33IMP
Well-Known Member
Bill, what do you attribute the performance loss to, primarily? The added weight, or the induction mods? Or, just the combo of mods.. And were these passes on drag radials? If so, faster or slower than slicks?
On slicks. Same setup at previous race. Only changes was the hood and air cleaner. I absolutely believe the biggest factor to be weight however I could tell the car was down on power as well. I didn’t want to risk running without the air cleaner because of how close the carb is to the hood and despite the fact that I tried to clean it out as much as possible, what sentiments could be trapped in the 55 year old hood that could fall out and get ingested.Bill, what do you attribute the performance loss to, primarily? The added weight, or the induction mods? Or, just the combo of mods.. And were these passes on drag radials? If so, faster or slower than slicks?
How did I miss this? 10.50 @ 127 is my guess
( From a vision)
Bill told me what he ran yesterday lol .Better have your eyes checked. Lol
Weather changed tremendously between the first round of qualifying and the 10.50 pass. You can see the changes in the weather data that is posted along with those timeslips. Also the fact that I started the day with a full tank of fuel and never added any played a part, albeit not a huge amount.The bigger question is why is the car picking up so much? You started day at 10.68 and ended at 10.50. That's almost 2 tenths. Did the weather/wind change that much, traction issue?
Weather changed tremendously between the first round of qualifying and the 10.50 pass. You can see the changes in the weather data that is posted along with those timeslips. Also the fact that I started the day with a full tank of fuel and never added any played a part, albeit not a huge amount.
Temps, DA and water grains dropped quite a bit. With my car, water grains makes a big difference in how it runs.Did I miss something on those slips and weather data. Looked to me like the weather only changed 500 foot DA during the course of the day. From around 2200 to 1700. That is typically 2-4 numbers, maybe 5. Moving almost two tenths is a head scratcher. Never seen anything like that before.
Regards gas, even if you went through 5 gallons, that’s only 30 pounds or a hair more and because of where that weight is, that might not even show up on a slip. If I splash in a couple gallons at the track I don’t generally even account for it dialing the car. It’s a non factor to the ET.
I made 6 passes my previous outing one day,
weather stayed roughly the same, car went back and forth one number all day, with less gas each round obviously, and I never topped it up. 1/2 a dozen passes is maybe 4 gallons of fuel for me.
That's how you dial yourself out lolTemps, DA and water grains dropped quite a bit. With my car, water grains makes a big difference in how it runs.
Other than that, I have no explanation. The car always goes quicker later into the afternoon and night.
Temps, DA and water grains dropped quite a bit. With my car, water grains makes a big difference in how it runs.
Other than that, I have no explanation. The car always goes quicker later into the afternoon and night.
I just know if I had a car like that, arrests would be made. Trying to hold that back for some blinky light....not in my skillset.Funny guy. Care to wager?![]()
Keep in mind, I’ve made 75+ passes with an aero scoop fiberglass hood and 6” tall velocity stack style air cleaner. This was the first time running a flat steel hood with 3” drop base air cleaner so I have zero data to work with. It was an experiment that showed .15-.20 slower 1/4 mile times and if that’s not enough, it totally changed the way the car leaves. I finally got a handle on the car with the original setup and will be going back to it next time out. Flat hood will be put away for now.DA is only moderately related to temperature.
I have slowed down at night when it’s 70 out, compared to when it was 85 out in the middle of the day, just because of humidity and or dew point coming in.
Actually your DA didn’t drop much. Going from 2200 + DA to 1700 plus is only a very few numbers. That is actually a very stable race day.
I raced between 1500 and 2300 feet my first weekend out. Both days were actually completely different. Warm and clear. Dreary, cloudy and humid.
Car was between 6.56-6.60.
This weekend just finished I just got back from racing in Ohio. The heat was stifling. Car ran 6.66-6.68, but that was at 3600-4000 foot DA all weekend.
So basically probably a tenth and a half quarter mile but my DA went up 2500 feet, not 500 feet. I had a 10.48 1/4 mile hit, about 1.5 tenths off from good , not mineshaft air( under 1000 foot)
Think that is probably pretty typical. I don’t lean the car out for heat, or fatten it up( usually) for cool weather.
I am extremely curious to see what the scoop was worth...Keep in mind, I’ve made 75+ passes with an aero scoop fiberglass hood and 6” tall velocity stack style air cleaner. This was the first time running a flat steel hood with 3” drop base air cleaner so I have zero data to work with. It was an experiment that showed .15-.20 slower 1/4 mile times and if that’s not enough, it totally changed the way the car leaves. I finally got a handle on the car with the original setup and will be going back to it next time out. Flat hood will be put away for now.
I love the look for sure but the car is much happier with the scoop so it will be going back on.I like the new look but, of course it's going to hurt performance. It's probably frustrating to slow down but again I like to factor-in 'points for style'...Not sure it was considered a factor but if you're on the edge for timing then drawing underhood heat is going to hurt that's not quantified in the weather data.
Absolutely weight changed the way the car leaves. I think the scoop attributed to a little more power and mph but more importantly, consistency. With the scoop, I saw a maximum of .10 swing with extreme weather change but in only 3 passes, I saw .18 with the flat hood.I am extremely curious to see what the scoop was worth...
I would think the change in leaving the line would be more of a weight distribution thing, especially with a car as dialed in as that, but I really don't know.
Really? I figured you'd see wider variations with the scoop. That's nuts. I figured the scoop would add variables of wind speed, cross winds, external temperature fluctuations etc.Absolutely weight changed the way the car leaves. I think the scoop attributed to a little more power and mph but more importantly, consistency. With the scoop, I saw a maximum of .10 swing with extreme weather change but in only 3 passes, I saw .18 with the flat hood.
I think underhood temps played a big part in it. Car definitely got hotter with the flat hood.Really? I figured you'd see wider variations with the scoop. That's nuts. I figured the scoop would add variables of wind speed, cross winds, external temperature fluctuations etc.
Some things, I never would have guessed.
Really? I figured you'd see wider variations with the scoop. That's nuts. I figured the scoop would add variables of wind speed, cross winds, external temperature fluctuations etc.
Some things, I never would have guessed.
Keep in mind, I’ve made 75+ passes with an aero scoop fiberglass hood and 6” tall velocity stack style air cleaner. This was the first time running a flat steel hood with 3” drop base air cleaner so I have zero data to work with. It was an experiment that showed .15-.20 slower 1/4 mile times and if that’s not enough, it totally changed the way the car leaves. I finally got a handle on the car with the original setup and will be going back to it next time out. Flat hood will be put away for now.
I prefer the flat hood look for sure. Think I might get a flat fiberglass hood and try it without the air cleaner. Just need to play with it for a while and figure out what the car likes.I hear ya. I had a bolt on hemi Dart spare hood for my car when I bought it. Sold it 4 or 5 years back. Couldn’t bring myself to further molest my sleeper look.
In hindsight, would have been fun to try it.lol