Twice now I have been to the strip only to experience a two tenths loss in et. At 60 ft I am 1.81 to 1.85 vs. 1.75s before, At 330 I am 5.2 or 5.3 vs. 5.1, At 1/8th 8.0 vs 7.8, At 1000ft 10.3 to 10.4 vs 10.2s, Quarter mile 12.34 and 12.39 vs. 12.15 to 12.17. The rear P2 275 is 26lbs vs 25lbs and 25.6 tall vs 25.2 tall on the Cont's. Front tire is 25lbs vs. 24 on tire rack specs, Mich v Cont. Rides great but my et sucks. Tried different pressures w/o change. Conts always had 35lbs air pressure. With traction control off I have marked up the streets around my house with P2s. Cont marks faded fast P2S repave the road with dark marks that fade slowly. Obvoiusly Mich is harder compound and .4 difference in height killed some gear ratio.

 

Dude, you're complaining that your E55 does low 12s???

 

PS2's rock. Stickier tire than the stock Conti's.

 

Hmmm....are we comparing apples to apples? Same track, same pavement conditions, same weather conditions, etc?

My personal experience was quie the opposite. My car launches hard with much less ESP intervention or wheelspin with the PS2s. While I have not had the chance to officially time my car on the new PS2s, I can no longer spin the tires on 2-1 downshifts like I could with Pilot Sports.

when I get my G-Tech back, I'll run my favorite "strip" again.

 

dude, 1.8 60ft time on street tires is damn good, take it from me I've got a lot of passes under my belt.

What did you do to your E for it to run a 12.15? That's considerably faster than stock.

 

Your results are quite the opposite to everyone else's experience. My ESP amber used to light up non-stop with the 265 Contis, hardly ever with the 275 PS2's.
O-62mph 5.2 sec on Contis, 4.4 sec on PS2. Lateral G's on Contis 1.0G, PS2 1.09G. So, in a straight line and around corners PS2 are superior! Drag times were similar for both tires despite the Contis running on a warm dry night and PS2 on a cold, dewy track surface.

 

Dude, who said PS'2, one of the greatest cornering street tires, would help you get the wholeshot on the the guy in Lane 2?? You want hook, buy a set of BF Goodrich Drag Radials, they'll hook til your half shafts fall out.

I think it goes (for dragging) contis=yugo PS2's=stang gt drag radials=pro stock mickey et's on custom made rims=funny car.

If you are that serious about taking her to the track, buy a set of stock AMG rims mounted with drag radials from tirerack.com, Luke sold me mine complete, mounted and balanced for around 1500$

Good luck.

 

PS2s are street tires. They are a compromise. I still agree with others however that they hook up better than Contis. I routinely would trigger ESP when shifting from 1st to 2nd. 275s rarely do it.

 

I'm going to head to the track once the weather gets a little better here. I'm running S03's and they seem to hook up great around town. Hopefully, I'll get the same result at the track.

 

Lets not everyone get wrapped up in the common knowledge that PS2s are the best in all circumstances. AmenMercedesGo has said that he has gone to the Drag Strip twice with the PS2s on his E55 and has lost some performance when compared to the Conti's. The Man has empirical evidence to back his conclusions up (assuming he is being truthful and there is not some other problem with his car now and that the weather and track conditions were the same). He might have found a niche that the Conti's perform better in, than the PS2's. All be it, a very small niche, given the reported over all satisfaction with the PS2's performance over the Conti's. reported here on this Forum. BTW he obviously knows how to drive the E55 on the Drag Strip as evidenced by his 60 ft. times and his 1/4" times. Food for thought! - Bob

 

Stock Contis are 265s and most get 275 PS2s as mentioned above it might be the difference in the diameter of the tires that makes the car effectively have a tall rear end gear. Maybe we might need to stick the stock 265 size. I wonder what the height of 19" 275s are?

