Stroker 383... vibration with stock damper
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From: Orange Kounty, Kalifornia
Stroker 383... vibration with stock damper
I have a vibration from 3000 - 6000 RPM. M6 Z28 1995.
It doesn't matter if the engine is revved in neutral or driving down the road.
Someone was saying once that the 3.75 stroke crank is based off the 400 cu in engine and needs a different balancer. The rotating assembly is forged and internally balanced. Do I need a new balancer too?
It doesn't matter if the engine is revved in neutral or driving down the road.
Someone was saying once that the 3.75 stroke crank is based off the 400 cu in engine and needs a different balancer. The rotating assembly is forged and internally balanced. Do I need a new balancer too?
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From: Bay Area, CA
If the motor is internally balanced I assume you used a neutral balance flexplate or flywheel right? The stock unit is externally balanced.
The 400 chev, 383 variants, and once piece rear main 350's are internally balanced on the front half, and external on the rear unless setup differently by your machine shop or parts manufacturer. (Damper is the same)
The 400 chev, 383 variants, and once piece rear main 350's are internally balanced on the front half, and external on the rear unless setup differently by your machine shop or parts manufacturer. (Damper is the same)
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Yes, the flywheel is neutral balanced (aftermarket lightened flywheel).
The clutch is a centerforce DFX. It says to mark the yellow spot to the mark on the flywheel... none since it is neutral balanced.
My hunch is that it is either the harmonic balancer off the crank or that the clutch is off balance though centerforce says it is neutral balanced.
The clutch is a centerforce DFX. It says to mark the yellow spot to the mark on the flywheel... none since it is neutral balanced.
My hunch is that it is either the harmonic balancer off the crank or that the clutch is off balance though centerforce says it is neutral balanced.
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Machinist One - So if I understand you correctly, the damper (stock LT1) is neutral balanced up front but the flywheel is not at the rear.
My hunch is that the factory balancer was set up the weights of a stock 350 LT1. Adding the 383 has different weights and harmonics, as well as a different piston to rod ratio. So, would the stock balancer affect the vibration? Should I get an aftermarket Fluidampr to handle the vibrations? Or is that a waste of money?
About the rear, the flywheel and clutch are Centerforce. They say they are neutral balanced but that could also be a source of the vibration. But, I really don't want to have to separate the M/T from the block again to pull the clutch and flywheel. It is another possibility, but Centerforce says they are neutral balanced.
First - balancer... easy change out if necessary
Second - flywheel / clutch removal and re-balance... PITA!
My hunch is that the factory balancer was set up the weights of a stock 350 LT1. Adding the 383 has different weights and harmonics, as well as a different piston to rod ratio. So, would the stock balancer affect the vibration? Should I get an aftermarket Fluidampr to handle the vibrations? Or is that a waste of money?
About the rear, the flywheel and clutch are Centerforce. They say they are neutral balanced but that could also be a source of the vibration. But, I really don't want to have to separate the M/T from the block again to pull the clutch and flywheel. It is another possibility, but Centerforce says they are neutral balanced.
First - balancer... easy change out if necessary
Second - flywheel / clutch removal and re-balance... PITA!
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