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One of my buddies at work has a last body style (2000ish) Z28 that was modded by the guy who owned it before him. It's a 4 speed auto that's had 411 gears put in, as well as a CAI and a loud as Jesus (obnoxious, like open-headers loud) cat-back exhaust system. He says the cars top speed is around 120 mph. He's running like 3500-4000 rpms just going down the road at interstate speeds.

I knew all this when we played on the interstate after work. We took off from a 65 mph roll and he pulled on me slowly but steadily up till about 95 when we let off for traffic. I just got a K&N CAI, Borla exhaust, and Diablosport tune, so not modded for bear. I called him on his cell as soon as our little race was over. He was laughing at me telling me he's only got a 350 and I got a 400 (he doesn't know what he's talking about, needs to do his homework) and his 350 beat me.

I laughed back and told him that he's got a nice 1/8 mile to 1/4 car, but after that I'd eat his lunch. He asked me how do you figure. I told him that I can run 120 in 3rd gear (I also have the 4 speed automatic) and got another 43 mph past the 120 in 4th gear. He said it doesn't matter because you never use that kind of speed and getting to 120 fast is all that counts. I guess I can see his point, but still......if I get to do what I want with my tax return money (cam and headers) I'll challenge him again without letting him know I did anything and see how the results end up. I'll keep you all posted.
 

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Sounds like it was a close enough race to determine the obvious outcome at higher speeds, your right about higher speeds.

This guy really sounds like a moron.
 

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I know how you feel. My brother has a 87 formula (work in progress) built to about 500hp and he's well over a full second faster than me on the 1/4. I just tell him at least my car gets 28 miles to the gallon on the way to the track and doesn't look like it belongs in the trailer park. Plus mine is pretty much stock and if I throw a few parts at it he'll be in trouble. Even if some of our cars are stock we can still have fun and take pride in what we have. So when this guy with the camaro needs to stop for gas three times on the way to the track or gets pulled over by the cops for his car sounding like some hillbilly pickup just point and laugh!!!
 

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I wouldn't worry about it much since his car is getting a little too hot if its running at 3500-4000 rpm on the interstate. It sounds like the stall on his converter is a little bit too high if he is only pumping out 350 hp. Also, don't really think he has 350 hp when it actually might have more if he pulled on you. Our cars can hit 120 without a problem and am sure his would too if his stall wasn't so high. His car does not sound like a fun car to drive since its kind of limited in what it can do. He also sounds like he doesn't know too much about f-bodies or other cars if he's claiming bragging rights on something minor
 

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I wouldn't worry about it much since his car is getting a little too hot if its running at 3500-4000 rpm on the interstate. It sounds like the stall on his converter is a little bit too high if he is only pumping out 350 hp. Also, don't really think he has 350 hp when it actually might have more if he pulled on you. Our cars can hit 120 without a problem and am sure his would too if his stall wasn't so high. His car does not sound like a fun car to drive since its kind of limited in what it can do. He also sounds like he doesn't know too much about f-bodies or other cars if he's claiming bragging rights on something minor
:agree
My buddies Evo 9 is a 5spd and hes cruising at 3300 rpm on the highway at about 75-85 I'm not too sure, but I've seen it. While I'm just under 2,000 rpm cruising at 80 and getting 25mpg :D
 

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One of my buddies at work has a last body style (2000ish) Z28 that was modded by the guy who owned it before him. It's a 4 speed auto that's had 411 gears put in, as well as a CAI and a loud as Jesus (obnoxious, like open-headers loud) cat-back exhaust system. He says the cars top speed is around 120 mph. He's running like 3500-4000 rpms just going down the road at interstate speeds.

I knew all this when we played on the interstate after work. We took off from a 65 mph roll and he pulled on me slowly but steadily up till about 95 when we let off for traffic. I just got a K&N CAI, Borla exhaust, and Diablosport tune, so not modded for bear. I called him on his cell as soon as our little race was over. He was laughing at me telling me he's only got a 350 and I got a 400 (he doesn't know what he's talking about, needs to do his homework) and his 350 beat me.

I laughed back and told him that he's got a nice 1/8 mile to 1/4 car, but after that I'd eat his lunch. He asked me how do you figure. I told him that I can run 120 in 3rd gear (I also have the 4 speed automatic) and got another 43 mph past the 120 in 4th gear. He said it doesn't matter because you never use that kind of speed and getting to 120 fast is all that counts. I guess I can see his point, but still......if I get to do what I want with my tax return money (cam and headers) I'll challenge him again without letting him know I did anything and see how the results end up. I'll keep you all posted.
I'm with your friend. Getting down the quarter first is the traditional measure of speed. Having a car that'll do 170 is fun but not practical most of the time. The heads & cam on your car should send your buddy back to the speed shop for more mods.
 

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I wouldn't worry about it much since his car is getting a little too hot if its running at 3500-4000 rpm on the interstate.
What? Explain your reasoning.
It sounds like the stall on his converter is a little bit too high if he is only pumping out 350 hp.
You always dyno with your torque converter locked.
Our cars can hit 120 without a problem and am sure his would too if his stall wasn't so high.
Explain how a torque converter would affect your top speed.
 

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I'm basing my opinion on the observation I saw several years ago on my buddies 02 Z-28 camaro on a trip to Gurnee from Chicago. His car was dynoed at 389 hp (comp cam, headers, and other bolt ons) with an after market stall converter and know what you mean about locking the converter while dynoing it. On the way there, we were doing 70 mph and the car was at 4000 rpm which was alarmingly high since it wouldn't go faster than 80 before we noticed that his transmission was not working properly. His overdrive was not responding at all and something was up with his converter and he had to take it back to his speed shop to have it looked at again cause he picked it up 4 days before. It affected his top speed cause it was not stalling properly, once he got it fixed he was doing mid 12's on the quarter mile in Joliet and hit 155 on the way there
 

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My stock geared Z28 will run 158 mph in 3rd gear at 6100 rpms. This is taken from 2 different road tests of cars with the stock 2.73 rear gears.

With a gear change to to 4.11's, the car would run 105 in 3rd. My car runs 1850 rpms at 75 in 4th so with a .66 reduction in gearing his car would run about 2800 rpms in 4th. He would be at 5600 in 4th gear at 150 mph and redline, 6100, would be 163. His top speed would fall somewhere between 142and 163. 5300 being about his power peak and 6100 being his redline. My guess is 154-156 which is around 5800 rpms.

The car probaly has a SLP Loudmouth exhaust which is best described as obnoxious. They have a huge problem with resonance inside the car with that exhaust on A4 cars. There is a small resonator and no muffler. You can drop a golf ball in it and it falls straight through. It's not leagal in most states due to noise.

I'm thinking of going to 3.42's. That will have me at 126 at the top of 3rd. Trapping at 110 miles per hour in the 1/4 will put me at 5300 rpms, a nice sweet spot. At 75 I'll be turning 2300 rpms. A bit high but liveable. Add a torque converter and I'm now looking at mid 12's if I can get traction.
 
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