340 4 barrel and 340 6 barrel: were they really UNDERrated?

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The thermoquad was a shot in the arm for the 340. The 71 high compression TQ equipped 340 is the high water mark as far as I'm concerned. I would seriously doubt the six pack actually made any more power
 
We have raced both of the a lot with stock intakes and flowed them.

The 6 Pack manifold on the 340 is absolutely worse.

It looks like an elephant stepped on it or it was grafted onto a
4 Barrel manifold as an afterthought.

However, that being said the 6 pack setup is only somewhat worse
in performance. But it is in most cars factored a Higher HP that is
in my opinion really not merited.
 
GTX JOHN said:
A bit of clarification for all. When I say stock asut
produced, everything is optimally tuned. We had
unlimited chassis dyno times. We properly adjusted the
timing curves for power and the carb. jets and accelerator
pump circuits. All original parts as produced BUT very well
tuned with plenty of Dyno time. The alignment, ride height
and pinion angle were all looked at and adjusted. When you
bought a new car back then, everything was literally all over the
place and needed looked at.

The "Beach" Track in Long Beach would actually have near zero
or sometimes even better (Mineshaft) Density Altitude on occasion
and was generally great (Unless Humidity was high sometimes).

We all raced Stock/SS back them and weekly brackets at several different
California tracks most ever week. There might be a possibility that our
skill sets might be a slight bit better than a newer driver.

I am was not trying to brag about anything, just answering the
posters original question to the best of my recollections. I was there
and racing since the early 60s. You can take or leave anything I say.

I live my life strictly for an audience of ONE (He is looking down on all of us)!
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Did you block the heat cross over ports on the intake manifold and remove or disable the heat riser in the passenger's side exhaust manifold? I would have.
 
NC Engine Builder said:
The thermoquad was a shot in the arm for the 340. The 71 high compression TQ equipped 340 is the high water mark as far as I'm concerned. I would seriously doubt the six pack actually made any more power
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Funny, that`s how my 69 engine was set up when I bought it. I still have that factory spreadbore setting out in the garage collecting dust.
 
RustyRatRod said:
It couldda been. About the first half of 72 still had the forged crank and good compression.⁸
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nutz said:
Not sure of the #s
But they all had a/c leather power everything
I have a 06 audi a8 cant get the title for it
Was thinking to strip it and let the kid race it
All alloy body and frame
320 hp v8 and allwheel drive
And it it blows i junk it
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Not sure about A8, but a couple yr earlier Audi had intercoolers, mounted low in front of front wheels. I havent seen one, but pics look like they might fit my 65 Barracuda in the same location, since no room behind grill, if i duct them properly. Was A4 station wagon model I saw.
 
Swinger 340 said:
That explains it.
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That worn out old trope again!
Nah! Some of the smartest people I've ever known smoked it.
And living in Florida you learn the right terps can help you.
One can even suppress hunger and you can lose weight, one terp can ease symptoms of asthma. But that's another area for research , I never read which terp that was, and some probably don't help.
 
Woody500 said:
Not sure about A8, but a couple yr earlier Audi had intercoolers, mounted low in front of front wheels. I havent seen one, but pics look like they might fit my 65 Barracuda in the same location, since no room behind grill, if i duct them properly. Was A4 station wagon model I saw.
Click to expand...

Woody500 said:
That worn out old trope again!
Nah! Some of the smartest people I've ever known smoked it.
And living in Florida you learn the right terps can help you.
One can even suppress hunger and you can lose weight, one terp can ease symptoms of asthma. But that's another area for research , I never read which terp that was, and some probably don't help.
Click to expand...
You are confused, man....This is a topic about stock 340 engines, not Audis or marijuana....
 

My car now weighs 3045 and it took a BUNCH to get it to that weight. All CI small block, 904/8 3/4” manual steering. With about 3-4 hundred lbs in lighter stuff. I own scales and weigh it more than I weigh myself.
 
340sFastback said:
Did you block the heat cross over ports on the intake manifold and remove or disable the heat riser in the passenger's side exhaust manifold? I would have.
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Not when they were completely stock with just tuning.
However, absolutely when we began actually racing them
seriously. The rattle made me crazy on the heat riser and it
is wired open on my son's 18,000 miles 340 Duster survivor/
 
Ya Know:

We race our 340 cars in D/SA or
E/SA because they are rated all the way up
to 314HP in NHRA from 275HP. That means we race early
396 Camaro/429 Mustangs/ 455SD Firebird/440
Darts = HEADS UP. All Big Block muscle cars from
our era. Every one of them Bonafide at least 13 second
or better cars in the hands of competent racers.

