[chazglenn3]

Are the 1SF cars that were delivered with the 17" wheels speed limited? I thought that I read that the OEM tires were V-rated, but the sticker on the drivers side doesn't show the tires were speed rated. I'm pretty sure the 1SG cars with the 18" performance wheels package are not limited.

 

[ECha3]

I think all the cars built for the US market are speed limited to about 10MPH lower than the rated speed of the OEM tires. Check the tire label on the drivers door frame.

 

[chazglenn3]

That is the label I mentioned in the OP. It shows no letter at all. That was why I was questioning the 1SF with 17" wheels...were they V or W rated from the factory? Given the label on the drivers door it looks like they were not. The STS4 with 1SG I was looking at showed W rated tires from the factory. According to this post http://www.cadillacforums.com/forum...gh-2010/197257-those-1sa-1sb-1sc-1sd-1sf.html the 1SF package came with Michelin V-rated tires.

 

[ECha3]

Mine were 'W'. I've never reached the limiter. Maybe the build sheet has it.

My wife's car was a Hertz car and came with S-rates tires (QKP) and has a low limiter (106?). The OEM tires were crappy Michelin Energy hign MPG & rock-hard. I did hit the limiter once (after upgrading to better tires.)

 

[chazglenn3]

Yeah, your car is 1SG like the STS4 I was looking at was...comes from the factory with the W-rated 18 inchers.

 

[ECha3]

Do you have a 'Q' code on your spare tire cover label or build sheet? Q12 is for my 235-255 18 W's.

 

[chazglenn3]

Mine is Q11...TIRE ALL P235/50R17 FRT & P255/45R17 RR TIRE(Q11)

 

[ECha3]

I'd bet your car came with W or better (Michelin Pilot Sport?). The limiter is probably like mine one-fifty-something. I think top unlimited speed is 168MPH.

Anyone with Q11 know their OEM tire speed rating?

 

[jimmbo]

Anyone who is testing the limiter on public roads certainly needs an attitude adjustment. An extended stay at Hotel Greybar for starters.

 

[grosserhund]

Anyone who is testing the limiter on public roads certainly needs an attitude adjustment. An extended stay at Hotel Greybar for starters.

Perhaps a trip to the psycho ward would be in order - place the patient in a spherical room and tell him (or her) not to come out until finding the corner

 

[next2pool]

Rental unit. Regardless of package and option codes you may have a spo code.

 

[Platinum06]

120... 07 AWD V8. Wish there was something I could do about it.

 

[ECha3]

120... 07 AWD V8. Wish there was something I could do about it.

There must be a good Tuner Shop in Phoenix. They will know what to do.

 

[chazglenn3]

Rental unit. Regardless of package and option codes you may have a spo code.

What is a SPO code and where would I find it?

 

[wileyf]

With the factory W-rated 18 inchers. your top end will kick out at 140 +or- 5mph. Mine did.
Yea I was on an interstate in broad daylight w/3 other vehicles covering some ground. Super light if any other traffic. dumb? yes. Fun heck yea. Oh I forgot to mention It doesn't burn oil any more either. Just in case you were interested.

 

[ECha3]

Years ago, a member posted all the tire & limiter combinations at that time. I haven't figured out the new search function but that would be a good prize.