200tw tires for Track use

[krs]

It’s just the opposite of a stretch, a tire that is slightly wider than optimum for the wheel width.
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It works in AutoX because you typically will run the tire at maybe 38-42psi cold, whereas at the track I run about 33 cold, in order to accommodate for the extra heat that builds up. Higher PSI effectively results in more sidewall support. With the higher PSI in AutoX the tire will be less susceptible to deflection under load (ie turning), hence why you can get away with a more pinched tire.

Ah, that makes sense now. I figured it was a reference to wider than stretched, just hadn’t heard that term. Thanks for clarifying.

 

[DerHase]

While I've not driven on all of the tires on a GTI, I've run through several sets of different things on my Mazda2 which was my previous track car (and was autocrossed a lot prior to discovering track things).

Bridgestone RE71R (I burned through 2 sets) - Awesome grip for a lap or two, then get greasy. Great for autocross, great for time trial track stuff... not great for doing repeated lapping. Also sucked because they wear stupid fast. They have a very "sharp" feel where you can tell they're breaking traction laterally. Definitely rewards smooth driving generally speaking. Funny enough I found it more cost effective to run a set for about half their useable life, sell for 50% of the original purchase price to someone, and buy another set. When I was autocrossing it literally cost me the same to buy two sets for a season and always be on "fresh" tires than try and stretch a set of one all year (which was definitely doable with regular rotations and flipping on the rim). Awesome in the rain as long as it wasn't deep standing water. One of my sets I used for autocross, it was on these tires I did my first HPDE weekends and then proceeded to burn the second set up doing the same.

Hankook RS4 (3 sets) - Wears like iron and lasts easily 3-4x as long as RE71Rs. Terrible for autocross unless it's stupidly hot out AND you had a codriver. They're still not the fastest but they're not as bad relatively speaking. Back to TRACK things: they were maybe 0.5-1.0sec slower on a 90 sec road course vs RE71Rs, BUT they could do those laps repeatedly ALL session long never falling off. The RE71R would have a flyer lap and then slow down to roughly the same overall speed. These tires feel like crap unless you have them stretched on the wheel. Also these things run WIDE. I ran 195s(which actually measured WIDER than 205 RE71Rs) on 8in wide wheels, and 225s on 9in wide wheels. If you can make them work, or don't care about the "fastest" time possible, these things are a great tire if you're on a budget, or drive on an abrasive surface, or have a lack of camber with no desire to add more. Really sucks in the rain, but nowhere near as bad as BFG Rivals. Predictable breakaway, just low limits in the rain.

Falken RT660 (2 sets) - Very similar overall feel to RE71R. Within noise of the RE71R time wise overall (comparing a flyer lap from RE71R only), but does not get greasy anywhere near as quick. Typically good up until tail end of a 20 min session. Wears somewhere between the RS4 and RE71R. Not quite as good as the RE71R in rain, but also not as bad as the RS4. Honestly I really like these as a happy medium for doing everything well enough. I bought a set of 245/40R17s for my GTI and had no complains of them at VIR a few weeks ago.

No comment on anything else, though I've driven a bunch of other tires just on different cars and/or not for enough laps to make a fair judgement call.

edit: I will add that because my car only made 97 wheel horsepower… Forward traction was not exactly something ever really being tested to the limits except in the rain. The RS4s were probably worst of the bunch in that circumstance though. I also just remembered that the RS4s I ran were 195/50R15 vs 205s for everything else. In ACTUAL size comparisons the 195s were a tiny bit wider than 205 RE71Rs, and 0.6in shorter overall. I suspect gearing came into play and if all sizes were truly equal, the delta between them and the others would be a bit larger.

 

[GTIfan99]

What do you mean by pinch? I understand the stretch term…

Stretch is when wheel is a little wider than tire, square is tire and wheel same width, pinch is tire wide that wheel.

Square is optimal, but often in autocross you have rim width or tire width restrictions. A little pinch for extra tire is fine in autocross, the increase in lateral grip is usually worth the slightly less than optimal feel.

