Paul
Nitro Member
A quick and cost effective way to limit the nitro speeds and get back to 1/4 mile racing could be the following:
I think Dale Armstrong's original suggestion to reduce power by having a max 6 to 1 compression ratio made sense, and the initial testing that was done on it apparently looked good.
Why not enforce a max 6 to 1 compression ratio while also requiring that the engines be de-stroked from their current stokes to accomplish the reduction?
The only change required would be new cranks, all the current pistons, rods and cylinder head gaskets would be retained.
Making a quick estimate shows that reducing the current crank stroke from 4.5" down to 4.43" would knock about half a compression point off, or down from the typical 6.5 ratio to the required 6.0 ratio. This also knocks the displacement down from 500 to 487 cu in, not huge but it will knock the speeds down a little more than a compression ratio change alone.
So the rule would be max compression ratio of 6 to 1, max stroke of 4.43" and max displacement of 487 cu. in. The advantages are only a crank change is required, all the current pistons, rods and head gaskets are still useable.
Paul T.
I think Dale Armstrong's original suggestion to reduce power by having a max 6 to 1 compression ratio made sense, and the initial testing that was done on it apparently looked good.
Why not enforce a max 6 to 1 compression ratio while also requiring that the engines be de-stroked from their current stokes to accomplish the reduction?
The only change required would be new cranks, all the current pistons, rods and cylinder head gaskets would be retained.
Making a quick estimate shows that reducing the current crank stroke from 4.5" down to 4.43" would knock about half a compression point off, or down from the typical 6.5 ratio to the required 6.0 ratio. This also knocks the displacement down from 500 to 487 cu in, not huge but it will knock the speeds down a little more than a compression ratio change alone.
So the rule would be max compression ratio of 6 to 1, max stroke of 4.43" and max displacement of 487 cu. in. The advantages are only a crank change is required, all the current pistons, rods and head gaskets are still useable.
Paul T.