QEV or piston valve

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Gunner
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Sun Dec 30, 2007 1:26 pm

If you have 1" QEV and 3/4" piston valve that is built up well,what do you think,which one wins? :wink:
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MaxuS
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Sun Dec 30, 2007 1:37 pm

QEV wins for reliability and Piston wins for self satisfaction..
Although, over in the Uk, a 1" QEV will cost £125 ($250), but a 3/4" is almost dirt cheap.
I'd go with the QEV if you havn't built a piston before and don't know much about the inner workings of one, but then again, I'd be tempted towards the Piston because they're fun to make if you know what you're doing.
The QEV would have a better performance even if the Piston were to be made very well.
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ALIHISGREAT
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Sun Dec 30, 2007 1:39 pm

1" qev without a doubt, a 3/4" qev is almost certainly better aswell... this is because qevs have much lighter 'pistons' (which are actually more like diaphgrams) which allows fro quicker opening times i assume and a 1" qev would have a higher flow aswell.

edit: beaten :cry:
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MrCrowley
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Sun Dec 30, 2007 1:43 pm

Go with the QEV, it will allow you to have a 1" barrel without choking flow and it very powerful. The 3/4" piston would limit you to a 3/4" barrel and under, otherwise you choke the flow.

edit: doubley beaten :lol:
Last edited by MrCrowley on Sun Dec 30, 2007 1:54 pm, edited 1 time in total.
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dewey-1
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Sun Dec 30, 2007 1:52 pm

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Last edited by dewey-1 on Sun Apr 20, 2008 2:47 pm, edited 1 time in total.
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ALIHISGREAT
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Sun Dec 30, 2007 1:54 pm

another point is that piston valves often look better and cleaner than qevs
Gunner
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Sun Dec 30, 2007 1:57 pm

Oukeii...it looks like that QEV wins :)
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MaxuS
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Sun Dec 30, 2007 1:58 pm

ALIHISGREAT wrote:another point is that piston valves often look better and cleaner than qevs
Depending on how well they're made, if it's a ghetto Piston, then it won't look half as good as a QEV.
QEV's come all nice and shiny, Piston valves usually come across as grotty, bodged pieces of work.
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ALIHISGREAT
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Sun Dec 30, 2007 3:57 pm

yeah but most pistons look better than the ugly american qevs ghetto or not... wheras our lovely shiney qevs are beautiful in comparison to their american counterparts
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Sun Dec 30, 2007 4:07 pm

If you can't make a clean piston valve chances are your nice shiny Euro QEV is attached to a grotty bodged gun. A piston valve isn't even a visible component.
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ALIHISGREAT
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Sun Dec 30, 2007 6:02 pm

Hawkeye wrote:If you can't make a clean piston valve chances are your nice shiny Euro QEV is attached to a grotty bodged gun. A piston valve isn't even a visible component.
i haven't tired a piston yet, i might try and make a super fast qev-ish one though at some point :)
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HaiThar
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Sun Dec 30, 2007 6:05 pm

I prefer Pistons because of how relativley cheap they are to make. You're paying $30 updwards for a decent QEV, and you can make a piston out of items found around the house.
Kthx, BAI
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ALIHISGREAT
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Sun Dec 30, 2007 6:14 pm

HaiThar wrote:I prefer Pistons because of how relativley cheap they are to make. You're paying $30 updwards for a decent QEV, and you can make a piston out of items found around the house.
in the uk we can get 3/4" qevs for under £15, a decent piston would come to at least £10 i would have thought so the better performance and reliablity is worth it... but 1" qevs are £80 :? which is a shame because they would have god like earth shattering power :twisted: but the only point i see for piston valves is for large bores which in this case does not apply.
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Mitchza89
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Sun Dec 30, 2007 8:11 pm

Small bore guns are definately better with a QEV. Small pistons are extremely unrealiable (I've had my guns in the shop more then I've shot them!) They are just way too fiddly. 10mm bore and under, a QEV all the way. Anything upwards, a good piston valve will do you wonders but eh, if you new to guns, any QEV will do good, if you are good at making cheap small bore pistons then thats good to. If you are going to make a 2in golf ball gun, then ofcourse it's going to be piston valve. In the end, it's just how much time, how creative you are and how much you want to pay.
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mark.f
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Sun Dec 30, 2007 8:14 pm

ALIHISGREAT wrote: yeah but most pistons look better than the ugly american qevs ghetto or not... wheras our lovely shiney qevs are beautiful in comparison to their american counterparts
Hey! Maybe we think your QEV's look girly! That's right... giiiiirrrlllyy....

Heh... piston valves win past 3/4" in porting, because no company in their right mind would sell any valve above 1" in porting for less than 100 dollars.
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