I went to Orlando last night for Test and Tune. Sea level, 65F
Car is just a cruiser, was hoping to get in the 12’s, but that didn’t happen.
For reference my 06 Mustang with a tune went 13.7 (2nd slip). That car is only 300hp and has to weigh the same as the Challenger.
The 5.7 is supposed to be 385hp, I was hoping to be 400hp with the headers and CAI.

Would appreciate opinions on whether there’s 0.4 to be had.
70 Challenger, 5.7 crate motor (TTI shorty headers), 518, 3.73 Dana, 275/40/18 rear tire, lowered to 25PSI
I was hoping to get the weight, but they didn’t have the scale open.

1st run: Didn’t really get on it, and shifted too low, maybe 4500
2nd run: Better, shifted at 6k, it actually felt like it broke up a little in 2nd right before the shift to 3rd. Nothing major, didn’t cause the 0.4 I’m looking for.
3rd run: Getting late, there were several shutdowns for cleanup, seems like all the imports had issues. So I decided to get on it a little harder off the line, spun, and it spun in 2nd and got squirrely, I let off and ended the night.

I was lucky to get the 3rd pass in, 2 cars later a TrackHawk got loose and hit the opposite wall about 200’ out, ended up facing the tree and all the airbags went off.

Your 60' times are, as it was explained to me before (per my very own results - see attachment, I'm the 13.13 lane): TERRIBLE!

So this could be weight transfer, or lack there of, or even the tires spinning w/o you realizing it. Seems like running at 25 psi may be contributing to it...could you go lower to hook 'em better? (not sure what tire you are running)

Anyways, in that timeslip of mine: I'm aiming to replicate what the other lane posted, which again, the launch and the first 60' have a significant contribution to.

You're losing a lot in the 60. Until you get it to hook you're wasting your time.

101-103 mph show you have the steam to get in the 12's.

Unfortunately 103mph really isn't enough to get into the 12s.

MAYBE if you can get the car moving in the first half of the track it'll pick up a bit... But it's really just not showing it's got the power to weight ratio to make to 12.99.

For sure it either needs more traction, more gear, and or more converter to help you get there.

Appreciate the inputs, so I plugged some numbers in the Wallace calculator and something isn't adding up.
Either the car weighs way more than I'm guessing, or the power is down.
Maybe a combination of both, and tire spin / crappy driver?
I know the 60 sucks, but even if 1.8 is possible, does that pick up 0.5 sec?

From calculators, 1st 2 columns are inputs, 3rd column is prediction.

MPH Weight HP
103 3800 325 hard to believe the MP crate is this low
103 4400 375 seems heavy, I weigh 185

Weight HP ET / MPH
3800 375 12.60 / 107
4400 375 13.20 / 102

Wallace 1/4 calculators should be thought of as a ballpark figure.

My car weighs 5100 lbs at the track. It has an advertised 621 hp. It ran 11.82 @ 120.

According to Wallace it either has 679 hp or 610 hp. It depends on which calculator you use.

There are simply too many variables for it to be precise.

typically on cars like yours, picking up .2 in 60' will garner 2X that gain at the other end. .4 wouldn't be out of range.

Maybe.

Let me give you my recent experience. 4000+ lbs 67 coronet. Stockish 383. Only mods is Holley 750 CFM carb, RPM intake and small cam. 3.55 gears short street tires. 11" converter. Ran best of 14.82 with a 2.2 60 foot. Uncontrolled spin off the line.

Similar weather but put the very old baldish street radials (they were destined for the garbage) on it and a pinion snubber (I think this made a huge difference). 1.998 60 foot and ran 14.37. With a little more work the 60 foot will get even better.

Moral of the story is there are some easy things that can be done to improve 60 foot. Send lesson is you gotta improve your 60 foot. Once 60 foot are better worry about et.

A few things:
1) For the calculation there are two things you need to do. Correct to std conditions, and adjust for net hp verses gross hp. Sounds like you actually ran close to std conditions. 30 to 40 hp is not an unrealistic difference between net and gross hp.

2) Your 3 runs are all over the map. I would not change anything and simply get more track time at least until you get consistent mph and some no-tire spin runs under your belt. This will make the next best steps more clear.

3) What are you willing to change to get to 12.99? If you have tire spin, simply put a better tire on it like a MT ET Street radial. If you are using a typical street tire with a 300 - 400 traction rating (e.g. BFG), you’ll be hard pressed to get better than a 1.95 - 60’ time. That won’t get you to the 12s.

4) If that doesn’t get you there, then you are probably looking at a converter. And, based on your hp/mph, the converter you might need you might not like how it drives on the street.

If you don’t want to change tires and converter on your street car (which I can understand), you’ll need to open the hood to find more horse power.

