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Discussion Starter #1
We are running a n/a 598 bbc in a stang at 3130 in weight, ran a 8.59-8.62 with 60" in the 1.29-1.30 every time. Car is hooking every pass, we started off with low rpm launch ( 3000rpm and went up to 55000 ) and it never really improved on et. just stayed the same every pass. Im running a wolfe adjustable coil on control arm set up with the racecraft adjustable lowers that are currently in the stock locations. Is this a good 60" foot time or should it be better? just looking for thoughts input, ideas, should we try something diffrent or leave it alone? more specs on chassis is-
-fox mustang
-coil over fronts 120lb springs
-bbc 1045 hp
-power glide
-4.10 gears
-315 drag radials
-3130weight
-single adjustable strange fronts and rears
here is a link to the video, at the end there is a slow motion launch


let me know what you guys think, thanks
 

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I would think a horsepower car would 60' better...my buddies SBC mustang with 400 less horsepower in a 300lb lighter car would 60' in the 1.26-1.28 area off the footbrake or the transbrake
 

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Discussion Starter #3
Thats why i put the post up, curious to what others are doing, and looking for input. thanks
 

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maybe its the video but it almost sounds like the car lays over just before the 60' beam could be a carb issue or it just might be the sound out of the video camera. it only seems noticable when you leave at the higher launch rpm thats why i say carb maybe.
 

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Discussion Starter #7
Its a 9" coan that flashes to 6300 and 1.60 first gear, thanks for the responses guys!
 

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You may not have enough low gear to get the car moving quickly..

What is the RPM you are wanting the engine to run out the back?

You have enough MPH to run in the 8.30 range, but with a non adder combo your 4.10 and 1.60 low gear is a 6.56 launch ratio.. The Drag radials are kind of throwing a monkey wrench into the mix for me, I dont have any good info for a NA with them, I would suggest trying a 1.80 low gear, I know that would be expensive to "try" but a simpler "try" would be to change the rear gear just to see if you could get the 60' down into the range it should be. A 4.56 rear gear would be about the same change as the 1.80 planetary. Borrow one from someone and give it a try
 

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The 60 foots are definitely soft for the ET. Taking the tire out of the equation, you need a numerically higher 1st gear and your converter is flashing at least 200RPM low.
 

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This interests me, as I have a "similar" combo, but 1.60 gear as mentioned above is way to soft.....just a guess, but a better trans ratio could net you at least a tenth in the 1/8th

60 fts could be in the low 1.2 range for your combo.....
 

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Discussion Starter #13
You may not have enough low gear to get the car moving quickly..

What is the RPM you are wanting the engine to run out the back?

You have enough MPH to run in the 8.30 range, but with a non adder combo your 4.10 and 1.60 low gear is a 6.56 launch ratio.. The Drag radials are kind of throwing a monkey wrench into the mix for me, I dont have any good info for a NA with them, I would suggest trying a 1.80 low gear, I know that would be expensive to "try" but a simpler "try" would be to change the rear gear just to see if you could get the 60' down into the range it should be. A 4.56 rear gear would be about the same change as the 1.80 planetary. Borrow one from someone and give it a try
We need to go through the traps at 7500, and thats where its at now. If we swap out gears or to a 1.80 itll be revving to high? Would it make sense to go to a 3.73 and a 1.80 or would they just wash them selves out and be where im at now?
The car works great now, would it make sense to try and make adjustments on the control arm to hit the tire harder?? I dead hooks now, just seems lazy
 

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Discussion Starter #14
This interests me, as I have a "similar" combo, but 1.60 gear as mentioned above is way to soft.....just a guess, but a better trans ratio could net you at least a tenth in the 1/8th

60 fts could be in the low 1.2 range for your combo.....
Thanks for the heads up, thats what were looking for is some compareson to other cars or what you guys think. ( though i dont want the car to do what the car in your avatar is doing, no big wheelies! lol )

We took this eng and trans combo outta a chevelle and put it in my chassis to see what it would do, and how well it works. it obviously picked up et, but the 60fts are the same as it was in the chevelle that weighed 140lbs more.
Thanks again guys
 

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We need to go through the traps at 7500, and thats where its at now. If we swap out gears or to a 1.80 itll be revving to high? Would it make sense to go to a 3.73 and a 1.80 or would they just wash them selves out and be where im at now?
The car works great now, would it make sense to try and make adjustments on the control arm to hit the tire harder?? I dead hooks now, just seems lazy
The starting line ratio, or first gear trans ratio has NOTHING to do with finish line ratio, as the finish line ratio is 1-1 trans......

The only difference in finish line rpm would be because the car is front halving quicker, and therefore trapping at a higher rpm, due to quicker et's and mph....
 

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The starting line ratio, or first gear trans ratio has NOTHING to do with finish line ratio, as the finish line ratio is 1-1 trans......

The only difference in finish line rpm would be because the car is front halving quicker, and therefore trapping at a higher rpm, due to quicker et's and mph....
This is correct.. Standard glide ratios are 1.76 and 1.82 from the factory.. in my old Bracket car that ran 8.80's I ran a 1.96 and a 4.88 gear.. 2550 lbs and big tires though.

You will really benefit from some more low gear in the trans. Your converter is working real well on the top end if you are crossing at just 7500.. converter slip is less than 6% with 96" of rollout in lights
 

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Discussion Starter #17
This interests me, as I have a "similar" combo, but 1.60 gear as mentioned above is way to soft.....just a guess, but a better trans ratio could net you at least a tenth in the 1/8th

60 fts could be in the low 1.2 range for your combo.....
What is your combo, specs on your set up if you dont mind me asking , or pm
 
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