340 cam specs?

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and the 204-214 cam at 278@.004 is almost the same as the 340 in duration @.004 and lift (but the shape is different)
the "classic" 204 closes a little earlier due to the closer 112LCA (compared to the 340 114LCA)
see post 19 this thread for 204 specs
Camshaft suggestions
Edelbrock has sold lots of these- mostly to give the chevies a chance :)
the 279 numbers posted above should be real close
and just as sad
 
AJ/FormS said:
Sounds about right.
And that's about what I remember about my 340s: with a manual trans and 3.55s, I always had to use the flywheel to get moving, and mine had to be wound up to pull. And my stockers (69 and 70),quit pulling around 85mph. Shifting to Fourth was sorta dead. Still, the stockers went almost 100 mph in the quarter.
Those VPs suck. I always had to keep the Rs on the cam; the right hand was always on the shifter. It was better after I got the 4.10s,lol.
But I've only got about 10 years driving experience on three of those early models after which I switched to 360s.The Dart was peppier than the BarracudaFB, I guess because of the approximate 300 pound difference in the chassis weights.
Click to expand...
A lot folks like @VOETOM are happy with their 340 cams in a 340. Granted the one he mentioned is not the same as the one we're talking about. If my dynomation comparison is correct, it would be be even less peppy (less torque) in the same situation.
It looks to me like using an above deck piston was critical, and heads with smaller than as-cast chambers could only help.
Pep could relate to other things too as you mention; everything from vehicle weight to idle circuit tune.
My take aways are: this cam needs compression, and there is big difference in V/P when using different seat to seat measurement methods. So the second must be considered, along with equivalent altitude when comparing.
Granted this is mostly for historical purposes, but I think its a useful baseline when people are looking to make changes.
 
Cam selection is such a goat screw. Most manufacturers use different specs for measuring so it's difficult to compare. Hell they probably copy a successful grind and measure it differently so it doesn't look the same. LOL
 
I like that Mike, a goat screw!
Along with that cam, I run the 91 truck cylinder head with big valves that were set up by one of the cylinder head guys at Chrysler and it has about 10.75:1 compression; it likes the cam even more.
Tom
 
FWIW. we can compare compression and V/P using of the auto vs the 4 speed cam as long we stick with using Chrysler's seat to seat for the comparison.
Altitude of 500 ft used, same as before.
4 speed Manual cam has Chrysler intake duration of 276 and assume installed at 112 (looks like it from the specs)
Static compression ratio of 10.0:1.
Effective stroke is 2.28 inches.
Your dynamic compression ratio is 7.56:1 .
Your dynamic cranking pressure is 149.21 PSI.
Your effective boost compression ratio, reflecting static c.r., cam timing, altitude is 7.46 :1.
V/P (Volume to Pressure Index) is 105

with more compression.
Static compression ratio of 10.75:1.
Effective stroke is 2.28 inches.
Your dynamic compression ratio is 8.10:1 .
Your dynamic cranking pressure is 163.55 PSI.
Your effective boost compression ratio, reflecting static c.r., cam timing, altitude, 8.00 :1.
V/P (Volume to Pressure Index) is 115
 
If I remember the 4 speed intake is "very similar" to the Auto exhaust and they got the 4 speed exhaust off the rack somewhere
Absolutely a goat screw
That's why for this thread we gave stock advertised 268 which is close to .008


advertised 279/289 SAE or .004 so compare with Crane/ Cam Dynamics and others that advertise at .004 like Summit
that's how we compared the 204-214 cam which is 278
The 279 calculations shown above give a much more accurate picture than using MOPAR's 268
also show why that stock cam loves compression it's basically a "280" class cam

you want to compare the Manual 340 cam you can directly compare with DC and Engle or just add 10 degrees for Crane and the "white box" camsso for DCL purposes let's call the 4 speed cam a 289-
 
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Wyrmrider said:
you want to compare the Manual 340 cam you can directly compare with DC and Engle or just add 10 degrees for Crane and the "white box" cams so for DCL purposes let's call the 4 speed cam a 289-
Click to expand...

With the power of a 220@.050, or less IIRC,
making the monkey motion really really long; how sad is that!
But back in 1970 when I got my first 340 car, man that was power!
But it was a trick...
Those E70-14 polyglass tires under it, were like rollerskates.
So even if you didn't have big power, you sure thought you did..at least I did, but I was only 17
Good thing we all had those tires so the playing field was mostly level.

My next cam will be a solid FT, no question about it.
 
I don't know if anyone's mentioned it and I'm not going through this ridiculousness to find out, but Oregon Cams has the 340 4 speed grind in stock. Thanks to a couple of forum members, they were sent an original and mapped it and now have the grind in stock. I think because of the way they had to do it, it came in like 2* different, but it's the same thing. @krazykuda Karl can shed a little more light on it, but if you need a 340 4 speed grind, they have it.

