360 Magnum vs 340 mild street build - my experience

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Are you happy with your choice of cam? I just bought a 360 magnum long block and want to drop it in my Duster at some point. (Once I am done messing with the 318!) Just trying to decide on a cam.

Cley
which engine? The Duster or the Magnum in the truck ?
 
I could be wrong but i don't think the 360 would out perform the stock 340 4 speed with 14 inch tires street light to street light? Many big inch big HP cars found that out the hard way.
Quite often the big inchers would pass the 340 at the big end...but the quarter mile is not street performance.
To me, most of us have always had a "1/4 mile" marked off someplace out of town where we'd run our cars. To me, that was street racing. As far as stop light to stop light, it's usually all about reaction and traction. But equally geared, both getting traction, I say the 360 for the win. There are two places I found 360's shine against "equally built" 340's. One is the 60 ft (150 ft really...). The other is the big end. Why? The extra torque gets the weight moving (enertia), and at the big end the extra cubes push against the wind pressure in a high(er) gear better.
 
which engine? The Duster or the Magnum in the truck ?
This is a different 360 magnum I bought for the Duster. The truck has a stock 360 Magnum with a carb. I want to upgrade this new 360 Magnum with a new cam and Aluminum heads on the stock short block. I want as much cam as I can get and still retain my vacuum for power brakes and AC controls.

Cley
 
This is a different 360 magnum I bought for the Duster. The truck has a stock 360 Magnum with a carb. I want to upgrade this new 360 Magnum with a new cam and Aluminum heads on the stock short block. I want as much cam as I can get and still retain my vacuum for power brakes and AC controls.

Cley
LOL ... Ha! I meant which cam of MINE are you asking about? The one in the LA 360 in my Duster? Or the one in the magnum in the truck?
 
I was thinking the one in your truck. I will be going roller or sure.

Cley
I like the cam a lot. Idles pretty smooth considering, and pulls hard from the git go to about 5600 rpms - easily can shift at 6k but it doesn't gain anything.
 
Are you happy with your choice of cam? I just bought a 360 magnum long block and want to drop it in my Duster at some point. (Once I am done messing with the 318!) Just trying to decide on a cam.

Cley

stock build or close to it?
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Are you willing to share cam specs? If it's a secret I understand!

Cley
C'mon, man! I have no secrets! :D I share and show everything we do! I posted the cam card here and in the video when we put the Bombcycle together. I'll see if I can find it. That engine would put your Duster deep into the 12's ....
 
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I got that number from the Richard Holdner video. I am looking for the most roller cam I can use and still retain vacuum for brakes & AC controls. I thought maybe a bit more than this cam might be possible.

Cley
Well it’s going to depend on your heads, And how much converter you put in it and what gear is in the back. Will your compression stay around the stock 9:1? Saying I want the biggest cam I can fit usually ends up with the customer saying “the car is a dog until 4000rpm” and the builder says “that’s what you asked for”.
 
It's a stock long block. The car is a 74 Duster with an A500 auto with a stock high stall converter (2500 rpm or so) and a 4.10 gear.

Cley
 
I just watched them all again. You mentioned in one of your video that you used 1.5 rockers. Is this a mistake or did I hear you wrong?

Cley
The cam was ground for a 1.5 rocker. The magnum has 1.6, so that will add about .030 lift.
 
Magnums are the **** period. 5.2 or 5.9 we had a stock 5.2 with 1 dead cylinder and one cylinder with 25 psi run a 9.3-9.5 in the eighth of a mile lol would do great burn outs with 3.55s and a833. i can only image what it will do when we rebuild it with a better camshaft!
 
It would be better if members focused on what there build is and what they did to it as well as the rest of the car.
 
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