Posts: 2045
Joined: 5/22/2003 From: Newport News, Va Status: offline
Ok i was thinking about this the other day, after reading a letter from a reader of MM&FF in the latest issue, asking about 1/4 mile times based on trap speeds. he had traction problems like i have. i pulled 93-95 mph trap speeds consistently, despite horrible traction and launching problems, ( i also think my chattering flywheel problem affected my launches) i managed to pull these with terrible high 8 second 1/8 times, on my way to low and mid 15's. i have a friend with an 02 GT with just intake and cat back, shifter and springs who ran high 15's doing as i did, but finally figuring out how to launch with street tires he pulled a 13.8. assuming i can figure out how to hold her down on street tires, or throw on some drag radials, what should my 1/ times be? besides whats in my sig i have a 5 spd TKO/ BFG G force 275/45/ZR17's.
Posts: 90
Joined: 5/12/2003 From: United States Status: offline
So BCisme, your trap speed is really a measure of your engine HP output. ET is a really a measure of your traction efficiency. A lot of factors are involved making a calculation from ET to mph or vice versa very hard to do. What were your 60' times? It's your I1 time on the timeslip. That will tell you if you've left some ET on the table or not. My mph doesn't vary much at all even if I spin the tires or not. But ET can dramatically change. With your set up the 275's should hook decently with a good burn out. The trick with a 5 speed is side stepping the clutch to get out of the hole quickly. That's a tough art to master with radials. That's the reason I'm running AOD with a stall converter. Much easier to launch.
Posts: 205
Joined: 7/17/2003 From: United States Status: offline
Theres no way too tell by those numbers. You have to really know how to plant them in order to get good times. Ive also noticed that added weight to the car, helmet, tools etc...really effect yer times. Just burning a quarter of a tank makes a difference in yer ETs. my .02
Posts: 797
Joined: 7/15/2003 From: United States Status: offline
93-95 mph, would suggest you have a low 14 or high 13 sec ride. But it would be a perfect launch no wheelspin and you would need a 2.1-1.9 60ft. Gears, tires, launch rpm, weight, shift points, and torque all play a part in getting you off the line. Not to mention huge variables like the track and weather. MPH doesnt change much, but ets can be all over the place. Simply think of it this way. It has a certain amount of distance to cover, if time doesnt matter, it will still accelerate to the same speed range over the same distance. How quickly you can get it moving is where the ET variance comes into play. When my 60 times change .1 I get a .2-.4 time difference at the end of the 1/4. Also my car is set up to run the 1/4 I have been getting 1.7's on my DR's and 1.6-1.5 on slicks. Its all in the launch as far as ET goes.
I like the automatic as they are consistont, you can't shift faster than a machine and thier easier on the drive line....love those transbrakes!!!!!!!!!!!!11vfast37832.6163541667
Posts: 205
Joined: 7/17/2003 From: United States Status: offline
My 5 ET is consistant as all hell. I dial in 14.4 and run consistant 14.41 to 14.53s. That was when I was stock. Now that I have a few mods, Im still tryin to work out a good launch so my ETs are all over the place. Its the driving that makes it consistant. Autos are just steering the car down the strip.
brock..remember it's all about winning rounds for the $$$$ it not sit and hang on..that;s those a-alter and 260-280 inch dragsters.. when I drove an automatic I never used any boxes ie delay boxes ..I wish they would do away with them and airshifters etc..and I would pull .05 .06 lights...
Posts: 797
Joined: 7/15/2003 From: United States Status: offline
I can do .008 reaction lights with a clutch, but havent quite figured it out with the auto yet. So I leave like its a 4 gear, and can usually get. 01-.04 from it.
man your guessing on the light,,glad it's working for ya...but for the novice guy auto is the way...my nova I run within a few 1000's...it a 67' nova 502 with a 6-71 on it run low 9's it's an 8 sec car but I don't need it as this car is driven on the street some...
Posts: 205
Joined: 7/17/2003 From: United States Status: offline
Hmmm....my best reaction was .502 in the bracket. I was told that was a perfect light, but I hear different things all over. I know when I pulled a .5 flat I red lighted, so my friend might have been right.
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