Dane@LGmotorsports

jbsblownc5

All Bolt ons...

I did 2 passes at the Magnum mile this year before it got shut down, 201.4 and 200.7 MPH.

Chonger

Holy crap does your car rip.......................

jbsblownc5

Thanks, It sure is a blast to drive...

robbieroflcopter

I would think that a stock stage 1 car would do 200 with enough road at sea level. I got 196 (and still climbing, ran out of road) at 5000 altitude with just a tune and halltech.

Mikec7z

while sea level provides more power typically with most cars via more oxygen to the chamber, the way these cars computers work, they cause the cars to run more and more rich to keep the power in check.

Meanwhile, the thicker air slows the car down due to more drag on the exterior of the car.

I believe these cars with a stock tune are faster top speed at high altitudes, vs at sea level.

I have not done a test myself yet, but that has been my observation on this forum so far.

6Speeder

I don't think that's correct. At altitude there just isn't enough oxygen to make good power.

Mikec7z

correct, but the cars have a limit, known as p0106, so at altitude, the car can be brought back UP to the 650hp mark via haltech/bms, and proted TB, catless x pipes, pulley, etc.

Meanwhile, cars at sea level, these upgrades cant be added without hitting p0106 much sooner, and as the cars are approaching that air flow limit, they are already making decisions to run richer and richer.

on the stock tune, all cars have a HP limit due to the p0106 code. We have big threads about this already.

So the only variable that changes between cars at altitude and cars at sea level, is the drag on the body of the vehicle.

Highest top speed stock TUNE z's I have seen are all at high altitudes. (yes, they have aftermarket parts, but stock tune is the key variable. Those same upgrade parts ruin things on cars at sea level and throw the p0106 code on the stock tune)

edit, and the 150mph limp mode i was referring to was also code p228c, but we were not far enough into our lemon law cases to disclose that we were the guys about to lemon our cars for p228c, so we kept it secret and focused on the other limp mode code at 150mph, p0106... so when we say there is an "airflow limit" in this post, the logic behind it is, since there is a fuel flow limit of the stock pump, and since the car matches air flow with fuel flow, there is still a limit to the cars.

And since one can pulley back up to that flow limit on a high altitude car, then the high altitude cars will be faster since they have less air to cut through with their bodies.... so less drag on the car itself.

3 Z06ZR1

I do not believe that for one second nor do most of the many who actually have mods on these cars on stock tunes. Explain over 600 rwhp on the stock tune on a dyno?
Happens all the time! That is over 650 crank???
You may have big threads on it, but you have big threads on many things doesn't mean they are right! But then you have become the forum expert on every subject posted.
Some threads and theory's, stuff I hear are more baloney than Oscar Meyer! Then of course anyone GM, Tuners, vendors , included are all irritating to the superior mind like yours!

Mikec7z

i agree the limit may not be right at 650, im not arguing against the idea that it is higher... but there is a p0106 limit on all the stock tune vehicles, and that is an airflow/air pressure limit of air after the screws, coming into the engine.

Simple physics, one limits that, they limit the power. All stock tune cars have that limit. All stock tune cars take deliberate actions to run more and more rich as they approach that limit. Running rich limits power.

My main overall point i will argue is that a stock tune z06 with upgrades, staying under the p0106 code, but getting close to it... that car will have a higher top speed at high altitude, than another stock z staying below the p0106 air flow limit, while at sea level.

And since we are talking top speed, and the person i was responding to said "stock stage 1 vehicle", then p0106 and limp mode are absolutely relevant to the convo

Warp Factor

Lots of tuners and dyno operators make their money on spitting out better numbers after mods or tuning, than before. There are lots of ways to do this. Some may be real power increases, and others may not. Maybe you got rooked, or maybe you didn't.

Mikec7z

exactly, and notice NONE of them have countered me yet in all of my posts about there being an airflow and thus power limit...

..nor do any of the savvy vendors of aftermarket products counter us.

