My trip to the track...

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I finally made it back to the track last night to try out some of the suggestions. The only changes to the car was the resetting of the fuel bowl levels. I also got my adjustable strut rods installed and the front end was aligned for the first time using technology instead of my tape measure. The car rolls down the road even better.

The track was running an "Underground Arm Drop Drags" which meant the track wasn't prepped past the first 60ft. I don't think my car challenges the track much past the 60ft mark, so this could work. On my first pass hot off the street I got a little eager off the line which resulted in the following

60ft 2.036
330ft 5.636
660ft 8.674
MPH 80.70
1000 11.306
1/4 13.541
MPH 100.85

I let the car cool off for a few minutes before I went back up and staged the car as shallow as possible where you just lean on the converter a bit to wink on the bottom bulb. I managed to hit the right amount of throttle to keep the car hooked up resulting in the following pass.

60ft 1.894
330ft 5.452
660ft 8.469
MPH 80.95
1000 11.087
1/4 13.310
MPH 101.52

That set a new best for every stat. I have to admit I hung the shifts out to 6000 RPM, instead of the previous 5800 RPM.

You all suggested I explore more timing, so that was next on the agenda. Back in the pits I checked the initial timing and found it was set ay 16.5 degrees initial. I set the timing to 18 degrees and wondered if this would be too much timing. I headed back to the starting line and managed another masterful launch and got the following:


60ft 1.895
330ft 5.456
660ft 8.465
MPH 81.24
1000 11.075
1/4 13.289
MPH 101.86

This sort of shocked me as my old 340 hated a lot of timing, but this 360 is a different beast. If some is good then more must be better...right? Back in the pit I dialed in 20 degrees of timing and headed back to the starting line. The car was harder to get off the line hooked up resulting in the following:

60ft 1.922
330ft 5.457
660ft 8.444
MPH 82.07
1000 11.034
1/4 13.233
MPH 102.58

You can see the times fall off out the 330ft due to the spin off the line, but from there on out it just ran better and pulled harder. I needed to find out the limits of the timing, so back in the pit I dialed in 22 degrees initial. Back on the starting line the combination of the additional torque on tap and the starting line getting slicker resulted in the following:

60ft 1.981
330ft 5.532
660ft 8.524
MPH 82.06
1000 11.117
1/4 13.320
MPH 102.34

I attempted another pass trying to ease off the line and get the 60ft back to no avail as the tire spun off the line.

60ft 2.034
330ft 5.604
660ft 8.601
MPH 81.86
1000 11.199
1/4 13.407
MPH 102.05

Back in the pits I readjusted the timing to 20.5 degrees initial and made another pass which resulted in the following:

60ft 1.940
330ft 5.482
660ft 8.470
MPH 82.11
1000 11.061
1/4 13.263
MPH 102.26


I let the car cool off for 30 minutes and made one last pass for the night. The starting line was becoming very challenging resulting in the following:

60ft 2.040
330ft 5.582
660ft 8.561
MPH 82.34
1000 11.146
1/4 13.344
MPH 102.58

So what did I learn? The 360 likes timing to the tune of 20-22 degrees initial. The engine likes to be shifted around 6000 as opposed to 5800 RPM. As the tune gets sharper the traction is becoming an issue. I want to thank everyone for their suggestions. I am thinking I need to borrow a set of drag radials. What would you try next in the search for ET?
 
It seems to like the total number in the low 40's, not necessarily the initial number (harder to start).

Add some mechancial advance back into the distributor so you can keep the starter from straining and dial in the total timing it needs.

Have you jetted up at all?

What was the DA?

It's losing about 2-3 tenths in the first 330" which is probably the vac carb.

Nice work, it's coming around.
 
If your 750 vacuum secondary doesn't have the back metering body, I think there is still about 2 tenths going to a 750 double pumper. But at this point, probably only going to change the mph until the traction game is over. I would say a good set of drag radials are your next step in moving on.
 
I will have to check and see how much mechanical I can add back in. Since the starter is the small gear reduction unit, it doesn't seem to strain too much at 20 degrees initial timing.

I have not changed the jetting.

I have my weather meter in my helmet bag and forgot to pull it out and take readings. It was mid 70s and not too humid. Makes for a nice evening at the track.

I think I am losing 2-3 tenths because the car is traction limited. I have to ease into the gas coming off the starting line and I was still getting into mild wheel hop 20-30 feet out.

I think I need to look at quickening the advance curve and finding more traction.

It seems to like the total number in the low 40's, not necessarily the initial number (harder to start).

Add some mechancial advance back into the distributor so you can keep the starter from straining and dial in the total timing it needs.

Have you jetted up at all?

What was the DA?

It's losing about 2-3 tenths in the first 330" which is probably the vac carb.

Nice work, it's coming around.
 
You are a high 12 second car. Your 60ft is not good at all. Your carb is not letting the engine get what it needs. 3/8 fuel line would help too from new sender to pump. A carter super strip with regulator would be nice upgrade. We know money might be an issue but 750 DP would bring her to life. But this is why this is fun because you know that it can do better, it's the satisfaction of trying to figure out what to do to get to that number and then crushing it. But, if you end up wanting to buy a 750 dp, let me know I am thinking of selling mine, it's three years old.
 
Right off the bat, I have to say..I am having fun! Last time at the track we played with the timing and managed to whittle a 13.50 down to a 13.23 @ 102.58. Over the last few weeks I have made some changes to the car. The first change was to the lightest secondary spring Holley makes which is the white spring. I though it might cause a bog, but with the 3200 stall converter and 3.91 gears it was not a problem.

