Cam and valvetrain longevity....??? low duration high lift...
#561
Geronimo36
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Before we get too excited, anyone see my post earlier, about the throttle cable issue on the same dyno? That would certainly have an effect on tims dyno number if in fact, thats what was happening, but not in the boat. Throttle controls when using a servo, can fuk up. I like when some shops mount a camera above the throttle plates during a dyno pull, where you can see creep back.
A more common cause for both the low measured air flow and vacuum would be that the carburetor was not mechanically at WOT during the pull. Sometimes it is hard to get good carburetor travel with the available leverage and linkage. Older dyno's with the water piston used to creep all the time and loose the WOT during a test session, even the newer ones with servo or cable linkages can creep or loose the WOT capability.
A more common cause for both the low measured air flow and vacuum would be that the carburetor was not mechanically at WOT during the pull. Sometimes it is hard to get good carburetor travel with the available leverage and linkage. Older dyno's with the water piston used to creep all the time and loose the WOT during a test session, even the newer ones with servo or cable linkages can creep or loose the WOT capability.
didn't he say he was getting really low AFR numbers or something?? If the throttle was open all the way in the boat he's drawing more CFM and the carb is drawing more fuel (rich).
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#564
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I would think it would cause issues in the boat because if it was dyno'd and tuned at part throttle the tune in the boat (WOT) would be off.
didn't he say he was getting really low AFR numbers or something?? If the throttle was open all the way in the boat he's drawing more CFM and the carb is drawing more fuel (rich).
didn't he say he was getting really low AFR numbers or something?? If the throttle was open all the way in the boat he's drawing more CFM and the carb is drawing more fuel (rich).
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#565
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Here you go, just pout a couple gallons of this in the tank next fillup....
https://www.summitracing.com/parts/klz-kl-640/overview/
https://www.summitracing.com/parts/klz-kl-640/overview/
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#566
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Here you go, just pout a couple gallons of this in the tank next fillup....
https://www.summitracing.com/parts/klz-kl-640/overview/
https://www.summitracing.com/parts/klz-kl-640/overview/
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#568
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#570
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