[Baldnut]

Hi I have looked all over and can't find info on this.

I have put Michelin Pilot Sport 4S tyres on my redeye with 315x35x20 on rear and 305x35x20 on the front. Perfect fit with no rubbing.

I had previously had the Pirelli All Seasons on it and the handling was great, but with the Michelin it seems as if its got excessive movement when you floor it as if the sidewalls are flexing. I have the tyre pressure at 35PSI (what I used to run on the Pirelli P-Zero's) and the tyre says "Max pressure 50PSI" I cant imagine it would be sensible to put 50 PSI in, I just wondered if anyone had any experience with this tyre and had a recommended PSI for them as currently the car feels unstable when I put it under pressure.

 

[16GoManGoHC]

Sorry can’t help on that question but question for you, How are these gripping from a dig for you? Wide body or normal body? I’ve been contemplating trying a set on the rear as one member has said they grip better then the Nitto DR’s from a dig. Any input on that? What’s your RWHP appx?

 

[DGatzby]

Take them down a bit to 32 psi. I run my 345 rears at 29-30 and front 325’s at 32 (cold) stable as it can be with this much power.

 

[16GoManGoHC]

Take them down a bit to 32 psi. I run my 345 rears at 29-30 and front 325’s at 32 (cold) stable as it can be with this much power.

How do these hook for you from a dig? You ever run a Nitto DR and have any comparison opinion between the 2? Over winter Time for a new set of rear skins, I could never fit 345’s unfortunately but wondering if the PS4S or anything hooks better from a dig then the Nitto 315 NT05R or 555R2? 315 is as big as I can fit.

 

[DGatzby]

How do these hook for you from a dig? You ever run a Nitto DR and have any comparison opinion between the 2? Over winter Time for a new set of rear skins, I could never fit 345’s unfortunately but wondering if the PS4S or anything hooks better from a dig then the Nitto 315 NT05R or 555R2? 315 is as big as I can fit.

I say about the same on a street anyway. I have used all three. The one thing I noticed about this THIRD year of service the 345’s gave me is that I cannot get the 3.3-3.4 second 0-60 like I could when they were new. The car recorded it best forward G-force not long after they were new and has not bettered it yet. It is not way off, but it won’t get better than a 3.6 and that must be on some concrete. Probably the same can be said for a few year old drag radial or “R” type, but they never last that long. These wear great and have a respectable amount of thread remaining, but are not as “sticky” as when they were new.

 

[16GoManGoHC]

I say about the same on a street anyway. I have used all three. The one thing I noticed about this THIRD year of service the 345’s gave me is that I cannot get the 3.3-3.4 second 0-60 like I could when they were new. The car recorded it best forward G-force not long after they were new and has not bettered it yet. It is not way off, but it won’t get better than a 3.6 and that must be on some concrete. Probably the same can be said for a few year old drag radial or “R” type, but they never last that long. These wear great and have a respectable amount of thread remaining, but are not as “sticky” as when they were new.

Well the Nitto’s make about 3-4000 miles and their done (all be it they do see hard service) If from a dig traction is about the same with the PS4S but live twice as long that would be a plus. I may have to try a pair for next spring. THANKS for the reply!!

 

[16GoManGoHC]

I say about the same on a street anyway. I have used all three. The one thing I noticed about this THIRD year of service the 345’s gave me is that I cannot get the 3.3-3.4 second 0-60 like I could when they were new. The car recorded it best forward G-force not long after they were new and has not bettered it yet. It is not way off, but it won’t get better than a 3.6 and that must be on some concrete. Probably the same can be said for a few year old drag radial or “R” type, but they never last that long. These wear great and have a respectable amount of thread remaining, but are not as “sticky” as when they were new.

What you seeing for forward G force on the street from the car timer with those tires new to worn? I see in the mid .9’s on warm pavement, mid 8’s now cold street and at the wear bars, and when I get the clutch throttle combo just right 1.15. I’ve seen 1.6 at the track with them with a little heat put too them.

 

[DevilsReject97]

PS4S should always be run at 32 cold, and they'll get to about 35-36 hot easy... for daily use

Storage should always be 45-48 PSI ballpark.

 

[DGatzby]

What you seeing for forward G force on the street from the car timer with those tires new to worn? I see in the mid .9’s on warm pavement, mid 8’s now cold street and at the wear bars, and when I get the clutch throttle combo just right 1.15. I’ve seen 1.6 at the track with them with a little heat put too them.

She put down 1.16 on a pretty good street, me and another guy riding. Been trying to get it better ever since! The Cup 2’s can’t do better even when hot. They don’t like the DIG deal as much as laterally holding on.