Now, continue on with the useless dick contest.
 
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RustyRatRod said:
I don't know if anyone's mentioned it and I'm not going through this ridiculousness to find out, but Oregon Cams has the 340 4 speed grind in stock. Thanks to a couple of forum members, they were sent an original and mapped it and now have the grind in stock. I think because of the way they had to do it, it came in like 2* different, but it's the same thing. @krazykuda Karl can shed a little mire light on it, but if you need a 340 4 speed grind, they have it.

Now, continue on with the useless dick contest.
Click to expand...

The custom grind 340 4 speed cam that I had sent to Oregon cams was a few degrees off on the one lobe, which they can bump back into position... The only other thing that was off on mine was it was .006" less exhaust lift which Oregon can't "fudge", so their clone can be made to the exact lobe centers and lobe center line, with full intake lift, and only .006" less exhaust lift....

I'm not sure if @dibbons had one made and which spec it was made to.... Maybe he can let us know if he got the "improved" one...
 
When Oregon cam delivers they deliver with a rather complete @ each lift sheet .002 to 300
post it up when you get it
Slantsix64 list got his what looks like a RT HR regrind. He is going to degree it in with a new 3 way timing chain and a offset key is needed as Oregon cams said on the phone that they had to grind it straight up to fit on the lobes but the timing sheet shows 4 degrees advance. We'll see soon
His thread is 318 budget build I need to take another look too
I think he posted the RT cam card from Otegon\see

Aj said on the stick shift cam
With the power of a 220@.050, or less IIRC,
making the monkey motion really really long; how sad is that!

Pretty sad even for a resto gut If a 340 was blueprinted to a true OEM compression you are looking at more than today's pump gas
We did not have the springs back in the 60's so cams were made long, slow and low

krazy I thought that exhaust lobe was from the 383 parts bin - but it's been a long time. One of the big detroit grinders used to make it- I think CMC where are they now?
 
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I've posted this befoe but here's a dyno sheet for a lower compression motor
has the torque curve I like for daily driver
Owner Maurinzio said
What surprised me was the extent of the power band: 90% of peak TQ from the bottom of the chart (2800) to 5100.
363 HP at 5000. 90% of peak HP from 4200 to the top of the chart (5200).
The HP peak had a bit of a nice mini-band, too. I bet the thing would have had 350 through 5500 or so.

upload_2019-7-6_17-52-55.jpeg
 
AJ looks like you are up a couple of sizes the one used on the run I posted is 246 @.008 256@.006 264@.004 and 202 @.050 any idea what yours is @.004?
any idea why the dip in the torque curve?
Hughes E3038AL
INT .515" EXH .535" (1.5) INT .549" EXH .571" (1.6)
230 237 @.050
276 286 @.008
110 LCA
8 BTC 42 ABC 51.5 BBC 5.5 ATC 13.5 ovlp @.050

ENGLE?
 
Not measured at .004.
Probably Engle; I recall it was in a plain white box with a Hughes sticker on it. but I sorta recall seeing Engle somewhere on the cam, not sure.
That curve comes from the Hughes site. I built a very similar build, except
My;OOTB Eddies,to their stage II 596s
My; 10.85 Scr to their ,unspecified, but you can see for yourself by the curve, probably not close to the borderline
My; AirGap/ Holley 750DP, to their Torquer II/ Eddie 750
And the rest is mostly a wash

Can't speak to the dip. I wondered about it too, but since it ain't there on mine in real life, I chalked it up to the AVS type carb, or the tip-in, but IDK
I can't speak to the torque peak being so high either, and so close to the power peak; that look's wonky.
But I can tell you that on mine, I can floor it from cruising, anywhere between 45 and 55 mph in 6.06 effective road gear, and it breaks the 295s loose. This with a 4-speed in 1.92 second gear, and 3.55s, with 27" tires. So 50mph would be 4240 rpm. It's a honey of a combo, altho, it's pretty hard on gas. Once it's spinning, it spins ; some say still hazing the tires at the top of the Eighth, with 325/50-15 BFG DRs.I didn't see it, but the tach was stuck on 7000 the whole way; I thought the clutch was slipping. Hyup a real sweetheart street combo.
 
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krazykuda said:
The custom grind 340 4 speed cam that I had sent to Oregon cams was a few degrees off on the one lobe, which they can bump back into position... The only other thing that was off on mine was it was .006" less exhaust lift which Oregon can't "fudge", so their clone can be made to the exact lobe centers and lobe center line, with full intake lift, and only .006" less exhaust lift....

I'm not sure if @dibbons had one made and which spec it was made to.... Maybe he can let us know if he got the "improved" one...
Click to expand...


