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looking for right combination

Huskie007

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I have a cam with a .308 advertised duration, 3500 stall converter and 3.55 rear end... I was wondering if this is the best combo for my 383? Is stall too much?
 
Depends on the weight of the car, gear ratio, head work, intake, compression ratio...is this for your 70 road runner?
 
Depends on the weight of the car, gear ratio, head work, intake, compression ratio...is this for your 70 road runner?

X2! In stock fashion, that is a ton of duration, a lot of stall and not a whole lotta gear. Generally speaking, seems more suited for 4.10's or higher #'s, but like Photon mentioned, there's a lot more info needed.
 
it is a 70 Road Runner.

I have the Edelbrock Power package on my 383 with 727 trans/shift kit. I have not switched gears to 3.55 yet, but decided to keep my current 3.23 gears so I can drive on the freeway a little easier. I am going to go down to the B&M Hole Shot 2400 stall converter hoping to get a little more quickness of the line. I am not a drag racer, but with my current 3.23 gears and the 3500 stall, I am very slow off the line. I hope the stall is not too low for my .308 adv. duration cam and my car will idle at a stop without having to turn my idle to high.
 
Just to give you a comparison.... Currently I have a 512 Stroker. Big inch strokers eat up a lot of gear, a lot of stall, and a lot of duration. Car has 3.91's, 3500 stall, a 289/292 cam (248/[email protected]) and is 632HP/696TQ. That being said, the car would probably like 4.10's a bit better. At dyno, the torque peak RPM was around 4000, and HP Peak around 5400. Car has a choppy idle (idles around 950RPM)

In your scenario, you have a motor that isn't going to eat up all that duration very well. It's going to struggle in the lower RPM's and the 3.23's will make it even worse. Being you have an auto, you can't substitute RPM with your feet. But on the flip-side, if you had a stick you'd be having a 40lb flywheel drag down your RPM'S when hitting the pedal anyways. Bottom line, is with your package you'd want a cam with the max HP/TQ hitting in the lower RPM's. You're not a drag racer, but a 308 cam would be much more suited for someone that is using their max HP/TQ a lot higher up in RPM, like at the drag strip. Basically, If all your power is sitting in the high RPM's, it's not going to be a lot of fun driving it on the street, because your low end and throttle response is going to really suffer. You'd be pretty surprised how just going to 3.55's will improve your get up.
 
Seems to me the 3500 converter helps quite a bit with the fairly long duration cam (nice to know what the .050 number is), fairly tall 3.55 gear & fairly short stroke, low torque motor. The right converter (torque multiplier) can work magic.
 
Stall to low, not enough gear, compression to low, to much duration, not enough cubes. You can mix and match here but what you will have is a street mutt.
Doug
 
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