[iownedu]

Looking for some input, I'm experiencing alot of wheel spin in 2nd gear, and some in 3rd as well on map 2 (93 octane, ~1100whp) now that the current rear 19" Toyo R888R's are getting down to their last 1/3 of tread above the wear indicators.

Spinning in 2nd gear was hit or miss when the tires were new, 3rd gear use to hold. Tires have never been below freezing or anything, properly taken care of. It is possible I could be experiencing some bead slip between the tire amd wheel, have not marked to test this however. My current 19" ADV1 wheels do not have the bead seat knurled.

I'm changing to a custom 18" beadlock setup on all 4 corners, and may just run a higher race gas map all the time as I don't drive it alot. Considering running this tire setup:

Front
Toyo R888R 245/40ZR18
25.7" OD, 9.8" width
808 revs/mile

Rear
Toyo RR 305/35ZR18
26.4" OD, 12.3" width
786 revs/mile

Do you guys have any experience with the Toyo RR out back? Better straight line traction on the street? They have a treadwear rating of 40 versus the 100 rating on an R888R so I'm quesstimating real world life of 2400-3200 miles, anybody tested this?

These will be used in Vegas where there is alot of greasy black top asphalt, obviously rain is not a concern.

 

[Plumber]

I’m not running as much power as you and I had 325/19 R888R on my rear. They were old so I replaced with 325/19 Sport Cup 2 (R888R were on indefinite back order in that size). With both sets of tires I get wheel slip in first and second when under full power. Not much but there is some, even when warm. 305 might be a bit narrow for your power setup.

 

[iownedu]

I’m not running as much power as you and I had 325/19 R888R on my rear. They were old so I replaced with 325/19 Sport Cup 2 (R888R were on indefinite back order in that size). With both sets of tires I get wheel slip in first and second when under full power. Not much but there is some, even when warm. 305 might be a bit narrow for your power setup.

That's a good thought, I can't get 325 in 18" though. I can get 315\30ZR18, however they are 25.5" OD, so slightly smaller than my front tire which may look weird.

 

[Plumber]

235/35/19 front
325/30/19 rear

 

[Plumber]

And when warm the sport cup 2 handling is sublime. I really don’t feel like I can reach the cornering and grip limits on the street with this setup. The car is planted. Haven’t taken it to the track though.

 

[iownedu]

235/35/19 front
325/30/19 rear

View attachment 296428

How long have you been running this size pairing? They are a pretty significantly different OD.

Specs for R888R.

235/35R19
25.5" OD
816 revs/mile

325/30R19
26.7" OD
777 revs/mile

 

[Plumber]

This is at least the second set of tires
39 revs / mile. Is that much different than what you’d get from cornering etc? IDK

 

[iownedu]

This is at least the second set of tires
39 revs / mile. Is that much different than what you’d get from cornering etc? IDK

I'm not really sure where the line is that damage can occur, seeing you out that much without issue is great!

 

[cousinducky]

I’m not running as much power as you and I had 325/19 R888R on my rear. They were old so I replaced with 325/19 Sport Cup 2 (R888R were on indefinite back order in that size). With both sets of tires I get wheel slip in first and second when under full power. Not much but there is some, even when warm. 305 might be a bit narrow for your power setup.

Apparently you can get the 325/19 R888R now, seen it online in a few places. I'm running 305 R888R now...

what's the advantages of going to a 325 over a 305? I'm surprised they fit.

Was it that big of a difference with the added size of the 325?

 

[Plumber]

Apparently you can get the 325/19 R888R now, seen it online in a few places. I'm running 305 R888R now...

what's the advantages of going to a 325 over a 305? I'm surprised they fit.

Was it that big of a difference with the added size of the 325?

I have nothing to compare since that’s how the car came — Velo wheels with 325 rears. Not sure of wheel width or offset but they fit nice. 20mm is almost an inch wider per tire. That’s a big difference but for daily use I have no idea if you’d notice.

 

[Cliff.1620]

You guys inspire me! I just want to TT my SL!

 

[iownedu]

Apparently you can get the 325/19 R888R now, seen it online in a few places. I'm running 305 R888R now...

what's the advantages of going to a 325 over a 305? I'm surprised they fit.

Was it that big of a difference with the added size of the 325?

As Plumber stated it will be 20mm wider, but also 30% of 20mm taller sidewall (6mm). Toyo has all the specs of OD, revs/mile, width etc on their website which is extremely handy.

In your case, since you have the 305/30ZR19, you could measure physically on your car. If you have over 10mm clearance on both the inner and outer edge, and over 6mm clearance from top of tread to fender lip, then you can fit the 325/30ZR19.

 

[CFI Designs]

with 12-1300 on a RWD setup we dont have issues running a r888 on a 19".

 

[iownedu]

You guys inspire me! I just want to TT my SL!

Do it, you won't regret it at all! Or find a good one to buy to replace your current car if that makes more sense.

 

[iownedu]

with 12-1300 on a RWD setup we dont have issues running a r888 on a 19".

I'm assuming heavily leaning on boost by gear and only making 6-800 whp in 1st-3rd though?

I'm looking to hold upwards of 1400whp in 3rd and up, maybe close to 1000whp in 2nd.

 

[CFI Designs]

I'm assuming heavily leaning on boost by gear and only making 6-800 whp in 1st-3rd though?

I'm looking to hold upwards of 1400whp in 3rd and up, maybe close to 1000whp in 2nd.

yes boost by gear and a drop gear ratio change so the gears are longer as well...never really try and take off with these cars from first.

 

[cousinducky]

As Plumber stated it will be 20mm wider, but also 30% of 20mm taller sidewall (6mm). Toyo has all the specs of OD, revs/mile, width etc on their website which is extremely handy.

In your case, since you have the 305/30ZR19, you could measure physically on your car. If you have over 10mm clearance on both the inner and outer edge, and over 6mm clearance from top of tread to fender lip, then you can fit the 325/30ZR19.

Thanks.. I just wonder if there's any real traction advantage over what I have now? hmmm... probably not much or anything noticeable beyond the placebo effect.

 

[LamboTT]

How long have you been running this size pairing? They are a pretty significantly different OD.

Specs for R888R.

235/35R19
25.5" OD
816 revs/mile

325/30R19
26.7" OD
777 revs/mile

run whatever large tire in the rear that will fit as long as you use a 235/35/19 up front.

Everyone in the world use to think the 305/30/19 was all you could run in the rear with a normal 235/35/19 up front, literally no one ever tried anything larger I could find. Well somewhere around 7-9 years ago, I ran a 235/35/19 and a 345/30/19 with out any issues for a while. It simply locks of the vicious coupler up front faster but nothing that was bad.

 

[Plumber]

You guys inspire me! I just want to TT my SL!

If you can swing the $$$ (or £ haha) it is an upgrade that brings the power up to the level of what I believe the chassis is truly designed for. And now the speed matches the looks 😉

 

[RMR]

And don't forget to upgrade the brakes! I have next gen carbon ceramic rotor fitments for cars equipped with the base, 8-piston iron brakes as well as cars with CCB brakes. Half the cost of OEM and superior in every single measurable performance parameter. Game changing.
New carbon ceramic brake option for the Gallardo!