340 cam in a 318

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I put a .474/280 MP cam in a stock 318. That is for sure larger than a 340 cam. I put a TQ on top. It was faster. I won races. Even with my stock TC and 2.76 gears.
How did it idle? How slow could you get it to idle and how did that work with a stock converter?
 
That's awesome. What cylinder heads, intake manifold and carburetor are you running with the 340 cam.

Heads are same as the truck J Heads, casting #596, 1.88 /1.60 valves.

Either stock truck 360 4bbl intake or the Weiand 8022 aluminum intake. Or the stock 340 70s era non smog cast iron intake.

1406 and1405 Edelbrock carbs used, mostly 1406 electric choke street carburetors work well.

This is a 360 here.

Usually like to do the LD4B intakes on the 318s if you can find them. Better port matching to the 318 heads.

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Wouldn't the compression ratio be to low to support that cam
Please read what I wrote. It was faster. Shall we break down all the numbers on why it shouldn't be faster? And why it would be slower?? The bumble bee cannot fly because it's wings are to small for it's body. Except, when the bee is let go it flies. Savy?
 
How did it idle? How slow could you get it to idle and how did that work with a stock converter?
I would guess 600 in gear. No issues with the converter.

  1. Now we can make the same list with EVERY engine:
  2. Would of it been faster with a 3k stall and 3.91's? YES
  3. Would of it been faster with 9.5 compression ???? YES
  4. Would of it been faster with a 4" stroker kit ????? YES
  5. But was it faster than the stock 318 cam >>>???? YYYYEEEEEESSSSSSSSSSS !!!!! :D
 
My suggestion is this to Dan: Dan, if you are leaving it a 2bbl, stock everything and never plan to go above 4k rpm's, then leave the stock 318 cam in there. But if you are going to add a 4bbl and dual exhaust (or headers), and you will occasionally will play around to 5500 rpm's, then the 340 cam will be your friend.

Somehow I feel like I've said this before... lol
 
I would guess 600 in gear. No issues with the converter.

  1. Now we can make the same list with EVERY engine:
  2. Would of it been faster with a 3k stall and 3.91's? YES
  3. Would of it been faster with 9.5 compression ???? YES
  4. Would of it been faster with a 4" stroker kit ????? YES
  5. But was it faster than the stock 318 cam >>>???? YYYYEEEEEESSSSSSSSSSS !!!!! :D
That's good to know. Most every discussion about using a 340 cam (or a bigger one) is that it's soft on the bottom end and it idles roughat idle and you have a issue with a stock converter with too low of a stall. No reason to rip the u joints out every time you shift out of park into gear.
 
From this photo, there's no way of telling if it's a 318 or a 360.

If you look closely at the 318 intake gaskets you will see the head ports are larger than the intake gaskets, large port 360 heads.

Was doing a mock up at the time as to which intake manifold to use. Was fitting an LD4B for a 318 on the 360 as I have 3 of them and wanted to see if it would flow right at the head. As a mock up, that is where the engine sits for now until I get back from the Winter get away. Then will get things finalized when I get back.
 
That's good to know. Most every discussion about using a 340 cam (or a bigger one) is that it's soft on the bottom end and it idles roughat idle and you have a issue with a stock converter with too low of a stall. No reason to rip the u joints out every time you shift out of park into gear.
It was a little soft on the zero to 20 mph, but not dead. I could still get rubber from my P245/60R14's on a smooth road. It didn't spin on chip seal. However, once it hit about 35 mph with the 2.76's and stock converter, it would outpull any 318 2bbl cam.
 
My suggestion is this to Dan: Dan, if you are leaving it a 2bbl, stock everything and never plan to go above 4k rpm's, then leave the stock 318 cam in there. But if you are going to add a 4bbl and dual exhaust (or headers), and you will occasionally will play around to 5500 rpm's, then the 340 cam will be your friend.

Somehow I feel like I've said this before... lol
I said it in my post above here somewhere I believe. Way too many guys just want to stuff a cam in with nothing to make it work. With a stock Teen, you should always do a distributor curve, dual exhaust (even if you keep the stock manifolds), and a 4 barrel and intake.
 
I said it in my post above here somewhere I believe. Way too many guys just want to stuff a cam in with nothing to make it work. With a stock Teen, you should always do a distributor curve, dual exhaust (even if you keep the stock manifolds), and a 4 barrel and intake.
I wouldn't put headers on without a cam and maybe some good heads (for flow and better compression)
 
I said it in my post above here somewhere I believe. Way too many guys just want to stuff a cam in with nothing to make it work. With a stock Teen, you should always do a distributor curve, dual exhaust (even if you keep the stock manifolds), and a 4 barrel and intake.
The tune is huge! And what I posted above is not ideal, but it was an improvement. I wouldn't recommend that .474/280 cam in a combo as I had, because there are better choices for sure and get greater improvements. Keep in mind these were A-bodies, and I have not done anything like that in a Maxi van... LOL.
 
