article from 2017... How Bad Did Mopar’s 340 beat Ford & Chevy?

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Reminds me of an interview I read with one of the dyno techs from Chrysler in the 60s and 70s, he claimed that he had never seen a 340 make less than 320 hp.
 
The 340 in this article is not a 100% stock engine. Lightened internals, honing plates, bowl hogged, roller rockers, etc. All that adds up to more power.
I'm a fan (and owner) so not bashing.
 
For starters, if the 4bbl engine in the pic was used for the test, then it is not original specs because THAT engine has an AFB carb on it, original had an AVS.

The true test was back in the day. No 'rebuilding', no 'tuning'. PHR magazine pulled the small block engines from showroom cars & tested them to see if they made the adv HP. Results were published in Feb 69 issue, & I have the result page.

340 was the only engine that made it's adv rating of 275, but actually did better & made 295HP!!!

It also revved freely, was smooth & docile no bad habits.

Also tested: 350 Chebby, Olds W-31, Pontiac 350 HO, 351 Ferd. Here are the numbers. factory rating, then actual measured hp. 300, 240; 325, 280; 325,255; 290,210
 
Well, it wouldn't have beat the 1970 LT1 350 in a Nova, Camaro or Corvette. 370HP and 380LB FT available with a 4 speed and up to 4.56 gears. As long as both drivers were about equal in ability, that LT1 was a tough customer. 11:1 compression and a solid cam. Disagree all yall want, the 340 was just not a match for that.
 
A few near stock 340's I have had never really seemed all that fast from the seat of my pants, but beat nearly everyone I street raced in NJ in the 70's including a 71 LT1
Corvette more than once. 340 Duster had only headers ,Vette was stock walked away from it. NO 350, 351 I ran a could beat the Duster, but there where ALOT
of poorly tuned cars back then running around with mismatched aftermarket parts.
 
RustyRatRod said:
Well, it wouldn't have beat the 1970 LT1 350 in a Nova, Camaro or Corvette. 370HP and 380LB FT available with a 4 speed and up to 4.56 gears. As long as both drivers were about equal in ability, that LT1 was a tough customer. 11:1 compression and a solid cam. Disagree all yall want, the 340 was just not a match for that.
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I read that the corvette ran 14.30's @101 and a 70 340 would do 14.70's @94 not bad for a much heavier car.
 
I built a LT1 back in the 70's for a friend, it was his dream motor. Early 70's 4 speed Camaro high gears. Chevy NOS short block, angle plug iron heads, crummy valve job by his uncle, insisted on using the worthless plastic toothed cam gear and OEM HEI distributer. My 273 would beat it. A couple years later, I saw it again. He had given it to a cousin. You could hear the valves leaking, an absolute dog. A 170 slant six would beat it. The LT1 might be fast in a race car, with race gas, tuned to the max, but not fast on the street with pump gas.
Many 340 cars were faster than 14.7, my 71 Duster included.
 
66jim said:
A few near stock 340's I have had never really seemed all that fast from the seat of my pants, but beat nearly everyone I street raced in NJ in the 70's including a 71 LT1
Corvette more than once. 340 Duster had only headers ,Vette was stock walked away from it. NO 350, 351 I ran a could beat the Duster, but there where ALOT
of poorly tuned cars back then running around with mismatched aftermarket parts.
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The 71 LT1 was a completely different animal. 9.3:1 compared to 11:1 from 70 with a much smaller solid cam. Plus a lot of people back then "said" they had an LT1. lol
 
thesiren74 said:
I read that the corvette ran 14.30's @101 and a 70 340 would do 14.70's @94 not bad for a much heavier car.
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The 70 base Corvette was 14.9. The 70 LT1 was not the base. The LT1 for 70 in the Corvette was clocked at 14.1 and in the Camaro was 13.88. These times were both with the optional 4.10 gears. Either would have been difficult for a 340 Dart to come around, but not impossible.

