replaced by the R888R. To be honest I could go with either one but the Yokos are miles better in the wet, I know because I had the R888 too. It was indeed slightly slower in the dry though, time attack was legit. I also had the Michelin PS Cups (the first one) which was great at the track but took forever to warm up, not ideal for the road. So anyway, the PS4S is a very decent tire and I hate to just spend money on a brand new set before at least a year.

I also have some unpleasant news, the only Brabus dealer is about 500km away, which means I'm gonna have to stay a couple nights, not only to rest, after the tune I gotta give the car a little time, see if anything comes up before I head back home. Stay a couple nights at a hotel that is. And that I'm afraid is gonna have to wait until I feel it's perfectly safe. I just don't wanna take the risk until we have a vaccine. This summer we aren't going anywhere I'm afraid. Full-day trips and that's it, we just don't wanna stay anywhere. So I'm thinking, I can get the tune next summer which I believe will be safe, and by that time I might as well upgrade tires and get my Yokos.
 

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I just don't wanna take the risk until we have a vaccine.
I entirely agree. Especially as we are I believe on the home stretch to a vaccine. But I do have a large family holiday house booked in the UK for August and I'll need to decide in the next few weeks about whether to pay the remainder of the money for it.

Specifically about Brabus. I emailed them again on Thursday and asked where the May/early June launch date came from as it couldn't have been made up. Anyway to cut a long story short, and giving the benefit of the doubt about things being lost in translation, they said "please have a little patience we will keep you informed"
 
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I entirely agree. Especially as we are I believe on the home stretch to a vaccine. But I do have a large family holiday house booked in the UK for August and I'll need to decide in the next few weeks about whether to pay the remainder of the money for it.

Specifically about Brabus. I emailed them again on Thursday and asked where the May/early June launch date came from as it couldn't have been made up. Anyway to cut a long story short, and giving the benefit of the doubt about things being lost in translation, they said "please have a little patience we will keep you informed"

forrester go and Enjoy your holiday if you and your family have a healthy immune system you have nothing to worry about vaccines and do not take a vaccine is made up of a baby fetus’s and mercury and bleach and what ever else they want to put into you go do your research on it
👊
 
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