We routinely beat them and that is where we got all
our 50 Class Wallys!

Jon is racing for another one in his 71 340 Moulin Rouge
Duster in Superstock this afternoon.

Feel Free to dispute this too.
But it is all on the record and researchable
like everything else I have stated!!
 
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I could not care less about what you think of me.
Are you still insisting that a production 340 only
runs 5200/5400? If so, you are an absolute idiot!

Sorry I forgot about the cheater camshaft in the 11.88
National record car. It is stock lift but optimized duration.
It was a long time ago and I apologize for the oversight.
It was not deliberate and I set the record straight.

In my opinion if all the parts and pieces are as delivered,
they can certainly be optimized and tuned to best available
performance and are still stock parts.

Tony (RIP) was my good friend and so are his daughters.
I still see and do my best to help his daughters every opportunity
that I get. You sir do not speak for him and never have.

You are throwing out the baby with the bath water on understanding
my statements. They numbers on the `11 and 10 second cars are
clearly with some modifications and just to illustrate the potential
of the 340 with basic modifications of the stock parts in line with
the discussion. The 13's runs by my friend's and my Dad's
car are absolutely correct = I was there to see them and remember
then well. A stock part can be adjusted and still a stock part in my opinion,
you are welcome to disagree with me on that. What the Hell do I have to gain
by fabricating any of these things I have posted.!!!


I come on this site primarily to try and help out people that may have less
experience with the Mopar hobby.

BTW: If you Google "John Irving Racer"
You can see some of my cars and their performance
that I talk about on here.

May I have you name if you are willing to divulged it on this site?

If the majority of the folks on this forum agree with you guys that I
am an egotistical braggard = Kindly, just give me some feedback and I withdraw
from posting anything about this stull, except for selling my deceased friend's parts.
 
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So, an otherwise stock 340 Demon can run 11.88 at 113 with a cam swap, gear, and slick? My little 340 is really jealous and I wish I had that magical touch.
 
I read stories in past about stamped steel factory rockers having wide range of tolerances. So racers would get several dozen rockers, find the set with the biggest lift, and run those to get a performance edge. But still technically stock parts.
 
Years ago I switched from the stock stamped steel rockers to 1.6 aluminum ones and noticed that my cranking compression numbers all got closer together in numbers. It was as if a true ratio on each rocker somehow equalized the low numbers.
 
crackedback said:
You COMPLETELY miss the point. Not a big deal.

This isn't about racing it's about saying a factory OEM as delivered 340, off the showroom, never had a wrench turned on it, car running 13.05... not happening

NO MODIFICATIONS.... YOUR WORDS.

That is a LIE. Not owning that says EVERYTHING I need to know about your character, credibility and integrity.
Blovate about NHRA, record books and anything else. It's not relevant one iota to the base claim YOU made.

Not speaking for Tony, just know how he would respond from the 15+ years I knew him. You don't speak for him either.
Th
Carry on.

I'm out.
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I am still waiting for you to reveal your name?

That Demon never had the short block removed from
the engine bay when the first time it set the NHRA National Record.

We also ran a 360 Duster in Stock Eliminator in 1975
with an Automatic that ran 12.40 with the block never removed
from the engine bay back then either.

I really do not care about your opinion or what statement you
pull out of thin air or anywhere else you pull them out of as you
have no credibility. You just hurtle insults and personal attacks without
a shred of documentation.

Read my post again = I never claimed to speak for my friend Tony
or anyone else ever. I speak only for myself and here from my own experiences
in life.

Again, I was there back then, and I still am here now living my Dreams and
helping everyone else live theirs when I can.

To Summarize:

Those that can DO, those that CAN'T hoot on the sidelines
and throw mud and hide behind their keyboards.
 
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this whole thread is starting to read like the comments section of a recipe:

i didn't have cumin so i used tarragon instead and didn't have chicken so i used beef, my oven was broken so i used my microwave and everything came out awful. this is the most terrible dish i've ever made and i don't know how anybody thinks that it's good. even my children laughed at me and now my husband won't talk to me.
 
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