The second change I made was to the pinion angle. Seems I swapped in the 8 3/4 without a single pinion angle wedge in between the perch and the spring. When I checked the pinion angle I found it was pointing up 1 degree. I swapped in 4 degree wedges and now the pinion is pointing down 3 degrees. I think it needs more downward angle and I have 6 degree wedges waiting in the wings for another day.

The third change is one that is not highly regarded on this board and I have to admit my first attempt at it last year was a dismal failure. This time around I went with the "Taurus" fan to replace my 7 paddle fixed fan. I want to say that this mod was not trivial by any means. In order to fit the fan I had to trim the shroud to make it thinner. I also had to recess the radiator into the radiator support and shift it to the driver's side and inch to get the fan motor to clear the water pump pulley. I wired the fan to a soft start controller the starts the fan at 60% speed at your set temperature and ramps the fan speed up to 100% when the engine reaches 10 degrees over the set temperature. The controller also has a manual over-ride to shut down the fans with a switch. I bought a throttle switch and planned to have the throttle switch shut off the fans at WOT. As it turns out I never got around to wiring up this switch. The controller also runs the fans for an additional 30 seconds after you turn off the car. This turned out to be very handy in the staging lanes to cool off the engine.

Now to the good stuff>>>

My first pass resulted in the following:


I hung the shifts out a little further then intended as I saw the tach hit 6300 rpm. I think the pinion angle change helped out the 60 foot times as the 1.86 beats my old record of 1.89.

The next pass I got the shifts in at 6000 RPM which resulted in:
https://lh3.googleusercontent.com/-...AAAAAAD8/dtb8grz8d6s/s640/Dart090314_1302.jpg
Dart090314_1302.jpg



The follow up pass resulted in....


I am so close at this point.... I decided to pull the spare tire and jack out of the trunk and remove my tool bag to reduce weight. The problem is I was pulling weight over the back wheels. Back at the starting line for what was likely my last pass of the night, I got a little eager off the starting line and blew the tires away resulting in a 13.22 @ 105 MPH.

Based off the MPH, I had more then enough power to run as 12.99x if only I could hook it up. I slipped into the back of the staging lanes for one more pass. I really took my time staging and EASED into the throttle leaving the starting line resulting in...


And just like that....another milestone!
 
You need to improve your 60ft and you will see the biggest improvement. What tires and suspension setup are you running? How much travel do you have in the front before the tires come off the car when jacking it up?
 
The 8 3/4 is supported by MP 002/003 springs in the stock locations. The front has /6 torsion bars with worn out stock shocks and after market (adjustable) strut rods. Front tires are a 195R-15 on a 7" rim and the rear is a 255R-17 Riken Raptors on an 8" rim.


Because I run low hanging headers the front end is cranked up quite a bit, but there is probably 4-5" before it tops out. I never really checked, so this is just a guess.


With a set of drag radials I could really lean on the converter and get the 60 foot times down.
 
Ya, I would look at even the Nitto Radials if money is tight or if not too tight, look at the M/T which are the best radials. That will help a lot. What shocks are in the rear? Snubber?
 
Well done a very enjoyable read and i'm assuming, your first foray into the 12's.
A cheap upgrade i did on my Dart was the 2" supersucker spacer, that netted me .15 and 1.5 mph and only cost me 60 dollars from Terry Walters performance but results can vary dependent on your combo.
Mick
 
Well done a very enjoyable read and i'm assuming, your first foray into the 12's.
A cheap upgrade i did on my Dart was the 2" supersucker spacer, that netted me .15 and 1.5 mph and only cost me 60 dollars from Terry Walters performance but results can vary dependent on your combo.
Mick

Not my first foray into the 12s, just my first with a MOPAR. It is sad to think my '73 340 'Cuda and my 70 Challenger RT 383 never made it this far. They always got sold to support some family milestone before they reached this level. The last MOPAR I had was a 76 Aspen RT with a 360. That was another fun car to take to test and tune.

I am not sure I can fit a 2" spacer under my hood even with my drop base air cleaner, I will check it out though.
 
Craigslist traction! start searching

I just have to look on the far side of my garage to find a pair of MT ET Drag Radials 255R-15. They just happen to be on a set of wheels that won't fit on the Dart and they are currently keeping this "other" car a roller. Even still I have been scoping Craigslist to see if someone was dumping some decent tires at the end of the season.

Quick check found out there are no "cheap" 15x8 rims with 5.25" offset I need to fit the back of my car...grrrr.
 
I just have to look on the far side of my garage to find a pair of MT ET Drag Radials 255R-15. They just happen to be on a set of wheels that won't fit on the Dart and they are currently keeping this "other" car a roller. Even still I have been scoping Craigslist to see if someone was dumping some decent tires at the end of the season.

Quick check found out there are no "cheap" 15x8 rims with 5.25" offset I need to fit the back of my car...grrrr.

Congrats! Keep looking for rims,use the tires. That thread on the longer shocks with S/S springs, is good info.(Use a basic 18-22 dollar O Reilly's/Auto zone rear gas shock. Order for a 70-71 Chrysler Imperial)
 
Congrats! Keep looking for rims,use the tires. That thread on the longer shocks with S/S springs, is good info.(Use a basic 18-22 dollar O Reilly's/Auto zone rear gas shock. Order for a 70-71 Chrysler Imperial)

In the link on SS springs they mention using a 68 Imperial shock on the back. Do you think there is any difference between the 68 and the 70-71 shocks? I am having better luck finding wheels with either 5.125" backspace or 5.50" backspace. The 5.50" backspace wheel would require a .250" thick spacer. The 5.125" wheel will have the tire sidewall close to the fender lip, but some careful trimming could provide the needed space. It is just hard to spend $109 for a steel rim.
 
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