True tunned pipe length

The earlier version is available free!!!:rolleyes::eek::D
Well thats good to know,There are many free software programs available now that I've not used just because of the time envolved in checking their validity I'm a little ocd that way and have to know that the end result is correct so I stick with the IWT Racing one that has proven to concure with manualy doing the math.
 
Well thats good to know,There are many free software programs available now that I've not used just because of the time envolved in checking their validity I'm a little ocd that way and have to know that the end result is correct so I stick with the IWT Racing one that has proven to concure with manualy doing the math.

I read some reviews and it appears good but the early version is not simpatico with my windows program.
 
These values are a starting point for proper pipe length (tunned) to the engines actual exhaust port timming and rpm.
First we need to know the exhaust ports open duration in degrees.Messured from deck to top of window.We'll start with the stock generic or older 38mm stroke and 85mm (short) rod @ .7 crown to deck.
height of window druration wave speed rpm length
28mm = 140.66 x 1,700 divided by 8,000 = 29.89"
27mm = 147 .48 x 1,700 8,000 = 31.33"
26mm = 154.10 x 1,700 8,000 = 32.74"
Now since I've yet to see a stock exhaust port higher than 26mm that should cover it,So we will move on to the stock 40mm stroke 89mm rod (long) also @ .7 crown to deck height.
28mm = 149.99 x 1,700 8,000 = 31.87"
27mm = 156.21 x 1,700 8,000 = 33.19"
26mm = 162.29 x 1,700 8,000 = 34.48"
Now we can look at a modded generic or older 38mm stroke and 85mm (short) rod @.7 crown to deck.
25mm = 160.54 x 1,700 10,000 = 27.29"
24mm = 166.84 x 1,700 10,000 = 28.36"
This is as far as I will go here since I can't recomend going above 24mm due to loss of torque.
We will now look at a modded 40mm stoke and 89mm (long) rod @ .7 crown to deck height.
25mm = 168.25 x 1,700 10,000 = 28.60"
24mm = 174.10 x 1,700 10,000 = 29.59"
The rpm used here is not the final rpm rather the peak rpm before power starts to fall off the rpm may still climb above this point depending on the type of pipe used.Next we can look at the chamber area's and cone angles to help determine the best style or type suited to the aplication. I will try to get to that soon as this takes me awhile to put up here LOL.
 
At the moment I have a Honda cr80 pipe which needs to be recurved at the cylinder end to fit so length is the most crucial numbers I need, so thanks, but I am looking forward to the pipe shape numbers.
 
It looks ok but I'm not going to pay 35 bucks U.S. to only be able to use it twice in a 365 day period as per the piracy statment attached states.



i use two stroke wizard. always given me working results. i did prefer version 3 to version 5, and tried the "duel power" on one pipe with fairly inconclusive results. maybe on my NSR150 when i rebuild it (again...) plus finding which percentage of open space mesh is ideal... what hole size/shape, etc. plenty of variables to stuff around with.

as for the use two times a year? no. read it properly. its INSTALL on a PC system twice in a year.

once installed you can use it as much as you like...

anyway, it often comes up on special every now and then. i think i paid $10.

you also need to download "cone" or something similar. i think my version of cone now takes fifteen minutes or so to open. an extra second every day or something like that...

enough time to go make a coffee and have a smoke :)

be prepared for a heap of work laying out the pipe and welding it up. 180gsm paper is ideal for testing the final shapes before cutting any steel.

and my pipes were always a slight compromise because i would fiddle around with the peak rpm and power just so the lengths/diameters would result in nicely rounded figures. hard to cut things to 0.1mm accuracy. the quote i got for a local laser cutter was absolutely ridiculous.
 
These values are a starting point for proper pipe length (tunned) to the engines actual exhaust port timming and rpm.
First we need to know the exhaust ports open duration in degrees.Messured from deck to top of window.We'll start with the stock generic or older 38mm stroke and 85mm (short) rod @ .7 crown to deck.
height of window druration wave speed rpm length
28mm = 140.66 x 1,700 divided by 8,000 = 29.89"
27mm = 147 .48 x 1,700 8,000 = 31.33"
26mm = 154.10 x 1,700 8,000 = 32.74"
Now since I've yet to see a stock exhaust port higher than 26mm that should cover it,So we will move on to the stock 40mm stroke 89mm rod (long) also @ .7 crown to deck height.
28mm = 149.99 x 1,700 8,000 = 31.87"
27mm = 156.21 x 1,700 8,000 = 33.19"
26mm = 162.29 x 1,700 8,000 = 34.48"
Now we can look at a modded generic or older 38mm stroke and 85mm (short) rod @.7 crown to deck.
25mm = 160.54 x 1,700 10,000 = 27.29"
24mm = 166.84 x 1,700 10,000 = 28.36"
This is as far as I will go here since I can't recomend going above 24mm due to loss of torque.
We will now look at a modded 40mm stoke and 89mm (long) rod @ .7 crown to deck height.
25mm = 168.25 x 1,700 10,000 = 28.60"
24mm = 174.10 x 1,700 10,000 = 29.59"
The rpm used here is not the final rpm rather the peak rpm before power starts to fall off the rpm may still climb above this point depending on the type of pipe used.Next we can look at the chamber area's and cone angles to help determine the best style or type suited to the aplication. I will try to get to that soon as this takes me awhile to put up here LOL.
Nice info. I'm going to have to remember this thread so I can resource it later. Are the lengths your giving from the piston face to the mean reflection point in the diffuser?
 
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