seeee....you CAN port with a chisel!
03-14-05, 07:16 AM
#26
Originally Posted by GUITARJUNKIE28
for fear of someone paying a visit to my house with a gun (or pickup truck), i'm not going to say who did this work here, but anyone can pm me and i'll tell you with the understanding that you keep your mouth SHUT!
I bet its "JV." PM me otherwise.
03-14-05, 07:47 PM
#30
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i like to take photos of all the ports i do (even though ive actually only done 2 motors so far and one was for me and the other was for a friend) that way you have proof of the quality of work.
03-14-05, 08:49 PM
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If you dont mind, I would love to have a template of your bp and/or street port.... Also, you wouldnt happen to have some #s for it or even just some info on how long shes been running. More people should be willing to share their spec's on porting.
03-14-05, 09:19 PM
#36
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the half-bridge from my avatar did 400 whp @ 13psi on a 62-1, 1.15 p-trim, npr intercooler, haltech e6k.
it ran fine for ~ 6k miles, then some asshat stole the car.
www.rotaryheads.com/porting
look at that and tell me what kind you want, but the port from your other thread is really similar to my big sp. most of the work is done where you can't see it though, so templates aren't really the best way to do things unless they come with a video or really detailed instructions.
it ran fine for ~ 6k miles, then some asshat stole the car.
www.rotaryheads.com/porting
look at that and tell me what kind you want, but the port from your other thread is really similar to my big sp. most of the work is done where you can't see it though, so templates aren't really the best way to do things unless they come with a video or really detailed instructions.
03-14-05, 09:39 PM
#37
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Looking at that site makes me think I'd need to "clean" out my UIM/LIM too.. is that a correct assumption? I'm definately interested in the street bridgeport, as it says its still streetable. I'd love for you to send me a pic or something actual size to overlay and grind.
03-14-05, 10:01 PM
#38
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I would really like to have the bp that you do w/out cutting the housing. I take it you do the same port size on the middle plate, as the secondaries?? I would also like the big street port just to compare. Looks like you cut even closer to the corner seal than I did. I guess im just a *****...
03-14-05, 10:11 PM
#39
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most guys fear the unsupported side seal. i just give the edge a big-*** radius when i go that far. i've never had a problem with it yet.
i'm working on some machining on the rotors with a new side seal design that will allow the port to be brought within a few mm's of where the rotor housing will be. for that one, you'll have to turn the apex seal on your rear rotor around backwards!!
but that's at least 6 months away...i'm still trying to get longer side seal lengths from mazda, but to no avail thus far.
for the bridgeports, i don't advance the port timing in the main port... the bridge takes care of that. and also, i'm working on a new kind of bp-where the "new" port is gonna be really small, but the whole port will outflow what people are doing now.
i'll be getting a flow-bench together in the next while, so everything is going to be very thouroughly tested--not only for flow numbers, but for flow direction, and interaction with the other port(s) and rotor position.
so far, i've done what works (i'm by no means an "expert"), but i really want to improve on the port design. you can have a higher flowing port without making it huge.
i'm working on some machining on the rotors with a new side seal design that will allow the port to be brought within a few mm's of where the rotor housing will be. for that one, you'll have to turn the apex seal on your rear rotor around backwards!!
but that's at least 6 months away...i'm still trying to get longer side seal lengths from mazda, but to no avail thus far.
for the bridgeports, i don't advance the port timing in the main port... the bridge takes care of that. and also, i'm working on a new kind of bp-where the "new" port is gonna be really small, but the whole port will outflow what people are doing now.
i'll be getting a flow-bench together in the next while, so everything is going to be very thouroughly tested--not only for flow numbers, but for flow direction, and interaction with the other port(s) and rotor position.
so far, i've done what works (i'm by no means an "expert"), but i really want to improve on the port design. you can have a higher flowing port without making it huge.
03-14-05, 10:18 PM
#40
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Awesome, yea if you could scan a template of your BP, that would be helpful. Looks like your doing some really good work, keep us posted on your flow bench results
03-14-05, 10:25 PM
#41
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they're at least a month off, but will do.
templates will take me a while to make cuz i'm so busy, but i can throw a piece of paper over a port and use a crayon to transfer the shape if you want. i think i've got a small and large streetport, normal bridge, mild sp renesis, and bp renesis in the garage right now.
then a couple re/20b ports. those engines have a really nice venturi effect, so you can get away with making the actual port orifice a little larger without killing velocity.
templates will take me a while to make cuz i'm so busy, but i can throw a piece of paper over a port and use a crayon to transfer the shape if you want. i think i've got a small and large streetport, normal bridge, mild sp renesis, and bp renesis in the garage right now.
then a couple re/20b ports. those engines have a really nice venturi effect, so you can get away with making the actual port orifice a little larger without killing velocity.
03-17-05, 07:57 PM
#45
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I'm curious why you say the opening of the exhaust port needs to be rounded rather than flat. I've seen lots of varations of port openings. I've seen lots of high performance 2-stroke motorcycles cylinders and the initial opening of the exhaust port is much larger than the middle or closing. This is to allow the high pressure gas exit faster at the begining of the exhaust cycle.
But I must admit, the porting is bad.
But I must admit, the porting is bad.
Originally Posted by rotarygod
I say expose the person who did that crap to save others. It's doing everyone a favor.
Besides the fact that the person who did that can't port worth a damn, the shapes aren't even close to optimal. I'm willing to bet that engine actually flows worse than stock. It is possible to make ports larger but have them flow less. The exhaust port is done completely backwards. The top edge should be the flat one and the bottom should be the rounded one. Not the opposite. That is absolutely horrible for airflow and it probably lost at least 50 cfm that way. I'm not even going to touch the intake ports.
As I'm fond of saying, do you want your engine builder airflow testing or airflow guessing? It's amazing how many people still choose the wrong one!
Besides the fact that the person who did that can't port worth a damn, the shapes aren't even close to optimal. I'm willing to bet that engine actually flows worse than stock. It is possible to make ports larger but have them flow less. The exhaust port is done completely backwards. The top edge should be the flat one and the bottom should be the rounded one. Not the opposite. That is absolutely horrible for airflow and it probably lost at least 50 cfm that way. I'm not even going to touch the intake ports.
As I'm fond of saying, do you want your engine builder airflow testing or airflow guessing? It's amazing how many people still choose the wrong one!
03-28-06, 01:03 PM
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Originally Posted by GUITARJUNKIE28
how big do you think this port is?
people tend to pay attention to the least important things. a big, gaping hole isn't gonna build as much power as a smaller port with good runner work done.
almost every ported engine i tear down needs to be cleaned up, or fully redone.