George recommends this custom cam grind he calls the Cobra Jet profile. Has anyone used this?
How did it perform? What kind of street manners does it have?
I'm wondering if this would be a good street cam for a quad weber 48 idea setup with its low overlap.
If no one has put this cam in their engine, has anyone perhaps done a desktop dyno run of it?
George, perhaps you could share some thoughts on what the expected performance would be with this cam profile.
Thanks,
Jake
Camshaft Spec:
Grinder: Bullet Racing Cams of Olive Branch, Mississippi
Telephone (662) 893-5670
Engine: Ford 351 Cleveland, 4V cylinder heads
Hydraulic flat tappet camshaft
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Intake Lobe: #HF275/328 (CRA, designed for Ford 0.875 tappets)
Intake lobe mathematic centerline = 112° ATDC
Exhaust Lobe: #H287/3283 (CRA)
Exhaust lobe mathematic centerline = 116° BTDC
114° lobe separation angle (camshaft degrees)
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Exhaust valve opening = 79.5° BBDC
Intake valve opening = 25.5° BTDC
53° overlap
Exhaust valve closing = 27.5° ATDC
Intake valve closing = 69.5° ABDC
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275° advertised intake lobe duration
223° intake lobe duration at 0.050"
Intake lobe hydraulic intensity = 52
0.567" theoretical intake valve lift (1.73 rocker ratio)
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287° advertised exhaust lobe duration
235° exhaust lobe duration at 0.050"
Exhaust lobe hydraulic intensity = 52
0.568" theoretical exhaust valve lift (1.73 rocker ratio)
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Request to have the custom ground flat tappet cam nitrided (surface hardened) and polished for the best possible durability. I believe the hydraulic intensity of the flat tappet camshaft lobes I’ve selected plus the desire for a long wearing and trouble free valve train warrants this additional expense. Buy a set of Johnson HT900 hydraulic lifters from Bullet Racing Cams too.
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