They know the limit is there on the stock tunes, but discussing it prohibits them from selling as many goods if they advertise this knowledge to the public. And that's why none of them pipe up to cross us on this, they know we are right, and they know crossing us will only result in a FAIR test and logical discussion.

Limit to air pressure and/or air flow... limit to power. Very simple.

Run rich as that limit is approached... limit to power.

Plenty of dyno's show these cars afr go from 12.4 down to 10.8 midway through the pull while at WOT. That RPM the afr dives to 10.8 CHANGES which RPM it occurs, depending on what mods are added to the car. The more mods to flow more air, the sooner it dives rich in the RPM scale to limit power. Running rich limits power. All 101 basic concepts.

6Speeder

Still you aren't seeing just how much power you lose at altitude. Consider MY 2015 Z07/Z07. I dyno at the same dyno, a dynojet, stock and after every mod to see how much if any they help. I am still running the factory tune. Stock it made 579 SAE RWHP (that's corrected to sea level.) BUT, uncorrected, at about 6,000 feet altitude it ACTUALLY made only 488 uncorrected RWHP. That's a 90 rwhp difference I'd have to gain with mods on the stock tune. I added a Halltech, a Mamo ported throttle body, gutted the rear cats, AND added an IW 9% overdrive pulley. My dyno results (same dyno, similar conditions) made 651 SAE RWHP, but in reality, because of altitude only made 524 uncorrected RWHP. That still (with all those mods) leaves me 56 RWHP short of a stock car at sea level. There is no way I am going to go faster with a 56 RWHP deficit. Not gonna happen. I have since added the main cat delete pipes but haven't dyno'd since. The best these have gained me is MAYBE 15 RWHP. There's the math, and I believe I've pushed the limit of the stock tune, because she's running a bit leaner than stock and I don't want to blow her up. Soon I will dyno for the results of the cat delete pipes , then I'll tune her.

6Speeder

Now, as to your claim that you can go faster in thin air, how a bout a real world test. My friend has a Tesla P100 (stupid fast car), and we postulated that it would quarter mile quicker/faster than one at sea level because it isn't dependent on oxygen content. Guess what, it ran similar times here in the summer where the DA was over 8,000 feet to what they run at sea level. No gain due to thinner air at altitude.

robbieroflcopter

IMHO, I don't think the less-dense air is going to make up for the 15% power loss I experience due to altitude. My car maybe makes stock hp at altitude now with tune, xpipe, intake and 15 pulley. And that's a big maybe.

Mikec7z

You are misunderstanding me it seems. After the screws is a map sensor. That sensor reads a lower reading at higher altitude since the air is thinner. However, with just a few mods, it is possible to bring that pressure back up to equal at the map, as the map sees at sea level. The map has a LIMIT it is allowed to see... p0106. Once that limit is exceeded, the car goes into limp mode.

I can put a smaller pulley on a car at altitude and get it back up to 650hp.

I cant put a smaller pulley on a car at sea level because the car will instantly hit the map limit, and throw the code p0106.

I have to spin the screw faster at high altitude to make equal map as we do at sea level... but... equal map pressure CAN be made after the screws with a few mods, and the stock tune will allow for these mods at altitude... the stock tune wont allow for as severe mods at sea level. This is due to the map sensor throwing the car into limp mode when the map pressure limit is reached.

Once MAP after the screws is the same, power is the same. Again, we had a huge thread about this, many people tried to argue, at the end of the day, everyone, after many math equations and physics theory explanations... everyone agreed that equal map pressure is equal HP at the wheels, so long as the pressurized air is the same temp in both manifolds. (it does get a little hotter on the screws that had to spin faster to get to the same map)

Once both cars have equal power, then the thinner air allows a car to go faster, its already been proven on this forum, people have posted videos of near 200mph with stock tunes at high altitudes, and the guys at low altitude can't really break 190.

I have a stage 1 car, i am at sea level, my car is right up to the p0106 limit... i cant move anymore air or make anymore power... i am limited around the low 190s due to air resistance. Cars at altitude get to 200 basically, with the same stock tune and aero.

3 Z06ZR1

Same old bag of crap you always reach in to! Dyno's operators fudging numbers! Trying to support the village idiot while sounding like one!

