Tip for slightly quieter exhaust
 

I just fitted a Dynamite exhaust deflector(little silicone hose to deflect the messy stuff) but i noticed it affected the sound quite significantly.

It's alot quieter at idle and whilst not significantly quiter at high rpm, it does seem to take the edge off the noise and sounds less harsh.The sound seems to echo a little less and so doesn't travel as far.(not so important seeing as my nearest neighbour is over a mile away.)

It didn't seem to affect performance at all,in fact this Sirio 27R seems to gain power with each tank but it is still loosening up.Just coming up to 1 gallon but not bad going seeing as i've been running it less than a week.

I have to say this engine is superb,definately the best i've used by a million miles.I was totally fed up with nitro before trying this engine and had sworn to convert everything to brushless but now i'll be keeping one as nitro.This engine is so nice.

Not all big blocks are the same.Before you give up on nitro, give a Sirio a try.

I noticed a slight difference in sound on my T-Maxx when I put the deflector on. Didnt notice any power difference though.
What kind of truck do you have your Sirio in?

In an LST. Been trying some speed runs with it today with 6 tooth larger pinions than stock.Combined with the extra 10,000 rpm of the sirio should hit 60 i reckon if i could get the damn thing to shift into second.

What are you using to measure the speed?

A garmin gecko (little gps unit).A lack of AAAs for the gecko was a slight oversight today hence no results yet.

I'd like to get a reading just to compare when i get my brushless LST running.Still in the build process-custom tranny took up most of this last week and waiting for materials for lower deck.

Well keep us updated.
I will be attempting another top speed on my Maxx as well as soon as I get it put back together. I wont be close to 60mph though like you, maybe 50 if Im lucky.
Have fun!

Yeah you too, i don't know if this thing will hit 60 either.It's just a guess, probably a little optomistic.I guess we'll see.

I use something with three wires to make it more silent..

LOL!

Yeah me too,i still have fun with nitro engines on occasion though.
I don't like the noise(grating) but the feel of a real throttle i enjoy from time to time.Takes me back to my racing days a bit i guess(not RC racing).

I agree brushless is the most ideal solution for RCs available.Otherwise they wouldn't be the primary source of power in my RCs.

For me the most ideal thing would be a combustion engine that was lightweight like a glow engine,produced the torque and power of brushless,didn't need a rebuild every 5 minutes and didn't make the incredibly irritating noise of a glow engine.

Unfortunately,such a device does not exist.I do enjoy the feel of a combustion engine and i guess that's why i still use nitro on occasion.(when i can stand the noise).

What kind of racing did you do?

Single seaters.Nothing major just a few seasons in Formula Fords.
Pretty frantic form of racing though,lots of wheel to wheel stuff and short but aggressive sprint races.Being open wheelers it's easy to lock wheels with each other and end up in the air and leaving the track at whatever speed you were doing:rolleyes: .

I wish i could still do it but a couple of years ago i contracted an illness and became disabled.I still have use of all my limbs and am mentally sharp but i lack the muscle endurance for motorsport or stamina for all the travelling and weeks away.i can still drive a bit though;) .

I was about to move over to rallying before i got ill.I was all set to do a one make series in the UK called the peugeot super cup,had the budget in place and everything ready to go.If i ever get to drive again i'd like to do something like that.

Got me back into RC though,and right now i'm building a truck that's gonna kick some ass next season when i should be up to it,brushless powered of course.
;) .

Hey gustav. Watch the heat on that engine, i've had friends try this and a couple had trouble with heat no matter how they adjusted it untill they removed the tip so be careful.

Thanks crazyjr, the engine itself runs a nice temp (200-220F)and it's fairly consistent with a Nova cooling head.The exhaust itself gets very hot though,i'll compare with and without the tip,thanks.

Glad it's working for you, just thought you needed to know.

Hey Gustav,
Sorry to here about your illness. I use to do alot of autocrossing and road racing with my own personal vehicle and I know what you meen by stamina, racing does take a toll on you.
Never did any rallying, this is the closest I have ever come to it though. The guy that owned that car took me for a ride in a dirt field by my work....it was awsume! Hopefully you'll be able to drive again!
Good luck to ya.
John

Thanks John,

I'm making very good progress in recent months,slow but steady.In fact, i've been putting my mountain bike together this weekend so i can start off with some light excersise.

I used to have an autograss/autocross buggy which i did't compete in,just used to play in the fields with it.I regret selling that now.

What sort of car did you have?When you say road racing was it circuit racing?

That Rally car looks interesting.Only other current cars i can think of with suicide back doors are the new rolls royce and the mazda rx8.

if i do get to race/rally again i'll probably build/run my own car.(nothing too grand).I'd like to do a 4x4 for offroad trials or a rally car for club events.

For no particular reason,here's a pic of one of my dream cars in action:

Hey Gustav,

Carefull on that mountain bike.:eek:

I actually raced a truck believe it or not. It is a 1990 Toyota truck. Standard cab, standard bed. Really light, I had it weighed in at about 2700 lbs. I had all the suspension work done (as much as you can do to a truck anyway) lowered, big anti-sway bars ect. The motor is a fully built supercharged/nitrous oxide nothing left stock (that I can think of) 4 cyl. Yes 4 cylinder. It's putting out an estimated 350hp. I am only running about 10lbs of boost is why the horsepower numbers dont seem bigger for everything I have done. Some of these guys with 4 cylinders and turbo are putting out well over 1000hp! Those are drag cars of course which I also use to do with my truck.
I did not race circuit when I did road racing. It was an old airport strip that they converted into a road course. Pay an entry fee, tell them what you are driving and they would put you in a class. I only did that course twice though.

Yeah that Saturn rally car was pretty interesting. Saturn sold him that car for only $1 and sponsored him for a season or two?
Saturn was actually the first coupe (modern coupe anyway) to come out with suicide doors back in 1999. They dont sell Saturns in the UK do they?

Your dream car.....Looks like an early to mid eightys quattro?
John

That truck of yours sounds really cool,i bet that was heaps of fun.
I love the sound of a supercharger aswell.There's something very satisfying in building something fast out of something that wasn't intended to be.Kind of like what i like to do with solid axle RCs.

Yeah,the 80s was probably the golden age for rallying.Huge crowds in those days.I think that car may be an early Group B or maybe earlier group 4.Audi were the first to pull the plug on group B after a series of accidents involving spectators,the class was banned shortly after.

Speaking of big power from little engines,in the 80s F1 teams were achieving 1500 bhp from 1.5 litre turbo 4 pots(imagine the lag on those!).Rumour has it that the BMW blocks in the Brabhams came from old road cars and some say that the engineers used to pee on them and leave them outside(sounds unlikely but who knows).

soo...?????
 

....so this means that there is a solution to very high rpm noise is lower.....and can this solution be solved to all nitro cars?????? if possible for a nitro mt-2 then please notify me... thank you
:027:

Only made a small differnce,just kinda took the shrillness/high frequency down a bit,it was on a loud pipe.i don't think there'll be a way to solve the high noise levels,they need the pipe to resonate as i understand.I don't have any neighbours for a good 1/2 mile or so,so i used to keep the nitro for the crappy weather, but i gave up on nitro stuff in the end when it annoyed me for the last time.