General Category > Quadrajet Carb Talk and Tips

Stump puller or Old Faithful?

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Cliff Ruggles:
Those cams are pretty small for HR's.

I tried one smaller 230/236/112 HR once, it did OK (will attempt to attach the dyno sheet), but not nearly as well anyplace as the larger custom grinds we typically use with .361" or .380" lobes.

For that reason if you are sticking with smaller lobes and a lot less valve lift/movement I'd go with the larger 236/242 cam on a 114LSA......Cliff

Stripes:
Thank you for your input.

The plan intially was to go with the Stump Puller,  230/236 dur @ .050" lift .590"/.592" lift with 1.52 ratio rockers 112 lobe sep. However, the Edelbrock D port heads only allow .575" lift before bind in the out of the box  configuration from them. Butler and SD are both 8-10 weeks out to sell any heads with a port job or improved valve height, so I fell stuck with the lower lift comp cams. i dont have 2 months to wait for parts.

Cliff Ruggles:
Nothing at all wrong with the smaller lobes, but keep in mind they are smaller cams even though they will share the same .050" specs on paper. 

The larger lobes will have more effective duration everyplace, so act quite a bit bigger.  If you are trying to keep up with them for power it's going to take a few more degrees duration.  Since they don't make (at least as far as I know) bleed down HR lifters idle quality will suffer just a tad with the longer seat timing cam.

If you want to mimic the power of the Stump Puller choose lobes with another 5-6 degrees @ .050" and at least as much at .006".  Keep the lift well under what the springs can handle, or down around .520-540".  Pushing it out on a 114LSA will help just make sure to put the ICL at 109-110 degrees so it's not "lazy" at low RPM's........Cliff

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