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RT660 275 vs 295 Advise

TeeLew

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Well, here's my logic. You don't really want those tires for the street. They'll hydroplane in the rain like a motherf. And not usable in the cold you'll ruin em. They are only good for the track or warm, dry summer weather. Depends where you live. But either way they will wear out fast on the street and you're wasting a lot of money. You really need two sets of wheels for street and track.

So if you go to extended studs for 305s, you're stuck with those studs sticking out in the front which will look weird when you go back to your street wheel and tire set.

I opted to not do the extended studs and run MRR M600 +24/+50 offset. So i was able to fit 11" wide and 305 RE71R. But, then I can't rotate the tires. Decisions decisions. They're amazing but I probably would've been fine with a 275 tire and rotatable setup and therefore also no need for extended wheel studs.

I like the look of the extended studs. If you don't like the extra stud sticking out, run a spacer on the street. I run 275's all the time. I don't find them to hydroplane excessively as long as the tires have tread and we've actually had some rain in CA lately to make this a reasonable read. The car came with 265's which were garbage, so it's better than that, at least. The stock Pirelli's were evil.

The wider tires tend to tramline more and I agree it's better to have 2 sets. My M600's have 305's on them and are all +50, so rotating is easy. They're just fun wheels, though. I run the stock one wheels with 275's on the street.
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NightmareMoon

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May be a stupid question, but since we're here I'll ask it haha. If I did go 19x11 with 305s, I would need to get extended studs on all 4 points right? Not just the front, I'm assuming all around right?
Just the front. The rear can take a standard 11" ET50-52 with a 305 tire without issues.

For the Falkens, they're pretty stuff, so I don't honestly think they'll suffer being stuffed onto wheels a little bit to narrow like a normal street tire would... HOWEVER, I'm not so certain you won't rub, because the they're effectively as wide as many 305 tires.

So stick to the 275, or bite the bullet and do front axle extended studs and spacers and camber plates (if you don't already have them)... and open lugs for your street tires) and you can run a 305 on an 11 square.

For HPDE, its not really a big reason to go to the wide 305s unless your ego really NEEDs to go a half second faster. Mine does :p
 

Bluemustang

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I like the look of the extended studs. If you don't like the extra stud sticking out, run a spacer on the street. I run 275's all the time. I don't find them to hydroplane excessively as long as the tires have tread and we've actually had some rain in CA lately to make this a reasonable read. The car came with 265's which were garbage, so it's better than that, at least. The stock Pirelli's were evil.

The wider tires tend to tramline more and I agree it's better to have 2 sets. My M600's have 305's on them and are all +50, so rotating is easy. They're just fun wheels, though. I run the stock one wheels with 275's on the street.
Really. My RE71R are undrivable in moderate rain over 45 mph. Maybe RT660 improved the design by it doesn't seem so by the looks of the tread design.
 

TeeLew

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Really. My RE71R are undrivable in moderate rain over 45 mph. Maybe RT660 improved the design by it doesn't seem so by the looks of the tread design.
No, my 275's are just road tires, not fun ones.
 

NightmareMoon

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Really. My RE71R are undrivable in moderate rain over 45 mph. Maybe RT660 improved the design by it doesn't seem so by the looks of the tread design.
Well the big blocked tread design doesn't help, but the RT660 compound is particularly bad for wet surfaces and associated cool tire temps.

Its not even slippery in a fun playful way, its just freaking dangerous.
 

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MarquanTR

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I personally don’t think the studs look weird. Also this is 305/30/20. I’d say get the studs/spacer and go that route. I started with 285 square on 20 x 10 and now I’m on 20 x 11 with 305 square and the 20 x 10’s will be listed here shortly lol

IMG_0589.jpeg
 

MarquanTR

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For further information, you will rub a little bit with 305/30/20 on dual rate magneride springs, even with -2.9 camber up front. I’m installing Steeda’s front ride height adjustment kit to give me the .5” back in the front to alleviate it. Which also means I’d be able to use 305/35/19 tires instead of 305/30/19 tires for the summer. Just wanted to put this out there just incase anyone wanted to have a good spring like the dual rates but wanted the height the same upfront due to tire clearance or splitter clearance!
 
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OXWhiteGT

OXWhiteGT

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For further information, you will rub a little bit with 305/30/20 on dual rate magneride springs, even with -2.9 camber up front. I’m installing Steeda’s front ride height adjustment kit to give me the .5” back in the front to alleviate it. Which also means I’d be able to use 305/35/19 tires instead of 305/30/19 tires for the summer. Just wanted to put this out there just incase anyone wanted to have a good spring like the dual rates but wanted the height the same upfront due to tire clearance or splitter clearance!
Yeah, no this is good info too. I havent really been able to come back to this thread until today. So many different considerations and right now I'm only running Eibach springs today with really no other suspension mods today. Im also not on Magnaride either.

What I think I'm going to actually do is just run the 19/10 on the 275/35/19 RT660 tires.

Few reasons I'm thinking this...

  1. This will be my only second year running this specific car for HPDE
  2. (and this is a BIG if) I may end up trying to get into a GT350 end of next year or maybe the following
  3. I'm not sure I want/NEED to spend the extra money and time to go with 19/11 right now


With me just getting back into road racing and HPDEs I think the right thing probably is to get more familiar with the car and up my skills more. I know going 19/11 will def give me more grip and give me a better time, but right now I'm just not sure it makes sense for me....
 

MarquanTR

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Yeah, no this is good info too. I havent really been able to come back to this thread until today. So many different considerations and right now I'm only running Eibach springs today with really no other suspension mods today. Im also no on Magnaride either.

What I think I'm going to actually do is just run the 19/10 on the 275/35/19 RT660 tires.

Few reasons I'm thinking this...

  1. This will be my only second year running this specific car for HPDE
  2. (and this is a BIG if) I may end up trying to get into a GT350 end of next year or maybe the following
  3. I'm not sure I want/NEED to spend the extra money and time to go with 19/11 right now


With me just getting back into road racing and HPDEs I think the right thing probably is to get more familiar with the car and up my skills more. I know going 19/11 will def give me more grip and give me a better time, but right now I'm just not sure it makes sense for me....
If you end up with a gt350, 19 x 11 ET 52 wheels will fit both your current car(with extended studs + 25mm spacer) and the gt350. That’s also something to think about because I think 10” wide wheels won’t fit the gt350 due to the breaks but I may be wrong. But do what fits your needs and goals above all, there’s tons of options out there
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