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stugray |
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Advanced Member ![]() ![]() ![]() ![]() Group: Members Posts: 3,825 Joined: 17-September 09 From: Longmont, CO Member No.: 10,819 Region Association: None ![]() |
I am adjusting the valve geometry while putting in a Raby 9700 cam and I am seeing .38 on the exhaust cam lift and .496 at the valve (an exh rocker ratio of 1.3) and I have a .39 on the intake with a .546 at the valve ( an int rocker ratio of 1.4) is this what everyone else gets for rocker ratios:
Intake rocker ratio = 1.4 Exhaust rocker ratio = 1.3 These are the 1.7 (1.8?) rockers that accept the 911 swivel feet. I am using the swivel feet, have modified the rocker faces, adjustable push rod, and zero lash to do the meaurements. Do those rocker ratios look like stock? I want to take 50 thousandths off the Combustion chambers to increase the CR, but my measurements say I wont have enough clearance on the Intake valve once I shave off 50 thousandths. I only have ~0.075 clearance now from the piston to the Int valve as it is with a deck of 0.030 and everything else (crank & rods) stock - flat top 96mm pistons. That Intake valve travel of ~0.55 looks huge to me. Anyone else care to comment? Stu |
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stugray |
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Advanced Member ![]() ![]() ![]() ![]() Group: Members Posts: 3,825 Joined: 17-September 09 From: Longmont, CO Member No.: 10,819 Region Association: None ![]() |
Jake, the above quote was merely an exact comment (yes, I admit from a competitor).
Here is another quote: "Order a new set from Jake. If he sells them, they are the right ones." http://www.914world.com/bbs2/index.php?sho...=205835&hl= I have also referred numerous people to your website for other items that are not easy to find elsewhere. I have also used every single part in your cam package with the exception of the cam itself (and lifters, I kept them as a set with the cam). I have said from the beginning (even in my tirade) that "The parts that I received from you all appear to be top quality and exactly what I wanted. No complaints from that side of the transaction." The issue here with this cam was because I tried to purchase the cam right in the middle of your whole cam policy change. I was told to just pick one and make the purchase and then we would have our consultation and then you would send me the cam I needed. I received a cam within ~4 days of making the purchase when I had not yet made the appointment for the consultation! (I had assumed that you would hold the order until after). Then I sat on the parts for over a year until my "tirade" about the P&C set. At that point I gave up on the paid for consultation. It was clearly my fault for putting a cam that was not what I needed in my engine the first time around. My assumption that I could survive with an intake lift of 0.368*1.3 = .478 would have been OK. When I found what I REALLY had it was a no-go. As posted above (see top of page 2), the cam card showed "Valve lift = .368" which did not raise a flag until I measured greater than .500 Stu |
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Lo-Fi Version | Time is now: 16th September 2025 - 01:34 AM |
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