you should try them both and see which one you like better really. if a motor has enough power a steeper angle will accelerate faster, at least that's how i understand it to work. the good thing is that you have them both and have the luxury of testing to see what works for you as opposed to not knowing before you buy.
Recomend you read this. Lots of info if you actually read it all.
Explaining why could take forever to get you to really understand. Try reading that site. My guess is the 34degree will cause your RPMs to go up a lot and your sled will pull less. for a stock primary id recomend a 40/32 or 42/36 helix. Something close to that should work good with your stock springs and primary. Read that site where it talks about what to record on test runs. Your sled will tell you what it wants.
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