 

Use the size marking to calculate the diameter as follows: 275/30/19:
275mm width x 30% aspect x 2 (top and bottom of tire) + 19" x 25.4mm/inch rim diameter= 647.6mm / 25.5"
265/35/18= 642.7mm / 25.3" STOCK rear
275/35/18 = 649.7mm / 25.6"
245/35/19 = 654.1mm / 25.75"
245/40/18= 653.2mm / 25.7" STOCK front
255/35/19= 661.1mm / 26.0"
295/30/19= 659.6mm / 26.0"
285/30/19= 653.6mm / 25.7"
Both OEM combinations of 245f/265r in 18" and 245f/275r in 19" leave the rear tire 1.6% and 1% respectively smaller than the front. Ideally it should be 245/35/19 on 8.5" and 285/30/19 on 10" rims as both are 25.7"
This perfect balance is short lived as the rear tires wear out so much faster and once they are half worn, you are down to 647mm / 25.5" anyway.

 

Thanks guys for kicking this issue around. I was very aggravated when I got home from the track last night. For one solid year I have ran this car at the same track, I went through two sets of rear conts before going to P2s all the way around. Two points I'd like to make now that my emotions have subsided. One, the difference in diameter is nominal, but the difference does change the gear ratio for quarter mile performance. Two, the cont's (at the same track with identical weather conditions) do not require but a brief spinning to bite solidly off the line but once off the line with (1.7 60ft times) they chatter as the torque comes alive acting like a slipping clutch or stall converter letting the motor twist up. The P2s after spinning hard do not heat up well. Off the line they slip just like a improperly inflated drag slick for just a split second and then solidly bite never allowing the motor to pull hard. The result, the motor is not in its' sweet spot and the small gear ratio loss equal a loss of et.

 

Gearing ratio differences (+/-1%) are so miniscule that they would have been eclipsed by all other variables: ambient temp, track temp, relative humidity, etc.
I ran 12.35 sec on worn out Contis with 640mm diameter on a warm/cool, dry night. A few weeks later, on a cool, clamy, high humidity night, where the track felt "sweaty'' and everyone complained, I used PS2 with full tread at 650mm diameter and got 12.41 sec. The slippery track alone should have pushed me into low 13's. PS2's leave Conti's for dead in everyday driving, both in "traffic light Grand Prix" and around corners. My G-Tech data proved it!

 

I ran 11.95 @ 118 w/ conts on g tech pro and 12.17 @ 116 w/ P2s on exact same stretch of I-20. Attached prior posts and proof of driving ability. In the late 70's early 80's prior to being a successful attorney I ran IHRA in the southeast stock division. I want what is best for all members.

 

Attachments too large. oh well

 

Read my signature for links and instruction on how to post large pictures.

 

I dont know if I agree with the killing of the gear ratio too much. These cars have a relatively deep first gear, not to mention prodigious torque. Also, most people who run drag radials run a 275/35/18 with great results.

 

Tried Attachments again! Slow run again today.

 

Just get yourself some drag radials for when you go the track.

 

medici78 - I think what AmenMercedesGo is saying that a stock E55 needs to slip a little more, than the PS2,s will allow, to get into the sweet part of the torque quicker, and that the tire size ,that is just a TAD smaller, does make a difference. - Bob

 

Check out video through your search engine. type in scmc 2005 video pics and scroll down til you see the download. I and my friend with his 2005 slk55 competed earlier this year. He ran a 12.80. Maybe Derek should come to our track to check out the traction one thursday night on grudge test and tune.

 

Fair enough. Interestingly, this is why I suggested a higher stall converter, but everyone seemed to shoot that idea saying there is more than enough torque to start with.

 

Isn't wheelspin always a bad idea? Can't you just power brake to get to the torque range you want?

 

It depends on how the car is set up. In this particular case, a little more spin is better than a little less. Dragsters use some clutch slip as well.

You can only PB as high as the TC will let you. It might not be high enough.