All gen 1 R8s left the factory with 235/35-19 on the front. Some had 295/30-19 and others had 305/30-19 on the rear depending on which wheel option was chosen. So your 305 & 235 combination is a legitimate factory configuration. I can understand why you wouldn't want to deviate too far from factory spec - I'm assuming it would cause unnecessary wear & tear or heating of the viscous coupling. It would be good to hear from @Ricky.REP though if he's encountered any problems with the 305 / 235 combination. My previous V8 came with that combination from the factory and I had no issues, although I sold it with less than 15,000 miles on the clock, so maybe not the best reference for any potential long term damage!

 

Thanks for your comments @steve9. Deviating doesn't concern me too much, it's really Ricky's wealth of knowledge and general reputation around R8's makes me ask why is that combination recommended and the "DO NOT MIX" comment when it's literally factory spec.. the pros/the cons etc.. etc.. I didn't fail to notice the comment of availability with Cup 2's either but is that the only reason?

For anyone not familiar, the below is a link to the point that I'm talking about Ricky calling out not mixing, despite R8's leaving the factory with the configuration. Link skips to the right section and needs about 30 seconds of your time.

 

Well, Ricky would be the last person I would argue with about R8 matters, but his comments imply that the some R8s left the factory with 245 on the front and 305 on the rear, depending on year. That's not the case - all gen1 had 235 fitted and 305s have been an option at least as far back as 2009, including the V8. Even the 570 hp LMX right at the end of the gen1 series had 235s. It might be worth calling him though to see if he's observed any issues; I don't recall any reported on the forum.

Admittedly, I always found it very strange that two mechanically identical cars left the factory with different width, therefore different diameter rear tyres, especially on a 4wd format.

 

Absolutely, it makes little sense to me either and I'm not concerned about about sticking with what I have. I'd just like to know the reason he said not to mix with the exact tyre sizes It sounds like my car left the factory with.

I was going to comment that I'm surprised it hasn't been more of a discussion point, after all, this isn't a modification, everyone needs tyres and the "Guru" himself is saying not to mix but maybe the video is just a little late for Gen 1 discussions and Gen 2 focus has taken over.

Thanks for your comments and opinions anyway.

 

This might make it clearer

2008 Audi R8 - Wheel & Tire Sizes, PCD, Offset and Rims specs | Wheel-Size.com

 

@DaveL Apologies, am I missing something? The website states 245/35/19 fit on the front, which we know from what Ricky said in his video, but he also stated "Do not mix 235/35/19 and 305/30/19, yet my car seemingly came from the factory with that spec....

 

245/35ZR19 95Y 305/30ZR19 101Y

8.5JJx19 ET42 11JJx19 ET50

2.7 2.9

Shown for the V10, so I think we´re all missing something! Check your rim widths, that should be the deciding factor..

 

I'll double check them but notice regardless of 235 or 245, it still saids 8.5JJ

 

I don't think all gen 1 came with 235 front. I think since the introduction of the V10 and spider and depending on wheel choice some may have had 245 and were paired with 305 but I'm not certain. However, funnily enough I just watched that vid myself a few days ago and noted that comment, but I'm pretty sure when I actually spoke to Ricky when I took my car in and I asked him about that very subject I'm sure he said that any combination of factory sizes was ok. I currently have 235/305 on mine and no issues but in hindsight wish I'd gone 245 up front just for that extra bit of width and rim protection. Next set of tyres I will.
235/295 = roughly 1.9% difference off the top of my head
235/305 = roughly 2.9% difference off the top of my head. General consensus on here if I recall correctly seems to be that under 3% is ok. Possibly to to 5%.

 

Thanks @stug360, my last response was in response to @DaveL. I appreciate your thoughts and it's not so much that I'm trying to get some benefit out of 245's or really want 245's over 235's rather, I have already have 305's on the back, I have no intention of changing that sizing, but for most owners, I see they consider Ricky has knowing his stuff and yet he's commented pretty boldly not to mix 235 with 305.

It could have been a mistake, it might mean nothing at all, I've little concern of fitting the same again that I already have "235 with 305", but for most I'm sure you want things to be right on this type of car and in theory, you don't get more right than the dealer spec but It just bothers me not knowing..

... Either your a Price Ascending sort of purchaser or you're a review to death and understand every aspect before its even arrived sort of purchaser - I'm the latter.

 

My rim is definitely 8.5 inches which according to below site chart means 235 or 245 can fit if the tyre profile is 30, 35 or 40mm. Doesn't answer why Ricky said don't mix 305 Rear and 235's Front though and either no one noticed, people followed his advice blindly or most aren't "Hands on", take their car to a garage and say "fit tyres". Not trying to offend anyone, he just made a very bold statement of "Don't Mix"??

tire-width-for-a-wheel-rim-size-chart

 

I wonder if Rickys statement was aimed more at handling/understeer rather than any mechanical risk. Having a wider rear with the smaller front might create a little more understeer, hence better to increase the front along with the rear to keep the handling characteristic. Another reason why next time I'll move up to 245.

