Opinion from some of you long time Mopar racers

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Especially if you are footbraking, see if you can borrow a proven 750 some time when planning a test & tune. Maybe a 2" 4-hole spacer too. If the set-up (jets/squirters/pump cams) is off, it can affect how the converter flashes as well. Check for proper closed & open valve spring pressures.

I had a very similar combo in a home built (bought from a friend) 2x3 frame 2800-2850 lb Challenger in the '80's & 90's. All time bests were 10.22 @ 130-131 and 1.37 60'. But it was a std. stroke 360+.040(?) (cut down DC 355 pistons) with 750 DP, .585" flat tappet cam, Harland Sharp 1.5 rockers & a little less compression. Heads were ported with the Direct Connection porting templates, same tire, gear, trans & converter. Converter was a Turbo Action 4200 and had JW simply freshen it over the years. I don't recall the actual flash. I tried shifting at 7100, but found it ran the same @ 6800! Suspension was ladder bar/coil overs all around, but nothing fancy. Geometry never seemed right, but it ran faster the lower I made the car and more consistent when I added 50-70 lbs to it later in its life.

I always tried to stay conservative. I guess I had the combo figured out, but its long gone. Hope all the suggestion help you with yours.
Thank you for the info and suggestions! I am foot braking. I've never believed in delay boxes or any of that stuff. That's not drag racing IMO.
I'm going to New England Dragway this Saturday to make some final test runs for the season. I don't think I have time to locate and borrow a smaller carb before then. I'll probably pick one up over the winter and test it next spring.
 
Thank you for the info and suggestions! I am foot braking. I've never believed in delay boxes or any of that stuff. That's not drag racing IMO.
I'm going to New England Dragway this Saturday to make some final test runs for the season. I don't think I have time to locate and borrow a smaller carb before then. I'll probably pick one up over the winter and test it next spring.


You don't have or want to use a transbrake? If the car has it and you aren't using it, that may become of the issue.
 
You don't have or want to use a transbrake? If the car has it and you aren't using it, that may become of the issue.
Current 727 doesn't have a trans brake. I'm not opposed to having one. Not sure how they are used/how they work as I have no experience with them. I may look into that over the winter as I have to pull the trans and converter to have the converter reworked. I'll contact the guy who built my 727 about this upgrade.
 
FWIW, it's my understanding that a trans brake equipped transmission requires more line pressure. So even if you don't use it, it will be bit slower. Not by much, but possibly worth considering before spending more money while trying to go faster.
 
After making some jet and valve lash changes ran a best of 10.49 @ 122 this past Saturday at New England Dragway. Finally seeing what the car is capable of!
 
Also, was able to weigh the car at NED. Weighs 2680 without me in it. 2890 with me in it.
 
After making some jet and valve lash changes ran a best of 10.49 @ 122 this past Saturday at New England Dragway. Finally seeing what the car is capable of!


Is that MPH correct? If so, that's barely over 400 HP.

If we use your ET (which I never do) that puts you at a paultry 450 HP.

Something isn't right. Your MPH is down for your ET and that tells me it's down on power.
 
Looking at the op original he lost 2 mph on the big end so thats going the wrong way.

Personally I would never run 1050 on a small motor. I think thats way to much. IMHO
 
Looking at the op original he lost 2 mph on the big end so thats going the wrong way.

Personally I would never run 1050 on a small motor. I think thats way to much. IMHO


That engine will take two 1050's with no problem.

He's 200 HP off somewhere. There isn't a carb on the planet that will kill 200 HP.
 
After making some jet and valve lash changes ran a best of 10.49 @ 122 this past Saturday at New England Dragway. Finally seeing what the car is capable of!

I think something is not right. I would check cam setting.
Car should be faster and quicker I think.
 
I appreciate everyone's input. However keep in mind, as I have said it other posts, the torque converter currently in the car is WAY too tight and is killing me on launch. That is going to be remedied soon.
Also, I've made no changes to the ladder bars or rear shocks as they were set when I bought the car.
The HP figure I mentioned originally isn't my number, it's what I was told the engine would put out by the person i bought 5he car from. At this point i have no idea what the actual HP is.
And finally I've made no changes to ignition timing. It's set at 34 BTDC, which is where it was set when I bought the car.
Overall I'm extremely happy with last Saturday's results. Is there more left in the car? Absolutely, and I'll get it wrung out in due time.
 
good morning all.

Seeking opinions from some of you heavy hitters out there who have been racing mopars for a while.

After being out of drag racing for 24 years I decided to dive back in late this summer. After a little bit of searching, I decided on a 72 Dodge Dart that was already built and turn key.

