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Hello

I will either tune my rb20 det to 400hp with supporting mods, or buy a rb25 det and tune it to 500hp or maybe even a 26 and tune to 500hp.

I have 17" 225/40 wheels/tires on the front. Want to change to 17" 235/40.

17" 245/45 wheels/tires on the back. Want to change to 255/40 if can fit.

I am going to get the Nismo 2 way LSD. I have HKS coil overs.

My hicas works fine.

Is there anything else I can do to make sure I am getting power to the ground?

I dont want to go sideways unless I want too, and what to make sure I can handle curves, take offs, and driving well since I have rwd car.

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HICAS has nothing to do with it. Delete it and things will actually be better anyway.

Use the same size tyres all around. No sense at all in staggered fitment on an R32. 235/45-17 on 8" rims with +35 offset works well. 245s will also fit, but will bag a bit on 8s. 255s you're definitely talking 8.5-9" rims and then it becomes harder to fit everything under the guards without unwanted scraping or rolling. Look at the wheel sizes thread in Suspension, braking and tyres for guidance about what fits.

But more important than the width of the tyres is the tyre itself. It is better to use a narrower tyre with sticky compound and good construction than to use a wider cheap nasty tyre.

Alignment and bush condition are two very important things not to neglect. You can have $10000 Ohlins coilovers on your car and it still will not hook up properly if the rest of the suspension is flailing around because it's f**ked. Similarly, stacks of rear negative camber will not help (forward) traction at all.

Keep in mind something important. 400 engine HP on a Skyline is not much power really, but on an RB20 it tends to mean you have no torque followed by no torque followed by no torque then it comes on boost you make 400HP worth of torque and it breaks traction. There is little you can do to make that work. RB25s come onto boost more gracefully (at the same power levels) and feel much faster, simply because they have more torque and start making vehicle speed before they come on boost. But add another 100HP and you're still going to be able to break traction freely.

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HICAS has nothing to do with it. Delete it and things will actually be better anyway.

Use the same size tyres all around. No sense at all in staggered fitment on an R32. 235/45-17 on 8" rims with +35 offset works well. 245s will also fit, but will bag a bit on 8s. 255s you're definitely talking 8.5-9" rims and then it becomes harder to fit everything under the guards without unwanted scraping or rolling. Look at the wheel sizes thread in Suspension, braking and tyres for guidance about what fits.

But more important than the width of the tyres is the tyre itself. It is better to use a narrower tyre with sticky compound and good construction than to use a wider cheap nasty tyre.

Alignment and bush condition are two very important things not to neglect. You can have $10000 Ohlins coilovers on your car and it still will not hook up properly if the rest of the suspension is flailing around because it's f**ked. Similarly, stacks of rear negative camber will not help (forward) traction at all.

Keep in mind something important. 400 engine HP on a Skyline is not much power really, but on an RB20 it tends to mean you have no torque followed by no torque followed by no torque then it comes on boost you make 400HP worth of torque and it breaks traction. There is little you can do to make that work. RB25s come onto boost more gracefully (at the same power levels) and feel much faster, simply because they have more torque and start making vehicle speed before they come on boost. But add another 100HP and you're still going to be able to break traction freely.

I use Federal 595ss on the front and have some Pirelli's Cinturato P-7's on the back. THe Federals are pretty good and the Pirellis not too bad, good gripe.

I will probably go with all Federals when its time to change tires. The newer ones of course since the 595ss are discontinued.

I don't mind rolling the inner fender to make the tires to fit.

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Don't install a 2 way, buy better tires

Don't worry too much about bigger rims and buy better tires

Don't lower the car more than a couple of inches... and buy better tires

once you have better tires, put better coil overs in it.

....

J.

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Don't install a 2 way, buy better tires

Don't worry too much about bigger rims and buy better tires

Don't lower the car more than a couple of inches... and buy better tires

once you have better tires, put better coil overs in it.

....

J.

I understand buying better tires,

but why no 2 way? Whats wrong with HKS? Not sure how much car is lowered. I haven't messed with the height, the car is still the way it was when I got it. Already had the HKS Hyper D's on them. Its lowered some but not too much. Came that way.

I know about the big brand tires, Dunlop, Yokohama's, etc but I am in Japan and they charge a premium for the really really good tires from those companies.

From my experience the Federal's are good. Any model tire that is good that you can suggest?

Don't want to use semi slicks for everyday driving because its rainy season now and I don't want to wreck.

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Federal 595 SS are rubbish.

You're in Japan, get Advan Neova tyres, should be cheap as chips for you.

A 1/1.5/2 way mechanical diff will help put the power down, your stock viscous rubbish will end up splitting the torque 90/10 instead of 50/50 like a mechanical diff

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Oh, no KU36 please, they aren't a great option.

I really like my new Bridgestone RE002/003's, great wet performance even in torrential downpours when you would normally be aquaplaning like mad.

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I wouldnt recommend AD08R's unless you can put some decent heat into them, great for track but not always great on the roads if you want lots of grip all the time.

RE002's were a good soft compound for me and also really love the Advan Sport V105 as a street tyre.

horses for courses really.

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I wouldnt recommend AD08R's unless you can put some decent heat into them, great for track but not always great on the roads if you want lots of grip all the time.

That's actually one of the things I like about them. Get them warmed up on a spirited drive and they stick nice. Drive around familiar streets at home and you can skid them a bit without wearing them out!

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We removed our AD08's off the front of one of our cars and put the new Federal RS-RR (extra R).

Cant believe the grip levels now.....wont be going back to AD08's in a hurry.....

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We removed our AD08's off the front of one of our cars and put the new Federal RS-RR (extra R).

Cant believe the grip levels now.....wont be going back to AD08's in a hurry.....

how old were the ad08's? what were they used for until you changed them?

at half the price, the RS-RR's seem to be a clear winner.

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Car is a Supercharged S2000 (1200kg) laying 250Kw at the rears.

Traction was great with AD08's In summer or with hard driving on windy roads, but all other times you needed to work them to heat them on the street, other wise, slide city.

RS-RR.....think AD08's when hot.....but its cold and you have not heated them yet....

Currently the RSRR are only on the front, now its point and shoot like a go kart, sticks like anything...the rears (ad08 still on) just follows the front while sliding.

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Our AD08's always needed some heat even when new.

Id agree that too many heat cycles dont do them any good and they fall off with mileage.

Will be interesting to see what the RS-RR's are like when old, at the moment they are outperforming the AD08's new for new.

Would be a perfect street car hill climb tyre, sticky with little heat.....will also monitor wear rate on them.....

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Time will tell.

Went for some high speed late hard braking today, rear started to controlably slide sideways without locking when braking in a straight line, fronts were planted.

AD08's are on the rear.....they are at the point where i would call them dangerous when cold. (and heat cycled a few times too many)

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