Cam Help

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Jolt63

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Sorry if I'm putting this in the wrong place, but I'm new here and still finding my way around.

So this past summer I bought my first mopar. It's a 1969 Plymouth Sport Fury 383/727. The guy I bought the car from bought it as a pair with another car that he wanted. Both had sat in a field for apparently as long as ten years, and little is known about their history. Although, this thing has evidence of bracket racing all over (kill switch under the hood, hood pins, cutouts, extended wheel studs, hooker super comp headers).

Long story short, the motor seemed to run good when I bought it but started smoking like a son of a ***** and making noises, so it's getting a rebuild.

My question is really about cam selection. Just like any hotrodder with a mild ego issue, I want that good lopey idle, but the last thing I want is to overcam the car, which I hear is easy to do with a 383. The motor will have about 9.5:1 with a Holley 700cfm and Weiand intake. I don't think the converter is stock, and wouldn't be surprised if it's 2k+ stall. I know this is a big car, and I'm not expecting a rocket ship, but I do want that good idle while still keeping it pretty streetable. After lots of research, I'm thinking about the Comp 275DEH. Here are the specs:
Adv duration: 275/284
Duration @.050: 219/235
Valve lift: .462/.482
LSA: 110
My question is, can I run this cam with just a spring upgrade in the stock 906 head? I think I remember somewhere that comp has a good single spring for this cam. Also, from my research it seems like the .462/.482 might be pushing the amount of lift these heads can handle. Would that be ok?

I'm definitely open to other cam suggestions if you can convince me that it will do what I want better than the 275DEH.

Thanks,
Jolt
 
Good choice on cam . Why not have the machine shop check the springs you have to see if they will work?
 
That cam would prob work. If your out for a cam that sounds lopey with some good performance gains as well look into the comp thumpr cams.
 
No matter what cam you choose make sure to buy adjustable rockers. Bigger cams don't have taller lobes. They have a smaller base circle. which makes the higher lift. You will need to adjust for proper preload or Zero lash and a quarter turn down is what I use.
 
If it really is about the sound, take a look at the Comp Thumper or the Hughes Whiplash cams.. Decent performance upgrade with the nostalgia sound.
 
I didn't see the head casting# in the OP.

I had to machine the spring landings (guide boss?) on my 906 heads for a DC 284/484 cam and the recommended spring .

Not a big deal.

My motor was a stock HP 1970 383 with advertised 9.5:1 compression.

Your cam should be fine in a motor with the same or less comp.
 
Have the machine shop check spring pressure at installed height for what you have now.If they come in at 100 to 120 lbs.seat pressure or can be shimmed without coil bind to get to .500+.080 lift you can use yours or just get mopar perf. drop in ones. you dont necessarily need comps brand.
 
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