 

[bfury5]

Pinch is fine if you're limited by class rules, but you usually trade increased grip for decreased tire life. Also very tire dependent. My car in STH trim loved a 245 on a 9" wheel. I stepped up to 255 and I'm not convinced it was actually faster due to being a little sloppier

 

[GTIfan99]

Pinch is fine if you're limited by class rules, but you usually trade increased grip for decreased tire life. Also very tire dependent. My car in STH trim loved a 245 on a 9" wheel. I stepped up to 255 and I'm not convinced it was actually faster due to being a little sloppier

Agreed, it's trial and error and often your end to with a shorter or taller diameter than you wanted.

I'm thinking about 245 40 17 RT660 next time. They run as wide as other 255's and the sidewall will be shorter, a plus in a manual mk7.

 

[bfury5]

Agreed, it's trial and error and often your end to with a shorter or taller diameter than you wanted.

I'm thinking about 245 40 17 RT660 next time. They run as wide as other 255's and the sidewall will be shorter, a plus in a manual mk7.

Yeah I liked the shorter 245/40 as well for the manual. 2nd is already so long, smaller diameter helps a bit

 

[DerHase]

They are definitely not stretched by any means even on a 9in wheel. They took a moderate amount of fighting to push the upper bead below the bead seat.

(245/40R17 Falken RT660 on 17x9 Apex SM10)

They all took like 60psi to fully seat as well.

 

[SouthFL_Mk7.5]

Just threw my money at a set of 660’s to replace the set of well worn RT615K. Gonna get them mounted this week and will try them out Sunday autox.

 

[jmblur]

Y'all are making me consider selling my RS4s and getting some 660s... On a car I might not be autocrossing beyond this year. Stop it!

 

[Mini7]

The stretch conversation for the track is making me think I should pass on trying to squeeze a 265-35-18 under my fenders on my 18x9 SM-10’s.

245-40-18 is a little tall and I had some fender liner rubbing with these.

 

[GTIfan99]

The stretch conversation for the track is making me think I should pass on trying to squeeze a 265-35-18 under my fenders on my 18x9 SM-10’s.

245-40-18 is a little tall and I had some fender liner rubbing with these.

265 is always the answer. Lol.

But seriously, 245 width RT660's are close to what everyone else calls a 265. No joke.

 

[SouthFL_Mk7.5]

Just threw my money at a set of 660’s to replace the set of well worn RT615K. Gonna get them mounted this week and will try them out Sunday autox.

Just picked them up.
225/45 on a 17x7.5 Assetto Gara

 

[Autobahn]

The stretch conversation for the track is making me think I should pass on trying to squeeze a 265-35-18 under my fenders on my 18x9 SM-10’s.

245-40-18 is a little tall and I had some fender liner rubbing with these.

255/35/18 on a 9” wheel seems to be the sweet spot IMO, 25” tall which leaves good fender liner clearance when running additional caster up front. The section width is normally around 10 - 10.4” depending on tire.

I have some Cup 2’s 245/40/18 (25.7” height) and they were rubbing my fender liners on very hard compression. It seems most 245’s run very tall making you have to run your car a tad higher than with the 255’s especially with extra front caster.

I’m trying out the V730’s in a 255/35/18 coming from the RE71R which has the same specs for the first time in a few weeks at Auto Club Speedway. Should be a good test, weather should be in the low 80’s unless I get lucky with cooler weather.

 

[Mini7]

I’d agree. 25” diameter is ideal which makes the 255-35-18 a good choice.
25.3/25.4” is about the limit before running in clearance issues like you say. My car has minimal drop in ride height. I’m not concerned about front clearance with a 265-35. Just the right rear.

The V730’s have a great price point compared to other tires and they appear to be a good all round tire.

 

[Bernb6]

RT660 245/40/18s are unusable on my GTI. I've run this size in Nitto NT-01 and Hankook RS4 with no problem. But the RT660s wore through a fender liner in about 20 miles. My shop will be putting RS4s on next week. Anyone want a set of near new RT660s?
Bern