Whats the best time for a factory stock duster 1/4 miles ??

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That's why we love A-bodies! No power steering, no a/c =super light weight. 3.91's from the factory with a under rated (power) 340 or 360. That equals high 13's. Fast enough to beat most big blocks! That's the A-body secret. You just got beat by a Duster! Yea you did!
 

Well, after a few pages of smoke looks like the 340 turns out to be the lil firecracker everybody thought they were....I didn't see much bragging on a magnum...340 will spin up super fast and keep pulling till valves float...the magnum is one for big build (easily replaced)
 
The shorter stroke has the ability to spin up the rpm band quicker. If you take both engines and built them as close as possible the same way, the 340 will always spin up quicker. Installed in a car, with the same transmission, gear ratio and tire size, the 340 will spin up quicker. You’ll need to change the gear ratio in the 360 in order for it to complete.

This is where the 340 wins.

Getting the 360 to compete is only a gear change away. It’s needed due to the longer stroke taking more time to complete its travels. The 20 extra cubes should still produce more torque and do a longer time doing so. If you gear the car to allow the 360 the ability to rev up as quick as the 340, the 360 will win.

The 340 is a lil’firecracker.
 
Back in the day when I was driving my 69 Coronet R/T I had a buddy buy a new 340 Duster, 3:23 sure grip, 3 speed manual. It would run high 13's to 14 flat in street trim.

Have any of you guys heard of the F.A.S.T. series that runs in the NE?
Some of these cars are amazing...ck it out, 71 Duster 340 11.27 @ 120 MPH
Fast Races

Those cars are farrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrr from stock!!
 
I got my '68 FB FS 340 in June 1969 from the original owner. It had 17,000 miles on it and cost me $1700, plus $100 for the Cragar's on it. Never saw the original wheels and tires, so he must have left them with the shop that put on the Cragar's. I took the 'Cuda to all the drag strips in SoCal and had 350 timing slips before I had 60,000 miles on the car. Best time was 13.48 @ 105.38. The only things not original were H70x14 retread tires with sticky compound and at the strip I droppsed the exhaust at cutouts that the original owner had installed. Not open headers, but at least not through the mufflers either.
At OCIR, the car weighed 3050. Not bad for a FB 'Cuda.
I suspect, but never could verify, that this very early build 340, built in Sept 1967, had the 4bbl cam as it was at least 0.3 seconds faster than any other 340 I ran across at the strips. OCIR was my favorite as in the fall the fog would come in and the car ran its best at 50°F.
I still have it after 53 years. It is getting new paint now after AMD did the rear quarter panels and valance. Otherwise, it was solid. Black on Black, and that is the way it is going back together.
 
hi guys ! i wanted to know what is the best time ever recorded for a 340 duster or demon .. bone stock ... i know that they used to do the quarter mile in 14 sec but a lot of people said to me that a lot of was capable to enter the 13 sec range ???

thx
I know of two cases where stock meant stock. A lady I knew bought a '72 Demon, 340 auto with 3.91's. Nothing touched but bolted on slicks so traction was not a factor and it went 14.2's. Another is a guy that bought a '70 340 Duster 4 speed brand new. He tried to get into the 13's stock with slicks and never made it. Very very low 14's but never hit his 13.
 
Altitude also makes a major difference. My Cuda is nowhere near as quick at Bandimere (5800') than it was in SoCal at 100'!
 
This post is exactly right ....see post #50 Hersbird for a good summary....

Ronnie Sox in a factory equipped totally stock 1970 Duster 340 with a factory 4 speed and equipped with a 3.91 Sure Grip did a best of 13.98 ET at around 100 MPH in a Rapid Transit System test that was reported back in that timeframe.
Sox was one of the very best drag strip legends and he could shift a four speed like no one else.

These cars improved and responded well to basic bolt-on mods - cam, headers, intake, carb, ignition upgrade, torque converter upgrade with higher stall and maybe a valve body update....and a pinion snubber with larger good sticky rear tires.

But these mods were NOT part of a factory equipped car or factory option package.

One of the draws to buying the original 1970 Duster 340 was the low MSRP of $2,547 - well equipped. Also, Chrysler Plymouth provided a 5 year - 50,000 mile factory warranty on the drive train - the best in the auto industry at that time.
The Duster 340 was less expensive than the 1970 Dodge Dart Swinger 340 and it was marginally faster due to shorter wheelbase, and slightly lower weight.
Car Craft Magazine in May 1970 tested the 4 budget muscle cars - the Duster 340, the Dodge Dart Swinger 340, the Chevy Nova SS 350, and the Ford Mustang Mach 1 351 Cleveland - the Duster 340 won the 1/4 mile drag test and was the least expensive car in that group.
 
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I know this isn't the answer to your question, but I ran a best of 14.28 at 98+mph in my '69 340 Swinger back in early 1970. This was bone stock with a 727, non-Sure Grip 3.23, and stock exhaust
I ran a similar numbers with my 1970 Swinger340/4speed/3.55s . At a tic over 11,000 on the Odo, completely stock, on those pos E70-14 polyglass tires; she went 14.4@98 and change, roasting them thru two gears, and trapping in the bottom of 4th gear.. Race weight was 3330, with me in it.
Not long after that, I got me some custom-built slapper bars. But they couldn't do much on the street with those tires.
IIRC, the early Duster was a lil lighter, but not by much.
 
