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  #1  
Old 06-04-2000, 10:22 PM
V10nacuda V10nacuda is offline
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Question

Ok, normally I leave the light after loading the chiassis against the converter, about 2500 rpm. my 60' has been 1.77 & as low as 1.72. A buddie of mine suggested leaving at idle. So I did & the car cut a 1.70 60'. Does launching in this manner any harder on PARTS than my usual launch technique.

Thanks
V10

The car is 3900# w/me. 440, 391 gear, 26x 8.5in slicks. 12.30-.40 all day. The converter is TCI 10" Street fighter.

Any suggestions on converter upgrade??????
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  #2  
Old 06-05-2000, 03:51 AM
toolman toolman is offline
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Just for the record, I have a b-body SS springs, pinion snubber, slicks ,3500 stall. I had staged at low idle, and didn't preload. Then I punched it, I spun my slicks, mind you this track has a slippery starting line, but still launched hard. After 6 runs, my new rear u-joints lost a cup for some reason and broke the tailshaft on my trans, or vise-versa. Of course I'll never know since the trans is from GER and turned out to be just a street, low performance piece of crap. Next time, I'm going to try your old technique and see what happens. Oh, and a C&S trans. Hopefully it was a fluke, or the cheap trans. I think though that in the 60's they used to launch at high rpm in netral and slam it into gear. They were 10 second cars. I really wouldn't worry with your setup. But I would have a driveshaft loop anyway just in case. Just racing is hard on parts, but if I had your money, I'd go for it!!! (Anyone with a V10 in a Cuda has to have money right?) Besides when you break something, that just means it wasn't good enough in the first place, so next time you have an excuse to make it even better! Good luck and Put the pedal to the Metal!!!
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  #3  
Old 06-05-2000, 09:02 PM
V10nacuda V10nacuda is offline
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Toolman,
I guess I'll clear something up also. The cuda is a 440. I have a V10 2500 Truck. I wanted a screen name that covered them both. Hence V10 aNd A CUDA. I wish I had $$$$$ If I did the car would have a 572 B1 Motor!!! (dreams dreams got to have them)

Wow Neutral slams huh?? In a 10 sec car. I guess that would be a poor mans trans brake.

Let us know how it works out.
V10
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  #4  
Old 06-05-2000, 09:49 PM
Drag340 Drag340 is offline
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V10,

Normally this "flashing" the convertor will cause the car to hit the tires harder, which may or may not reduce 60 ft times, depending on available traction. Flashing the convertor on my dragster results in a 1.41 or 42, versus a normal 60 ft of 1.35 or 36, on the 2 step @ 4000 (4200 convertor).
My only concern would be ballooning or otherwise damaging the convertor.
My 2 cents........



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Mike
340" Front engine digger
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  #5  
Old 06-08-2000, 01:05 AM
ARIZONA ARIZONA is offline
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...DO NOT attempt a "neautral start" unless you want to replace a lot of drivetrain parts!!! I think what you are seeing with your car is a sign that the converter is not what it should be.
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  #6  
Old 06-08-2000, 03:23 AM
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Glen440 Glen440 is offline
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I always thought it was better to load up everything before you launched. I havn't tried launching from idle. I'll have to try it next time. I was loading my Tci 10" street fighter to 3500. Its actual stall of the line was 4000. The only thing that went wrong after 2 years of daily driver and 70 passes was the bushing in thetranny wore out and put a groove in the neck. The thrust bearing in the motor is still good. So they don't balloon too much. Usually you wear the thrust bearings out from loading up the converter if they ballon alot.
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  #7  
Old 06-08-2000, 04:40 PM
V10nacuda V10nacuda is offline
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Glenn,
How about trying that & posting your results. Post your gear, slick, & some engine info so I can compare, if ya could. I have the same converter...

Also post your LAUNCH Rpm.

Could someone explain BALLONING??

Thanks V10
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  #8  
Old 06-08-2000, 09:23 PM
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AZMOPAR AZMOPAR is offline
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Well ballooning is not something you want to have happen. The converter expands front to rear because the internal pressure exceeds the modulus of elasticity of the metal - kind of like blowing up a balloon. This causes obvious damage to the converter - and if severe enough will damage the trans by shoving the converter snout into the front pump. Another indication is if you can see the impression of the flex plate to crankshaft bolts on the engine side of the converter. Trans-brakes, NOS, and high stall loading the converter can cause this type of damage. The converter mfg can install anti-balloon plates on the coverter to prevent this type of damage. However, there is not a lot of room in the TF bellhousing area for an anti-balloon plate so they are not as effective as those for the PGs etc.
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  #9  
Old 06-08-2000, 10:57 PM
V10nacuda V10nacuda is offline
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AZ,
Thanks for the definition. Make sense... & wow that must be alot of pressure to do that!!!!!!
V10
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  #10  
Old 06-09-2000, 04:23 AM
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Glen440 Glen440 is offline
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I would like to post results next time I go to the track. The only thing is I don't use that converter anymore. I think it will cost alot to put a new neck on it. I also went from a 400 to a 440. My best times with the 400 and Tci Converter were 13.15's @104mph.
60' 1.84. 8-1 comp, 3.91 gears, 3900 with me,
sticky DOT tires. There is a chance I get it fixed to see if it makes the car any faster.
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  #11  
Old 06-11-2000, 09:49 PM
V10nacuda V10nacuda is offline
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WELL,
Just tried the new slicks, 28" tall. Old ones were 26". The weather was HOT & HUMID. Car ran 1.82-84 60'times until I got the things broke in. Got a by run in the first round & the car did it's best 60' time yet!!! .169!! Then idiot me RED's .498in the second round.

