Hi all. Finally got a chance to take my LS out and stretch its legs a little. 2:00 am on a deserted 4 lane. Everything running along smooth as could be until about 4000 rpm, showed about 144-145 mph. Felt like a speed limiter kicking in. Are these cars governed, or was it just not getting fuel? Running premium 91 oct. Not a delinquent, just wanted to open it up a little and see what she'd do. I was thinking top speed was supposed to be about 155 or so. Brand new Michelin Pilots handle the high speed traction chores. Anyone else run into a limitor, or was this some kind of mechanical duress?

I'm guessing an SCT XCal 2 will remedy this problem. Although, if you're not tracking your car, I wouldn't necessarily think that being able to ONLY drive 145mph is much of a problem ;)

So, I'm guessing that there is no fuel shut-off limiter, then. Not a big deal, just wondering if it was like other vehicles I've owned that try to control your driving habits. I'll run some injector cleaner through, and check the regular maintanence items, as I don't track it, or drive fast often enough to justify reprogramming. Thanks for the advice, though. Is 155 about right for top speed, how many rpm's would that be on an auto (v-8)?

Actually what I meant was that there is probably a speed limiter, IIRC. But you can get a custom tune for the XCal2 (a custom tuner available for the LS) that would take care of that for you.

With the XCal2 the speed limiter can be turn on or off or set the govern speed yourself.

The LS is electronically limited to 140,(according to the owners manual), due to the stock tires. This is the only reason. Allot of car mfg's do this, for their tire selection on the new car.
I understand the SCT XcalII removes this.
I saw on a thread somewhere here, that someone showed 157mph, with the XcalII tune installed.

Thanks for the info, guys. I figured it was here, somewhere, just didn't feel like reading 20,000 posts to find it. I'm guessing my stock tires were firestone's (firehawks, maybe?), as that is what is mounted on my full size spare. I don't plan on driving over 100 on a regular basis, so reprogramming is moot for me. But it's nice to know what the car can and can't do. Either way it is the smoothest high speed drive I've ever had.:D :D :D

Got bored one day and picked out a nice paved straight, flat country road and hit 134mph @ 4k-ish rpm.. I was a little bummed but things sure do fly by at 130+ needless to say i havent been over 100 in a while.

The Pre-03 LS without sport package was limited to 133mph.
The Pre-03 LS with sport package is unlimited.
All 03+ are limited to 133mph.

The SCT tuners can remore the limit.

So it sounds like you have a pre-03 with sport package - and they simply peter-out at 147mph.

With lowering and some tidying up of the body work we have hit 153mph - without any power adders or tuning.

What kind of tidying up are you referencing there Quik?!?!?

:-D

I'm guessing it's the sport as it has the spoiler on the trunk and the sport option code. I think the problem may have been a coil not wanting to fire correctly at higher rpm. I had throttle maybe 60% open, it's not like i was racing to top speed, just letting her stretch a little. This car is COMPLETELY stock, so I'm not disappointed at all. I know it's never been driven this fast, so we're taking our time getting acquianted and learning a little about each other:D :D :D :rolleyes: :rolleyes: :rolleyes: She has expensive tastes, and she's a little bit high maintanence, but we're going to get along just fine. When the roads clear, and we have a nice 30degree night, we'll go back out to the 4 lanes again and coax her a little more...nice and easy:cool: :cool: :cool:

i've never got mine too far over 120, then again, i havent quite pushed it that extra bit, tend to run out of road or am on an interstate...going to check into it though...

i only drove my ls up to 83, i just got my car Friday, and it went back to the dealership due to some severe shaking on the highway so after i get it back, I'll push it up to 120 or so, i never driving 120+ in any car, but I've been in a car that people have drivin 130+.

2000 LS V8 have a limiter too ?

What kind of tidying up are you referencing there Quik?!?!?

:-D

the body kit, front splitter, lowered, and I added a rear difusser. I noticed on my previous runs the air pocketed up behind the rear bumper and actually popped the rear assist sensors out....

hereis before and after

looks very nice.

where did you get the diffuser?...did you make it?...and why havent you added aftermarket wheels and tires yet?...

yes - homemade.

I actually like the silverstars I have, and since I'm lowered 2" I do not have a lot of options.

I autocross - so I am on my fourth set of tires (fifth set of brake pads), not as interested in new rims for apperance shake only. some new lighter and wider rims - no that may work....

there is mine 2001 Ls V8 and it just stop there there is a speed cutoof cuz by the rpm it can go more i were on fifth gear on fourth i can get to 142=145 too but my rpm would be redline
http://img176.imageshack.us/img176/704/dsc00933oj2.jpg

Both my '05 and a rental '06 hit the limiter at 132-134 indicated. I highly doubt that's 140mph actual, the speedo in most cars indicate 2-3% fast so the actual is going to be under 130.

I'll be I've hit my limiter at least 50 times. OK, so I'm comfortable with high speeds....

For the guy posting this thread, the way mines pulling when it hits the limiter, it would pull at least 150 if allowed to run on, maybe more. It's pulling pretty well at 130.

For Mr.RearDiffuser (QuikLS), AWESOME!!!! The air pressure of the air going by at top end is so low, and the air pressure so high under that bumper those sensors might pop out anyway. The diffuser is just going to make air exit more efficiently, which should help top end for sure and I'm curious what the gain was.....and again, nice work, You're not doing anything I haven't wanted to but just can't get to!