Hoose

I recently replaced my 2002 V6 camaro with a 2000 z28. Early this morning I finally got a chance to drive it fast. However, at about 115mph, 4k Rpm in 5th gear the car just started jumping back and forth kinda like a car trying to take off with someone who doesn't know how to drive standard. I took my foot off the gas pedal and slowed down and it worked fine, but as soon as I tried it again, the same problem occurred. What is this? Any help would be much appreciated. Thanks.

2001NBMZ28

Sounds like you might be hitting the speed limiter - look at the tire information on the drivers side door and see if it came with Z rated tires.

klujan13

iTrader: (11)

sounds like a speed limiter prob to me too.

kenny

Hoose

At 115ish mph? That's pretty lame. How do I fix it?

LS1SpeedAddict

iTrader: (9)

re-flash, any tuner can do it or you could get a hand held programmer.

2001NBMZ28

It can be programmed out of the PCM, even the handheld programers will do it. Believe the cars with Z rated tires were limited at something like 160?

Hoose

where would I go to get this done properly? I mean i've heard stories of people messing with their car's electronics with some horrible results. Like I don't want my car to not idle or to get like 5 MPG. Would a chevy dealership be able to fix this for me?

2K2WS6TA

iTrader: (2)

First get some Z rated tires, then get one of the handhelds that will take out the limiter, or you could find someone local with HP tuners/LS1 edit, pay em $50 and have them remove it.
The dealer might, but not likely (they don't want the potential liability)

2001NBMZ28

Yeah, dealer can do it, but probably wouldn't unless you know somebody there. Just removing the speed limiter won't affect anything else. Look for a shop that does dyno tuning in your area, usually a minimum 1 hour shop charge around here.

Hoose

Thanks a lot guys, I really appreciate all the help. I'm gonna look into finding someone to do it for me, I'd probably **** it up.

seawolf18

iTrader: (18)

A 2000 Z-28 shouldn't be limited to 115?

klujan13

iTrader: (11)

some f-bodies came with lower rated tires and those few select were limited at like 115 you gots to check the tire rating on the door sticker....like 2001 said above

Swang

iTrader: (3)

you said in 5th gear....if you have a 6spd...you should have the 162 limiter...if youre refering to OD then its just the governor kicking in...some z28's with 235 tires came with a limiter of 115.

300bhp/ton

No body has really mentioned it. You need to check your tyres also. The limiter exists for a reason. If your tyres are only rated at that speed and you remove the limter and drive at high speed then you stand a very real chance of the tyres exploding. Need I really say more.

HeapaShifter

iTrader: (2)

I work at a Chevy dealer and we have no access to anything that can remove a speed limiter. We can reflash PCM's, but only with every parameter pre-programmed. No modifying individual things. The Tech 2 scan tool can't do it either.

You'll need to go to a speed shop or get a handheld programmer. Something like LS1 edit can also do it, but it can be complicated to do yourself.

camarrowz28

The limiter on my 2000 z28 was set that low also because of the tires, at 118 actually. When I had my dyno tune I had them change the limiter to like 255 or something.

1LoudTA

iTrader: (11)

tires exploding my *** i did 135 in my iroc with some H rated BALD tires. i think they were rated at 90mph or somethin. its good to be young and dumb

2K2WS6TA

iTrader: (2)

They won't instantly explode if you exceed the speed rating, but sustained driving in excess of the rated speed, they can and will go BOOM
And BOOM going 150+ will really ruin your day (or your life)

natronathon

anyone with hptuners can do this. it is as simple as just entering 160 in the box instead of 115. Would take 2 minutes max. VERY SIMPLE. Just go into the regional forum and see if there is anyone willing to help ya for a few bucks or a 12 pack. I'd help ya if i could edit a 2000 and if you lived near wichita...

300bhp/ton

Then you're a prat and should not be advising such BS to other people. Tyres can and do explode or degrade at speed. How on Earth do you think they came up with the ratings in the first place, computer simulators didn't exist in years past. They used to actually use the tyres at speed and find out when they expire.

If you got away with it, hooray. But it doesn't mean every tyre out there will be safe and work at speeds above that which they are rated at.