Kimble275

I have a modified .15 Yokoyo engine, pumping out 2.4-2.6hp. Cost me a bundle, but boy does my buggy fly! I have a smartech, it's 4wd so it's not out of control. Hit's 52 MPH with a radar gun, with 1 only gear at nearly full lean, and full throttle. Doing oh say, 38,000 - 42,000 RPM =) Chewed the teeth right off the first gear, so I baught a few extras before hand just incase. So much acceleration! The treads on the tires are now gone. I wish I had a camera/video thing, 1 gear! 52 Mph I'm so excited!

Aerobirdbrain

lol poor engine!

Tigger N. Bennie

Is that "Yokomo"? I was just wondering if it is the Yokomo RX-18, but that small block engine is only rated around 1.25 hp. http://www.yokomousa.com

Kuma

My Feedback: (1)

It's possible he ported the hell out of it, but 2.6 hp!? I don't think it's THAT much, maybe 1.5-1.8, and 42,000 rpm is quite high. That's insane, bet your engine won't live that long now.

Kimble275

Kokomo that's it. It may be a .18. Not sure. Not really into engine sizes. It is very loud. It had been modifed, the carbourator (sp?) port was been widened. Run really hot, but has an very oversized heatsink head to compinsate. Can't even put the body on, I can try, but it'll melt. From 2.4-2.6hp Aprox 90% lean. Oiled up every gas tank with 3in1 oil 40%nitromethane gas. 0% oils in fuel. I'm having lots of fun

Nitroaddict

hey kimble - i got 50.00 for ya via paypal if u can prove that engine is pushing out over 2hp. im calling BS on this thread. Whos with me>? lol

Tigger N. Bennie

Could it be a dream or someone's fantasy? I'd like to see a link to the manufacturer's home page of the so-called "Kokomo" engine, but what do you expect from a post that starts off "Hee Hee Hee". Don't light a match.

The Sirio 3.0 is rated at 1.9 hp and it is still in a small case.

Nitroaddict

true tigger, but sirio is know for a bit of exaggeration on hp numbers, even so - another .8 hp? sure.

lumburg54

The rustler goes 50+ with 1 gear as well. Not trying to discredit your set up, just saying it isn't too amazing.

XDestroymotorsX

could this number for this engine be right i found this engine on hobbypeople.com it is the XTM 21 Pro Racing Engine and the specs are
Displacement: 3.497cc
Bore: 16.27mm
Stroke: 16.75mm
Top RPM: 34,000
Power: 2.4hp
Weight: 10.68oz
if these numbers are correct i'm all over this engine it's only 99.00 bucks for it. also i dont know how good of make it is but hey i can fix that. what do you guys think?

Nitroaddict

xdestroy - that is a fair sport engine - remember, HP numbers dont mean squat in the RC engine realm. All manufacturers measure HP differently. Personally, for 100.00 investment - i would go with either the OS Max .21RG, or spend a lil more and get the Ofna Hyper .21 8-port

Tigger N. Bennie

HP measuring differences.... That reminds me of what I read on one of the R/C manufacturer's websites which wouldn't publish the hp rating on one of their engines. The funny thing was that I found the hp rating for their older engines. I then calculated their marketing of such and such "%" increase from their older engine. The result was almost identical when compared to the findings in one of the R/C magazines--if I recall correctly, a difference of about .05 hp. It seems to me it was all about marketing because if that company simply published the hp rating, more people may have purchased another R/C brand on that fact alone.

studysession

I talked to the Sirio tech support via email - they said even though it is a .15 engine. The case is of a .12

Just like the .25's and .26's using a .21 casing... they just bore it out big time..... Pretty cool if you ask me - personally I don't think any .15 or .18 will get that much HP out of it. If you do, good tell the manufactures how you did it so they will manufacture and sell .15 or .18's with that much HP.

Hell I have the Hyper .21 8 port and it puts out almost 2.5bhp.... The .21 8 port racing puts out 2.7bhp.... Get a .15 - .18 to out do a BB, that is impressive...

nitrofan

I agree. Im not doubting that it is fast, but the best .21 racing engines are in the 2.6 Hp range, and I do not see that kind of power from a .15 Especially since hes not exactly sure the name of the company that made it. If I had to guess I'd say 1.5 HP is more reasonable and would push his 1/10 scale to 50 MPH. It probably is very fast, but I just cant believe 2.4-2.6HP

petrolpixie

im calling bs on this one too. my thunder tiger pro .21 puts out 2.1hp and my novarossi puts out 1.2hp. i reckon this is total bs

nitroman88

My Feedback: (5)

Im just wondering how he even calculates those kind of numbers.

nitrofan

The word analysis is formed by the root word anal and the ancient Greek word ysis, meaning "to pull numbers from".

