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Discussion Starter · #1 ·
As I posted elsewhere:

March 20, Cecil County, Maryland, Junkyard 350 with 240K miles
13.86 @ 99.7 MPH
1.85 best 60 ft time
Weather and track conditions: near perfect

June 6, Island Dragway, New Jersey, Junkyard 350 with 240K miles
14.56 @ 92.7 MPH
1.93 best 60 ft time
Weather was humid (rainy all morning)but track conditions were excellent

I mean, I KNEW I wouldn't run as well because of the warmer, muggier, humid weather but SEVEN tenths slower and SEVEN miles per hour slower?

WOW! I may run a 19.1 @ 72 MPH in Vegas at this rate! No one else seemed to have as big a drop off as I did, I know the bone stock motors are affected more but this was ridiculous.
 
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Discussion Starter · #2 ·
Originally posted by Big Kahuna 13:
As I posted elsewhere:

March 20, Cecil County, Maryland, Junkyard 350 with 240K miles
13.86 @ 99.7 MPH
1.85 best 60 ft time
Weather and track conditions: near perfect

June 6, Island Dragway, New Jersey, Junkyard 350 with 240K miles
14.56 @ 92.7 MPH
1.93 best 60 ft time
Weather was humid (rainy all morning)but track conditions were excellent

I mean, I KNEW I wouldn't run as well because of the warmer, muggier, humid weather but SEVEN tenths slower and SEVEN miles per hour slower?

WOW! I may run a 19.1 @ 72 MPH in Vegas at this rate! No one else seemed to have as big a drop off as I did, I know the bone stock motors are affected more but this was ridiculous.
You didn't put any mileage on the car between the runs? Weather can be a bitch, can't it :D The weather probably hurt you by 5 tenths and the 60ft by the rest.
 
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Discussion Starter · #3 ·
ahhhhh.. welcome to the wonderful world of DA Billy. 7 tenths isn't so bad... attribute 2 for the 60' and 5 for the weather. Seems reasonable to me. :D
 
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Discussion Starter · #5 ·
The whole problem is you went to island! Any drag strip that doesn't own it's return road( ask them they will tell you!) and whos pits are half grass/gravel&ashphalt mix, whos stand belong in a peewee league baseball field, and who has a dip in the right lane no less! Island track prep aint the best, as indicated by your 60ft times. Go to a real track like atco or e-town(and don't complain about the ricers) And stay away from long island dragway!
 
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Discussion Starter · #6 ·
Originally posted by eric9c1caprice:
The whole problem is you went to island! Any drag strip that doesn't own it's return road( ask them they will tell you!) and whos pits are half grass/gravel&ashphalt mix, whos stand belong in a peewee league baseball field, and who has a dip in the right lane no less! Island track prep aint the best, as indicated by your 60ft times. Go to a real track like atco or e-town(and don't complain about the ricers) And stay away from long island dragway!
That sounds like Hallsville Raceway in East Texas :D I've run my best ETs there.
 
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Discussion Starter · #7 ·
Billy DeBee, you know, it could be something as simple as ignition wires going bad or other such thing that is hard to notice.
I do think the weather was not all that bad.
But after looking at how consistant your car was in the round sheets, I don't know now.
I guess as you stated, cars closer to bone stock are very much more sensitive to weather.
But the DA was not bad at all that day.
I think the ARE heads and 845 cam that you put on the Nabil built motor are going to help with minimizing weather ET loss.

Oh, one thing I know, it's not the track. we know that they had the starting line groomed to perfection. I watched them groom it before each of our rounds. !!! Amazing staff.
NHRA Division 1 track of the year, (2003), Island Dragway.
Terry the manager told me they used a whole drum of VHT that day.
It would not have been better even at MIR.

Also, your 60' get's slower as the air gets worse so don't add that to the factoring above, (since you did not spin). The 60' is off due to weather. Good air = good 60' power, bad air = bad 60' power

Just my thoughts.
Karl
 
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Discussion Starter · #8 ·
BK:

Billy, I hear you. I ran:

13.56 @ 100.67
1.98 60'

... and 2 months later at the same track:

14.23 @ 96.76
2.15 60'

Hot car temp, higher air density (over 5000'!) and **** track prep is why I have not been back.

Karl said they used a barrel of VHT, Ch*$t they have not used a barrel in the 3 years the track has been opened out here.

See you in Vegas

Roger
 
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Discussion Starter · #9 ·
Hey Eric;
I have to agree with Karl, the Island peeps did an AMAZING job at prepping the track. No spinning whatsoever. Hard launches. Plus they were SO nice to us.
I have had the privilege of racing at about 10-12 different tracks up and down the east coast and this one wasn't so bad. As a matter of fact, I always feel E-Town has a relatively slippery starting line (I know many will disagree) but the point is, maybe you just had a bad experience at Island Dragway like I always seem to have at E-Town.
And hell, we have grass pits at quite a few tracks, 75-80 included. But we got there early enough where we all pitted on the pavement. Nice place, nice people. Probably location of The Big Kahuna Open / Gramby Motorsports Day 2 in August.
Anyway, back to the car. I just thought .7 was a LOT! I was expecting some 14.10's or 14.20's. My first practice run was a 14.60! I was like WTF!!!
 
