340 cam change

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When my time comes , probably this winter Im taking Rusty's advice... 1968 340-4 speed cam from Oregon Cam..
That's what I bolted into my fairly stock 340 build (9.75:1 compression, stock manifolds, Eddy intake and AVS 650 carb, 3.55 4 speed). I've run it on the test stand...not much of a lope but sounds good. I'm sure I could get more out of the engine but that wasn't the point. If I recall correctly its installed 2 degrees advanced.
 
When my time comes , probably this winter Im taking Rusty's advice... 1968 340-4 speed cam from Oregon Cam..
I have said this before. It's not all about the cam, it's the complete setup. My 69' Dart (in photo) has a 4 speed and I install the 68' 4 speed cam when I rebuilt it in 88', from DC as a Hemi grind. All other items on the motor, air cleaner to exhaust tips are factory. I also rebuilt my 72; Dodge with a 70' 340, but installed the auto cam, also a DC Hemi grind, in 89'. The van seems to run stronger. Holley 650, single plane intake, Accel distributor with super coil, solid copper spark plug wires, appliance 2 1/2" chambers with 2 1/2 pipe into walker turbos, coming out in front of rear tires. 295 T/A radials. 355 rear gear on 1.5 ton springs. Stock converter in a HD 727 with some internal adjustments. I always keep my eye on the fluid color and change it around every 50,000 miles with type "F" fluid.
 
We have both 440 A-bodies and a 340 A-body. While I love the 340 and it is likely not a lot slower than the 440, the 440 pulls light a freight train on the low end which the 340 really will never do without a lot of gear and then wouldn't be fun (for me) on the street.
 
i think more than one have found the old melling 340 replacement cam is a stump puller
at .429/ .444 lift with 204/214 duration @ .050. It is a bit smaller than the stock 340 which
was .429/.444 lift with 210/220 duration.
It will break the tires loose even at low speeds with 21570R14's and 3.23 rear gears. Well tuned
it will kiss 13's @ 100mph, get 20 plus mpg, is nearly impossible to beat steet light to street light
and idles silky smooth.
More than 9 :1 compression is risky but perfect for a low compression 340.
I can hear the Murmurs from the racers!
 
I ran a Mopar Performance 284/484 cam in my 340 and thought it was about right for all around performance. Great on the street with 18 MPG and turned 14.50's at Bandimere (5800 ft, and 8500 ft altitude corrected), so in the mid 13.50's at sea level. Timing is everything with the 340 (and with any engine for that matter). I like 12° initial and 11° distributor advance (22° at the crank) for 34° total. Starts instantly and runs great.
When I restored the Cuda, I put in a different 340 with a Crane 272/280 cam that I got years ago (1990's). This engine is great for the street with good power but excellent manners. I am running 2.94:1 gears so I can cruse at highway speeds in the mountains where 70 is the minimum speed you want to go.
 
RLF...how is the low end torque with that crane cam and 2.94's....and what size rear tires? I have installed 2.94 rear gears in my new project but it will be some time before it's finished. After using 3.23, 3.55 and 3.91's i prefer the 3.23's but i'm thinking the 2.94's may be even better.
 
I can tell that some of you have may have not read my original post I will list a few facts about my car.

Trans- 727
Stall - don’t know I will change if needed
373 or 391 gear
Edelb RPM intake
AVS2 650 can change but I would like to use it.
X heads
TTI headers
MSD 6AL
MSD Distributor
 
Where your willing change stall, carb etc .. Got decent gears it's kind of up to you how wild to go, ir3333 tends to be very conservative with his recommendation others are all out, and most are in the middle somewhere I'd say intake in the 225-235 degree, 108-110, .500 ish lift range. But it's really up to you where the best compromise is.

Unless the cam you got now is killing lots of low end probably ain't gonna change much there. Stall probably give your best gains if looking for more out of the hole power.
 
Where your willing change stall, carb etc .. Got decent gears it's kind of up to you how wild to go, ir3333 tends to be very conservative with his recommendation others are all out, and most are in the middle somewhere I'd say intake in the 225-235 degree, 108-110, .500 ish lift range. But it's really up to you where the best compromise is.

Unless the cam you got now is killing lots of low end probably ain't gonna change much there. Stall probably give your best gains if looking for more out of the hole power.
That’s a good point, thanks
 
I can tell that some of you have may have not read my original post I will list a few facts about my car.
If you get a chance, please let us know how long your pushrods are with those 273 rockers (and whether the cam is hydraulic or solid). Thank you.
 
