this morning on the way to work (3:00AM, i hate my job) my car was pullin fast as hell (for a near-stock 3.1L that is). it does this every now and then, i guess every now and then i get a glimpse of the power the car SHOULD have. well a TomP tuneup is defnitely in order as soon as i get my next paycheck and weekend. i've had the car for over a year and haven't done a tune-up, and i'm damn sure the previous owner didn't do it either. my car's just beggin for it!

my new hood should be here in a couple days so i'll get some pics up soon. oh yeah, i got offered $4000 for my car today at a gas station, and i gave the guy my number, so it may be leaving me though. rest assured though, if i sell it, i'll own another camaro in under a week! well that's it, just lettin yall know what was going on (if any of you cared)...later..

 

my car used to do that, only when it was cold, it would pull really hard early in the morining in october... once it warmed up it tamed down a bit, i think it might have been my oxygen sensor though

 

colder air makes more power... so early in the day or at late night
youll see more power............. try it on a really cold day here in wisconsin and youll say why cant my car go like that all the time...

 

Kinda funny......I could offer the scientific explanations like Omar about the cold air, and about since the engine is cold, the air being pulled in remains cold and blah blah...but since the oil is so cold and thick as well (which equals extra force required to move it around and added friction), doesn't seem to make sense how much power you see on a cold engine does it??

On my 5.0...it's night and day. On a warm engine (and warm to me is only about 165 or so due to the thermostat and manual flexfan), it has difficulty spinning the tires without much effort due to a bad set of stock heads and a slipping tranny. On a cold engine, it will light both tires up at about 1/3 pedal, and haul nuts down the street like you wouldn't believe for not even being on it completely. I swear once it warms up, it loses about 50 hp.

 

I'm up at 3 AM becuase my 2 year old doesn't want to sleep!

 

the reason the car pulls like a 350 when its cold is because of the cold injector, it sprays extra fuel in cold start up thus the power increase

 

my old malibu was carbed and when it was cold outside it felt like
it had 20 more hp. so i dont know about the cold start injector thing................

 

Plus he has a 3.1. 3.1's have no cold start injector.

 

when a motor is cold, it doesn't run as well. The computer adds fuel so it'll run well and idle semi-smooth. The computer just takes the standard fuel mixture for the amount of throttle, and adds fuel depending on engine temp when it's cold. Once the engine warms up and the O2 sensor starts registering, the engine goes into emmisions/economy mode and keeps the air fuel as close to 14.7:1 as possible. The reason a carb'ed engine does that is because it has a choke on it that basiaclly raises the Air/Fuel ratio. Scientific enough for you guys?

 

I already knew this, but I'm still wondering why it runs SO much quicker when it's cold. When it's cold, it should be running slightly towards the rich side....and as we both know, rich, just like lean, isn't any extra power!

 

because it is raising the A/F mixture to what is closer to perfect for power...not complete combustion. It only raises it to like 15:1 or so, not enough to rob you of power, but when combined with the denser air charge(not heated my the engine block/intake manifold) it makes for MORE POWER!!!![insert evil laugh here]:rockon:

 

well,what it can be,i highly doubt it,but it happens alot w/ our cranks, the crank breaks right at a casting point,so sometimes it runs good and sometiems it runs like ***. ud think a snapped crank would b a bigger deal,but w/ the lil v6's.. my teacher was tellin us about it today in engines class. and h's not a moron,the guy builds nitro cars"he's helpin me w/ my 383" he has like 6 world records,its insane.

 

I think the next time I go to the drag strip...I'm going to see just how big of a deal the heat soak in the upper manifold is.... I'm bring me 3 big old McDonalds bags of ice!!

 

As far as the crank goes.....if the crank was actually broken...then the car shouldnt really run at all because the piece of crank behind the break in the motor shouldn't spin! Or so I would think! I'm thinking he meant it microfractures or gets small splits or cracks or something.... Which still sounds funny to me because quality controls for engines, despite the fact that aftermarket ones are far better, are still fairly precise!

 

ok, here's somthing I just thought of. Engine gets older and the cylinder actaully gets a little bigger because of friction...nothing you can do about that. When the block is cold, the cylinders are smaller and the rings seal better, giving you better compression and more power when combined with the cooler A/F mixture. When the engine heats up, the block expands ever so slightly, the rings don't seal as well and you don't have the extra fuel, making the car slower in general...wow, I could go on for days on the little things that probably don't make that big a difference.

Better theory...when you drive at like 3:00 in the morning, the paint hasn't soaked up as many UV rays, therefore making it lighter, right???:sillylol: With the Power:Weight ratio reduced your car goes faster.

 

see part of the problem is most of u are from warm states..
colder air is more dense and produces more power thats why all of u put ram air,cold air, intakes in......... what im saying is, i know its not good for your engine but i have done it before.
start my car when its 30 degrees out and stomp the **** out of it
then u say to yourself where did this xtra power come from.
then i have done the same thing on a 95 degree day and it is not as fast at all, as a 30 degree day here in wisconsin.. i dont drive my bird in the winter here.. im telling u this on experience..
i lived in florida for 5 years and ancorage alaska for 1 1/2 years
iron mountain michigan for 1 year.. im 31 all of the beating on cars trucks and motorcycles have been done when i was a
reckless teen.......... cold air more dense. hot air less dense.
1 pound of steak, 1 pound of fat... fat takes up more space, more dense.... they both weigh a pound but the fat is a bigger pile.
think of it as hot and cold air ,more air more power per volume.

just my 2and 1/2 cents: