My cousin use to race late model and the track was dynoing engines for coming up with rules when bring in Chev crate engines, and said they had a hard time making under 400 hp with the Mopar to try and match the Chev crate.
340 4 barrel and 340 6 barrel: were they really UNDERrated?
- Thread starter Kern Dog
- Start date
-
340sFastback
Well-Known Member
Most '68 - '71 A bodies ran mid to low 14s bone stock. A low option car, 4 spd, 391 at sea level altitude good driver all the stars aligned maybe a tail wind can dip into the 13s. If someone ran low 13s stock 340 A Body that is highly unusual and ppl will struggle to believe it. Not saying not true but that not generally how they ran. Stock 2 1/4 crush bent choke exhaust, 1 5/8 inner diameter chrome exhaust tips, giant pinch in head pipe for torsion bar. Stock had less then ideal carb jetting and dist curve. Valve in pass exhaust manifold causing excessive heat in intake manifold ect ect ect..
furrystump
Well-Known Member
- Joined
- Nov 13, 2004
- Messages
- 2,611
- Reaction score
- 2,345
So I ran my bone stock 340 Formula s once as a kid. it ran 98 mph and weighed 3650. The calculators put that over 300 hp at the crank.
mopowers
Well-Known Member
I don't doubt the a 340 Demon ran 11.88 at 113. What's hard for me to understand is how it did it bone stock with only headers, gears, and tires at 3100 lbs (w/ driver?). It makes my little 340 Dart feel grossly inferior.
70SwingerGuy
Long Haired Freaky Person
That is sa-weet dude!!
because he doesn't preview or edit his posts. i'm guessing he's posting in BB code and he adds an /s somewhere and winds up not capping it.
whatever, it's not like there was pertinent information anyway.
He asked about a particular car and a run that we made.
I also posted the numbers that I recollect from when our
340 cars were Brand New and totally stock except for tuning
of course. Also, the first hand results that I had back then in
my experience after stages of modification.
I am responding for to the question asked by the Original Poster
hopefully to be a benefit to my friends on this site.
It really aggravates me when someone says that the 340s were
only good for 5200/5400 new. Mopar in the ads advertised them
at " 6000 RPMS for under $3,000". They were conservative as they
had to warrantee they for 5 years/ 50,000 Miles.
Ya know:
I was there and owned/raced the 340s and every
other Moar back then. I even owned a couple of Dealerships.
I still do race them and I am even right now at the track racing
three at the Nationals today and am between rounds.
I love A Bodys as much as anyone in the World and
particularly the early 340s. It pisses me off no end, when
I see misinformation disseminated on these cars. I will set
the story right every single time.
I do not ever claim to be any big expert or a great mechanic. Often
I ask for help and advise from my many friends on this site and benefit
from it = a Lot.
However, I have been around and raced various Mopar for way over
60 years and it is my chosen Hobby and I do know a few things about
them.
I am sorry, in review my posting today (Tired last night) I failed to include thatI don't doubt the a 340 Demon ran 11.88 at 113. What's hard for me to understand is how it did it bone stock with only headers, gears, and tires at 3100 lbs (w/ driver?). It makes my little 340 Dart feel grossly inferior.
the camshaft was "Legal Stock Specs" but was a Competition Cams Cheater cam that
checked legal but was a WAY higher rate of opening. These trick camshaft back them
really helped the power out. The car was completely torn down after the record run and
adjusted to be Stock legal (They were very much tighter on the rules back then stock was muh
more really stock).
Anyone who has access to an old National Dragster Circa 75/77 can look it up as the records were
published ever single week unlike today where Dragster is once a month if you are lucky and records
are no long printed in them
Last edited:
Ironmike
Well-Known Member
Waaaay back in the late 70's, I was racing my Chevelle every Friday night at the old Heidleberg track, not 20 miles away. One of "our gang" was a couple years older than us and more experienced. He ran a red 70 Duster bone stock, other than headers and a "shift kit". I don't remember what rear gears, but I know he ran L60 bias ply cheapo tires on the back.
That car was so consistent it was ridiculous, and it ran 14 teens. Every Friday night, pass after pass.
And get this: He always ran with his spare and jack in the trunk. I should add RIP Nick. Loved that guy.
That car was so consistent it was ridiculous, and it ran 14 teens. Every Friday night, pass after pass.
And get this: He always ran with his spare and jack in the trunk. I should add RIP Nick. Loved that guy.
Last edited:
rklein383
Well-Known Member
- Joined
- Dec 2, 2005
- Messages
- 2,296
- Reaction score
- 2,066
It probably begins when you get up in the mornin. LOL
Maybe there's a sticky button on your keyboard.
I know you say all that tongue and cheek, but I can remember well some cars were just plain faster and quicker than they shouldda been. @krazykuda Karl can attest to it, as well. He worked on the line for Chrysler for a while. He has some stories to tell. In fact, I got one. I had a friend whose father had a 1970 Impala four door. Just a family car. BUT it had a 300 horse 350 in it. Most were garden variety 250 or 270 horse, but this one got the 350/300. Every now and again David, my friend, would be granted use of the car. We'd go out terrorizing people in it. It was the ultimate sleeper. Four door and that GM mint green. We whooped up on many an unsuspecting opponent.
Then, David got a 69 Camaro. 250 horse 350. So one day we were over at David's and he kept looking back and forth at the Impala first, then the Camaro. The family was going on a long weekend vacation, but David, since he now was 18 and had a job, was staying home. Yup. We did an engine swap between that Impala and David's Camaro. The old man never knew the difference, because he never romped on the Impala to really know what it had. But David's car was now a holy terror. Now I fully admit, we were young and stupid. What was actually a 300 horse motor "could" have seem like more "JUST CAUSE" we were young and stupid. But both cars, first the Impala and then the Camaro claimed LOTS of victims "WE JUST KNEW" should have bested us, but didn't.
I wish you luck, my friend!
Jim Lusk
Well-Known Member
What I have read is that guys who worked Chrysler's dyno rooms claimed not one 340 came in under 320hp. NHRA factored them to 310hp. Guys on the street said they ran like 350hp 327s. I have also seen tests where pretty much everything else Chrysler sold, with the exception of the 426 hemi, was pretty close to advertised.
Now, consider marketing and other cars/engines in fleet along with racing class and insurance rates. Who would have bought a 383 Dart if the 340 was advertised with more horsepower? Who would have bought a 383 RR/Super Bee for the same reason?
Now, consider marketing and other cars/engines in fleet along with racing class and insurance rates. Who would have bought a 383 Dart if the 340 was advertised with more horsepower? Who would have bought a 383 RR/Super Bee for the same reason?
most the new 70 340 a bodies ran low 14 seconds back in the day , some were fast some were dogs . Me and my buddy bought identical darts , his was always a bit quicker no matter which one of us drove , we switched cars a few times no matter what his was faster . That is just the way it was back then
Funny how now days a normal family sedans are a 14 second car, My Avenger R/T supposed to do mid 14's with it's 3,600 lbs weight. Too bad these 3.6l engines weren't cheap and easy to install in a A Body since there's a ton of them.
Having owned my '68 340 FS FB 727 3.55 rear Cuda since June 1969, I know a fair amount about how it ran. I purchased it with 17000 miles on it and the previous owner said it turned 13.7's at 102. I took the car to all the strips in the LA/LB area, especially OCIR, and turned in the 13.50's to 13.60's at 104+ all the time. With 3.55 gears, I went through the traps at about 6200 in second or shifted to 3rd at 5800 but turned the same times. With gears and better tires, it probably would have been in the 12's.
The Mopar Bible had a ET/Speed calculation and with the weight of the car and driver (i weighed 175 back then, not now), the calculations showed about 320 HP which is consistent with other reported values for a stock older high CR 340.
Being an A727 car, it shouldn't have had the 4sp cam, but the way the engine ran, that wouldn't have surprised me. The car was an earlier build of December 7, so how knows what they did back then.
All I can say is that a large number of 340 Dusters and Darts in SoCal at that time could also turn 13.70's to 13.90's if the driver knew what he was doing. So, my 340 was a little faster than most, but not by a lot.
I saved a bunch of timing slips from OCIR and attached a photo to show that this was real. No 0 to 60ft times back then, bummer.
The Mopar Bible had a ET/Speed calculation and with the weight of the car and driver (i weighed 175 back then, not now), the calculations showed about 320 HP which is consistent with other reported values for a stock older high CR 340.
Being an A727 car, it shouldn't have had the 4sp cam, but the way the engine ran, that wouldn't have surprised me. The car was an earlier build of December 7, so how knows what they did back then.
All I can say is that a large number of 340 Dusters and Darts in SoCal at that time could also turn 13.70's to 13.90's if the driver knew what he was doing. So, my 340 was a little faster than most, but not by a lot.
I saved a bunch of timing slips from OCIR and attached a photo to show that this was real. No 0 to 60ft times back then, bummer.
THIS stuff is great to see....old timers that raced these when the cars were only a few years old!
This is great stuff! Thanks so much for sharing!
-
