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Which engine is better for a maxx?

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okihost

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I am trading some car parts for a maxx and I have two offers, both are pretty much the same setup just one has the stock 2.5 and one has a sirio .18, Which one would you say would be best for me?
 
the siro .18 the only thing is there hard to find parts for. i dont have any problems keeping it tuned. temps run around 210 to 230. awsome power. the 2.5r is still a good mill when their tuned good. but I've had lots of tuning probs with mine. hope u get a good deal.
 
nitehawk403 said:
the siro .18 the only thing is there hard to find parts for. i dont have any problems keeping it tuned. temps run around 210 to 230. awsome power. the 2.5r is still a good mill when their tuned good. but I've had lots of tuning probs with mine. hope u get a good deal.
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Yeah I am trading about $250 in car parts for it, less than a quart through it and some aluminum upgrades, FM radio so I can't wait :)

Is the sirio .18 discontintued or just most places don't carry parts for it.?
 
okihost, I the sirio .18 engine is italian made, so you know it is higher quality than the trx2.5 right off the bat. As far as the horsepower for each, the sirio .18 has 1.9HP and the trx2.5 has 1.6HP. I have never owned either engine, but I hear that most of the trx2.5 engines have tuning issues and don't hold one very well. Both engines are good, but the sirio has more power, hands down. Go with the sirio and you won't be dissappointed.



rbmaxxbasher said:
I have the omega .21 x2 drop in for mine. Lots of torque.
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I really can't stand it when people say stuff that has nothing to do with the thread at hand. I am glad that your engine has a lot of power, good for it. That had nothing to do with the question though. Your post would've been a whole lot better if you said that plus "hey, but out of those two engines, I would definitely prefer (engine) because (yatta yatta)"
 
.21Rc10GT said:
The trx 2.5 has 1.33hp. :smoke:
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I got some false information then... haha I should've known, it took me like an hour of searching on google and all I found was one person in a forum claiming it had 1.6hp. Sorry about that! Thanks for correcting me.
Later
 
Thanks guys, it is shipping tomorrow so hopefully by this weekend I will be bashing again :)
 
Awesome, the only thing I can say with the Sirio engines is that if the drive shafts are plastic, they're gonna twist alot. I've seen people blow diffs, even trannys with Sirio engines, but they might have done that themselves. One thing I noticed with all of them though that they twist the drive shafts and axles pretty bad. Just something you might want to look into so your not replacing that stuff constantly. Enjoy that truck. :)
 
Make shure the diffs are properly shimmed up. I just put a Sirio .18 in my Maxx, and it screwed up one of the diffs before it was even totally broken in.
 
i stripped my spur gear the other day and almost stripped the new one. i didnt notice at first when i took it out for a test run, my motor was loose. come to find out my motor mount holes were stripped out as well. well got everything back to normal took my maxx out again and it didnt move. I'm thinkin now what? spur gear was spining, but now its my tranny that stripped now. since break in, I've only had it under full power a few times. I'm still a little on the rich side, temps stay low, i love my sirio......wooohooo
 
I've had both. Only recently had the Sirio .18 give up on me (had it since it was released).

It will be pretty hard to find parts for it since it was basically "replaced" by the Sirio .23 (which I have now). In the meantime before I bought the .23, I did the traxxas exchange with the anemic old pro-.15 that originally came in my generation 1 Maxx (burned up a _long_ time ago).

Unless you completely seal the carb on the 2.5R with black RTV on any and everything that has a plug or screw on it, it's almost impossible for the thing to hold a tune. The carb is made of some crappy composite that is exceptionally prone to leaking and cracking/stripping around the HSN. After breakin and 3 or 4 tanks following that, it was enough. I pulled the trigger on the .23.

Both of the Sirio mills come with what feels to be an aluminum carb. The .18 certainly did twist the plastic sliders (mine look like barber shop poles without the red and white paint), but they haven't broken yet... they're still OEM. I've had to replace 1 rear diff with the .18 in it. But boy was it fun doing the damage.

Bottom line, you'll be very happy with the Sirio .18. Moreso, in my opinion, than the 2.5R. However since the parts are getting harder and harder to find, you'd best start looking for a replacement piston/sleeve now, and keep it tucked away somewhere for the future. I was able to get several gallons through my .18... more than I expected (7 or 8?) before it finally gave up the good fight.

Of course, now that the .23 is in there, I'm expecting some _serious_ damage. (: This thing makes the maxx wheelie over when it hits second gear even with super soft springs on the rear.
 
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X_Gamer7 said:
I really can't stand it when people say stuff that has nothing to do with the thread at hand. I am glad that your engine has a lot of power, good for it. That had nothing to do with the question though. Your post would've been a whole lot better if you said that plus "hey, but out of those two engines, I would definitely prefer (engine) because (yatta yatta)"
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Just suggesting it because it's easy to find parts for when one of the two wears out. I don't need your post critiqing, keep your negative comments to yourself.
 
rbmaxxbasher said:
Just suggesting it because it's easy to find parts for when one of the two wears out. I don't need your post critiqing, keep your negative comments to yourself.
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It still had absolutely nothing to do with the question though. He was trying to choose between a truck with the 2.5 or sirio .18... I didnt see a .21 in there anywhere... :2cents:
 

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