the nova long stroke rod is 29.5mm the sirio one is 30mm. pin and crank pin is the same, you would have to lower the sleeve, not that easy. Th nova short stroke rod is 30mm also. and OS's

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What Nova rods are the 30mm short stroke ones? I take it they are not the R4-7 rods.

What about rod ratio and it effects?
What about change to primary compression?
Is it better to change port timing or increase/decrease area to obtain your goals for the torque curve?

How do you smooth internals after taking some material from Ports?

Thanks

I use a sponge sander attachment, then a metal brush wheels to smooth stuff down before polishing.

something like this...


They have a polishing kit in home depot with everything you need
(Camera Flash dulls out some spots)




Comes out very smooth, although polishing is not absolutely necessary.

Thanks i wasn't clear with what i said with internals i was talking about the inner of the sleeve.

Thanx

Oh, I have never had to smooth the inside of the sleeve with anything I use a highspeed carbide bit so when I take some material off from the outside and it gets to the chrome it doesn't leave any flash behind.

besides that you might be able to just touch the flash you have on the inside with a tiny cutter bit, or try to get to it from the outside and clean it off, watch that chrome!

On the inside of the sleeve when dremeled on the ports I use a small diamant grinding bit to take away the sharp edges. The chrome layer does not need to smoothen, when pinched you need to hone it with a rock to create new scratches, I was told you can find one in a automotive shop normally used for brake cilinders.

On the outside I do not do anything, after grinding they are smooth enough and there are pro's and cons to smoothen it.

Just interested in knowing the pro and con if you dont mind please .

A polished transfer channel will give a faster flow but a rough surface in the transfer channel will act as a mixing machine giving a better mixture.
So yes, there is a question which is better and I think a better mixture is more important for a faster and more powerfull combustion.

I qctually did grind with a diamond file but the este is quite sharp but i didnt how to remove that sharp edge

I qctually did grind with a diamond file but the edge is quite sharp but i didnt how to remove that sharp edge

That is correct its important to leave the channel rough for a good mixture but having said that its equally important to have good flow into the channel ie;smooth the bottom of the transfer port.there i go again giving away trade secrets you wont get that from murnan

i have been researching timing and port modification for almost a week now.

I have 2 old and almost dead cranks and severl old sleeves.

guess what i am about to do???


bordem at it's finest!!!!!

besides my dremmel 4000 could use a workout!!!


also i have a question about the induction port of the vspec crank. It is already beveled on the edges but i want to have it close a little bit later. Would it be better just to open up both sides??? or just take .2 mm off the closing side. I will also fang the throat. And i have a degree wheel and a digital level/angle finder so i can get the degrees on tdc and bdc.

i will also take some matierial off the con rod and make it smaller and put a better edge on it for flow.

I will fang the ports as well (minus the exhaust port)

I will however stay away from the port timing. and i will do small chages at a time and see how it goes. Besides the parts i have are garbage anyway!!!

I need some advice.
What will be the best way to modify a motor for smooth power curve (linear).
Some way that if you role the throttle, the power just become more.
I have a EB Mod Trinity.21, this motor is so amazing, smooth and so powerful.
They did mod the crank as well as the sleeve.
I have the tools to do mods,but now need some advice.