Specs on the car (as supplied by the previous owner):

360 block bored .070 over
custom 3.685 offset ground crank, internally balanced with 6" SBC small journal rods
Ross custom pistons with 13.8 compression
W2 race ported heads with 2.08 intake and 1.65 exh Manley valves. Norris stainless steel 1.6 ratio roller rockers.
Competition Cams full roller cam .646 lift @ 105, 106 centerline.
Victor intake with Holley 1050 Dominator.
MSD 7AL with crank trigger.
Hedman Husler 1 7/8 race headers
LT 727 TF with Cheetah manual reverse pattern valve body.
Turbo Action 4400 converter (allegedly, not flashing at that RPM)
Dana 60 with 5.13 gear
ladder bar rear with older Comp Engineering single adjustable coil overs ( which I have no idea how to adjust and can find no info on Comp Engineering website). Ladder bars are set on the top hole in the front brackets, which sets bottom bar of ladder bars parallel to the ground.
stock front suspension. Neither of us have any idea what shocks are on the front as there are no markings of any kind on them.
He told me engine should be producing around 600hp. He said to shift at 6800 rpm, but I'm shifting at 6500, with 7000 going through the traps on the 1/4 mile.
no idea what the car weighs, has fiberglass front fenders, hood, doors and trunk lid, all windows are lexan. I'm guessing maybe around 2200-2500.
running 32X14X15 rear slicks.
60 foot times average between 1.52 to 1.55
best 1/4 ET has been 10.62 at 124 and change.

I feel there is a lot more in this combo, he says it should be running in the 10.20s with 60 foot times in the 1.30s. We both seem to agree that the torque converter is the bad actor and it's too tight.

My question to you is do you think the converter is the issue here or perhaps something else? I haven't made any adjustments to the ladder bars or coil overs cause, frankly, I don't know where to begin with those, as I have never run that type suspension before.

Any constructive suggestions will be greatly appreciated. Planning on doing some test/tune runs next weekend before the tracks close for the season.
I think your car has more in it. Something is not right or ideal.
Seems to me your car is not right off the line and not right on the top end either. Should have more mph.
My dart with a 344 cubic inch motor used to run 11:20 at 118
With a 1.52 60 ft.
If that 4400 converter is the off the shelf Mopar performance converter, that is part of the problem with those w2 heads.
A quick look on the Turbo Action website at the pro series converters
Paul has a note there pertaining to w2 heads. They need loose converter. I used to have that 4400 converter. Car was lazy off the line. I called Paul, gave him full specs of the car. He rebuilt my 727
Into a 4600 904 converter specifically for w2 heads.
I put in an aluminum 904 drum as well and a little more cam
With 2:74 low first gear. My car picked up 1/2 second and consistent 11.20,s. You have a lot of tire on there too which needs some converter to get moving.imho. Also I have always found best timing for w2 heard is 35 degrees. I have seen some motors drop 50 horse from 2 degrees timing. I also agree that 2 big of a carb
Will affect stall speed. See if you can borrow a well tuned 950 hp.
Your car is not far off. I figure you should be 9:80 to 10:1 et.
Just my two cents.
 
Valve Springs. Since you don't know the history of the car in regards to number of passes and how long it sat from time to time and have the Cam info this is an easy thing to check. That may be in left field but it's something worthy of removing from the equation.....

JW
 
122mph is only good for a 10.82, so it’s def not pulling the back half for ****.

Don’t take this the wrong way...... the speed is so low I have to wonder if you’re letting off before the full 1/4 mile?

10.49 “should be” be closer to 126.5mph.

If the motor pulled the full 1/4 like it should, it would probably run better than 10.49...... and better than 126.5.
 
122mph is only good for a 10.82, so it’s def not pulling the back half for ****.

Don’t take this the wrong way...... the speed is so low I have to wonder if you’re letting off before the full 1/4 mile?

10.49 “should be” be closer to 126.5mph.
I appreciate your input. But having almost 23 years of drag racing experience I'm definitely not getting out of it before the finish line.

If the motor pulled the full 1/4 like it should, it would probably run better than 10.49...... and better than 126.5.
 
Here are the cam specs:
Competition Came full roller
Grind number 4311B/4268B R 106.0 + .0
Gross valve lift intake .654, exhaust .655
Duration @ .020 tappet lift 302 intake, 309 exhaust
Valve timing @ .050 intake open 29 BTDC, exhaust 64 BBDC, close intake 61 ABDC, exhaust close 32 ATDC.
Installed at 106.0 intake center line
Duration @ .050 :. Intake 269, Exhaust 276
Lobe lift: intake .4360, exhaust .4370
Lobe separation 106.0
Valve adjustment: intake .020, exhaust .022.. however right now they are both set at.022. Before this past Saturday they were both set at .024 by the previous owner.

