nitroracer20

buy a epic big bore .18, put the red hpi pinion gears on it and buy a ms airfilter and your set(maybe)
Good Luck

Saboteur10573

Rotational mass reduces acceleration, but will add top speed. Less weight doesn't mean more top speed. The vehicle will just accelerate quicker to the top speed and there is less work for the powerplant to do. Most 8th scale onroads only touch 60-70mph on a track. That's about it. With a change in the gear ratio they can probably get to 80mph or maybe 90. That requires testing and so on. Also with a taller gearing it reduces acceleration.

Saboteur10573

BTW- The Epic .18 doesn't make enough HP or RPM to get to even 70mph. It's power is about the same as an MT12..aronud 1.11hp or so and does upto 36rpm or so.

lax195

My Feedback: (2)

THe Sirio EVO 3 Port is a high winder, VERY nice engine. A little more power than the 5 port, but the 3 port isnt ROAR legal.

Hey, what about NITROUS![X(][X(][X(]

Saboteur10573

Nitrous won't work in these engines.

lax195

My Feedback: (2)

OOOOOO YES it will. I have seen nitrous kits put in Savages with a 3 channel radio and when the guy opens the nitrous bottle up... BOOM the engine SCREAMS and accelerates like CRAZY. But you cannot do it for long or else you will start blowin gaskets and seals.

Saboteur10573

I'd like to actually see that for myself. Otherwise I refuse to believe it. Most of the time it's just special effects. I don't waste my time with superchargers, nitrous, or boost bottles. No dissing anyone, but they aren't needed and a waste of money. Only for cool effects. Still with these 2 stroke engines you can only do so much. I've seen a vid of a Tmaxx claimed to have nitrous but it just had a louder pipe, same 2.5 heatsink, but a different engine underneath. The guy drove slow for a bit, then hammered the throttle. Talk about cheap.

Saboteur10573

PS. Nitrous doesn't mix well with Nitro methanol. It hasn't been proven by ANY very knownledgable person I've met in person and on the net. Only few months ago did they actually find a supercharger to actually work...improving the engines performance. Good for horseplay, but Nitrous...heh...thats just it...heh.

kwong2001

My Feedback: (2)

That's more half right. If you add a 3 speed as opposed to a 2 speed or single speed, you will get better acceleration (assuming final drive is the same), but your top end won't be any different, it in fact could be less. When you add more gears, all it's doing is ensuring the engine stays THAT much more in the powerband as it accelerates. Each gear not being used is essentially dead weight and makes it THAT much harder for the engine to max out the gear it is currently in.

Especially when you get in the +80mph range, forces become a lot harder on the car. With a 3 speed geared for 80-90mph, by the time you hit 3rd, you engine is struggling enough to accelerate. 1st and 2nd aren't doing anything to help whatsoever. They are actually hurting it by being dead weight. If you have a single speed, and the same final drive compared to a 3 speed, you'll have no dead weight to hold the engine back from accelerating the car, and will increase your chance for a higher top speed.

3-speeds, or even 2 speeds are only there for acceleration. The only time they would come into play is if your engine drops so far out of the powerband that it can't accelerate the car and needs a way to stay in the powerband to keep accelerating. Hence, the need to add additional gears to keep it within a level of the powerband to still accelerate the car more, or at an acceptable rate (ie bashing in a small area). But as long as your engine has enough power to accelerate the car, through it's entire geared potential, and you have the room, a single speed is all you need.

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And quite frankly, if you want a CEN ct4s, which already goes 74mph, to go 80mph, you would be better off just adding a few more pinion gears to the clutch bell. The final drive won't be THAT much different.

kwong2001

My Feedback: (2)

I believe R/C Car Action or some magazine did a review of that one Nitrou System for r/c's. They basically said they got very little gain and had A LOT of trouble getting the engine to keep proper mixture. Also, they never found the right glow plug, even after contacting the manufacturer/designer of the system.

Saboteur10573

Yeah, I can't remember either. Thats why I have a hard time believing that Nitrous will work. I mean it's obvious..if the pro's cant do it, what makes everyone thing some average person can? Oh yeah forgot about that with the 3 speed. I mean the Fusion could probably do 70mph anyway or around there with a 2speed. Just have the gears properly setup, however it may have poor acceleration in 1st gear. That's probably the reason why they made the 3 speed instead.

American Muscle

ok i know a freind that has got his nitro 4-tec up to 72 mph!! and isn't the nitro 4-tec 2.5 a .15? i kno that the hpi gears are set up for more acceleration than they are top speed but still i can get new gears set up better. i want to get a sirio .12 i think that will get me in the 60's.

Saboteur10573

At one time the TRX 2.5 (a .15small block engine) was the fastest .15small block around with 1.33HP@34,000rpm or so. The RB V15 owns it now. You can get to 70mph yes. Takes some time, money, and a lot of road space.

T-MAN-iR

CEN claims with the optional 3 speed transmission (if and when it ever comes out) it will do 80. And its not a small block, its a 2.5 Big Block with 1.5hp.

kwong2001

My Feedback: (2)

lol, a .15 is not a big block

tRaXx-aSs

Im sorry but a .15 could be a big block..
this proves it.. http://www.nitroreview.com/TheDatabase/homeengines.cfm scroll down till you see .15 big block

kwong2001

My Feedback: (2)

That doesn't prove anything, it's still the same size engine. Oh and if you wanna get technical, they rated that Cen NX-15 at less than 1hp.

Mr D

lax195 .... and the 5 port is ROAR legal????? or did you confuse your ports??? he he he Any way you put it they are both nice engines for the money...

Polar_Bus

Interesting still photo. If in fact that car is doing 89 mph, than how the heck did a touring car survive that substansial short "dip" in the road that's in the photo about 50 feet out in the picture without violently sending the car airborn and barrel rolling the car???? Personally I think it's bull. Radar guns can freeze a previous reading (like from a automobile doing 89 mph) Strictly my opinion)

kwong2001

My Feedback: (2)

haha, OMG Polar, I was wondering that too yesterday. Did you also see how blurry the whole damn picture was? If it was doing 90mph, you would hardly be able to tell what the paintjob was on the car, much less tell it was a touring car.

Saboteur10573

Exactly. ITS FFFAAKKKEEE!!!!! LOL. OH yeah, there are .15 small blocks, and .15 bigblocks. The .15bigblocks are mainly used in the Nitro 10th onraod (235mm class) and have been around since the 235mm class. BTW, I do recall that being a .15bigblock they used in the Cen, but just a sport engine.

kwong2001

My Feedback: (2)

Then what's the difference between a .15 small block and a .15 big block? They have the same displacement!

Saboteur10573

They are the same displacement, but the .15BB is in a .21case. Thats why .21 engines can fit those 235mm cars.

kwong2001

My Feedback: (2)

So the .15 big blocks share the same blocks as a .21 big block? Are the dimentions the same, but with more metal to accomodate the smaller sleeve and displacement? Does this mean the CEN can't accept a standard small block? Same with any car that has a big block .15? The .15 big blocks have .21 motor mount bolt patterns and the clutch nut threads are .21 size also?

Saboteur10573

Pretty much. Most of the mounting demimensions are the same on some .15BBs and .21 engines. Few differ. I bought a clutch nut that was for an OS .21 rg, but it fit on my MT12 with no problem. It's like the SG cranks for some .12s, .15 big blocks and .21s have the same threading size. I'm not sure about the mounts of the Cen, because I never really take much interest in their cars. Have to contact them to ask if a small block will fit.