Rudolph Hart

Hey you lot! does anyone know off hand what the flashpoint of castrol r is? and the average temp of a hot bbq plate? going over to the neighbours place for a bbq and thought i might try some i borrowed off a mate last week.Don't ask me what i tried this time last year but it was a few weeks before we were back on speaking terms.He's a brave fella

johnfly

about 540 F on the castor. I don't think I want to know any more !!

hsukaria

Lifer,
I have never compared stock to Turboheader mufflers back to back. The seller claims 200-300 rpm increase. I primarily use them to squeeze the muffler inside warbird cowls and they make a deeper/throatier sound that is more scale authentic.

w8ye

My Feedback: (16)

I have around a half dozen Turbo headers and they perform as the manufacturer claims.

SrTelemaster150

Does that apply to big block (150/180) singles?

1320Fastback

First time Saito owner here. I have a H9 81" cub with a Saito .62GK and a 13x6 APC prop.

Motor was purchased new but broken in by a reputable seller and has been nothing but perfect so far.

My question is about smoke output. Having a bunch of 2stroke glow I am quite familiar smoke trail and general tuning.
Don't get me wrong this engine runs perfect I am just wondering a few things.

Flying at midrange throttle which a big Cub likes there is a very heavy dense smoke trail, upon sudden full throttle the motor crisply accelerates without bogging or sputtering but flying at full throttle their is very little smoke output. If flying left to right by you you can not see smoke but during a turn when the plane is End On view you can see a little smoke output.
Is this Lean on top end?
Should I richer the top end and lean the bottom slightly?

I am using Powermasters 20/20 fuel.

Thanks

blw

My Feedback: (3)

You are seeing the transition point between the low speed and high speed needle valves at 80% or so throttle. Your low speed is set richer.

FNQFlyer and rc lifer, you both have a very respectable collection on nice engines.

SrTelemaster150

2-stroke engines, be they glow or gas, waste about 30% of the fuel compared to a similar output 4-stroke engine.

A lot of that "smoke" you see @ WOT W/a 2 stroke is unburned fuel.

1320Fastback

Yes that I get. Was wondering if the disappearance of the smoke for the most part is too lean.
At mid throttle is is 5x thicker.

FNQFLYER

I personally like so see a smoke trail. Means that oil is going through the engine and that is good. My Ys's operate well that way and I can see where they (the models) are going in the climb (in duration) and I also know when the engine has cut (no noise & no smoke)

SrTelemaster150

Sounds to me like you are too rich on the LSN. As mentioned, the LSN affects mixture up to about 80% of WOT.

1320Fastback

Ok, kinda what I was concluding also but wanted the experts opinion

The few 4strokes I've seen at the field all seem to leave a trail at all throttle settings and haven't made it out there in a while to pick their brains yet.

blw

My Feedback: (3)

Saitos are different that way. They tend to leave less smoke when tuned correctly in most cases. A well tuned low speed will turn your nicely running Saito into a Swiss watch. When you get the low speed tuned your engine begins sipping fuel, has more power from idle to wide open, and idles low enough in some cases where you can barely hear it on final approach. The last thing you should do is fly the engine around and listen to your turning effort when you think you have it set. Listen for sagging and transition. See if it will glide in on a long approach at idle and do a go around. Will it handle a long vertical climb? Tuning is a trade off between getting it right on the bench and then being right in the air, imo. It is possible to tune a Saito and then leave the needles alone for a year or two after it is completely broken in.

SrTelemaster150

When tuned properly for transition to WOT, you should see a puff of smoke (but not excessive) then the smoke will thin out considerably.

I run CDI so the smoke is a lot less W/the far leaner settings, especially @ WOT, but still there @ part throttle & transition.

FNQFLYER

Apart from competitions, I am a set and forget man (at least leave it alone) until change something, like a prop, fuel (new bottle or different mix) or plug. I then check the full throttle revs with a tachometer and as long as the +/- 10% is achieved I go flying. This is about relaxing / having fun after all

Rudolph Hart

Amen

FNQFLYER

So you are still with us Old Fart. Trust Xmas was good to you and the start of the new year not to severe. Santa didn't leave any Saitos behind after his visit to us HOWEVER there is an amount of surplus cash around that just might be converted into an FG11. The new year is going to be a busy one, getting ready for Canowindra at Easter the Air Races in March and our own club comps in June and later in the year plus continuing with the rehab. Got to fly a Radian last week lasted about 5 minutes on the first flight stretching it to 15 minutes by the last. Concentration and stamina not up to standard yet but we are working on it. At least I am flying again even if I need lots of ground crew to help. I'll be checking out bearing supplies for bits for the 65 and 50 in the new year and running the crap out of all my engines once we settle and the workshop is set up.
To all I hope the new year brings you what you seek and want and stay safe guys

FNQFLYER

On the LSN tuning thing. When setting up a Saito for Texaco (fuel allocation / burn event) the engine is set up to run at a max of approx 5K RPM with climb ( 4.5 pound model) at approx 4,500rpm. This is done by opening up the LSN and closing down the HSN until the desired transition and operating RPM is achieved. We use larger props (on the 65, 15x8, 16x6, 14x8) of various designs (but not wooden) and rely on the prop inertia to keep the engine turning at such low RPM while still delivering the thrust needed to et the a/c as high as possible with the fuel allocated. An interesting exersise.

blw

My Feedback: (3)

Yes, very interesting. Do you just learn to guess at 4500 rpm in the climb?

blw

My Feedback: (3)

W1nd6urfa is now club member # 814.

FNQFLYER

blw if needs be I use an audio tachometer, usually held by my mate / observer/timer or the CD. However in reality the 4,500rpm is set on the ground (using u beaut inputs from my "magic JR 9X radio or 9303 which has normal throttle on the flap drum switch and slave throttlle is the normal throttle control "lever". The desired rpm is set on the ground but the take of is controlled through the slave throttle so I can vary rpm in the take of phase then switch over to fixed throttle for the climb and once that is settled speed / rpm is controlled by the drum switch setting or change in climb angle. Simple really once you get a "computer nerd" to set up the mix program and you trust yourself to "manage the climb".

FNQFLYER

blw, 4,500rpm is nominal and is adjusted according to needs and a/c type and weight

Rudolph Hart

Yes it does.I have an fa220 inverted in a 72" percival mew gull.The stock muffler is very bulky and heavy compared to the turboheader one and i picked up about 160 rpm without even trying,plus it sounds better now.And that only took me ten minutes to do.

Rudolph Hart

Yes fnq i am,not sure about the neighbour tho.You are right about managing those climbs,saw a guy fall flat on his fanny doing that.

Rudolph Hart

1320 i wish i could have written an answer like that