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R888 Tyre Size Vs Rim Size

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ISC-Performance Veteran

ISC-Performance

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Currently have 235/40/18 all round, running 8.5" wide front and 9.5" wide rear. Looking at getting some more grip down and was thinking of putting 255/35/18 on the front but was seeing if anyone else had done this using the same rim width and if there was any bulge creating more of a disadvantage then an advantage etc? If I can run the 255 on the front I'll go 275/35/18 on the rear. If not I'll just stick with the 235/40/18 on the front and upgrade the rear to 255/35/18.

Any opinion/experiences would be appreciated!

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No Crust Racing Grand Master

No Crust Racing

Posted
Posted

Hey Ryan,

Check this

http://www.toyor888.net/racing/index.htm

8.5inch is the smallest recommended for a 255 and you might find it moves around a touch which will result in quicker warm up temps and possibly higher peak temps.

This is just my understanding though, some of the gurus will likely drop in and correct me.

ISC-Performance Veteran

ISC-Performance

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Yeah checked that link, 8.5"-10". Hmmm quicker warm up would be good as the car is time attack not circuit so only 3/4 of a lap then into one timed lap straight away. Just don't want the front to feel squirmy and un predictable.

No Crust Racing Grand Master

No Crust Racing

Posted
Posted

It's hard to say how it will respond as each R compound has slightly different widths for a given tyre size. Obviously the best way is to test but then you've forked out the bucks already.

As an aside, When looking at the R888s I was advised slightly away from them by some other circuit guys on here stating that they are in the same ball park grip wise as a KU36, which isn't even an proper Semi.

Can you use your contacts to get some cheap AO50s or RE55s? What are you currently using?

I'm in the process of shopping myself and might just grab another set of second hand RE55s as mine have been good.

ISC-Performance Veteran

ISC-Performance

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yeah using R888 now and rate them pretty highly.....not saying there the best semi out there and I'am definetly open to trying other brands etc. Have also tried KU36 and didn't rate them to well, took a long time to come up to temp (not ideal for time attack) BUT the KU36 are def good value for $$.

No Crust Racing Grand Master

No Crust Racing

Posted
Posted (edited)

Ahh OK well if you're already on them and are comfortable then all good.

Anyone you know running the same sizes you want that you could borrow from? Chuck on their wheels and go?

Is this on an S chassis?

Edited by ActionDan
ISC-Performance Veteran

ISC-Performance

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Ahh OK well if you're already on them and are comfortable then all good.

Anyone you know running the same sizes you want that you could borrow from? Chuck on their wheels and go?

Is this on an S chassis?

unfortunately not :-(

Beer Baron Grand Master

Beer Baron

Posted
Posted

I wouldn't run 255 semis on a 8.5. 235 is ideal. you could probably get away with 245 if you want though.

I would buy a pair of 255s. try them on the front rims. see what you think. if you don't like it, put them on the rear 9 inch rims, and then buy 235 or 245 for the fronts.

R31Nismoid Grand Master

R31Nismoid

Posted
Posted

I think you'll get more out of a better tyre @ the same sizes as it doesn't seem the R888 is much chop compared to other choices around, which is probably more important for Time Attack in terms of grip rather than a club sprint type/general track day where you are cutting many laps/sessions

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