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Discussion Starter #1
I have a couple questions for you guys running a 200 shot or bigger.

Does anyone have cylinder pressure data showing cylinder pressure spike when a hit comes on ?? This is a valve train related question reguarding opening the exhaust valve.

Is their anyone recording there N/A cylinder pressure numbers and there total cylinder pressure with the nitrous hit ?? And secondly has anyone tested valvetrain deflection as the cylinder pressure rises (obviously on the exhuast side)??

Thanks....
 

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Discussion Starter #2
So no one has an idea what there cylinder pressures are at....at maximum hp ??

Thanks....
 

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Takes sone pretty damn sophisticated equipment ( read expensive) to put a pressure transducer in the cylinder of a running motor.
 

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So no one has an idea what there cylinder pressures are at....at maximum hp ??

Thanks....
Why you focused on exhaust? Nitrous just allows the burning of more fuel it's not forced induction like boost
 

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Discussion Starter #5
Just trying to get an idea about valve train loads. When the exhaust valve is begining to open it is fighting the residual cylinder pressure of a big hit.

I was talking to Smith Bros. and Manton and they were recomending me step to a 3/8ths pushrod for that very reson.

Thanks....
 

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Just trying to get an idea about valve train loads. When the exhaust valve is begining to open it is fighting the residual cylinder pressure of a big hit.

I was talking to Smith Bros. and Manton and they were recomending me step to a 3/8ths pushrod for that very reson.

Thanks....
Years ago when I ran a nitro bike (HD). It was a N/A with Kinsler injection. I was having a issue with exhaust pusr rods getting kicked out of the motor. We ran with open push rods (no covers) and no oil to top end. We ran a Smith Brothers 3/8 push rod and couldn't find anything causing the issue in any other part of the valve train. We began thinking exactly what you are talking about, cylinder pressure. I stepped up to a 7/16 pusgrod on the exhaust and never had another issue. What was happening was the exhaust push rod was deflecting in attempt to open the valve against the cylinder pressure and simply kicking it out of the motor.
I know this is a totally different motor, combination and application, but your thoughts do have merit.
 

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Discussion Starter #7
Thanks guys....are most of you guys who spray more than 200...running 3/8ths or larger pushrods ??

Thanks....
 
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