Another reason why you might notice the difference between the Futaba 9402 and the KO2143 is that they are from 2 different manufacturers.
They might have different ways of measuring their speed and torque.
There's always going to be some sort of tolerance between reported specs and the actual product.
That's why when it comes down to a .05 second difference, I feel like there is no real advantage.

By hearing the sound of the engine makes?:sneaky: But seriously, that's how I do it.

You could do a pinch test on the fuel tubing to the carb inlet. Choose a location closest to the carb inlet and pinch. If the engine will die off in 2 to 3 seconds, then it's OK. If it dies out very fast, then it's lean. If it takes forever for the engine to cut off, then your low end is too rich.

What I do when I tune engine is this. I rest all needles (HSN, MSN and LSN). HSN to 6 full turns out, MSN screw flat to the carb body (or 2.5 full turns out from close if it's a NOva carb) and about 4 full turns out on the LSN. The idle needle, I open it up a little so that the engine does not die of. I start the engine and blip it to get the engine going. I'll lean the LSN so that I can get a constant idle and at the same time backing out on the idle needle so that at neutral, the slide carb opening is about 1 mm. When you lean the LSN to a point when the idle RPM starts to go up, richen it about 1/4 turn out. The idle should be steady.

Then start to lean the HSN till the engine easily reaches high RPM. Once you got that, richen it 1/4 of a turn.

The above LSN and HSN tunings are just ball park estimations to get you nearer to optimum settings. You need to put the car on the track and tune the needles.

Some pointers;

If you rev and blip the engine to WOT quickly and the engine bogs down as if there isn't enough fuel going in, then the HSN is lean. Richen it.

If after coming to the pits the engine idle goes higher and higher, then your LSN is lean. Richen it.

In any case, check the temp of the engine from time to time to see if it's running OK. Use your saliva on the heatsink if you do not have any temp probe.

If your engine is overheating, your engine will protest and will not sound right. The best way to know if your engine is overheating or not is when you cut off your engine, you can easily start it back up without priming the carb and the engine can idle very smoothly.

I run a .15 RDLogic pipe with a Novarossi inline pipe header. That gives me about 88 mm pipe length. Very nice high end pipe. Combined with a 0.7 mm Centax clutch gap, modded flyweights and 1.1 mm on the clutch nut setting, it gives very agressive power to the wheels. For smaller tracks where smooth throttling is required, 0.4 mm clutch gap is nice.

For Nova engines, I would generally err with the NovaMega TP06 inline pipes or the Novarossi 52606 EFRA or the 52607 Outlaw inline pipes. Both NovaMega and Novarossi pipes are similar. You get spot on tuning and about the best compromise on top and bottom end power with these pipes. For Sirio engines, I think it would be best to get the Sirio inline pipes.

Check to see that there are no leaks.

From what I read, the body is pretty neutral.

Thanks InitialD.
I'll put an order in for a couple of them.
I'll let you guys know how I like it.

Re: Mazda6
 

Nice paint job, I would hate to bang that up. Did you paint it yourself:sneaky:

I have a Nova Max engine that has had about 20 tanks through it now, and i run a 20min race on the week end and after about 15 mins and a second fuel stop my engine sounded different when accelarating could this be due to overheating? i run the last 5mins and finshed, was this a good idea? have i done any damage?

Quoted from Per-Ola's race report on mytsn;

"I used a prototype body from Serpent a Volvo S60 (well, you better drive a Volvo when you are in the home city of the real Volvo factory located just some hundreds of meters away from the RC track, right….). The Volvo body was working very well in the high-speed parts of the track, the whole car felt very easy to drive and I could easily drive the 45 minutes final without and driving errors or anything."

http://pic9.picturetrail.com/VOL292/...8/50259834.jpg

Thanks D.
Sounds good to me.
Now I need to stock up on some orange paint.

were do you get those black serpent bags from?

What do you mean your engine sounded different? As long as your engine can idle and accelerate with same power, that's very unlikely that the engine is overheated.

Anyway, I had an instance that my engine sounded different too during the last race. It sounded as if the engine was hollow and was making some sort of vibration noise from within the engine.

Went home and took the engine apart and inspected the internals. Found out that the middle bearing was loose and gritty. Changed it and now it sound like a champ again. That could be your problem...

There is the large one (1980) and a smaller one (1981).

engine
 

no thats it it lost all its punch at first i thought i had siezed the clutch or the diff was loose but all of that was ok?

Oh i thought the black 1 was like the 3 draw mugen bags, do serpent make a bag lke that?

Re: engine
 

Perhaps you're right then that the engine overheated... Did you open up the engine to check the internals and check if the compression is still there?

Not that I'm aware of.