EVOLUTION

Discuss OS engines here.

http://www.osengines.com/

WheelNut

iTrader: (5)

Anyone else here mod their OS's too? What mods have you guys done?

EdwardN

iTrader: (1)

Changed timing on induction, exhaust and transfer. Relaped sleeve for bigger tapering on the bottom. Partly redirected flow on transfer ports, decreased crancase volume approx. by 10 %. Works great.

InitialD

Any numbers to go by?

Joehwee

iTrader: (3)

I just got myself a Mspeed TR 5+2, will be running it soon, will keep you guys posted on the performance.

InitialD

That must have costed you a bomb, Joe. How much did it set you back?

I'm told that the Kondo OS is a better engine than the MSpeed version...

CyrilJ88

Kondo?never heard of it.

alana07

iTrader: (53)

i heard Zac Modified OS TR5 porter is fast as well??

InitialD

In Japan, they are very famous. Look at the Japanese RC World magazines.

InitialD

Zac Modified? Never heard of it ! (j/k)

Anyway, has anybody tried the Zac or seen one on the track? Better still, has anyone seen or tried all three different OS varients i.e. MSpeed, Kondo and Zac?

Joehwee

iTrader: (3)

All the engine should be fast at that kind of prices, but I think Mspeed is a better buy, the reasons being;

Kondo - Modified engine out of the box, most work are done on the P&S and Crankshaft, minor work on the backplate, carb and conrod.

Zac/Kawahara - Not too sure who mod it, heard it was Kondo too, if that's true most of the work done should be simillar.

Mspeed - P&S are match before modification, mod are done on the P&S, Crankshaft, Crankcase, conrod and Carb. Backplate is also specially designed to increase flow and internal pressure. Crankcase is treated to increase strength and for better heat dissipation. Hestsink fin is machined on the button to improve heat dissipation. The heatsink is also replace with 7075 machined unit and is very light for low CG. Re-alignment of bearings in the crankcase.

But of cos the extra work done by Mspeed cannot guarantee better perfomance as they maybe for look only.

They are also other company doing modification in Japan such as NEXT and T-Force. However as far as I know ZAC TR and MT12 and T-force only have modified OS TR

Joehwee

iTrader: (3)

However I have put one of those Kondo engine on my wish list, may buy one next year if my racing budget allow.

EdwardN

iTrader: (1)

Sure, no secrets! Exhaust 166, transfer 126, induction 210 (sorry will not say when it open and close). Tapering .11 mm on sleeve lenght ( three tappers). Anything else I can give?

EVOLUTION

Yep,just pack it up nicely in its box and send it my way for tests ASAP !

EdwardN

iTrader: (1)

Man, I would love to, but it isn't mine property and already out of my posetion!