 

[16GoManGoHC]

She put down 1.16 on a pretty good street, me and another guy riding. Been trying to get it better ever since! The Cup 2’s can’t do better even when hot. They don’t like the DIG deal as much as laterally holding on.

So this is the PS4S better from a dig?

 

[Baldnut]

Sorry can’t help on that question but question for you, How are these gripping from a dig for you? Wide body or normal body? I’ve been contemplating trying a set on the rear as one member has said they grip better then the Nitto DR’s from a dig. Any input on that? What’s your RWHP appx?

I think by dig you mean Launch? Sorry im from uk and have not heard that term before. They do launch well with good traction but the car feels like its all over and it never used to on the Pirellis. I think dropping the pressure sounds a better idea than increasing it. The only reason I thought put it up rather than down is the car usually showing tyre pressure as too low when its like 32/33 etc (from dash info)

Yes it is widebody.

Many thanks

 

[Baldnut]

Take them down a bit to 32 psi. I run my 345 rears at 29-30 and front 325’s at 32 (cold) stable as it can be with this much power.

Do the 345's not rub or have you done mods? I am guessing your not on a standard Devils Rim either?

 

[Xylander]

Did you oversize the rubber for the wheel? Wandering at launch is often caused by "skating." The tire's contact patch is directly related to the wheel width. The stock 11" wheel caps out at 305. So, putting 315s on a stock rim = just 305s on the pavement. That added width gets rolled up in the sidewalls. The direct result is the car will skate left-to-right as the contact patch shifts under load. If you're not on stock rims, disregard.

To fix it, either reduce tire size to 305 or add 11.5" wheels.

 

[DGatzby]

Do the 345's not rub or have you done mods? I am guessing your not on a standard Devils Rim either?

Widebody, 12” wide wheel. No rubbing. Have two sets 12” wide wheels. A Cup 2 and the PS4S don’t rub in that size.

 

[Baldnut]

Did you oversize the rubber for the wheel? Wandering at launch is often caused by "skating." The tire's contact patch is directly related to the wheel width. The stock 11" wheel caps out at 305. So, putting 315s on a stock rim = just 305s on the pavement. That added width gets rolled up in the sidewalls. The direct result is the car will skate left-to-right as the contact patch shifts under load. If you're not on stock rims, disregard.

To fix it, either reduce tire size to 305 or add 11.5" wheels.

Makes a lot of sense, yes this is stock 11" rims. I will fry the tyres and stick to the 305's thank you

 

[Xylander]

In addition, the reason why some people don't get that skating effect has to do with what tire they're using. Nitto, for example, have fairly rigid sidewalls, where the PS4S is a very flexible tire. Both tires skate when oversized, but you feel it more on the PS4S because the sidewall is flexing (which, when optimal, is what you want as it allows for greater traction bite). That skating, however, is taking all that extra traction bite and transferring it into lateral motion instead of increased grip. Hence the wonky feel.

 

[Baldnut]

In addition, the reason why some people don't get that skating effect has to do with what tire they're using. Nitto, for example, have fairly rigid sidewalls, where the PS4S is a very flexible tire. Both tires skate when oversized, but you feel it more on the PS4S because the sidewall is flexing (which, when optimal, is what you want as it allows for greater traction bite). That skating, however, is taking all that extra traction bite and transferring it into lateral motion instead of increased grip. Hence the wonky feel.

Sounds like you hit the nail on the head. Will take it easy on them until I can get them changed back to 305's. I could swap around and put the 305's on the rear and try what they are like but that would mean putting the 315's on the front and they may rub or cause more driving issues being on the front rather than the back.

Many thanks for the advice.

 

[Himmelkat]

I have run tires at max allowable pressure for years. If my truck tire said 80 PSI, I ran it at 80. The tire lasted very long as a direct result
I ran my Hellcat tires at 50 for a long time. I'm not sure why you would think running a tire at its max pressure would be dangerous. If it was dangerous, it would not say 50 PSI.

Try putting 50 in them and see how they act.

 

[Baldnut]

I have run tires at max allowable pressure for years. If my truck tire said 80 PSI, I ran it at 80. The tire lasted very long as a direct result
I ran my Hellcat tires at 50 for a long time. I'm not sure why you would think running a tire at its max pressure would be dangerous. If it was dangerous, it would not say 50 PSI.

Try putting 50 in them and see how they act.

Sure its certainly worth a try to see how it drives. It doesn't feel right now so nothing lost by pushing up the pressure. Will let you all know. But I still think it is wise to go back to the correct width tyre once I come to replace them.

 

[Himmelkat]

Also, my wear was close to even on middle and both sides. There was more variation left-to-right than there was either side-to-middle. (Camber and all, from the factory.)