6Speeder

I understand you perfectly. The problem is in your reasoning is your thinking "I can put a smaller pulley on a car at altitude and get it back up to 650hp". No you can't, not with the stock tune. The effect of less oxygen at altitude is too great to overcome with this small blower and the stock tune. I'm already running a 9% overdrive pulley and more mods and am still down 56 rwhp from stock at sea level. I could go with a larger overdrive pulley but will have excessive rpm, and will be operating the blower out of it's efficiency range and will be producing heat, not horsepower. And, the stock tune is producing a leaner than desired A/F already with a pulley and mods. With more boost it will go even leaner and probably Adios Muchachos. And, thinner air did not allow an electric car to go faster or quicker, even at 7,000 effective altitude.

What you're posting is your unproven theory. What I have posted is fact with the numbers to back it up.

Mikec7z

And there is a very long thread that says I am right and you are incorrect.

So we will leave it at.. you and i disagree.

The oxygen ratio in the air at altitude is the same RATIO to other gasses as it is at lower altitude. It is just spread out. So less molecules per volume... Because it is low pressure.. but once it is pressurized to the same pressure, it is the same oxygen content as it would be anywhere else.

ONCE the air is pressurized to the same pressure in the manifold, it has the same amount of oxygen molecules per volume as it would at sea level.

20psi true bar map pressure behind the screws, is 20psi bar pressure behind the screws. Doesn't matter if the car is in space hooked up to an air tank, or if its at the bottom of the ocean... 20psi true bar pressure in the manifold after the screws is exactly that... it matters not what the outside world is up to at that point.

You aren't the first one to pose the EXACT argument that others did, and all I can tell you is, all of those people eventually folded. I'm not going to get into it again, i've already written novels having to explain this to people in the past, as have others. I'll bet money i'm right, and its easy to test. Bar pressure at the map sensor is bar pressure at the map sensor. Dyno will measure the rear wheel HP... the only loss, is that it takes a bit more power to spin the blower screws faster, so TECHNICALLY the higher altitude car makes SLIGHTLY less power with same map bar pressure and same temp of air.

but other than that, the info that you are reading saying the oxygen content is less... yes... when it IS at lower bar pressure, but once it is pressurized to the same apples to apples bar pressure in the manifold after the screws, it is the same oxygen content. I'm very solid in my understanding on this topic, its been debated heavily before.

Mikec7z

as far as your comment about the stock tune... the tune knows NOT what the blower rpm is, all the tune knows is absolute MAP bar pressure after the screws, and that pressurized air's temperature. The tune has the same max map pressure threshold programmed into its computer, whether it is on mars, on top of mount Olympus, or at the bottom of the worlds deepest mine...

The car's computer does not change its max map pressure setting based on where the car is.

Equal map max reading, means equal o2 content in the manifold. (as long as iat are equal)

The stock tune accepts anything UP UNTIL the p0106 limit is reached, then it puts cars into limp mode.

And as far as running lean? Nah, they run richer and richer as they approach the p0106 limit.

They go from reading a 12.4 afr down to a 10.8 afr when they are about to hit the p0106 limit. The car adds additional fuel to the tune as the map limit is approached.

If you find yourself running leaner than other cars, its because you don't have as high of a map reading as they do... once you do.. the car will have a 10.8 afr.

And as for your statement saying i have no figures? Look at the afr graph of every stock tune c7z in the world... and you will see exactly what im describing, car goes from 12.4 afr and then dives to 10.8 like clockwork on the afr, around 4000rpm, but the exact rpm number varies depending on how soon the car is reaching the map limit during the dyno pull. The more map pressure, the sooner the car dives to 10.8 in the rev range.

If the wideband 02 sensor is sniffing at the back of the exhaust... then it will be slightly different number values, but the same concept... a dive into the rich zone sooner and sooner in the rpm range the more mods you put on the car to create more map pressure sooner in the rev range, behind the screws.

And if you have dynos of stock tune cars that show otherwise, please post them, im always looking for anomalies