V10

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  • 98 V10 SB Q2wd.
  • MOPAR OR NO CAR!!!!
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  #12  
Old 06-12-2000, 02:52 AM
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Leigh Leigh is offline
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You creep, you weep. You snooze, you lose. That big red lights' gonna shine on yo' body every now and then! You should be happy, I STILL don't have my Dart ready to race. Put the pedal to the tin on the brake and see what expires when the button is released. Thats what my "freinds" want me to do. Nice freinds, huh?
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  #13  
Old 06-12-2000, 05:11 AM
Drag340 Drag340 is offline
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V10,

Was that red coupled to another good 60ft? Might have to lay off the light a little bit to compensate for the better hook. Remember, if ya don't go red once in a while, you aren't trying hard enough. Go get 'em next time!!!



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340" Front engine digger
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  #14  
Old 07-08-2000, 05:09 AM
Belvedere Belvedere is offline
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Finding the perfect launch rpm takes time. You need to make a change of 100 or 200 rpm incriments. It takes time but, sometimes 100 rpm too high or too low makes all the difference in the world. Keep an acurate log of each run and maybe make two runs at a particular rpm to back up your numbers. My car had a 4000 rpm converter, and it liked to leave at 3400. 3500+ would spin the tires and 3000 would not load the suspension enough for a good launch. The tires would lose traction about 6 to 10 feet off the line and spin again. Test and tune, test and tune.
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  #15  
Old 08-19-2000, 06:13 AM
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motorhead440 motorhead440 is offline
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my 70 duster runs 1.75 at 113mph, my 60' times are approx. 1.68 to 1.70 sec. I'm going to experiment this sunday with tire pressure and launch rpm. i've been running about 10 psi. i'm going to bump it up to 16 and see what happens. i run M/T e.t. street 28x11.5x15. (9") cheaters. I'll let you know what happens sunday evening. motor

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  #16  
Old 08-19-2000, 06:57 PM
Clonestocker Clonestocker is offline
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V10, I like the leave at under 2000 method, this allows the suspension to work for you.I use superstock springs w/no snubber. The snubber seemed to help unload the rear tires. My 360 Duster runs 11.60's @ 113 at 3000 ft. It's 60 ft times are consistant 1.58-.59 w/ it's best a 1.56. Good Luck Matt S.
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  #17  
Old 08-19-2000, 07:12 PM
rat roaster rat roaster is offline
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I ballooned a cheap converter a few years ago . The reason was more from heat ,I did a bunch of hot laps . The converter got hot and the metal streched enough from the torque of the big 440 that the thrust washer fell out . When this happened the converter got real lose (soggy) ,the mph & et dropped and the tranny oil got real hot real fast.Another good reason to have a tranny temp gauge. I ended up buying a Neal Chance race converter with anti ballooning plates and rebuilding the tranny.This converter is the same size as a normal converter only on the front where the hub is welded to the converter the metal is really thick (about in a 4" diameter) and on the back of the converter the metal is thick ( about a 4" diameter). I have had no trouble with this converter 10" 3800 stall it will flash to 4000 . I pre load it to 2000 and run into it with all the engines got. Best 60 ft 1.63 . I street drive this car and the tranny temp is ok . The cheap converter over heated the oil.I believe in converters you pay for what you get.Check out the converter on the bottom of their home page look at where the hub is welded on ,that is where the thick metal is.

http://www.mspmall.com/chance/

[This message has been edited by rat roaster (edited August 19, 2000).]

[This message has been edited by rat roaster (edited August 19, 2000).]

[This message has been edited by rat roaster (edited August 19, 2000).]

[This message has been edited by rat roaster (edited August 19, 2000).]

[This message has been edited by rat roaster (edited August 19, 2000).]
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  #18  
Old 08-21-2000, 07:54 AM
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motorhead440 motorhead440 is offline
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HERE'S MY RESULTS FROM THIS SUNDAY, I INFLATED THE TIRES TO 16 PSI AND LAUNCHED AT 2500, I RAN A BEST E.T. OF 11.67, 1.66 60 FT, 114.21 MPH. #2(hotlap) SAME LAUNCH RPM, 11.66, 1.63 60 FT, SAME MPH R.T. WAS .602 AND .542 RESPECTIVELY. I DROPPED THE TIRE PRESSURE TO 13 PSI, MY 60 FT STAYED AT 1.63, E.T. 11.69, MPH DROPPED TO 113.06. MY ELECTRIC FAN QUIT LATER SO IT WAS DIFFICULT TO KEEP TEMP AT 180 THE REST OF DAY, ALTHOUGH IT NEVER WENT SLOWER THAN 11.77. I GOT A BIT GREEDY AND STARTED RED LIGHTING IN THE FINALS. MY FINAL THOUGHT, I WILL PROBABLY BUMP THE TIRE PRESSURE BACK UP IF THE WEATHER CONDITIONS ARE ABOUT THE SAME. I HOPE THIS INFO HELPS ANYONE EXPERIMENTING WITH LAUNCHING, 60 FT TIMES ECT... MOTOR

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