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439 Views 1 Reply 2 Participants Last post by  Tom White
What kind of performance has people gotten on a stock 99mxzx440 between the stock helix, and lets say a 48-44 helix.. I would be going from a beige spring, to GP's Blue Spring, any thoughts? I just ditch bang, so top end isnt super important, 60-70 is just fine with me
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Just wrote a lengthy reply and somehow the website must have eaten it. Can't remember exactly what I wrote, but it went something like this:

You have two choices. One, experiment on your own or two, buy Dynamoe Joe's kit. If you go it alone, I would suggest starting with a 50/44 or 52/44 and the blue spring. You may also find your sled can pull a 54/44 or even 56/44, but it will need to be a "short" helix. Short meaning the 54 or 56 degree section is, well, short so the motor only sees the extra loading for a short time and then gets back to the 44 degree section. Speedwerx used to make shorties and I played with them, but found myself enjoying the sled more with a good old 50/44 in there and adjusting spring tension as conditions allowed.

Not to sound like a Dynamoe Joe groupy, but you should strongly consider getting his kit. Joe has custom cut the helix angles to match the power output of your exact sled. He has also matched springs for you so you can capitalize on the machines narrow power band even after the engine gets hot and most sleds start bogging with stock or over aggressive helixes or soft springs.

The choice is yours. Good luck.
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