 

My 2014 V10 Spyder, came with 235 front, 305 rear, it's on the 'snowflake' pattern wheels as it came from the factory.
Personally, I will stick to this spec, unless I change to different wheel sizes, diameter, width, offset etc:

 

If you do the math, there is a 3mm wall height difference between 305 and 295 and a 3.5mm difference between 235 and 245. Worst mix scenario 6mm in wall height difference, add in wall flex, it's not even a decent bump in the road.

 

Fair enough... it makes so little difference, Ricky's opinion is his opinion but from what you are saying, you could in theory run any combination 295 with 245, 295 with 235, 305 with 245 or 305 with 235 and never notice any difference at all in drivability, grip etc.

 

The way I see this is any of the afore mentioned tyre size combinations are not going to be in any way detrimental to the car's awd system, and the fact that Audi offered them as options reinforces this.

When it comes to on-limit handling, however, some combinations are likely to work better than others. For example, increasing front grip can induce oversteer, while increasing rear grip can result in more understeer. To overcome this, size combinations of either 235/295 or 245/305 are likely to provide the best results in terms of a more balanced setup.

 

Got it. It does further validate @stug360 assumptions on It being to do with handling characteristics and presumably Ricky's experience is that it's better to run 245/305 or 235/295 as part of a "balanced" setup rather than inducing oversteer/understeer.

YouTube and the wealth of knowledge it provides is unquestionable but there are times like these that do cause frustration when comments can be boldly made with little thought and yes I can call Ricky and ask him but he's trying to run a business, he's not there to answer questions all day but I do want him to do some work in the near-future so I have every intention of raising the question then - I just need tyres now, by the time I found out "why" he said it, it will be too late for this round.

 

@stug360, yup, 245's certainly more where I have always brought tyres. Camskill encase you were wondering - usually the best prices around, at least in the UK. My bill for a set of PS4S was £1034 exactly for 245+305's including shipping.

I'm still none the wiser of the 245 benefits other than it definitely sounds plausible it adds stability when the rear's 305 so it's a finger in the air YOLO sort of decision.

Thanks for your inputs on the topic!

 

I think all Gen1 came with 235 fronts on R19. None, ever, with 245. Can anyone with a Gen1 post a door sill with 245 printed on the wheel/tire pressure label?

 

Thanks. Referring to my original post though.

It was the fact that Ricky from RE Performance had mentioned 245 with 305 or 235 with 295 and not to mix that I was querying.

I believe all R8's came with 235 at the front and either 295 or 305 at the back as you say... though you make a good point. I'll have to check my door sill.

 

My door sticker gives pressures for 235 with both 295 and 305 at the rear so I would infer from that that mixing 235 with either rear option is perfectly ok.

 

I found some references to 245/305 it being an official Audi setup in the US on a package option called “Titanium Package” so there you have it. It appears official, tyre setup isn’t mentioned but Audi are confirming its a real package, just finding the brochure option now.

 

2012 Audi R8 Coupe Specs & Trims

Latest technology in the 2012 Audi R8 Coupe: Compare all specifications and configurations of the 2012 Audi R8 Coupe, special features and options, and check out specs and trims on CarBuzz

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Titanium pkg
$6,500
black optic pkg exterior, black fine nappa leather seats, Piano Black interior inlays, black leather door inserts, black leather interior door handles, black alcantara headliner, titanium finish 19" 5-arm double-spoke wheels, black exhaust pipes, summer performance tires (N/A w/5MN Carbon Fiber Sigma Interior Inlays)

 

245 were not in the titanium pack. Only the 305 on the rear was included. At the time, the Pirelli PZero which was OEM fitment back then, was never homogated for the R8 in 245/35-19. No R8s left the factory with 245 until the release of the gen2.

 

Here's an old USA price list. you can see the titanium pack includes the titanium wheels, and further down note the titanium wheels are fitted with 235 / 305

 

Thanks @steve9 You are not wrong, I see it said's 235's on the brochure. I finally found where I saw a reference to it and it was Audi Canada that Titanium Package was mentioned as coming with 245's but the could have been mistaken... but regardless, alas a conversation about guys from this forum putting 245's on the front.

With 305 rears, use 235 or 245 on the front?

For a street / track setup (street tires), would you suggest OE 235/35 19 or 245/35 19? With the slightly larger diameter 305s on the rear and the car's natural understeer it seems that the 245s would be preferable.

www.r8talk.com

 

for anyone that's wondering.. I've been running 245/35/19 on the Rear, 305/30/19 on the Front without any issue since March - no rubbing etc.

The car came with Pirelli's and I was keen to move to PS4S's so though I can confirm the car seems to handle even better than before, it might simply be the result of PS4S tyres over Pirelli's.

As to whether the size makes a difference, that's unknown from my perspective but more tyre touching the road can only be a good thing I would have thought but ultimately unless tracking (as others have alluded to), go for good quality tyres for the best price, whether that's
F:235 - R:295 or F:245 - R:305

---

Back to my original questions of whether it's best to stick to purely the above sizes, I still don't have the answer...

All I can affirm is that my car came with F: 235/R: 305, I'm now running F:245/R:305 PS4S's and it feels even better turn in, sharper somehow. As above whether than the tyre make or sizes or even both - no idea.

Does it matter whether you run F: 235/R:305 or F:245/R:295 which Ricky said not TO, again - unknown.