Sirio .18 on my RS4 3

[.21Rc10GT]

Hey...

Another build thread for me.

I got an RS4 3 Evo for Christmas, and it has been fun, but due to the gas tank primer leaking and feeding the engine lots of air bubbles and making it overheat, the engine is pretty much toast. I am going to be upgrading to the Sirio .18 older t-maxx version with the rear exhaust. I ordered the HD diff gears and drive cups all around, and was wondering if there is anything else i can do to make this handle the power of the sirio. I have a carbon fiber upper deck and shock towers. I bought a primerless tank (hopefully will solve the damned air leak problem, i am replacing the fuel lines as well), i got the lightweight flywheel and MIP clutch, along with the red (top speed) gear set for the clutchbell. I also have the Motor Saver air filter. Any suggestions would be nice. Thanks.

 

[AC48]

How about a Collari .32?

I got an RS4 3 18SS in december and have got two tanks through it, stupid snow is keeping me from finishing the breakin.

Here are the things that came in the 18SS to handle the .18:

HD Diff geats
HD Ring/pinion gears
HD Drive cups
Red CB gears
Manual called for a stiffer spring in the 2-speed then was in it from the factory.
Also had a fiberglass brake disc

Other than that, get some good tires!

 

[.21Rc10GT]

Well, i have pretty much all of that... Another question i have is what pipe should i use with this? I have the stock plastic pipe, and it just sounds weenie compared to all of my friends' rs4s... (One is running a c-vec and the other has a THS). Any suggestions?

 

[AC48]

The stock pipe is kinda crappy, makes the engine sound suffacated, I ran a THS on my old RS4 and plan to on the 18SS when I get some extra cash. I really liked the THS, opened up the bottom end quite a bit, and little gain on the top end too.

 

[markallen]

Why would you run a Sirio .18?If you already own it sure but I wouldn't buy one cause the OS 18 TZ will smoke it..Even the OS 18 CVR beat it in the RCCA .18 shootout.

Mark

 

[.21Rc10GT]

I just like the specs of it. I dont see how the CVR smokes the Sirio when the Sirio makes more HP, torque, and spins about 5,000 more RPMS. And the TZ doesn't come in Pull start, which i want. I was originally going to run the Epic .18, because it seemed like a monster as well, but i stand by the sirio name. I have owned OS before, and i really didnt like it. Maybe i just got a lemon, but it shut me out of their business.

 

[markallen]

Specs that manufacturers put on their own engines don't mean crap..It was in the December issue of RCCA.I run a CVR and it is almost as fast as the TZ on topend.And the TZ is awesome on the top..Don't get me wrong Sirio does make a great engine too.I really liked the Sirio .12 I had ..It was super fast..

 

[.21Rc10GT]

Another problem is, this is pretty much my choice... Myself and three other friends are upgrading to the .18s, and the choices we made were either the 18ss, the sirio .18, or the epic .18... I chose the sirio, just because i think it is a better engine. We are kinda making our own club racing thing between ourselves, so we dont want too much of an advantage over eachother.

 

[.21Rc10GT]

Well, i found a TZ in pull start version... http://www2.towerhobbies.com/cgi-bin/wti0001p?&I=LXHLV9&P=7

Would this be a better choice than the Sirio or Epic??? I might try it... I really didnt like my old OS .15 cvrx... It just seemed to be a gutless wonder and always kept getting out of tune... If the TZ is faster, and more powerful, i may try it.

 

[AC48]

.21, I would really suggest the .18 TZ. I thought you already had the Sirio. Mark is right, the CVR and Sirio were both dynoed and the CVR was the most powerful.

I believe they dynoed the TZ and it made over 2 hp, I think mark has one in his TC3, I saw a vid of it and it FLIES.

