I'm thinking of picking up one of these mills... Is there a pullstart I can use on this engine? Likes, dis-likes about this mill?
Thanks....
Thanks....
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Sirio TX .18 question.... ??????
- Thread starter ImBroken
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well I just put one in on myne and WOW what a diffrence any way iam using the traxxas 2.5 pullstart because they have those backplates on the sirio and it just screws right in. Anyway I like it it has a nice curved grip on it so it fits snug on it when you are breaking it in it has LOTS of compression ask MC he knows what Iam talking about. He did a couple of pulls on it. Other than that its a awsome engine lots of wheelis an lots of potential power. What I mean by that is I have it really rich runnig blue thunder thru it and still have the carb restrictor in it and its kinda to much power for me. So are you converting to 2.5 to sirio or .15 to sirio?
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I'll be changing from an OS .15CVX Hyper to the Sirio TX .18.
So, the Traxxas 2.5 pullstart will fit on the Sirio? DO I have to change the crank or backplate?
I'm still debating on just doing a .21 conv. but I'd almost just rather buy the new Savage kit... Choices....
So, will I see a large improvement with the Sirio, or am I just being optimistic....
So, the Traxxas 2.5 pullstart will fit on the Sirio? DO I have to change the crank or backplate?
I'm still debating on just doing a .21 conv. but I'd almost just rather buy the new Savage kit... Choices....
So, will I see a large improvement with the Sirio, or am I just being optimistic....
LARGE improvment with the sirio. The 2.5 pullstart will fit right in but I think you need a one way bearing the 2.5 one that will work. The backplate is ment for the TRX 2.5 EZ start so the pullstart will fit right on. A .21 conversion cost alot of money you have to buy the kit the engine gears and some .21's have only 8 ports the sirio .18 has 8 ports so it just really no diffrent.
kwong2001
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Um, the amount of ports doesn't necessarily dictate how powerfule the engine is....
SuperMaxx97
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speaking of ports. what do they do and what are they?
bryan
bryan
GilBeQuick
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The ports of the engine you hear about are grooves in the sleeve (cylinder) of the engine, and in the case. You know how you can look through the hole that your exhaust comes out of? Well, that's the exhaust port. The other ports in the engine are there to maximize the efficiency and power of the engine, allowing more air and fuel to pass through. The more air and fuel your engine can process, the more power your mill will make.
The real science in it all is exactly how the engine needs to be ported to make more power, with fuel economy sometimes a factor in mid-lower grade engines. You can't just crack open your case and bevel out holes in it and make more power. There are precise places of size, shape, angle and depth that are taken into cosideration.
Check out this site and you'll see pictures of what ports are all about: http://www.nitrorc.com/mods/engines/trx15mod.html
I did the mods to one of my old TRX .15 Pros and man, what a difference. Night and day. The article mentions that Traxxas engines are less expensive because they skip some secondary machining processes and man are they right on the money. Anyway, hope this helps. Don't be scared to take out your sleeve and see what's going on inside, it's extremely easy to do and can really show you what's going on in there.
-Bryan
The real science in it all is exactly how the engine needs to be ported to make more power, with fuel economy sometimes a factor in mid-lower grade engines. You can't just crack open your case and bevel out holes in it and make more power. There are precise places of size, shape, angle and depth that are taken into cosideration.
Check out this site and you'll see pictures of what ports are all about: http://www.nitrorc.com/mods/engines/trx15mod.html
I did the mods to one of my old TRX .15 Pros and man, what a difference. Night and day. The article mentions that Traxxas engines are less expensive because they skip some secondary machining processes and man are they right on the money. Anyway, hope this helps. Don't be scared to take out your sleeve and see what's going on inside, it's extremely easy to do and can really show you what's going on in there.
-Bryan
StrechM
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I've done the sirio .18 conversion and it sreams for a small block once dialed in. Runs best after you run a gallon or so through it, try 30% and one extra thin shim. The real power shows up with the recomeded pipe. There is one in my gallery. I've alot more mods after those pics and I'll update them soon.
Dislikes, does not produce the powerband of alot of the bigblocks.
Dislikes, does not produce the powerband of alot of the bigblocks.
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GilBeQuick
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that's because it's not a big block. it's a very powerfull small block. but the sirio 18 will put some of the sport model big blocks to shame. hell, at times it can be hard enough to keep the sirio in check, i'd love to feel the difference a .26 would make....
SuperMaxx97
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so about the ports could i have somebody make more ports or what?
bryan
bryan
GilBeQuick
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dont get all port crazy or anything. even if you could add one more port, you wouldn't be able to see a power gain by just bashing around. it'd be more of a time trial on the track than anything.
SuperMaxx97
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o i c, oh well. my motor has more than enought power.
bryan
bryan
You mentioned that you put one extra thin shim on? We race T-Maxx with an 8 port Sirio 18; we won regional with it, lots of power. My son races it and he say it hard to keep the wheels on the ground we use O'Donnell 25%, so what did the extra shim do for you? We also race 1/8 scale he took 8th place in the A-main at same race, both mains 30 min Maxx came in @ 204 degrees, 1/8 scale ran out of fuel he was in 5th place with 1½ min to go, by the time we got back on track we finished 8th.
So tell me about the extra shim?
So tell me about the extra shim?
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