what RPM at Launch

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69340

69340

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I haven't drag raced at a track in many years. Plan on taking my Dart to old time drags this summer. I am running 340 .020 over , trw 11/1 pistons, 318 truck crank, stock x heads, comp 480 cam, A-833 4 speed, 323 gear. m/t street radial drag tires. What do you guys launch your cars at plan on shifting at 6500 rpm. What times do you think i can pull with this combo.
 
It's difficult to predict ETs because there are so many variables. A couple of our customers run similar combinations. Both these cars routinely run 13.50 to 14.00 ETs. As they say, "Your mileage may vary."

A couple of suggestions though. Launch RPM will depend on what your clutch and tires can handle. Start out around 2200 rpm and adjust accordingly. And stay away from 6500 rpm shifts. Without head work and more cam, your combination is gasping for air and making little power above 5500 rpm.
 
I would think hi 12s I have a trans brake and leave the line at 2500 rpm just to be on the safe side, I dont need a broken pinion .different engine and combo than yours but a trans brake is kinda like a 4 speed at launch.
 
I usually launch my 416 stroker duster at 2600-2800 foot braking..
 
I agree with torquehouse. Start out low and work your way up. With my combo with slicks I lauch between 5800 and 6000.

Fred B
 
fred, thats one heck of a launch rpm haha careful ya dont leave the broken pinion and case behind or bust a u joint,haha If I tried that with my big block That 8 3/4 pinion would fly thru the case lol
 
mopar1962 said:
fred, thats one heck of a launch rpm haha careful ya dont leave the broken pinion and case behind or bust a u joint,haha If I tried that with my big block That 8 3/4 pinion would fly thru the case lol
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Hate to say it but that might be neat to see in person:toothy10:
 
mopar1962 said:
fred, thats one heck of a launch rpm haha careful ya dont leave the broken pinion and case behind or bust a u joint,haha If I tried that with my big block That 8 3/4 pinion would fly thru the case lol
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I have a Dana 60 so I hope that doesn't happen. My 340 bogs at any lower RPM. With street tires I can lower that down to 3500. I just keep my fingers crossed each time I let the clutch out lol

Fred B
 
I'd say it depends on your traction. With 3.23 gears and good traction you might kill or bog real hard off the line launching at a lower rpm. I knew a guy with a mustang who ran new slicks and had to launch a couple thousand rpms higher so it wouldn't stall. Most of my buddies dont have slicks and dont launch too high maybe 2000-2500 to keep the wheel spin down. I'd say 2500-3000 if you're really wanting to get the lowest et, but if your worried about breaking stuff maybe 2000-2500 might be safer. good luck.
 
your lucky, I need a dana. would like to go into the 9s again but have with the unbraced 8 3/4 ,ive seen the carnage of a broken pinion and case. seeing is one thing paying for the parts to fix it sux df, haha take care
 
sorry, missed the 3.23 gear .I still wouldnt launch over 3500 4000 max
 
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