Yea in the beginning when i ordered the epi red 205/310, like you i believed it would be the same as the Dalton 205/310.
I quickly found out there not even close. This is due to how epi measure their springs. So with talking to epi i was told when they measure there red spring at the Doo spec it would actually be a 250 start vs 205.
I also tested the Dalton 205/310 it was ok but not what i was looking for. Only a small difference from the oem G/G.
" Do you think it needs the doo 231/303 if even needed with the primary spring change? "
I can't say because what i like you may not.
I do agree with the stock helix vs the 44/40, i hated it and could not get it out fast enough.
So many ways to skin the cat here. I first started in the primary with the 170/350 and the oem G/G & the Dalton red, this helped my rpm but when getting off the gas and quickly back into it i found it still a little slow to recover.
Put that epi red in and wow it was instantaneous with zero delay and very, very hard pull.
Here's the but. Unfortunately i was not getting full shift out of my secondary with the red epi. I found the spring was too long and coil binding.
Also it in combination with the primary 170/350 i was now over revving.(that was a first ever)
I really like that spring and would still be running it if not for coil binding.
The closest spring i can find of any kind to the epi red 205(250) by doo spec would be the doo purple/purple 231.
Sooo this is what i switched to late last season. I also went back to the oem primary 170/300 because the 170/350 would over rev at times on cold days with the P/P.
Remember this is on my 900R XRS not a Mach, those arms change everything.
If you zoom in you can see how the red epi was coil binding.
It's between the Dalton red and P/P.
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