If any of yall did it, either the driver didn't know how to drive, or it was not a real 70 LT1. I had a neighbor growing up who had a lot of thee cars and just because they were Chevys, they weren't slow. Yall can keep living in that fantasy land if you want, but there were badass cars that weren't Mopars.
 
66fs said:
I built a LT1 back in the 70's for a friend, it was his dream motor. Early 70's 4 speed Camaro high gears. Chevy NOS short block, angle plug iron heads, crummy valve job by his uncle, insisted on using the worthless plastic toothed cam gear and OEM HEI distributer. My 273 would beat it. A couple years later, I saw it again. He had given it to a cousin. You could hear the valves leaking, an absolute dog. A 170 slant six would beat it. The LT1 might be fast in a race car, with race gas, tuned to the max, but not fast on the street with pump gas.
Many 340 cars were faster than 14.7, my 71 Duster included.
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Absolutely correct. There were standouts in every make. I've always wondered why. Maybe they got some extra super tuning? Who knows. I had an original 73 340 Rally Charger in high school totally untouched with 79K on the clock. That car would spank everything but a 70 Camaro with a hot 400 and an original LS6 454 Chevelle. I routinely cleaned the clock of another guy who had a 350HP version of the 396 in a 70 Chevelle. Pissed him off.
 
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RustyRatRod said:
The 71 LT1 was a completely different animal. 9.3:1 compared to 11:1 from 70 with a much smaller solid cam. Plus a lot of people back then "said" they had an LT1. lol
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This particular LT1 was purchased by owned by a rich kid in 1974 was an original low mileage vette (LT1 hood and all). He was pissed after my ragged Duster beat him up.
Soon after he blew up the LT1 and got another "built" 350 put together by a local
speed shop. I did not have a chance to race it then because that motor was blown
up as well. The 71 LT1 had better flowing heads than the 70 it was "rated'" at 330hp.
IMO 350's where very over rated back in the day, and I do not trust GM and their
magazine propaganda machine with ringers sent as press cars.
 
RustyRatRod said:
Well, it wouldn't have beat the 1970 LT1 350 in a Nova, Camaro or Corvette. 370HP and 380LB FT available with a 4 speed and up to 4.56 gears. As long as both drivers were about equal in ability, that LT1 was a tough customer. 11:1 compression and a solid cam. Disagree all yall want, the 340 was just not a match for that.
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I have to disagree on that claim, I have seen a stock and when I say stock, I mean stock 69-1/2 340 powered Duster 4 speed with 3.55 gears, right down to the factory exhaust all the way back, burn a LT1 4 speed NOT stock. Repeatedly, the guy just could not accept it. He insisted on running over and over every time using a different excuses for loosing. That very same day I watched that Duster smoke a built Ford 460, same deal over and over along with a list of other cars from all the makers try to shut that 340 down or blown it up, just didn't happenn. That Duster even had stock steel rally rims, with radials on them in 1978. The 340 even had the factory valve covers, NO ONE had ever done any thing to that 340 not even give it a bath. Factory air filter housing which I later purchased from the guy after the little 340 basically died a few yrs later, from the notorious front bulkhead splitting along with the rings finally giving out. We were high school friends and I tried desperately to convince him to bring the 340 back to life somehow, even if it had a cracked block, there are ways to fix cracks that work if doe right. The filter housing had the vacuum trap door in the rear and I have NEVER seen another housing same as that one from MOPAR again. I used it on a 72 318 I built with ported heads and used a 69 hyd. 340 camshaft, then found a single plane cast iron 273 Commando intake which I removed the center portion of the carb flange(4 round ports) to increase the plenum, I did a list of other things to that 318 which had all forged parts from the factory, except forged pistons, the rods it turned out were the same part number used in the 360's of that yr. twice the weight of the earlier 318 rods. I put that engine in a 70 barracuda I had and proceeded to beat 1 W30, several 351 W's, there was 1 351 C I could never beat though, it was put into an old 51 Ford PU, that thing was just flat *** bad to the bone. I later replaced my 318 with a 440 and still couldn't out run that CPU. Anyway, my 318 smoked a LT 3 times one night and that guy called a liar insisting my 18 was a 60 until I jacked the car up so he could crawl under to look at the casting in the block, he wouldn't accept the stamping on the front saying I could have changed that. Funny thing is, I have seen roundy pounders change those too in an attempt to get around rules. I've kick myself for 40 years now for giving up that 18r to someone else along with all the other MOPAR stuff I have had since I was 16. Turns out MOPAR stuff is just so much more expensive than what any of the other stuff is and getting so hard to find anymore. You get what you pay for though. I've been bending wrenches for people over the western half of this country for over 40 yrs and been a MOPAR or NO PAR guy most of it until it just got nearly impossible to get my hands on quality bodies to play with.
 
