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Sirio .18 VS TRX 2.5

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Maxxbash

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Hi I'm knew to this forum, first I would like to thank eveyone for the great advise I've read here without you knowing you have all helped me a lot, so thank you.

second. I bought my Tmaxx a couple of weeks ago, I bought it used and came with an OS .12cv I love my maxx but I'm dissapointed in the power it has, I thought it would at least be able to peel out in loose dirt but it doesn't, so I am now wanting to up grade either the 2.5 or sirio .18 but I'm not sure how much of a difference I will see from the .12 to either one of the two engines, so i was wondering if any one has experince with the os .12 and with the 2.5 or sirio, I would really hate to spend the money for the up grade and not see that big of an improvement in power and wishing I had stayed with the os, your advise will be greatly appreciated.
 
well first its hard to say, as the OS .12 may be very tired or not well tuned if it can't break loose in dirt. although I've never seen a OS .12 cv run in a maxx, i can say that the trx 2.5 is a very powerful small block, if you can get it to run right. so all variables aside in break-in and tuning and if both mills were brand new...the trx 2.5 will be a huge difference in power between the OS .12 cv. while OS claims a .56 HP, the trx 2.5 has a RCNT dyno proven 1.33HP. the only drawback with the trx 2.5 is it really needs an upgraded cooling head before you can attempt to realy give it a good reliable tune. and as for the sirio .18, you can't go wrong with that mill either, and it has more power all over the powerband (low end, midrange, top end) than the trx 2.5, and without saying eats the OS .12 CV alive still screaming.
 
thanks for the reply, would you know what the hp is on the sirio?
 
well the claimed HP of the sirio tx-18 is 1.9HP...this is hard to say if it realy puts out that much power...altough i can say that sirio's .15 put out 1.57hp when it claims to have 1.7hp, on RCNT's dyno. so even if the sirio .18 doesn't have 1.9 real hp, i can say that when i ran mine with the matching big bore pipe it was a screaming demon of a small block, and may well have a real HP 1.6-1.7hp.
 
I have read that the TRX 2.5 very hard to tune, how is the sirio as far as tunning also, what else would I need to buy in order to upgrade to the sirio? dies the pipe really make that big of a difference? or would I be able to use the pipe I already have, actually I was thinking of going with the dual exhuast, would that work with the sirio?
 
yes my trx 2.5 was hard to tune..due to the fact it was my first nitro engine ever and the fact it is jsut a hard to tune mill. after buying a 30 dollar upgrade cooling head and RTV sealing all possible locations for air leaks on the motor, i was able to keep it at a stable 235-245, and it then became a very fun motor for my t-maxx. but after being dead even in a drag race with another trx 2.5 t-maxx, i wanted more. so in went the sirio .18. the sirio will be a little hard to start/break in the first time due to having a very tight piston sleeve. as for tuning, while it wasn't the easiest motor I've owend to tune, it was better than the trx 2.5 when i first got it. IMO it has a small "sweet spot" and doesn't have alot of room to play with on the needles...although it definatly isnt so bad that you want to throw it into the wall (*ahem* trx 2.5--) yes, the sirio big bore pipe made a great differece, actualy i ran the big bore pipe with the 2.5 before i installed the sirio, and it made a nice difference with the 2.5, and it has a very nice sound, kinda like a crouch rocket. as for what you will need to upgrade to either, I'm assuming you have the older t-maxx? if you do try a search on upgrading to trx 2.5 and you should find out what all you need, i do know traxxas sells slide carb upgrade kits.
 
I have a sirio .18 and Right now I'm tryin to use up the last 1/2 gallon for 10% I have and It seems to scream even on 10% and the stock 2.5 pipe. Soon as I finish off this 1/2 Gallon. I'm gona swap to 20% and a sirio .18 pipe.

Unless I sell the mill and go .21 conversion for a rc limited chassis I'm about to buy
 
Yeah, since this thread is almost 3.5 years old, and I was about to post.
 
Lol, so funny. My momentary onset of idiocy has revived a thread from december 2003. This is my last post to this thread.
 

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