grandotitat

I'm opening this thread just to share exactly what the title says. Recently I bought a 2003 Z06 which I imported into my county. You can read the whole history here if you're interested:

https://www.corvetteforum.com/forums...adventure.html

So, when I drove my car in the US from the dealership in Orlando to the docks in Miami, it was the fastest car ever. I really felt my guts trying to leave my body while accelerating. However, when I received the car in my home, the city of Bogotá, Colombia, located at 8530 ft above the sea level, I felt I was driving a different car. Besides, the best fuel we can get at the city stations is 87 AKI (91 RON).

Anyway, the car wasn't that slow either but the only way to know how much power I lost, was a dyno run and a 1/4 mile run. The car specs you find on Wikipedia say that this car is able to achieve 11.9 (assuming sea level and good fuel) , but I seriously doubt about this. The best I've seen for stock C5 Z06s is something around 12.9 but you can correct me. So, my first step was the 1/4 mile run, and the results were within my expectations:



Yes... 14.1 For the 100% stock C5 Z06 at 8500 ft of elevation with 87 octane (aki) fuel on the tank. Here's a short video:


Pretty slow for what you should be used to eh? I did 4 passes using and not using the traction control. The difference was 14.2 with T/C and 14.1 without T/C. I have purchased a few light mods and I expect to drop my time somewhere within 13s and I'll be happy with that.

The next step is the dyno run. I'll post the information as soon as I get this done.

Everyone with C5 Z06s living at high altitude is welcome to share their experience!

dart.deanda

I bought mine at 5200 ft. Was still incredibly fast. Moved to Australia near the ocean and now Florida near the ocean. Way faster. I also raced near great salt lake and the lake steals oxygen from the air. So the DA was like 7800 feet even though the altitude was 6000... stock c5zs run as low as 11.7 check the fast list

ZZOOM06

The most common formula for elevation is the fact that you lose 3% of your sea level horsepower per 1000' of elevation increase. I live at 7550' above sea level so on a standard day my car makes 22.5% less horsepower than at sea level. During the summer months I have seen Density altitude here as high as 12000'. Driving the car here on a hot summer day is somewhat less than fun! Only way to get around this is to do forced induction, either supercharger or turbos. HTH

Jimbo

racebum

those aren't exactly stock

that's no lift shifting, god knows what else. no one has inspected the cars or verified the claims

the fastest ever doc'd showroom stock car even driven hard was something like a 12.3

many people on car forums lie and there is a lot of filth on this forum. so, unless you inspect the cars, times have to be taken with a grain of salt

for the altitude, OP did pretty well, lot less oxygen up there, car was probably down a good deal of hp, gas also didn't help. for roughly 300hp that's about the time you would expect. probably could get in the 13s with some practice

Trash

Given the altitude you have a difficult battle. You should be able to get your 60' time closer to a 2.0. That alone would net .4 sec and you'd be near the mid 13 second range. At your altitude I suspect an optimally driven car would be in the 13.3-13.5 second regime.

I have been able to match or beat published magazine specs in a bone stock car but only after a lot of trial and error.

BLEKVET

Get meth injection. That will definitely help whether you stay NA or go FI. I understand your frustration. My Z makes 490 rwhp in Arkansas and about 25-30 less in Colorado. Besides adding meth, get a tune.

Good luck. Enjoy your Z bro.

LT1driver

I think Ranger has gotten some of those fantastic 1/4 mile times and now doing same with a c6zo6. I live in Texas and took car on trip to colorado springs colorado and boy did it lose power, DA 5-7000 feet in area....ouch. On the other hand you could be driving a prius or other small car with 4cyl and then you would understand "gutless car"....

Johnny wangwang

To be perfectly Honest Grando....its not the car its you. You should be running 2.0 60fts at least. If you launch the car better and get a 2.0 60ft or better youll be sitting at a 13.0-13.2ish time.