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Discussion Starter · #10 ·
Originally posted by Karl Ellwein:
....Also, your 60' get's slower as the air gets worse so don't add that to the factoring above, (since you did not spin). The 60' is off due to weather. Good air = good 60' power, bad air = bad 60' power.....
True fact there.

Also, Bill, what kind of programming are you running? Is it possible that the higher IAT, and maybe higher coolant temp, is causing the PCM to pull timing? That can really compound the weather effect. Bryan's or Ed's programming usually takes care of those factors, but stock or HPP tuning is drastically affected by temperature.
Were you possibly getting burst knock retard, or even actual knock going to WOT at the start line? If so, the PCM wound pull about 7 deg of timing and it doesn't let it back in until it's too late in the run. Any data logs for us to look at?

I've seen a maximum .4 sec spread from NA runs on a near-perfect Autumn day to a high 80's muggy day. If it weren't for the program tweaks from Bryan to eliminate the variables like I mentioned above, I could easily see another couple of tenths.
 
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Discussion Starter · #11 ·
Pat, thanks for the reply.

I have Bryan's programming, have had the programming since we dropped that junker in. I also had no knock, no detonation, it felt ok, just no top end at all.

I just thought of ONE thing that I changed, although it should have HELPED and not HURT.

I thought I had a 160 thermostat in there, but it either wasn't a 160 or it wasn't working correctly. In Cecil my temp gauge (it's a 95) was about 3/8 of the way up. Now, even though the weather is warmer, my temp gauge barely moves up. At Island that temp gauge barely got over the line, even when I let her idle for a while.

Anyone think that could make a difference? Especially a NEGATIVE difference!
 
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Discussion Starter · #12 ·
I've still got Gravel embedded in my knees from the last time I was at Island Dragway and changed from my streets to my slicks :rolleyes: (1999)
 
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Discussion Starter · #13 ·
Us nitrous guys dont have to worry about DA and humidity as much as you supercharged guys..

We bring the weather with us in our trunks..

EDIT you dont have a blower on that car.

But my car has ran as fast as 12.0's in the winter @ 112mph and as crappy as 12.9's @105 with just a tempature difference. On motor of course fellas..
 
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Discussion Starter · #14 ·
How do your 1/8 mile times and mph compare?
If they're not off as badly as the 1/4 times, it could point to a partially plugged fuel filter or a pump starting to go south. You might want to put a gage on and watch it under a mock 1/4 mile run on the road just to eliminate that possibility.

Pat
 
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Discussion Starter · #15 ·
Pat;
Looks like my 1/8 mile times are blowing donkey dong too, although I will let you seasoned racers let me know if I know what I am looking at:

March 20:
1. 60ft / 330' / 1/8 / 1/8 MPH / 1000' / 1/4 / 1/4 MPH
1. 1.852 / 5.612 / 8.800 / 76.99 / 11.544 / 13.865 / 99.67
2. 1.867 / 5.630 / 8.826 / 76.70 / 11.584 / 13.913 / 99.37
3. 1.883 / 5.665 / 8.848 / 76.67 / 11.616 / 13.944 / 97.17
4. 1.885 / 5.664 / 8.860 / 76.75 / 11.616 / 13.946 / 99.27

June 6:
1. 1.964 / 5.936 / 9.251 / 73.85 / 12.143 / 14.563 / 92.89
2. 1.941 / 5.919 / 9.240 / 73.77 / 12.138 / 14.565 / 92.63
3. 1.936 / 5.919 / 9.238 / 73.66 / 12.126 / 14.563 / 92.53
4. 1.989 / 5.967 / 9.284 / 73.79 / 12.179 / 14.601 / 92.83

Basically, it looks like I was losing .5 on the 1/8 times.

Any ideas? I was, as you can see, real consistent and went to the final 3 racers. But man it felt like I was driving in quicksand! I was asking around the pits to see if everyone else was 'off' by that much and while everyone was a bit slower, no one got affected like I did.

Thanks in advance.
 
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Discussion Starter · #17 ·
Originally posted by BowtieNut1:
Still no smoking gun.
I think you're gonna have to log some PCM data to figure it out.
Or drop in that 845 cammed, big flowing aluminum heads, LT1 with that new Edge converter I have sitting here!
 
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Discussion Starter · #20 ·
Bill,

My guess is your PCM timing. Do you have any way to make some data runs? If you're not getting any spark knock, you might think about advancing the timing a bit to build cylinder pressure in hot weather. On the other hand, you may be getting some spark knock and the computer is PULLING timing...
 
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