A.C

iTrader: (1)

which type of engine fare better? comparing off-road .21 engine..

AXE rossi or Novarossi?

PTP Racing

iTrader: (2)

Thats like comparing apples and oranges and asking everyone which tastes better. Its going to be a matter of opinion. Ive had both and dont have any complaints on either. I will say though the AXE Rossi Cobra was probably the fastest engine Ive ever had.

A.C

iTrader: (1)

i was thinking of getting the cobra. izit easy to tune? and run stock at what % of nitro?

Mister-E

iTrader: (1)

AC,

Engine is easy to tune and stay tuned.
Nitro I'm using is 20% Byron, with 12% oil.

When driving hard, max temp is 250 F.

The pinch, is incredible. You can't turn the flywheel by hand!

I'm very happy with it and about to try and install the turbo head on it.

A.C

iTrader: (1)

mister_E

thks for the enlightenment. will def get the Cobra. i am running it on a technical track..

did u change the spring?

Mister-E

iTrader: (1)

Hi AC,

About to do some shopping for the springs.
I'm positive that this will solve the "slow pick up" (1,1mm springs).
Another note is that the used clutch bell should also match the track's characteristics. With the 48-tooth spur gear, a 13-tooth clutch bell should be the perfect combination for the engine

For now, another week waiting for the turbo head.
That's a long week

Jason Halvorson

iTrader: (22)

both are very good, but i would go with the novarossi, but there is nothing wrong with the axe...

Mister-E

iTrader: (1)

AC,

I changed the clutch spring to 1,1mm (gold) today.
What a difference, the engine felt a lot more responsive.
As mentioned, on a tight technical track, you dont want a slow reacting car.

Besides thicker spring, changed to 13-tooth clutch bell.

A lot happier now!!

AndyMoore

iTrader: (64)

Just buy a P5X or a VSpec.

A.C

iTrader: (1)

roger that...

PTP Racing

iTrader: (2)

The Cobra was a beast when I had it but I wouldnt really say it was easy to tune. I didnt have any trouble but a bunch of other guys who had them did. I think it might have been just they were too scared to lean it out enough. I used 1.0 springs and carbon shoes and never ever had trouble clearing any size jump no matter what kind of run up there was. Its a really strong engine through the entire powerband. If you feel you need 1.1mm springs to get enough bottom end my guess is your too fat on bottom. I also found that to get the best results from it I needed to tweak the midrange adjustment slighlty. BTW I used a JP-3 and 30% fuel without the extra included shim for plug I am pretty sure I used an Odonnell 77.

Mister-E

iTrader: (1)

PTP,

Thanks for the feedback. There are several points of improvements here, which I could spot, when comparing with my setup.
I'm using EFRA 2027 pipe which equals the JP-2 pipe (high end pipe).
Nitro percentage is 20% (Byron). Glowplug used is OS R5.

Currently, I'm waiting for the JP3 pipe to arrive which will provide me more bottom end power with the Cobra.

Concerning adjusting the midrange, do you have any suggestion how to tune it correctly?

What about the turbo head, any experience with that?

Thanks in advance for any feedback.

Jason Halvorson

iTrader: (22)

GHETTOTEACHER

Mix a Novarossi, add Duratrax long life shoes (Aluminum carbide mix!) with two 1.0 and one 1.1 spring. Very nice acceleration and control. Anybody else mix clutch springs ?

Zaint

iTrader: (3)

Cobra is the best! ANyone who wants to see it's power and speed check my vid. hope you'll like it.

If i'd buy another engine it would be another cobra. this time i'd get a standard one and mod it myself.

http://www.rcuvideos.com/item/FSF410SL7LVNQ8C0