[R35GODZEELA]

Hello guys,

New to this forum and need some major help. I just put on some ferrada wheels yesterday 20x10.5 +25 front 20x11.5 +15 rear wrapped in nitto nt555 g2 315/35/20 rear and 275/35/20 front. I drove it last night and the vdc blinked twice and went away then again twice and went away and car felt like it was in limp mode. The AWD light came on as well and I turned off and on the car and it went away. There were no more lights on at all after that. Drove today and while WOT from first gear it was major lag like it was trying to push but it wasn't. It was pushing from 8-10lbs boost back and forth until shifting into 2nd gear and going to 15lb boost and then doing the same lag like it's cutting off and on off and on until recline. 3rd + gears are all fine. I am thinking it's due to the tires? I hope I did not mess my tranny up. I don't know what to do. I was looking at tire diameter issues but can anyone help on this if they have experienced any major lag in 1st and 2nd gear to a point where you can feel the car go to 3k rpm to 4k rpm back down to 3k rpm then up again after putting on new tires and wheels? Will changing the rear tires to 295/35/20 fix it? Or is my tyranny messed up now? Thanks guys!!!

 

[GT-R Marine]

According to the nitto tire website your rear tires are 28.62 diameter and the fronts are 27.6. I believe that is too much of a diameter difference front to rear for the GT-R AWD system to handle.

If my calculations are correct that is a 3.4% tire diameter difference front to rear which is beyond the 1-3% threshold for the GT-R.

You need to change your tire sizes so they are within 0-3% diameter difference. The closer you can get to 0% the better.

 

[R35GODZEELA]

Thanks Marine! What about the codes it's throwing off? Also, the whole lag part without any codes on which I forgot to mention in original post. Thanks for any input!

 

[GT-R Marine]

Your GT-R is going into limp mode to help prevent transfer/transmission damage. I would avoid driving it until you get better matched tires. If you do have to drive it then take it easy and try not to drive too far.






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[Python]

listen to this mans advice

 

[R35GODZEELA]

Thanks my man! I will get probably 285 or 295 instead for rear. The whole lag is still concerning me though because there weren't any lights on when it was doing that.

 

[GT-R Marine]

I would recommend the 305/30/R20 for rear. The overall diameter for this size is 27.24 and your current fronts are 27.56 (minor size correction from my original post). This is within the GT-R's AWD tolerance. Another good rule of thumb is you don't want to go over .4 inch diameter difference from front to rear.

If you went with the 285/30 or 295/35 Nitto offers you would go over the half inch front to rear difference if paired with your 275/35s.


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[R35GODZEELA]

Thanks Marine! Sorry to bug but one last question. The whole lag and stuff I mentioned in the original post, any input on that? That's without any lights on which started after putting the wheels on. Do you think I damaged anything? Or you think it will go away once correct tires are on there? Thanks once again

 

[Goonthree]

Get 275/40/20 front is another option

 

[GT-R Marine]

The lag was just system lowering your boost. When this happens you won't get any warning lights but you will definitely feel the difference. It happened to me before after getting crappy gas. I don't think you damaged anything but I would avoid driving on them as much as you can. Once you put better matched tires on you shouldn't go into limp mode anymore.

Also, I checked a little further and if you wanted to have a perfect match front to rear with your tires you could go with 275/40 front and 315/35 rear. Both are exactly the same diameter at 28.66!




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[R35GODZEELA]

Perfect! Thanks everyone. Will be getting the 275 40 front tomorrow.

 

[PSIxGEO]

Currently running a 285/35 on a 10.5 up front, and 315/35 on a 12 in the rear..no lights or wonkiness

 

[Danial]

The lag was just system lowering your boost. When this happens you won't get any warning lights but you will definitely feel the difference. It happened to me before after getting crappy gas. I don't think you damaged anything but I would avoid driving on them as much as you can. Once you put better matched tires on you shouldn't go into limp mode anymore.Also, I checked a little further and if you wanted to have a perfect match front to rear with your tires you could go with 275/40 front and 315/35 rear. Both are exactly the same diameter at 28.66!Sent from my iPhone using Tapatalk

 

[Danial]

But the 315 will not be touching the body and fender ? I have the same in my car and getting noice plus the same earring for tyre wrong size and AWD clutch high temperature . Any advise ? @gt-r marine

 

[Ruthlesz]

It doesn't have to touch anything. The AWD system requires proper ratio sizes for it to work.

 

[Maxikeem]

What tire size are you running?

But the 315 will not be touching the body and fender ? I have the same in my car and getting noice plus the same earring for tyre wrong size and AWD clutch high temperature . Any advise ? @gt-r marine

 

[smart water]

Currently running 285/35 on 10j, 325/30 on 12. never had a issue

 

[adam.henshaw7]

Hey everyone,
My GTR is 11mm too low, police got me..
Can't get hold of any used or new stock springs and coilovers cost too much to certify. So I was thinking how can I get more ground clearance and thought I know I can increase overall tyre diameter haha (btw

shock tower spaces aren't legal here in Australia).. I've left the profile of the tyre as standard and changed the width therefore changing wheel size. Front from 255 to 285 and rear 285 to 315. The side wall height is 10 and 12 mm bigger. This should raise my ground clearance hey? It's 2.8% and 3.3% size increase.

I haven't drove it yet .. get them fitted next week.

Will this work for me? I only want this setup to pass inspection. To get car back on road.

After that I'll buy some proper tyres like Michelin pilot sports instead of these kinforest kf550 's haha.

Cheers
Adam

 

[droptopp]

Too low ? Gheezh what’s next tires too wide ?

 

[White_turbo]

How does the police know your car is 11mm too low? 😅