Years ago, I did not want to change my converter or my BFG tires and was stuck in the 2.0 - 60 ft realm for a long time. Kept working on more hp. When I finally got to 12.8 -12.9s, I was trapping 107 - 109.

Said differently, you’ll need a much better 60 ft, or you need another 50 hp, based on your one time slip.

More great input, much appreciated.
A little more background:
Rear tires are 18" Sumitomo 320 rating (need replacing)
Convertor stalls around 2800
I pulled through the water and just did a rolling burnout until it started to push the rear end out (maybe 3-4sec), didn't power brake it and do a long burnout.
I probably only left the line at 2k max on the best pass.
Car definitely spun the tires on 3rd pass, even into 2nd, actually spooked me.
You can see on the video it get loose 150' out.
Was disappointed only getting 3 passes while being there 4hrs.
Hoping to get it weighed next time.
Not looking to change converter.
Any suggestions for next set of tires and pre-stage method to warm tires?

For what it's wort I have a 73 Challanger with a hopped up 360 4 speedm 3.55 gear. I wiegh about the same as you. it weighed 3775 with me. It has headers with full TI 2 1/2 exhaust, aluminum intake, power steering and aluminum wheels. with street BFG T/A's one time it went 13.25@105. Very touchy on the leave to hood. With drag radials it went 12.75@107. With a 4.30 gear and slicks it went 12.50@110. All runs with exhaust and air filter in place. You can see what different results can happen. Even more drastic. My Volare street car. With radial T/A's 3.91 gear ,13.60's@107. No changes but slicks and open exhaust 11.90@111. Bigger cam, looser converter, 4.30 gear 11.0@122 no other changes. Start with some MT drag radials.
Doug

Like Doug said, start with tires, you said you rolled thru the water you might have turned the tires in the water and carried some up in the wheel well and it dropped down on the tire down track as why you spun down track. One thing at a time and you will see what improvements you are making, with setup (minus tires) that should hit the 12’s.

If I was you I would buy a set of 15 inch wheels 8 to 10 inches wide and mount a set of M/T 28 inch x10.0 or maybe 10.5 wide bias ply slicks and use them only at the track and save your street tires for the street
You're probably looking at .25 or quicker ET improvement with those changes only and 5 or more MPH increase
I had an old time Mopar full sponsored SS racer drag racer tell me years ago (mid 1980s or sooner) to focus on the first 100 Ft. on the track and the rest of the race would take care of itself, This was before 60 ft.clocks, timers, were in use. He was correct:
R.I.P Joe Allread

I agree. Here's my example 87 Monte Carlo SS, NA pump gas [93] sbc stroker, HR, 950/4150, TH 400, 12in 2500 convertor, 342 gears, 3580 w/driver 10.86 @125.6. 1.61 60ft. Hoosier QTP's 27.5 x10.

Invest in good tires. They won't say Sumitomo on the side.

It can be tricky to get low profile tires to hook.

More stats on my car: 5100 lbs, dynoed at 756 lb/ft @ 2800 and 548 hp @ 5000. 2.54 open diff, traction control, and 275/35-20 Michelin Pilot Sport 4S.

Dropping the air pressure to 28 psi helped the launch. You can't go much lower on this type of tire because it will lift the center of the tread.

I barely load the converter. Staging at 1400 and driving it out of the hole gets me 1.88 short times. With this much torque if the tires spin you're done. It won't hook up again until you're completely out of it. However, if I do my part it runs consistent 11.80s at 119-120 mph.

I haven't been to the track with the new limited slip but I doubt it would make much difference. The car either hooks or spins till you lift.

Tires will make a big difference. With the Pilot Sport 4S it usually hooks up on the street at 45-50 mph. With Pilot Sport AS4 all season tires it spins above 60 mph, depending on the surface.


A good tire will feel different in regular driving, too.

You've got a lot of time and money in that car. Don't cheap out now. Give it the good stuff. You're looking at a big performance improvement for that extra $100-$150 per pair of tires.

I can't justify buying dedicated 15" rims and tires, that would only be used a few times.
Looking at Nittos or MTs in the 275/18 sizes, rims are 9".

Any opinions on what would work and still able to drive on the street the other 95% of the time?

MT et street r's are great, I now have M&H drag radials on my 68 Charger & my 2020 T/A 392 Challenger, they work GREAT for street or strip. they drive almost as good as a regular street tire.

You need sticky tires in a bad way. M/T ET Streets are what I'd be looking at.
All the power in the world is going nowhere on the tires you have.

Video shows the car really spinning the tires - I'm with everyone here on getting sticky ones.
Taking unnecessary weight out is essentially free power.
If the car's yawing in the water, just turn into it as you would a skid (shouldn't take much), and then drive out.
Seat time is a big part of any kind of motorsport.

Lot's of options, if it never rained.