I was out cruising alot yesterday evening and my car was running great like always. Temperature was about 70 degrees yesterday here in Ohio. This morning I get the car out to drive to work and she starts fine on my 10 mile journey to work. Then I decided to play around alittle and she has a very bad bog and shutter for a few seconds and then picks up and goes. The temperature this morning was in the 40's. I got all the way to work and the thermostat said 180 degrees and the car was still bogging and falling on its face. What does cooler weather really do to my tuning. Does it make it richer or leaner? I know all the cars at the track run better as it gets cooler but my car would be embarrassing if I tried to run it at the track in cold weather. I have just the flat hood on my car. By the way, my car ran its first 12 second past two weeks ago in 65 degree weather so i know it is or was tuned great. Any help would be great.

Thanks, Erik

cooler air = leaner mixture. It could be that your tune is slightly lean, but OK, for the warm weather and too lean for the cool weather. Maybe try going up one jet size and see if it goes away.

If you have a choke on that carb it might need some fine tuning for cooler weaether. If you dont have a choke in the cooler morning air, it will run like crap until its fully warmed up. But if its warmed up fully and still bogs, then gheatly's suggestions are in order.
graemlins/thumbsup.gif

Would jet up the primaries or the secondaries? Prbably do both I would assume. Its funny if it a lean condition because yesterday when i was messing around and cleaning the chrome I pulled a spark plug and noticed it was alittle darker then last year which would be a rich condition. i turned the timing down yesterday 2 degrees too. i am not sure if this would result in a lean codition or not. i will drive it home today in 78 degree weather and see what happens. i am sure it just has to do with the coller weather. 30 degrees in one day is a big difference.

Erik,
I live in Colorado so it is not uncommon for us to swing up to 50 degrees hotter/colder in one day! During the summer, the mornings are typically around 60-65 degrees and the highs are in the 90's. I love it and the car likes the cooler mornings also as I can even feel a seat-of-the-pants difference from my morning to afternoon commutes.

Like gheatly said tho, if you are running slightly lean normally, then the cooler air will make a difference. Sounds like you might fit that OR, sounds like maybe the choke is opening too fast possibly? If it opens too quick before the car warms up some, that can cause problems also.

FYI, you only need to jet up the primaries if that's the case, the secondaries should not effect anything but WOT or heavy throttle.

good luck,
Bill C.

Thanks Bill, that seems to be the concensus from everybody. This actually happens when I get on it so it very well could be the secondaries too. I will be in Colorado in september hunting, can't drive the camaro though, need a place to bring back my elk. Thanks again, i will try jet it up tonight and see what happens.

I have a manual choke on mine and I always leave it open. If you have one leave it open and see what the difference would be. What kind of motor oil are you using. My car does this when I use thick oil or it's time for an oil change. I guess for some reason it doesn't circulate well in the cold. If I warm it up for around 10min before I leave it works fine. But any less than that and it dies on the road when I stomp on it.