Right now your 60ft is a 2.5 which sucks even for a FWD car. Practice your launch and check and make sure that your tire pressure isnt too high.

grandotitat

Well, I'm pretty sure I can do better, but in this track I've never seen 60 ft under 2.2 for non awd cars, unless they are running on slicks or drag radials. I've been doing 1/4 mile since 8 or 10 years ago but this is the first time I run an RWD car. Unlike drag strips in the US, the slicks sticky compound they apply here on the pavement is only used for the 60ft and a little bit further, and not in the whole width of the lane, so in this way the cars with radial tires can run in full contact with the pavement. When I was launching the car, I felt the tail was sliding a little towards the right side so probably the left tire touched the slicks compound helping to the traction loss. Honestly I see very difficult to reach a 2.0 60 ft. That is what most Subarus are able to accomplish here and I can't imagine an equivalent launch with an RWD car. But as you are telling me, practice here is everything and probably I'll be able to get down at least 0.2 on the 60 ft.

I'm looking foward for the next 1/4 mile championship in the city of Barranquilla located at sea level where I can use race fuel and see what this car is capable of with the ideal conditions. Unfortunately I'll have to wait until February 2016 but I'm not in rush.

Thank you for your insights!

Johnny wangwang

For every .1 you take off your 60ft you get about .2 on the big end.

Take a Video of you launching the car next time. From there we can help more. Also what tire pressures are you running at the track?

janky

Any NA engine is going to be very underwhelming at those altitudes. Turbochargers rule the roost because there is some degree of compensation to be had for the drop in ambient pressure.

grandotitat

Yeah. I Took my GoPro with all the mounts to record everything and I forgot the memory card on my home . And about the tire pressure, good point to check on that. I have no idea! In fact, I haven't even checked the tire pressure since I bought the car in December. By the way, are the readings on the dashboard reliable?

Trash

I know it may seem nearly impossible to reach the 2.0 60' time. I used to think that too. I started in the 2.4x range, got it down to 2.2x then a bunch of 2.0x stuff. I was convinced I could crack the "2's".

Unbelievably I finally did with a 1.999'. Then I wasn't satisfied and whittled off a 1.97, then a 1.94 etc. Pretty soon I broke into the 1.8x (whole string of them) with a 1.826' being the best. After that run I was like 'crap!' I'm close to the 1.7x! Unbelievably I cracked off a 1.787 on Continental DW Extremes aired to 25 psi, DA was about 1800'. I now think that is the approximate limit for those particular tires.

Good luck!

ptindall

87 octane at 8500 feet is probably perfect. Higher octane would not help. With the higher altitude, you have lower cylinder PSIs, and therefor less need for higher octane. I would bet the car was not pulling timing at 8500 ft on 87.

ptindall

A Z06 does not have tire pressure readings unless it has been modified.

Moto One

As noted, 87 oct @ 8700ft is about all you need, running a higher octane with out some sort of forced induction at that altitude would cause a miss at full throttle load, because it just can burn the slower burning hi octane. We live at 7000 elv and it feels like 20% down, but then feels great when I'm off the hill.

Mark

TurboTnZ06

One day it was hot in Denver, I could only run 13.8 at 103 mph. The DA was over 10,000 ft that day. Same car and driver, no changes, just in the winter in Florida at sea level with a DA of -500 ft, ran 12.3 at 115.

grandotitat

Wow man, that is amazing. I mean, those 60ft are reserved here for dedicated race cars or AWDs. Next time I'll check the tire pressure and see how that helps. Now I'm running Bridgestone Potenza RE760 Sport
tires. The thread wear on those is 340 which I think is not positive for traction.

Well, I just dynoed the car and the graph revealed a pattern usually seen in cars trying to make corrections to avoid knocking so probably I'm not 100 safe even at my altitude. It doesn't looks to serious but I think a re-tune will be necessary and I'll get into it as soon as possible.

I'll post the dyno results shortly.

If I push the "Gauges" button on the dashboard, eventually I will reach this screen:



It will also read "FRONT". So, considering what you're telling me, which kind of modification my car has to achieve this reading? Thanks for the info.

grandotitat

I finally had a little time to take the car for a dyno run. The results were within the expected. Remember this Z06 is 100% stock and at 8500 feet above sea level. Fuel in tank is 87 octane AKI (91 Ron). The equipment used to do the test was a DynoJet in one of our local performance shops named CARTUNER located in the city of Bogotá.

Check the video and post your opinions!

Moto One

If I push the "Gauges" button on the dashboard, eventually I will reach this screen:



It will also read "FRONT". So, considering what you're telling me, which kind of modification my car has to achieve this reading? Thanks for the info.[/QUOTE]

All you need is the proper year wheel/pressure sensors installed in your rims and the magnetic sensor activator.

Mark