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Discussion Starter #1
I have made a lot of progress with my dart in the 60 ft department, but feel there is more there.
My car is a 3000 lb with driver 65 dodge dart, 106 inch wheelbase, 528 cube injected alcohol motor with a torqueflite, 4.56 gears, 33.6 x 15 x 15 goodyear 2079 slicks, run tubeless.
Converter is very loose, 6400+ stall, shift points 7100, best ET 8.779 at 153.16, 1.284 60ft on M/T drag radials, will go 8.80s on goodyear 33.6 x 15 supergas tires, run tubeless. I use a transbrake with a very low throttle setting for launch, leaving from 4000 to 5000 against the loose converter.
Frontrunners are 25 inch for short rollout.
Suspension is 30 inch ladderbars in back, anti-roll device, 68 inch solid wheeliebars, a arm front suspension with rack and pinion, afco double adjustable on all corners.
Springs are 350 lbs/in on front with a 2/1 ratio, 130 lbs inch in rear with mounts 5 inch behind axle centerline. Wieght distrubution is 50.5 percent rear. Crank centerline is 14.5 inchs above ground.
So far best progress has been with front travel limiters set at 3 inch, shocks in front at 2 1/4 turn sweeps of shaft from full loose for rebound, rears set at 2 1/2 sweeps for rebound, set at 4 for bump on rear.
Ladderbars are in the bottom hole, which puts them 5.9 inch off the ground, with a neutral line of 6.6 inch high at that point.
Best 60 ft to date is 1.272 in the bottom hole, 1.262 in the second hole from the bottom for the ladderbars. Car will pull the tires out of the beams much more vertically in the bottom hole, second hole is very inconsistant due to change in rollout depending on traction, moving the 60 fts by .02 back and forth depending on how it left the line, rolling out or coming out more vertically.
Even with tirespin car will wheelstand almost all runs, and the few times it tried to hook real hard it felt very violent, with an uncontrolable wheelstand(before the wheeliebars!) or hitting the wheelie bars so hard it unloads the rear tires.
I understand my front travel limiters may need some modification in order to make them a more progressive stop, like incorperating a soft bumper, and am going to do that this winter. Same for the wheeliebars, i will try and incorperate some form of rubber bumper or cushion in the bars to make the contact with the ground less violent which was so hard i could feel the tires unload when they hit.
Any other things i can do, or anything that needs changing in this combo? The two tracks i frequent the most are Brainerd international, and Rockfalls raceway, not noted for traction for regular events, But BIR can be good some weekends later in the year.
 

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your crankshaft c/l is pretty high for the hp you are making.generally as power goes up engine goes down.sounds like you are transfering weight too fast you need to slow that down.front shock rebound should be closer to full stiff.you may want to move some weight to the nose.you say your bars are solid.what tubing dia. and wall thickness?by the way that block i have is a six bolt alum.
 

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Discussion Starter #4
My wheelie bars are made out of what is left of some CE springloaded bars with the flat aluminum strap type bottoms. I modified them by replacing the bottom parts with longer round 1.25 x .095 mild steel tube, then i made up some solid spacers to replace the springs and extended the top bars by using the same type of tube, 1.25 X .095, which just happened to slide over the original tubes, then x braced the top tubes with 3/4 inch tube, and left the axle tube in place same as original to make it very rigid side to side.
I did some more measuring, and believe i have about 14 inch crank CL to ground dimensions, and that is as good as it will get, due to having a very expensive pan that is a bit deep. I will strongly consider moving some wieght, just have to figure out how.
On the mod motor block, i need the short deck 4.6 block, is that what you have? My saleen blower will only work with a 4.6 lowdeck style block.

 

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i had a customer this summer with the same problem.come to find his bars were 1- 1/4 .095 also.i would use 1-1/8 .065 for the uppers.this will give you a little more flex so you don't unload as soon as you hit the bars.run them at six inches off the ground to the center of the bolt.this should help alot.
 
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