Uh...as an owner of a 2nd gen, It sure doesnt look like those catfish.
And the 612 mimics a lot of the 60s and 70's front engine Ferrari GT cars, and that is where the 2nd gen got most of its design influence from. The 612 looks very close to a modern 70-73 Camaro, complete with circular tail lights.

And I like that quote in your profile

 

From everything I have read the 4th gens had a 162 limiter for cars with Z-rated tires. They usually have a margin of error +/- 3 mph. A little tuning, and that is no longer an issue. Mine is set at 255 mph now (or whatever arbitrary number tuners use, basically somewhere your car will never obtain).

 

But 98-02 does look like a 79 with the Open grille that hints of the 70-73 I think. But no its not just like the catfish, I never thought of them that way before.

Thanks on the quote. It was an old slogan people used where I work internally to remind everyone that the way clients see you if only a short while is their reality of the way your company is. It can make or break you. It stuck with me. I dont know where it came from but I like it and thought it appropriate.

 

I'll be the upmteenth person to confirm that the LS1 Z rated tire cars do have a 160soemthing speed limiter in addition to their 6200rpm rev limiter.

Top speed isn't an exact science because the speedo isn't quite dead on accurate at those speeds so sometimes you'll see 159, 163, etc....


I THINK the LT1 z-rated cars had no top speed limiter.

The story I've heard as to why the LS1 cars were limited to 160something is because the driveshaft was only capable of that speed before it hit "critical speed" and was at risk of causing all sorts of problems. It certainly wasn't the tires, they were the same GS-Cs that were on unlimited C4 Vettes which ran faster than 160.

Of course, now that I've got my LPE driveshaft with a 200mph critical speed, it's time to clip that 160 limiter and open her up looking for 170+!

I agree with everyone that says aerodynamics are WAY to complex to judge by eyeballing this concept. If the brick looking 300C SRT8 can run 170+ with 425 hp, it's entirely possible that the 5th gen will be able too. Can't judge it on looks.

 

Are they? Don't the RSAs on the 3rd gen Mitsu Eclipses and the RSAs on the 4th gen fbodies carry a different speed rating? At least I thought they did, but I could be wrong. Tires on both cars are still Goodyear RSAs.

 

FWIW, I remember back in 1999, a Canadian publication (Canadian Motorist? - I honestly can't remember... and the article isn't available online any longer) had a top speed shootout on the banked oval at Blaineville, Quebecl between a Ford Lightening and a Firehawk. Umberto Bonfa, who was the Canadian Sales Mgr. for SLP at the time told me that the Firehawk that he brought to the shootout had the [B]speed[B] limiter removed and that car managed to pull an honest 170+mph on that banked track.

best regardSS,

Elie

 

I really wish I could get a copy of that article. Not on the net anymore huh? I wonder if someone has it and could scan it?

 

All Goodyear GSCs are Z-rated, RSAs can be H-rated or V-rated.

 

I have a Road & Track video tape from 1995 that is called Fastest Cars in America. They tested 5 completely stock cars, and then 5 of the same models that tuners sold as pkgs. The Lingenfelter Firebird 383 NA had the fastest top speed of the test. I believe it was 196 mph, which even beat the Lingenfelter Corvette ZR1.

Off the top of my head other cars that were tested: Camaro Z28, Vortech Camaro Z28, Mustang GT, Saleen S351, Viper and Hennessy Viper

 

You could order the "Z rated" option and get GSCs, or the "Z Rated All Season" option and get RSAs. They are both Z rated tires. Goodyear makes a lot of other RSAs with other speed ratings, but the ones that came on the camaro were Z rated.

The Z rating has been subdivided in recent years. Z was just 149+, and that was it for a while. There's W and Y now. W = 168 and Y = 186.

In any event, the driveshaft was a limiting factor, the stock LS1 shaft can't handle much more than 162mph according to LPE.

 

Correct, and RSAs can also be Z rated.

 

I hate to get into the middle of a rev vs. rpm limiter argument but wanted to share something I've always thought strange.

I used to have a 1994 Lumina Z34. It was an automatic and once hitting around 120mph the car would shift into fourth gear and stay at the same rpm & speed no matter how much you pushed down on the gas pedal.

I eventually discovered that if I put the car back into third gear, I could run all the way up to redline until fuel cut off which was so obvious around 135mph. A few mph drop and the engine would turn back on but shift into fourth at any point and the car would slow down to 120mph . . .

I've never understood limiters because of this. Stuck at 120ish in overdrive but fuel cut off deep into redline around 130s? Was this drag/gearing or rev/speed limiting?

 

You couldn't go faster than 120mph in 4th gear because you simply didn't have enough gear to keep the rpms higher in the powerband, so the car couldn't fight the aerodynamic drag. When you held it in 3rd gear manually, your car had the benefit of better torque multiplication at the wheels due to the direct drive property of 3rd gear as opposed to the overdrive property of 4th, and the rpms were at a better point in the powerband to fight the force of the air. When you would wind the car out in third gear to redline, that is rev limited. When you couldn't pull any further in 4th gear, that was drag limited.

 

I think what RussStang said is correct.

Now for some random Lumina/Grand Prix/Cutlass 3.4 DOHC trivia: I had a 95 Cutlass Supreme Coupe 3.4 "Twin Dual Cam" (pretty much the same as your Lumina Z34) - and I recall it having a speed limiter somewhere around 130 to match the H rated tires it came with - as well as a rev limiter. I don't know if you remember this, but if it was like my 3.4 cutlass, it also had a unique, lower rev limiter in park - of something like 2500 or 3000 rpm. Interestingly, not in neutral. And, it had a speed limiter in reverse - you could only go about 20 or 25 mph in reverse before you hit it.

 

Its hard to imagine that is true. My civic, while not a chevy was limited to 100mph in 4th gear. The RPMs would stop increasing, but if you knocked it down to 3rd you overcame the speed limiter. Once past the 110 mark then back to 4th and the RPMs would now increas in 4th and keep going to 125 130 if you had the road, but thats usually when I ran out of road. But the limiter was completely overcome. I think what is more likely is that the programming for the computer is that if the car is in fourth AND once you hit 120 you get no more fuel. Especially if you step down more on the gas and arent getting more RPMs.