75 318 69 340 cam 360 heads 69 340 intake n exhaust 340 avs carb = one fun 64 barracuda 4spd with 2.76 in the butt it got 21mpg om the road . we drove it n drove it everyday . oh ya 52 241 hemi dual point dizzy ign .
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All I was wanting to know was about people's personal experiences with a 340 cam in a 318, did they notice a performance gain,what other modifications did they do if any when they went with the 340 cam? I know that the 340 cam isn't available anymore so what would be pretty close to it? I've been reading up on the Howard's cam 255* / 261* and it has been recommended by a couple of guys. Is a lunati or a comp xe grind of similar specs worth looking into? Opinions are good, but I'm looking for guys who have had personal experiences with any of these cams.

My friend Brian has the mopar performance 340 cam in his 1969 318 stock 9.2:1 compression engine stock bore and stock valve relief pistons. Also has the mopar closed chamber 302 heads and the thin .028 ths head gaskets with an LD4B intake and a 1406 carb 3:23 rear gears in his '72 Duster.

Also has TTI 2.5 X-PIPE dual exhaust on stock A body cast iron manifolds.

Yes it performs, cr is right at 9.5:1

We just laugh and look at each other when he puts his foot into it. Unreal!

It's pretty much you need to drive with both hands.

72 Duster 318.jpg
 
My friend Brian has the mopar performance 340 cam in his 1969 318 stock 9.2:1 compression engine stock bore and stock valve relief pistons. Also has the mopar closed chamber 302 heads and the thin .028 ths head gaskets with an LD4B intake and a 1406 carb 3:23 rear gears in his '72 Duster.

Also has TTI 2.5 X-PIPE dual exhaust on stock A body cast iron manifolds.

Yes it performs, cr is right at 9.5:1

We just laugh and look at each other when he puts his foot into it. Unreal!

It's pretty much you need to drive with both hands.

View attachment 1715911198
I don't have the cam but I have 340 manifolds, LD4B, 650 AVS2, and I need new exhaust. All yet to install. I do have a 3.23 SG in the car.
 
By the way for those that want to know, the mopar performance 340 cam is no longer available. Have been using the Melling SPD-22 as a good replacement to the 340 cam.

Just about identical grind numbers. About 10 more on the duration that's it. And is still available online, Summit and ebay, maybe Jegs too.
 
By the way for those that want to know, the mopar performance 340 cam is no longer available. Have been using the Melling SPD-22 as a good replacement to the 340 cam.

Just about identical grind numbers. About 10 more on the duration that's it. And is still available online, Summit and ebay, maybe Jegs too.
Check out Sealed Power LS644 and Elgin has one as well (I don't have the number) but 216/216 @ .050 272/272 .454/.454 110°
 
Now for those that are doing comparisons with people with real hands on experience.

Here is a 1969 Satellite Stock 9.2:1 compression 318 engine with factory open chamber heads, was a 2 barrel factory car with 727 trans and 2.94 rear gears.

Anyhow swapped on the 1406 Edelbrock 600 cfm carb with the 2 to 4 barrel adapter, so did not have to change the intake and it was still port matched to the 318 heads.

Really woke up the car by giving it more fuel, the stock 2 barrel is an economy carb and they leak gas bad so it had to come off.

The big thing that in '69 they had great compression out of the factory, and just by adding a large volume of fuel and air it added a lot of performance and with the added plus of the secondaries on the four barrel, it was a joy to drive.

Glad I did not have to tear open the 37,000 mile original engine, original car to do the 4 bbl upgrade. Still wanted to keep it as close to original as possible, it was such a cherry.

 
Now for those that are doing comparisons with people with real hands on experience.

Here is a 1969 Stock 9.2:1 compression engine with factory open chamber heads, was a 2 barrel factory car with 727 trans and 2.94 rear gears.

Anyhow swapped on the 1406 Edelbrock 600 cfm carb with the 2 to 4 barrel adapter, so did not have to change the intake and it was still port matched to the 318 heads.

Really woke up the car by giving it more fuel, the stock 2 barrel is an economy carb and they leak gas bad so it had to come off.

The big thing that in '69 they had great compression out of the factory, and just by adding a large volume of fuel and air it added a lot of performance and with the added plus of the secondaries on the four barrel, it was a joy to drive.

Glad I did not have to tear open the 37,000 mile original engine, original car to do the 4 bbl upgrade. Still wanted to keep it as close to original as possible, it was such a cherry.


I love '68 to 70 satellites
 
I consider a 340 cam mellow for anything I'd build.
Heck if that's all I had I'd slam it in a 273.
Whoever says a 340 cam is too big for anything should really stick to stock.
 
I consider a 340 cam mellow for anything I'd build.
Heck if that's all I had I'd slam it in a 273.
Whoever says a 340 cam is too big for anything should really stick to stock.
ka ka ka ka ka ka BOOM !!!!! nailed it!
 
I've done the 360 cam (252/.420"?) in a 318-2bbl with fantastic results, also had headers. I think the stock 318 grind is like 248/.390" so it was a noticeable improvement, using all the stock 318 springs, etc. I would recommend 340 red valvesprings and a compression increase via KB or SRP/ICON/ProTru flat tops and using 360 heads for maximum benefit with a 4bbl and that 340 factory cam. I have long wanted to do a 318 that way, 340 cam with iron exhaust manifolds or shorty headers and a 340 intake with a spreadbore carb (TQ or Holley).
 
Heads, cam, - no one has mentioned ignition.
- if you recurve w about 15* initial, you will see significant improvement down low and will idle like a happy cat.
 
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