What are the best VH45 heads?
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elwesso
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Re: What are the best VH45 heads? (gs14racer)
Overall, I dont think the intake ports make THAT big of a difference. Technically the later style heads flow SLIGHTLY more but sometimes you can get more velocity through the siamesed.. All depends what you're after, the siamesed might be better for N/A.
I think the earlier heads are more desirable simply because of the sodium filled exhaust valves.
I think the earlier heads are more desirable simply because of the sodium filled exhaust valves.
Re: What are the best VH45 heads? (elwesso)
Yea, i guess im after good power n/a.
Im in the process of getting another motor built and the motor i got coming is a 94, i know the later 94's come with oval port heads but I was just wondering if i made a bad move on the 94 motor.
It will have individual throttle bodies.
Im in the process of getting another motor built and the motor i got coming is a 94, i know the later 94's come with oval port heads but I was just wondering if i made a bad move on the 94 motor.
It will have individual throttle bodies.
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Q45tech
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Re: What are the best VH45 heads? (gs14racer)
With individual TB, selecting the point [length from air horn to closed valve] is critical as to where [what rpm] the wave reinforcement occurs based on after BDC...........cams and length interreact to form the boost in torque over a narrow rpm range.
The oem air duct/plenum/runner design boosted torque at 1550-2000 rpm, 3800-4400, and 5500-6,000 rpm expect to lose 4, 8, 12% peak torque below your new tuned length rpm.
Some of this can be made up from less restriction by muliple throttle plates.
Measure oem TB at WOT it has a maximum of ~~ 8" W.C. [1.7%] use a manometer across TB to measure restriction.
Be sure to taper the runner [4-6 degrees] from horn to head to braoden the rpm where the reflect occurs and to strengthen the ram effect.
The oem air duct/plenum/runner design boosted torque at 1550-2000 rpm, 3800-4400, and 5500-6,000 rpm expect to lose 4, 8, 12% peak torque below your new tuned length rpm.
Some of this can be made up from less restriction by muliple throttle plates.
Measure oem TB at WOT it has a maximum of ~~ 8" W.C. [1.7%] use a manometer across TB to measure restriction.
Be sure to taper the runner [4-6 degrees] from horn to head to braoden the rpm where the reflect occurs and to strengthen the ram effect.
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Guishnu
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Re: What are the best VH45 heads? (Q45tech)
I really REALLY wish i understood what you were on about some times. Im sure it's bloody interesting.
Q45tech wrote:With individual TB, selecting the point [length from air horn to closed valve] is critical as to where [what rpm] the wave reinforcement occurs based on after BDC...........cams and length interreact to form the boost in torque over a narrow rpm range.
The oem air duct/plenum/runner design boosted torque at 1550-2000 rpm, 3800-4400, and 5500-6,000 rpm expect to lose 4, 8, 12% peak torque below your new tuned length rpm.
Some of this can be made up from less restriction by muliple throttle plates.
Measure oem TB at WOT it has a maximum of ~~ 8" W.C. [1.7%] use a manometer across TB to measure restriction.
Be sure to taper the runner [4-6 degrees] from horn to head to braoden the rpm where the reflect occurs and to strengthen the ram effect.