anyone done it?...probably not, but what are the results? not just increasing the left-right size of the existing holes or connecting them(pointless)
gila piston window
Re: gila piston window
longer intake duration, scavenging, fresher charge...
Re: gila piston window
i might do it. ive got a metra piston in it right now (with the holes, of course).
are you using a metra piston with the side gaps as opposed to the gila piston without them?
Re: gila piston window
If you made two windows it would leave material in the center for absorbing piston thrust as it flings around
Re: gila piston window
you could change your intake timing a little and not make it just 360 degrees intake timing. try something new. many reed valve kits, like the polini have 360 intake timing. ie. the piston never closes the port, only the reeds. the gila's piston closes the port for about 70 degrees if i'm guessing right, use that to your advantage, don't open it all the way up yet.
Re: gila piston window
Wise counsel. In a way the gilardoni is a hybrid. Half piston port and half reed valve-----If I should put words in your mouth Zack
Re: gila piston window
they're all "piston port" just ingenious design to act like a case inductions reed intake, compormises the piston design that why we see so many seizure like polini's. The piston the kit comes with says metra kit on it and it has side windows. Jennings doesn't promote cutting a rear window in a piston in lack of piston integrity but what what i drew i want to keep the rear intact. so it wouldn't be a full 360 but still keep its structual integrity. besides messing with timing the only thing i see is to open the boost port up slight as it flows downward but it may create more turbulence in the cylinder. I'm relying on my case it's ported absolutly beatiful and the best components/ tuning to have a very fast bike.
Re: gila piston window
thats good youve got a metra piston. I like it better than the original gila piston. Its way thicker, heavier, and the side windows are awesome.
I think cutting a window might be helpful in this case, and the piston seems like its pretty damn solid and would hold up just fine, especially the way youve drawn it.
Re: gila piston window
I will second that the Gila piston is a little thin in the crown
Re: gila piston window
They're mahle pistons that say metra kit on the crown, I have a piston out of the mk 80 and it doesnt come with side windows thats also mahle. the last bit batch that came it had oil holes for the wrist pin and the new ones don't
Re: gila piston window
still waiting to see an ultra fast gila.
I have my doubts about that kit. I should really get to work on mine, but my mind has been on big boy bikes lately. One of these days....
Re: gila piston window
im just saying i have both one of the older gila pistons, as well as a metra piston with side windows (the old gila piston did NOT have them). Right now the metra is whats in my kit.
I think the gila just needs a little work and then we can see some real power out of the kit. I did a half assed job portmatching after grinding the case out, and i was still able to hit 55 on 18x45 gearing
Re: gila piston window
this is the second gila ive done and we've barely tuned it 15 x 45 is in the 50's. I have no doubt this is the fastest standard kit for puch. mine is going to be an e50 original 3 shoe, louis veton stuffed reed cage, top crank, simonini, want/waiting on another hpi and tm24. cleaned up the kit and case came out almost flawless
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yeah like i said my case matching is poopy. and ive only got a 19mm phbg.
Re: gila piston window
wow, that is some gorgeous case matching dude.
What bit did you use to achieve such an effect?
Re: gila piston window
.Damn.
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omg.
Re: gila piston window
is that not a massive hole you have in the right transfer?
Re: gila piston window
yea, that might be an air leak.
silly bearing lubrication.
Re: gila piston window
Re: gila piston window
let us know how it works, im super interested.
Re: gila piston window
might this have the same effect as incresing the up-down of the two holes?
Re: gila piston window
should give better lowend i think
Re: gila piston window
So... did the piston window help?
Re: gila piston window
really interested in how this works out. how many mm did you end up extending the duration?
Re: gila piston window
actually i don't think it would give better lowend unless u had really soft ass reeds to go with 360 intake timing. It's probably gonna magnify the reed timing effects, what ever they are set up tp be.
yeah wat happened? according to the tuning guide u hit 65mph, but andrew said it was sluggish on the hills, but he has a 2 speed right? so watever. really curious to what that window might be doing, and have u ridden jimmi's (or any non modded) gila b4 for comparison?
Re: gila piston window
Bump for people that need it.
Wasn't there a version #2 or #3? of these..
Re: gila piston window
thanks ed.
Re: gila piston window
10-4 to nice to be inside..
Re: gila piston window
I is fucking hot outside today and I have a cold!
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