Standard Spec YPVS 350 Barrels

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two-stroke-brit
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Re: Standard Spec YPVS 350 Barrels

#16 Post by two-stroke-brit » Tue Oct 03, 2017 2:12 pm

evan_calgary wrote:The transfers are the limiting factor on these barrels for flow. Thus why many of the aftermarket barrels can get substantially more power. Optimal transfer sizing. When you start messing with the size of the port windows you will majorly change power characteristics though.

I am on Rory's team when it comes to tuning. Bigger carbs are of no value on a stock motor. Throw on some pods and call it a day. Zeel may be worth some power but I didn't really see it. Of course if you have piles of tuning and dyno time then sure there are gains to be had. Stock carbs can even work on 396 granted they may cut a bit of top end.
"muttsnuts" on the rdlccrazy site did a dyno day last year and documented each upgrade and and increase it gave .
zeel gave approx a 5bhp gain on its own (with better curve ,not sure if he fitted a 4 degree key as well).

Just FYI.
Mark
350LC,Athena 392 big bore,stock porting,swiss cheese air box,stock reeds,spec11 pipes.(now TSA big bore pipes)
She might not be pretty but she will always be a fun ride


1982 YAMA RD350LC
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JanBros
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Re: Standard Spec YPVS 350 Barrels

#17 Post by JanBros » Wed Oct 04, 2017 3:32 pm

two-stroke-brit wrote: .
zeel gave approx a 5bhp gain on its own (with better curve ,not sure if he fitted a 4 degree key as well).
why bother fitting such a key when you have a programmable ignition :smt017
if it runs, you can race it !

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JonW
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Re: Standard Spec YPVS 350 Barrels

#18 Post by JonW » Wed Oct 04, 2017 8:00 pm

depends on if you need the +4 to get enough static angle, Ive used one on my 421 LC with a zeel for that reason.
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