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turning my attention back to the neverending rally restoration now that the et3 engine has been replaced right down to basically everything but the xmas tree and axle...

any tool suggestions for clearing out iron material on cylinder ports? something tells me my dremel won't cut it, so to speak. specifically, i need to match up the cylinder intake port to the case (port is squinty and weak).
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i have no experience cutting cases but i have seen quite a few over the year

the dremel is great because it is more forgiving than a air tool

if you make a mistake with the dremel, not to bad

you make a mistake with a air tool and your screwed

imo
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What ports are you trying to clean up? On the rally only the 3rd transfer port (transfer port, remember that term there will be a quiz) interfaces with the cases and unless you are filling the cases to really match the port there's no point. The 3rd transfer port (sometimes called a boost port) only flows about 5% of the total so any gains will not even be noticed.
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people enlarging ports typically use grinding bits of various shapes on a dremel or die-grinder.
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Dremel with one of those bendy extender things that make it longy so you can do reaching on the insides.
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CORSA IFP wrote:
Dremel with one of those bendy extender things that make it longy so you can do reaching on the insides.
Yeah...been wanting to get one of those, just nver got around to it. That's a good idea, though.
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I'm fond of needle files as well.

Also, don't mess with the transfer ports where they open above the piston other than chamfering the edges.
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oopsclunkthud wrote:
What ports are you trying to clean up? On the rally only the 3rd transfer port (transfer port, remember that term there will be a quiz) interfaces with the cases and unless you are filling the cases to really match the port there's no point. The 3rd transfer port (sometimes called a boost port) only flows about 5% of the total so any gains will not even be noticed.
boost port, eh? damn, i wonder if it's worth opening up that cylinder port to match the case there (to be clear, jimmy, the case port is actually bigger than its correlating cylinder port...not the other way around that would mean cutting the case up). i guess the question is "could i sleep at night without doing so?" depends on how quickly and easily i could do it. i have the flexible dremel attachment...is there a bit for iron?

after playing around with my et3 to the exclusion of my rally motor for the last several months, and then getting back to the rally engine the other night...man that sucker is heavy duty. the rings are like bracelets and the jug is damn near as big as the case. i can't wait to fire it up.
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Don't open the boost port to match the case. The case is only open wider than the port on one side. symmetry is key so the only way to improve this would be to fill the cases to match the port, not the other way around.
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oopsclunkthud wrote:
Don't open the boost port to match the case. The case is only open wider than the port on one side. symmetry is key so the only way to improve this would be to fill the cases to match the port, not the other way around.
good enough then. frankly i wasn't looking forward to grinding iron for hours. i'll just clean up that sucky seam and be done with it. i think the transfers are factory chamfered. will have to have a quick look... then attend to the piston ports with a mild touch and get this damn motor back together.
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i'm not the one to ask here

i am interested but i think you are in much better hands with patrick

i will add this, my et3 ports are so perfect from the factory that when i pulled the head and looked at the piston

there were two carbon free areas where the exhaust ports were (pic)

what i'm getting at is you can do a perfect tweak or you can create a turd

go slow and small steps and and just when you think thats enough you may have done too much already

follow good advice to the t
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oh hell yeah, patrick's my go to dude, and is for many others in these parts. he lent a hand and advice years ago when my first smallframe seized while idling in front of first kick where he just happened to be. i think the last three calls were:

"hey patrick, does turning it out or in richen it..." (he went to the socratic method here..."is the adjuster in front or behind the slide")

"hey patrick, do you have one of those exhaust manifold elbow thingies..."

"hey patrick, do you have a spare crank?" (patrick loves my hail mary calls)
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patrick 's the one that told me about the areas on my et3 head

i run my 19/19 on the rich side

2 1/2 turns on the mix

80 main

f--kin love that bike

easy 53 all the time, for ever

48 - 50 into the wind

f--kin love that

do you know which head you have on yours aaron
primevera
primevera
et3 stock (jocky cap)
et3 stock (jocky cap)
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bike was kitted when i got it. it's got a malossi head.
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aaron h. wrote:
bike was kitted when i got it. it's got a malossi head.
oh

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