Nick@DevXT

Hey guys, just got into nitro rc cars, my brother gave me his old one and by the looks of it, tore the tuning up. I've just got a few general questions so I avoid breaking something.

Car: RC Lightning STR (2-speed, stock .16)

Here's the questions:

1. What type of fuel should I use? Would 33% be too much for the engine?
2. What are the max RPMs for the engine and how can I tell if I'm running too high?
3. What is the optimal running temperature for this specific engine?
4. Which parts do I have to tune to get the engine running at it's optimal performance?


Any help would be appreciated guys, my brother's rubbing his new car in my face and I do wanna race him ...Oh, and not on foot mind you.

ehroof

1. 20% is best
2. if tuned correctly rpm's do not matter as long as it is running on the ground, not maxed out in the air
3. 230-270 degrees
4. you tune the high and low needles on the carburator, check the nitro engine and troubleshooting sticky

Nick@DevXT

Well thanks, I was also noticing with the engine running, the exhaust seems to sputter alot of excess fuel which seems slightly sludged, is this normal for redcat cars? My brother's car doesn't seem to do this. I switched to 33% fuel and it seems to do it less, but I'm still working on the engine tuning. Also, is there a method of checking the engine temp. without a thermometer? I don't exactly have one handy. My brother said to tap the top of the engine with a spit-doused finger, if the spit sizzles and evaporates, it's running too hot, however this method doesn't seem effective as it always seems to run too hot no matter how I tune it, even to factory default.

zack221

The reason it spits gas out is b/c it is running rich.

zack221

Here is how to tune it.

lsn-ccw richens and cw leans
hsn-cw leans and ccw richens
idle-cw opens and ccw closes

Set air gap of throttle 1.5 mm,(idle screw), HSN Cw til it bottoms out then 3 1/2 turn CCW. LSN Flush with the throttle housing + 1 turn cw. Try to start, will be runnin really rich, if it starts. Turn down idle speed, then adjust HSN cw til you have good acceleration to idle. if your idle speed rises, turn it down. May have to do a couple times. Last adjustment LSN, turn cw slowly til idle speed starts to rise. when it rises you're running lean, turn it CCW till idle speed just drops. Blip the throttle you should be acceleration ok with some smoke coming from the muffler.Lean the HSN 1/8 turn CW till your satisfied.

ehroof

if it evaporates in less than 5 seconds its too hot. it is normal for any nitro so spit out a little oil if it is idleing for a long time. you may need to lean the needle a little.

Nick@DevXT

Thanks for the help guys, engine runs very well (though haven't adjusted the hsn so it gets optimal performance)

However, I was wondering if it's usual for these cars to grind their transmissions? This car's gone through 2 44t gears (1st gear) so far, I was wondering if it's possibly due to the engine placement on the car. I tried closing the gap a little bit to avoid grinding but now the car struggles to hit 2nd and dies often when the gas is punched. I know this is not due to the engine settings because it only happened after I tightened the transmission.

ehroof

you need to put a piece of paper between the spur(plastic gear) and the clutch bell and tighten the engine and remove the paper. looseleaf looks fine, also replace the clutch bell, this will help you out: http://www.freeforums.in/phpbb/viewt...montmotorsport i havent stripped a gear since i changed the clutch bell

Cas_NitroGT

lmao well well my good ole older brother is on the post's... well welcome to the forums nick... these guys will deff help you out... but I tried tellin you... don't tune your nitro with no wheels on the ground. you need to have pressure agenst the tranny to get it tuned right... and plus thats how you grindin your 1st gear smart one. lol belive me here in a while you'll have the car fixed up and runnin great before you know it....

Nick@DevXT

Okay guys, car's running great but cutting out on the high end, which I think I can assume that's because it's running rich. Still haven't tuned the HSN, and it dies when I give it alot of gas.

Nick@DevXT

lol got a big problem guys...I had the car running perfect...Until I hit a car tire head-on at about 30-40mph....I now need a whole new front suspension, new body clips, and a new muffler....Cas might post a pic of it, don't laugh, I floored it too hard and lost control :\

123michael

yes i would like to see a pic bro..... lol