If you get a chance, please let us know how long your pushrods are with those 273 rockers (and whether the cam is hydraulic or solid). Thank you.
I will when I get to it. Unfortunately my wife recently had major surgery so I won’t be back under the hood for at least another 3-4 weeks.
 
we can recommend cams till the cows come to roost, but without knowing what the compression ratio is roughly, kinda, sorta, or there abouts, all of this is mental masturbation.

you've got gear, and you're willing to up the stall which is like, half the equation of camshaftery.

on the motor you've got good bones with the heads, intake, carb, headers & ignition.

figure out that last piece of the puzzle and then you can get a better handle on what cam(s) you should be looking at. because for all we know it's 9:1 and that ain't gonna fly with 500+ lift and 280 duration.
 
we can recommend cams till the cows come to roost, but without knowing what the compression ratio is roughly, kinda, sorta, or there abouts, all of this is mental masturbation.

you've got gear, and you're willing to up the stall which is like, half the equation of camshaftery.

on the motor you've got good bones with the heads, intake, carb, headers & ignition.

figure out that last piece of the puzzle and then you can get a better handle on what cam(s) you should be looking at. because for all we know it's 9:1 and that ain't gonna fly with 500+ lift and 280 duration.
Like I said earlier I was waiting for delivery on a compression tester and it finally arrived 2 days ago.
 
Like I said earlier I was waiting for delivery on a compression tester and it finally arrived 2 days ago.
well what's the hold up then? i heard ya'll are having a cold snap out there and it's only 100* which is down right tropical!

chop chop amigo!
 
That's what I bolted into my fairly stock 340 build (9.75:1 compression, stock manifolds, Eddy intake and AVS 650 carb, 3.55 4 speed). I've run it on the test stand...not much of a lope but sounds good. I'm sure I could get more out of the engine but that wasn't the point. If I recall correctly its installed 2 degrees advanced.
how do you like the performance of your set up?
are you happy with your cam choice?
your current set up is almost identical to what i will be doing except mine is an automatic
 
well what's the hold up then? i heard ya'll are having a cold snap out there and it's only 100* which is down right tropical!

chop chop amigo!
What he said ^^^^. Now get crackin.
 
how do you like the performance of your set up?
are you happy with your cam choice?
your current set up is almost identical to what i will be doing except mine is an automatic
The car is still under restoration. If I had headers like the OP I would probably go for a more modern hotter cam.
 
I wasn't being conservative. Whenever a cam is discussed everyone automatically thinks quarter mile. In his post he said he is not racing. I was thinking lo compression 340 strictly on the street that will boil the tires and "pull stumps"! from 1000 rpm up.
 
I would run something like what I posted OR the Lunati 268 grind. A touch high on the lift though, they like a dual spring with that one. Maybe get Ken Heard at Oregon to grind a Comp 268 clone.
Why not use the Hughes Hug1110P springs on the Voodoo 268 or the XE274H cams?
 
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I wasn't being conservative. Whenever a cam is discussed everyone automatically thinks quarter mile. In his post he said he is not racing. I was thinking lo compression 340 strictly on the street that will boil the tires and "pull stumps"! from 1000 rpm up.
Worrying about performance at a 1000 rpms sound being very conservative to me, it's not a slight, nothing wrong choosing cams on the conservative side especially if the OP is similar. Yes not everything is quarter mile, but someway it is even if you don't race. If you looking for more power generally your gonna go faster in the quarter mile, so there generally a quarter mile ish performance your looking for be it 15's or 12's or 9's etc... Zero to Sixty or Eighty probably be a better street metric.

To me there's basically three to types of performance on the street part throttle normal driving 1000-2500/3000 rpm and aggressive part - full throttle generally 3000-5500/6500 rpm type performance, Then there's how your car goes between the two.

I think a lot of it comes down how sensitive you are about how your car handles going from normal drive to full throttle performance don't necessarily think its a torque thing, probably how quickly the throttle response is from cam overlap, tune, gearing, stall, velocity etc..
 
Why not use the Hughes Hug1110P springs on the Voodoo 268 or the XE274H cams?
Mainly because for a street car, I've never been hot on really fast rates of lift. Those type of ramps are hard on the valve train.
 
Mainly because for a street car, I've never been hot on really fast rates of lift. Those type of ramps are hard on the valve train.
Ditto. I didn't think the XE cams were really worth it for the street. Some report them to be noisy too. Maybe there is something between the repro '68 4 speed cam and the XE268 for a stockish 340 but I'm not losing sleep over it.
 
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