I ran a similar numbers with my 1970 Swinger340/4speed/3.55s . At a tic over 11,000 on the Odo, completely stock, on those pos E70-14 polyglass tires; she went 14.4@98 and change, roasting them thru two gears, and trapping in the bottom of 4th gear.. Race weight was 3330, with me in it.
Not long after that, I got me some custom-built slapper bars. But they couldn't do much on the street with those tires.
IIRC, the early Duster was a lil lighter, but not by much.
Not to mention that dusters and demons have better aerodynamics. Kim
 
yep-16+ seconds for a 4-speed 340 'cuda with a 3.55 SG?
Never drove one, but I'm pretty sure you'd have to work at going that slow :dontknow:
The Barracuda is IMO the pig of the A-bodies, being maybe close to 150 pounds heavier, option for option, than a Duster or early Dart. Thankfully the extra weight seems to be over the rear tires. If I take the power-steering off mine, I can get real close to 50/50....... with the battery in the trunk, and alloy heads.
Speaking of 16 second quarters;
In about 1978, I inherited a 71 Demon 318/904/3.23s. It had been my brother-in-laws car. He related to me what it it had done in the quarter, when it was nearly new (he was first owner.) IIRC, he said 15.7something @ 79something . This car had P/S and PDB, with a 7.25, and nothing else.
So 16+ for a 340/4-gear/3.55s, is almost two seconds off the mark.
 
I know of two cases where stock meant stock. A lady I knew bought a '72 Demon, 340 auto with 3.91's. Nothing touched but bolted on slicks so traction was not a factor and it went 14.2's. Another is a guy that bought a '70 340 Duster 4 speed brand new. He tried to get into the 13's stock with slicks and never made it. Very very low 14's but never hit his 13.

I think the difference maybe lies in the Thermoquad...
 
I can offer a "sideways" comparison. Many of you know, during the "gas crunch of the 70's" that I swapped a stock 71 high compression 340 into my 70 RR 440-6 V code car. So this was a 4 speed, Dana, 3.54 gear, with aftermarket "knee knocker" A/C, and after a brief period to recover financially after the swap (couple of months) I put Hedman headers on the car. (It had had 318 manifolds and Y pipe initially)

That thing, even with my lead foot driving, would better 17 1/2 MPG, and would STAY WITH OR PULL a bone stock 383 RR. So "right there" we can "refactor" the 340 to 335 HP if that is an accurate figure for the 383 cars LOL
 
Please don't believe the 1972 hype that they got any slower. They had to lie about a lot back then. My farther bought a 71 340 4 speed with 3:55s He did have A/C, power steering/ brakes. Follow year I purchased a 72 340 3 speed standard with 3:91s
I ordered it without any options other than shark grill and stripe pkg.Power nothing. We street raced at least a dozen times and my 72 beat his 71 every time but once. We switched cars and same results other than once I beat him in his car and I still think he peddled it We never ran his at the track but I made a few passes with nothing but slicks and best was 13:71 @ 106mph.
 
Sharks tooth Grill wasn't an option for 340 or twisters it was standard in 71 and 72 ...I didn't know you could get power steering /AC with the four speed in 71... I bet that thing was all over the road with power steering oversteer and mix that with a 4 speed with a stout 340....ditch to ditch...your 72 could have been an early make with a forged steel crank engine and 10.5/1....Hell the cast crank low comp. ones still felt like your were driving on ice...360's never really gave me that feel unless it was built...w2
 
Please don't believe the 1972 hype that they got any slower. They had to lie about a lot back then. My farther bought a 71 340 4 speed with 3:55s He did have A/C, power steering/ brakes. Follow year I purchased a 72 340 3 speed standard with 3:91s
I ordered it without any options other than shark grill and stripe pkg.Power nothing. We street raced at least a dozen times and my 72 beat his 71 every time but once. We switched cars and same results other than once I beat him in his car and I still think he peddled it We never ran his at the track but I made a few passes with nothing but slicks and best was 13:71 @ 106mph.
72's were dogs. 73's were worse. All stock 72 even with slicks 106 you wish. I owned 71's and 72's. Unless as said above you got a 71 motor.
 
hi guys ! i wanted to know what is the best time ever recorded for a 340 duster or demon .. bone stock ... i know that they used to do the quarter mile in 14 sec but a lot of people said to me that a lot of was capable to enter the 13 sec range ???

thx
In summer of 71, My low-mileage, pure stock, 70 Dart, 4-speed and 3.55s, stock 268/276/114 cam, went;
98@14.4, (257hp by the Wallace)
on those Polyglass roller skates,
at 3330 pounds..
floating the valves at 5400.

45 years later, my 360 annihilated that with a 270/276/110 cam; Went;
106@12.9 (357hp, by the Wallace)
at 3650 pounds, still with street tires, a 4-speed, and 3.55s. Pulling to 7000.
best of one run lol,
 
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