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Discussion Starter #1
Is there any advantage of 1.6 over 1.5,like getting valve off seat faster. u see a lot of your big hp motors running 1.6 to 1.8 and i think clearance is not a issue
 

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Lifts the valve more and adds a small amount of duration ...or at least trick the.motor ..lol
.1.7 1.8 etc the cam lobes were designed for those ratios .
 

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The higher ratio changes acceleration at the valve. It does not change opening and closing at the seat duration. It opens the valve toward peak lift faster once off the seat.
 

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Discussion Starter #6
so what do u guys think? i think i need more lift, maybe little over 700, sbc 427 afr heads. i have shaft rockers so spend money on 1.6 or custom grind cam and hope to clear cam to rod.money is little tight right now . thanks
 

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I consider it one of those fine tuning things. You set the car's combo up with the proper camshaft choice and often you can find power (or loose it) by playing with rocker ratios, cam timing, carb spacers, ect...
 

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I think it would be cheaper and make more sense to have the correct cam made
You cant get as much lift, as quick as you might like, just in a camshaft. :smt102
 

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Discussion Starter #11
thanks for the advise guys,i just worry about getting a really tiny base circle cam but peaple do it everday.i'll have to look at both ways and see what works best for my combo. thank
 

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yeah big base circles are cool , on std. bearing size sbc cams mostly flat tappets i'll go to a 1.7 or 1.8 stud mount so we can back off the lobe action and lobe lift on the intake side and exh. i fool with 1.3 to 1.5 ratio. we have some great fitting offset trunion with longer arm bodys in a stud mount. not too many 1.7 long arm stud mounts out there but we have had them for years , they are the ticket for lift and geometry nothing fits better. been all the way to a 1.85 stud mount on 23 degree bowtie. we even have a 1.6 .150" offset studmount for the tight fitting RHS heads or wide port heads that some air flow gurus come up with . shoot me pm if you need any weird rockers with offsets and backsets and long arms yadda yadda .
 
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