SManMTB

This is made for loop scavenged engines just like we use and by deafult your so called 'schnerle effect' is covered since the other name for the ports in a loop scavenged engine are also called shnerle ports.

SManMTB

FYI.

I measured an OS RG with OS T-2050 to the best of my ability and entered the data in the software and ran a simulation. The result was very close to the numbers given by OS when it came to peak hp and where in the rpm band that occured. So I's say it's a pretty awesome piece of software for the money.

supertib

just so you know I am not trying to knock it..I am only curious about it and its abilities to truly work with these types of engines....... Most likely engine manufacturers use a similar software to come up with their advertised HP,TQ and RPM ratings....... unfortunately when these engines hit an actual dyno the advertised specs are nowhere close to the engines actual output.......

does this software measure the port entry angles ? can you input a progressive port timing...as in a 4 degree ramped opening from leading to trailing edge of the transfer ? Most of the mods that I do focus on enhancing the loop scavenging of the motor.. Anyways my point is there is a fair bit of trickery that can be done at the port entries to change power and powerband.. So I am curious if this software takes any of those factors into account ?...

SManMTB

It surely isn't a $20000/year license but it's pretty damn good for the money. It uses theory based on Dr Gordon P Blairs work and it sure does beat guess work based on how things look.

You can enter a pretty much any port shape you want. All you need to do is break down the main shape in smaller portions and enter those. So in short, yes you can do a ramped timing profile.
I haven't figured out how to do an exhaust port as seen on the RB C6 for example but I think it can be done with some effort.

You can also input the angle of the port (top part) as this is the most important thing. The rounding of the lower part that is seen mostly here is not really a variable in this software. The top edge is far more important.
The popular 'fangs' are not there either.

You can enter bore and stroke in fractions of a millimeter but the resolution of the compression ratio is a bit coarse for my liking but it works.

The really fun part is to play around with the shape of the tuned exhaust and see all the pressure waves go back and forth. I made a pipe with two resonances for a broader power band but it would be a major pain to actually manufacture it from sheet metal.

I think the real strength of it is that you can get a feel for what different changes to timings, sizes and shapes can do and not the actual power numbers. It's very educational.


edit:
I think I remember you can define the intake ducts in detail, that would cover your question about the port edges.
I haven't played with it in a long time.

SManMTB

A simulation package combined with a dyno would be a great tool.

Colt4g63

I honestly dont like to dyno others engines. It is a big liability for my small business.. Even if one person says they dont care if the engine blows... Well that could all change when they realize they just lost a 350$ engine... So its something I steer away from. I use my dyno for what I bought it for and thats for my own R&D for engine modifications that I sell to customers. Now I test a few peoples engines that I know VERY well. I will test manufatures engines if they give them to me for the test.. I just dont like to be responsible for others/customers engines. Dyno testing can get ALOT more expensive then people realize... It can be very time consuming and the plugs and fuel alone add up FAST. That and im using a 6,000$ X-Dyno that has to get paid for somehow Im sure you all can understand where im coming from. Now I do post results of some of the engines I test from time to time. I do this to let people see what im putting out to my customers and to let them know when they go through AB Mods there getting there $s worth on PROVEN engine modifications.

SManMTB

There's another package called EngMod2T made by a South African which is supposed to be a bit better than MOTA but I haven't been able to find it. The price was around $400 (I assume US).

discocomedy

has anyone modded an os .18 tz? if so could you please post some pictures that I can use as a guide

yappyzk

hmm someone tell me if somthing is wrong ( well obviously )...
i modded my inferno gt stock engine, when putting back together the conrod looks like its hitting against the crankcase. is that normal? and now when pull starting, it feels like extra compression or somthing.
( i havn't started engine, just tried to pull to see how it felt ).

yappyzk

never mind, i fixed the problem. i had the thing on the wrong side.

Codeblack

lol. silly.



i have a question.

my buddy told me this story about how he put the sleeve 180degrees from the way its supposed to be put in... so the exhaust was at the intake..[sm=spinnyeyes.gif] the engine ran somehow.. how and why i have no idea. guess the intake/exhaust geometry wasnt that different, ha? has anyone else had this happen to them?? seemed like freak-show when i first heard about it.

yappyzk

haha, omg my engine is screaming as hell.... i havn't even touched the crankshaft yet..... everyone should try this if you dont got any $$ to buy a new engine ( but becareful or you'll end up buying a new one haha )
.. just AMAZING.. feels like a completely NEW engine
thing screams

dayglo

yes this porting does do wonders to motors. did a sh.28 over the winter and it is pretty crazy. it isn't over crazy though. the motor is pretty smooth too. off the line it gets up and goes. top end could be better but i think i'll try a 14 tooth clutch bell because it has enough torq anyway. for a cheap engine it definetly woke up.

yappyzk

has anyone ever lost the little e-clip that holds the pin and the conrod onto the piston?
i've lost mine, where can i get one? or wut to use as a substitute?

aftershockAL

wow this really is awsome i cant wait to try this with my engine! hopefully ill do it at the end of summer or right near the beggining of next summer that way im not anxiouse to try it

mr_kentu

hi everyone, i just hav a look at all of the previous page, and just a bit confused, which one of the sleeve port that should i follow?
some of them just port the standard hole available, and some of them make some new hole there, what im thinking, the more hole we make, will result in less compression isnt it?
another think, if me make some new hole, if we do not make some new port on the crank case, thats means noting and hav no effect at all right?
anyone hav the best pic of sleeve port complete with crank case port (m using force .15).
cheers.

brianr34

I was interested in doing my first porting job on a Novarossi N21B. If anyone has suggestions on what porting I should do, I would appreciate it. Has anyone modified this sleeve and/or crank and could put some pictures on here? Does anyone have pictures of a Hotmod N21B sleeve that they could post on here?

I was also considering trying to port a Sportwerks 21V2. If anyone has any experience porting that engine, I would also appreciate any input or pictures.

Thanks

JB COMP

Here's my latest engine. LMK what you think
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srad750c

[>:]he can you send me copies of the [email protected]

bluesilver

G'Day JB COMP

What engine are these from?
It looks like the Traxxas 3.3 motor.
Is this correct?

If so how has these mods effected the mid and top end performance?

Thanks.

skyline510

My Feedback: (9)

does anyone have some ideas for the 2.5r of traxxas want to try this mod?? guides/pictures will be a great help for a nub like me

thank you

Duke Cummings

i have a werks .28 that i would like to get a little more power out of but the numbers on it seem pretty aggressive they are as follows "induction" (crank) opens 32* after BDC . closes 58*after TDC for a total of a whopping 206* [X(] "exhaust" opens 32*after crank closes. and closes 80* after TDC for a total of 190* of duration. "transfers" open 50* after crank closes and 122* after TDC for a total of 140* duration . supertib , does this make any sense to you or am i referencing it wrong as far as coming from the crank ? i have it "0"d at top dead center.

JB COMP

I think you rote down your timings wrong, look at how I did mine here http://www.rcuniverse.com/forum/m_7452102/tm.htm

Duke Cummings

thank's jb , i'll do it again

nitro stan

hey whats up Duke