 

[.21Rc10GT]

I think i might opt for the TZ then... Maybe someone else can convince me... ;-)

 

[Rotorxhead7]

hell yeh the TZ is a really really fast engine to put in a 10th scale rc car!!!

i have the tz in my jato and i can hardly keep in check on the track!!!

i was gonna go TZ in my RS4 but i think I'm gonna opt for the cv-rx because is half the price!!!!

TZ= $200
CV-RX= $100

 

[NSantana]

Hi there,


Rotorx...It's a good decision in opting towards the 18CV-R rather than the Tz for the Nitro3 IMO. Remember, all the power's only good if you can use it. I have the 18CV-R in my Nitro3 and with the right gearing, tuning, and pipe, it has PLENTY of punch. I honestly think the TM & TZ models are better suited on another car/truck and because of the "limited" suspension adjustments, it'll probably be a job just trying to keep the wheels on the ground and not have to buy wheels & diff gears after every day or so of use. In any case guys, it's your money....if you like it, get it. Have fun

 

[Revo Rancher]

21, did you get the optional HPI race tank?

Also, watch that steering servo. The stock ones are real weak, even for a road car.

As far as the mill, they are all good choices. Go with your gut feelings about it. It's your car and mill.

As far as a pipe, unless you WANT noise, I like the Vantage series of TC pipes. Nice tune out of them. I rarely have to make carb adjustments.

 

[NSantana]

i second revo rancher,


The vangtage pipe is awesome....great tune, great sound, and its super light...helps out with the weight distro in the nitro3...


And on the servo topic,..the stock ones are ok for bashing (and bashing ONLY) not too powerfull and not too responsive..but then again, they're stock. I'd say to keep the one on steering as a spare throttle servo and get something like the fut s3305 for the steering (plenty of power with a .2 sec response time...good quality servo for the price). Just remember, if you go for the high torque servo..you might want to look into some good alum. steering cranks (wpr or hotbodies to name a few)

 

[jpsonoma]

I thought I would chime in on this subject. I have two RS4 3's. One has an OS .18 CVr, and the other has the .18 TZ. For the money you can't beat the CVr. It's cheap, runs perfect, and has tons of power. Don't get me wrong the TZ is an absolute monster, but I'll even admit it's way too much for my RS4 3.
Plus with the TZ being a rear exhaust it can sometimes contact the rear wheel. It's hard to say witch one is "faster" Because the car with the CVR in it, I converted to a rally car. So theres no 2 speed in it, and I have it geared for low end. I'm actually considering downsizing the TZ to something smaller, just because it's to hard to keep under control. My vote would go to the OS .18 CVr, plus its side exhaust. Hope this helps your decision, and feel free to ask more questions.

 

[markallen]

I am running a OS .18 TZ at the moment in my NTC3 and I have raced another NTC3 with a OS .18 CVR many times.All I can say is the TZ is faster.It really pulls the CVR on topend.I plan on getting a video this weekend..

Mark

 

[NSantana]

I am running a OS .18 TZ at the moment in my NTC3 and I have raced another NTC3 with a OS .18 CVR many times.All I can say is the TZ is faster.It really pulls the CVR on topend.I plan on getting a video this weekend..

Mark

____ ____


Agreed,


The Tz is hands down the faster of the two and with the pillow ball suspension of the tc3, i have no doubt your car can handle it better...but for the nitro3, as just confirmed in the last post, it's borderline overkill....drag-racing = suuuure. keeping on a track w/o foams and a good servo/steering system upgrade = probably not happening.

 

[bigsouljaslim13]

I have a rs4 3 18ss if i put that 18tz on it would make .5 hp more than the 1.5 hpi says the 18ss puts out ? Wow that must be buttloads of power becauses\ it can be hard to control even with the 18ss at times..

 

[NSantana]

Yep...


Another thing about the makers of these engine....

HPI tends to overstate the performance of their mills. OS, on the other had, almost ALWAYS understate the performance of their engines. Here's an example:

HPI T-15 is claimed to have 1.2 HP..Yet compared to a used OS 15CVR its slower and the makers each claim to have 1.2HP on their mills.