thesiren74 said:
I read that the corvette ran 14.30's @101 and a 70 340 would do 14.70's @94 not bad for a much heavier car.
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The 71 Dusters were even faster:


Its average elapsed time was 14,07 at 100.09mph.

DRAG RACER RONNIE SOX IN CAR LIFE 1971


And this I don't remember where I've found it originally:


...best time being a 14,08/97mph. Those times were accomplished with the high-revving340 mated to a console-shifted Torqueflite trans.

DRAG RACER KEN QUIGLY 1971
 
- Marvin - said:
The 71 Dusters were even faster:


Its average elapsed time was 14,07 at 100.09mph.

DRAG RACER RONNIE SOX IN CAR LIFE 1971


And this I don't remember where I've found it originally:


...best time being a 14,08/97mph. Those times were accomplished with the high-revving340 mated to a console-shifted Torqueflite trans.

DRAG RACER KEN QUIGLY 1971
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Those times were as slow as snails compared to more modern times only because tire tech was not what it is today. I remember watching and driving some of these cars back in the late 70's and through the 80's running much faster with better tires and suspension improvements.
 
Were the other cars comparably priced? I seem to think the 340 cars were highly competitive at less cost and that's what would chap a Corvette lovers hide, paying the money and a guy with a less expensive car blows his doors off.:)
 
Dartswinger70 said:
Were the other cars comparably priced? I seem to think the 340 cars were highly competitive at less cost and that's what would chap a Corvette lovers hide, paying the money and a guy with a less expensive car blows his doors off.:)
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When i worked at my old body shop i went to pickup a customer's 75 corvette from the alignment shop and that thing was so slow i couldn't believe it! My 74 Duster with a 2 barrel 318 would've smoked that turd.
 
thesiren74 said:
When i worked at my old body shop i went to pickup a customer's 75 corvette from the alignment shop and that thing was so slow i couldn't believe it! My 74 Duster with a 2 barrel 318 would've smoked that turd.
Click to expand...
They were pretty gutless in those years, I remember driving a few customers Vettes and thinking what a gutless turd.
 
missing linc said:
Reminds me of an interview I read with one of the dyno techs from Chrysler in the 60s and 70s, he claimed that he had never seen a 340 make less than 320 hp.
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I believe that. I was always curious how a chev 350/300 with less compression, less heads and less camshaft less intake would beat out thee 340
Insurance reasons??
 
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And................

Roger Huntington's American Super cars book. His testing & magazine tests. He would estimate the actual [ net ] HP from 1/4 times, gearing, weight etc.

340 six pack, 3.55 gears, 14.5 @ 99. Adv hp, net 310.
350 Z/28, 4.10 gears, 14.5 @ 99. Adv hp 360, net 320.

Another lot of his tests...
'68 340 Cuda, 3.23, 14.9 @ 95. 275, 290 hp
'70 340 Cud, 3.54, 15.0 @ 95. 275, 290 hp.
'67 350 Camaro, 3.55, 15.8 @ 91, 295, 230 hp.

Pretty obvious who is telling porkies...& it is not Chrysler.
 
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