I copied this from another users signature, but I think it says all that needs to be said!!!!

Mugen Mbx5

I think it is bs. also. I have a Nova rossi P5 in a Mbx 5 and this engine is only rated at 2.6 Hp. That is a upper level BB. I don't see ANY sb making that kind of power. I doubt it even makes as much power as a RG .21(1.9) I have the rg and it would make a 1/10 almost undrivable from the power.

studysession

The Siro .18 - I forgot exact amount, but it is a small block that puts out a lot of power.

rclooney

not to spoit the argument, but isn't he using nearly no oil, this will increace power considerably as the oil can contaminate combustion and the manufacturers figures are based on the fuel they use. by using better fuel than they were tested with, a non-moded engine can push out a higher hp. if he used 1 or no head shims that will boost power a bit. not saying you are all wrong, but just a thaught.

nitrofan

I just think his estimates are too high. He might see a large power gain with the fuel and mods and so on, but 2.6 hp is just too high. I dont think its possible. Plus he said "it has four wheel drive, so its not undriveable" Sorry, but 2.6hp in a 4WD 1/10 would be undriveable. I have a modded 15 in my Inferno TR-15 that probably only puts out in the 1.2 to 1.5 range, and it can be hard to control at times. Plus, has anyone noticed that we go back and forth on this, but the author is no longer defending his original statement. I think we called his bluff, and he knows it. Thats why he hasnt said anything else

rclooney

OK. The sirio .12 puts out 1.8hp i think. look on tower hobbies. im only using maths and this may not be accurate, but in theory a .24 sirio will put out 3.6hp. so in theory 2.7hp from a sirio .18!!!!! i used a calculator to get these figures so with a performance engine (sirio), it COULD be possible. no i am not kimble 275 with another username. AS I SAID, BASIC MATHS. WORK IT OUT YOUR SELF. I am not saying he is right, just showing you that theoreticaly it is possible.

Nitroaddict

rclooney - im not even going to begin how looney that comment is.

"wow! so because a 3.0L Formula 1 engine puts out 1200hp, then the mustang 4.6L engine must put out 1836hp, right?"

doesnt work like that bro.

combine that with the fact that trinity measures the SAE hp numbers of the sirio engines off the chart, i can attest to you that the .12 sirio does not put out as much power as an OS .21RG

rclooney

this is from the tower hobbies site


NOTES FROM OUR TECH DEPARTMENT
This is the Trinity/Sirio .12 Size Standard Racing On-Road Car Engine.
This engine conforms to roar specs.

FEATURES: Constructed using aircraft alloys and CNC technology.
Slide valve carburetor insures greater response at the beginning and
end of the engine's power band which is suitable for on-road and
racing applications.
Rear exhaust.
ABC Construction
Turbo Style Crankshaft
4-Port Cylinder Design
SG Type Crankshaft
Manufactured in Italy
Three Needle Slide Valve Carb

INCLUDES: One Trinity/Rossi .12 Size Standard Racing On-Road Car Engine with
slide valve carb and copper shim, parts list and instructions.

REQUIRES: Glow plug.
Glow starter.
Tuned pipe and header: Depending on vehicle.
Fuel: Fuel with at 18% lubricant content and 10-15% nitromethane.
Most of the fuels we carry meet or exceed the lubricant content
required for proper operation. In the past the proper lubricant
content was 18%. But with new technology fuels like Red Alert
and O'Donnell, for example have a better quality of lubricant even
though the percentage of lubricant is lower.

SPECS: Horsepower: 1.8 @ 39,000 RPM
Weight: 220 grams
Bore: 13.7mm
Stroke: 14.0mm
Exhaust outlet diameter: 0.63" (16mm)
Distance between mounting holes opposite side: 1.26" (32mm)
Distance between mounting holes same side: 0.63" (16mm)
Distance from backplate to crankshaft opening: 2.10" (53.5mm)
Distance/top of engine to bottom of mounting flange: 2.99" (76mm)
Distance/ctr of exhaust opening/bottom mounting flanges: 0.98" (25mm)
Width of crankcase below mounting tabs: 1.04mm (26.5mm)

JiM 8.30.02
ir/kh


page is
http://www2.towerhobbies.com/cgi-bin...?&I=LXCKX7&P=7

Nitroaddict

rclooney - i am not stating that it didnt say that, i was aware. however, if u look at the Sirio website, they dont mention hp. when trinity imports the engine into the USA, they estimate what the hp will be with SAE spefications instead of metric. bottom line is trinity overrates all their engines hp numbers. the OS cv-r i use now in my TC is easily as powerful as the Rossi Pixie ROAR that i used before, and the hp numbers are over .5 less.