boyson ports or hog lower intake ports??

[Triplecrown421]

boysen ports or hog lower intake ports??

too who has tried either or??? or both?? both forms of porting are to attempt to get more flow to the crankcase. any thoughts on which may work better for the intake side of the cylinder.

im verying towards opening up the bottem on the intake windows just under the lowest point of the rings.....cuz because boysen ports seem like a B!tch to drill out.

This is what i mean:

what do ya think??

 

[sicivicdude]

too who has tried either or??? or both?? both forms of porting are to attempt to get more flow to the crankcase. any thoughts on which may work better for the intake side of the cylinder.

im verying towards opening up the bottem on the intake windows just under the lowest point of the rings.....cuz because boysen ports seem like a B!tch to drill out.

This is what i mean:

what do ya think??

That's not hogging the intake.... That's a sleeve installation where the intake window support continues on through the normal boost port.

You CANNOT do that to a normal engine. You can remove the "T" between the boost port and middle of the intake window with satisfactory results but there isn't much of a need to..... slightly enlarged intake windows do the same thing without losing the piston thrust area.

 

[Triplecrown421]

k i understand what your sayin... i got that pic off ebay when lookin at 240's, saved the pic cuz curious to what could be done to a stock jug. i got a right bend piece for my dremal and wanna start opening up some transfors ports!!

 

[Surfrjag]

So what would be the benefit difference be in boysens compared to that? I drilled in some boysens it wasnt hard at all

 

[sicivicdude]

Well, boyesen ports allow fresh charge to bypass the crankcase and go straight up the transfers (sort of). Cutting out the intake bridge and area under the boost port will drastically increase the intake port area but I promise, that's unnecessarily large even for a TOP tune engine. My dragbike cylinder still has the "T" and intake bridge. In fact, I didn't even narrow the bridge....

 

[Surfrjag]

So it would be beneficial to kind of angle the boysen ports up when most are angled down ?

 

[Triplecrown421]

So it would be beneficial to kind of angle the boysen ports up when most are angled down ?

im curious to this myself?

im veering towards the boysons if there not to bad to cut. i got some JB to drill through

 

[sicivicdude]

So it would be beneficial to kind of angle the boysen ports up when most are angled down ?

If you angle them up too much the size is severely limited by a lack of material in the corner of the transfer port and intake window. You'll bust out the side of the intake window in a heartbeat if your drill bit wanders.

 

[Awk08]

im curious to this myself?

im veering towards the boysons if there not to bad to cut. i got some JB to drill through

i would not suggest trying to drill the boysens thru the JB weld without being able to see exactly where you're aiming

 

[scotj77]

yeah good call awk. that could be difficult 1/8" the wrong way and you just made yourself a really nice paper weight

 

[sicivicdude]

yeah good call awk. that could be difficult 1/8" the wrong way and you just made yourself a really nice paper weight

That's the case even if you're not drilling through JB weld....

 

[scotj77]

I know that. but the jb weld will make it much more difficult to judge the proper angle to drill

 

[best]

I know that. but the jb weld will make it much more difficult to judge the proper angle to drill

I agree. It might be best to just start with a new cylinder. Try it with just the boyesens, and then add epoxy later if we want to try stuffing it. I think that is a better order to try things. Besides, we know this stuffer works, and can be repeated, move on and keep it as back up.

Yeah, I really question the angle into the transfer port. Do not want to mess up flow angles. Getting back to my "reedcage volume religion", if the volume is kept small there should be little flow through the boyesens as the piston opens the transfer ports on the downstroke. Maybe angle is a moot point? However the most flow is going to be on the upstroke and the crankcase is where it needs to go. I vote to angle the little baresters down.

I like Triple's idea of hogging the sides too.
Leave the "Tee" on the top. Full width bridge, it matches the piston anyway.
You do NOT want to cut anything off the weak piston skirt do you?
Open up the sides at the bottom of the port were the most action takes place.
Excellent idea.
Which one removes the least metal and keeps minimum volume in the reedcase and crankcase?

That pinch in is for the rings, below that does width matter?

The "draw" is when the piston is at the top of the stroke clearing this. ^^^^^

Yeah, we ain't drilling through that epoxy, we are starting fresh.
And I say we do both!

 

[blasterBruce]

I agree. It might be best to just start with a new cylinder. Try it with just the boyesens, and then add epoxy later if we want to try stuffing it. I think that is a better order to try things. Besides, we know this stuffer works, and can be repeated, move on and keep it as back up.

Yeah, I really question the angle into the transfer port. Do not want to mess up flow angles. Getting back to my "reedcage volume religion", if the volume is kept small there should be little flow through the boyesens as the piston opens the transfer ports on the downstroke. Maybe angle is a moot point? However the most flow is going to be on the upstroke and the crankcase is where it needs to go. I vote to angle the little baresters down.

I like Triple's idea of hogging the sides too.
Leave the "Tee" on the top. Full width bridge, it matches the piston anyway.
You do NOT want to cut anything off the weak piston skirt do you?
Open up the sides at the bottom of the port were the most action takes place.
Excellent idea.
Which one removes the least metal and keeps minimum volume in the reedcase and crankcase?

That pinch in is for the rings, below that does width matter?

The "draw" is when the piston is at the top of the stroke clearing this. ^^^^^

Yeah, we ain't drilling through that epoxy, we are starting fresh.
And I say we do both!

I can't wait to hear the results on this boyesen port and intake filler

 

[Surfrjag]

I just drilled some the other day it didnt seem hard

 

[sicivicdude]

Yeah, I really question the angle into the transfer port. Do not want to mess up flow angles. Getting back to my "reedcage volume religion", if the volume is kept small there should be little flow through the boyesens as the piston opens the transfer ports on the downstroke. Maybe angle is a moot point? However the most flow is going to be on the upstroke and the crankcase is where it needs to go. I vote to angle the little baresters down.

I like Triple's idea of hogging the sides too.
Leave the "Tee" on the top. Full width bridge, it matches the piston anyway.
You do NOT want to cut anything off the weak piston skirt do you?
Open up the sides at the bottom of the port were the most action takes place.
Excellent idea.
Which one removes the least metal and keeps minimum volume in the reedcase and crankcase?

You're almost forced to angle them down in a blaster cylinder because of the source of the material you're "shooting" them through. The area you're using is the intake side cylinder mounting tabs. The "meat" is down low, beside and below the bottom of the intake window. You can keep them nearly flat, but they're still going to tend to slope downwards slighty.

You can take out some of the intake window because the piston only blocks it at BDC. At TDC the piston is up and out of the way and the larger windows (via narrowed bridge) will allow flow into the bottom end with less windage. The one thing about the bridge is that it's harder to keep straight once you start working on it but it's easier to keep even. In other words, the lower outside corners of the intake windows can be taken out to gain window area as much as the bridge can be narrowed to gain the same area. However, getting both intake windows even is harder working two separate corners. The bridge can be chewed on, on both sides even though it's harder to keep each side even and pretty....