Ok we were discussing the 340 4 speed cam in the coffee thread and it was suggested that I post my info here...

I bought a set of custom ground 340 cams from a member here many years ago and have been saving them on the shelf... Another member asked if I would mind sending them to Oregon Cams so he could have one made, so we sent my cams to Oregon Cams and Ken Hoard measured them...

He can now make one of the 340 4 speed cams off of the "layout" that he did on mine... One of the lobes was a couple degrees off, but he can bump it to get right on the spec... The only area mine was off, was the exhaust lift was .006" less than the factory spec...

Here's the layout from Ken Hoard of the stock 340 Automatic cam that was custom ground to the specs:

340 Auto Cam Data KH 02.jpg



Here's the layout from Ken Hoard of the stock 340 4 speed cam that was custom ground to the specs:

340 4 Speed Cam Data KH 02.jpg



Here's my degree info compared to the Ken Hoard data:

Oregon Cam Layout 340 4 Speed.jpg


340 4 Speed Cam Factory Spec 02.jpg


Ken Hoard is able to bump the one lobe that is off to the proper location to match the 340 4 speed cam specs from the service manual if anyone is interested in one, contact him at Oregon Cams and he can make them now... This may be the closest to getting the 340 4 speed grind so far...
 
Krazy thanks so much
but why anyone would run either of those long duration low lift grinds today IDK
Just a quick comparison with Jones, Lunati, Howards 256 cams for the first one
where they show more area with 10 degrees less seat
or with the same 265ish
HM2203372A 267 244 220 140 0.337
and Comps HL for the second (or 276 Lunati Voodo and many others)
at 275 Howard HM2283525A 275@.006 252@.020 228@.050 148@.0200 0.353
compare the @200
 
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Wyrmrider said:
Krazy thanks so much
but why anyone would run either of those long duration low lift grinds today IDK
Just a quick comparison with Jones, Lunati, Howards 256 cams for the first one
where they show more area with 10 degrees less seat
or with the same 265ish
HM2203372A 267 244 220 140 0.337
and Comps HL for the second (or 276 Lunati Voodo and many others)
at 275 Howard HM2283525A 275@.006 252@.020 228@.050 148@.0200 0.353
compare the @200
Click to expand...
Sometime there's rules.....
My interest is what the SAE .004/.006 numbers were so I can plug them into the dynomation program.
This all started for me when I noticed the relatively expensive program did not spit out a hp curve with the same shape as real dyno tests of the factory engines.
In other words, I want a legit baseline for the program.
 
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mattax
I've camdoc ed many cams
let me know if i can help on the .004 vs .006 issue
MP and Engle are around and it does make a big difference
NM has addressed this issue and there are comments on asymetrical cams recently
 
Wyrmrider said:
When Oregon cam delivers they deliver with a rather complete @ each lift sheet .002 to 300
post it up when you get it
Slantsix64 list got his what looks like a RT HR regrind. He is going to degree it in with a new 3 way timing chain and a offset key is needed as Oregon cams said on the phone that they had to grind it straight up to fit on the lobes but the timing sheet shows 4 degrees advance. We'll see soon
His thread is 318 budget build I need to take another look too
I think he posted the RT cam card from Otegon\see

Aj said on the stick shift cam
With the power of a 220@.050, or less IIRC,
making the monkey motion really really long; how sad is that!

Pretty sad even for a resto gut If a 340 was blueprinted to a true OEM compression you are looking at more than today's pump gas
We did not have the springs back in the 60's so cams were made long, slow and low

krazy I thought that exhaust lobe was from the 383 parts bin - but it's been a long time. One of the big detroit grinders used to make it- I think CMC where are they now?
Click to expand...
CMC is alive and well and making millions of OEM cams and performance cores for most of today's cam makers.

The Gen 3 Hemis have CMC cores, I just sold a Chevy Comp cam on a CMC cores and many of Mopars small block cams are from them
 
[QUOTE="Wyrmrider, post: 1972571793, member
We did not have the springs back in the 60's so cams were made long, slow and low

^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
This !!!!!! They made power with duration. I worked at the speed shop/parts store back in the 70's. (Back when Comp Cams was new on the block) 3/4 race was "the "thing. LOL
 
toolmanmike said:
[QUOTE="Wyrmrider, post: 1972571793, member
We did not have the springs back in the 60's so cams were made long, slow and low

^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
This !!!!!! They made power with duration. I worked at the speed shop/parts store back in the 70's. (Back when Comp Cams was new on the block) 3/4 race was "the "thing. LOL
Click to expand...
Do you remember Comps original name?

I visited their operation on Democrat Rd in Memphis a few times in their early years....looked like a few Berco grinders and some other older machine tools. Advertising has done a lot for them.
 
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