On the cam card there are hand written notes ... ' in at 102' and another handwritten note 'intake clearance .140, exhaust clearance .280'

Hopefully this info will help with suggestions.

Info on the torque converter currently in the car. Its out of Frank Lupo's Converter Dynamics shop. It's supposed to be a 4400 unit. The previous car owner said he bought it new from them but that it set, in the box, on a shelf in his garage for 14 years. I don't know enough about torque converters to know if sitting in a box for that length of time can degrade them.

The 727 Torqueflite was built brand new by LT Transmissions in Colebrook, NH this past April.

The engine was freshened this past April with a cylinder home, new rings and bearings. The W2 heads have K-Motion springs which the previous owner said were installed new out of the box when the engine was assembled. Allegedly this engine only had one break-in pass on it before I bought the car in July. So everything appears to be new or recent in the power train.
 
In a nutshell...... it’s missing a fair amount of speed.

NED is almost always quicker/faster than LVD.

You went 124 at LVD, 122 at NED.
It’s going the wrong way.

Something appears to not be happy.

Have you done, and do you know how to do a flash stall test?
What the converters stall speed is “rated” at means nothing.
What matters is what it stalls behind your motor.

That cam, race car, w2’s....... you’ll be wanting at least 52-5500 flash stall.

Anyone get any video of the car?

I’d also suggest warming the motor up and doing a compression test.

Here’s the way I see it...... you’ll have all winter now......
Pull the motor, put it on an engine dyno...... see where it’s at.
Then you’ll know how fast your car “should” be, and have better data to give to a converter shop.
 
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Looking at the moroso P/S calculator...... even if the motor made a pretty conservative power number(for that combo......550hp), and it was a typical 90% car....... it should still be going right about 130mph at NED in fall air.

Even 500hp and a 90% car shows close to 127mph.

Either the motor is way off the mark, or there are some problems with the car.
 
Here are the cam specs:
Competition Came full roller
Grind number 4311B/4268B R 106.0 + .0
Gross valve lift intake .654, exhaust .655
Duration @ .020 tappet lift 302 intake, 309 exhaust
Valve timing @ .050 intake open 29 BTDC, exhaust 64 BBDC, close intake 61 ABDC, exhaust close 32 ATDC.
Installed at 106.0 intake center line
Duration @ .050 :. Intake 269, Exhaust 276
Lobe lift: intake .4360, exhaust .4370
Lobe separation 106.0
Valve adjustment: intake .020, exhaust .022.. however right now they are both set at.022. Before this past Saturday they were both set at .024 by the previous owner.

On the cam card there are hand written notes ... ' in at 102' and another handwritten note 'intake clearance .140, exhaust clearance .280'

Hopefully this info will help with suggestions.

Info on the torque converter currently in the car. Its out of Frank Lupo's Converter Dynamics shop. It's supposed to be a 4400 unit. The previous car owner said he bought it new from them but that it set, in the box, on a shelf in his garage for 14 years. I don't know enough about torque converters to know if sitting in a box for that length of time can degrade them.

The 727 Torqueflite was built brand new by LT Transmissions in Colebrook, NH this past April.

The engine was freshened this past April with a cylinder home, new rings and bearings. The W2 heads have K-Motion springs which the previous owner said were installed new out of the box when the engine was assembled. Allegedly this engine only had one break-in pass on it before I bought the car in July. So everything appears to be new or recent in the power train.

I would check the 102 to be sure they did not go the other way. jmho which I highly value.
 
In a nutshell...... it’s missing a fair amount of speed.

NED is almost always quicker/faster than LVD.

You went 124 at LVD, 122 at NED.
It’s going the wrong way.

Something appears to not be happy.

Have you done, and do you know how to do a flash stall test?
What the converters stall speed is “rated” at means nothing.
What matters is what it stalls behind your motor.

That cam, race car, w2’s....... you’ll be wanting at least 52-5500 flash stall.

Anyone get any video of the car?

I’d also suggest warming the motor up and doing a compression test.

Here’s the way I see it...... you’ll have all winter now......
Pull the motor, put it on an engine dyno...... see where it’s at.
Then you’ll know how fast your car “should” be, and have better data to give to a converter shop.
i do have some videos that my wife made of different runs at both 1/4 and 1/8th mile tracks, but i'm having problems getting them to upload here.
 
i do have some videos that my wife made of different runs at both 1/4 and 1/8th mile tracks, but i'm having problems getting them to upload here.
I generally load stuff to YouTube then I can copy and paste it here for videos...
 
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