Schumacher XTR .21 Help Needed

Have you broken in the engine? The blueish white smoke is a good thing. You need some to know that it is lubricating... I dont know how it is running, since you didnt state how it is running... do a search on tuning and see what you come up with... There have been many articles about it.

What engine is in it? Is it the TT Pro21R?

Should be...

Should be but others have changed it out and just transfered the drill start to the pull motor.

I bought it used. It is the Pro.21, what is the difference between tt vs pro? I am not sure how to tune? Any suggestions.

TT is just short for Thunder Tiger.

If I were you, I would retune that Pro21R engine. Stock settings from the factory are 2 1/2 turns from closed on the HSN and 1/2 turn out from flush on the LSN.

As you run the car to warm it up, make note of the smoke, there should be a lot because it's running rich. After it's warm, turn the HSN 1/4 turn in the clockwise direction (leaner). Make a few runs back and forth. Adjust the needle 1/4 of a turn at a time till you get the performance you like. Keep track of the smoke. If there is little to no smoke, it's running a little lean. This is where the temps come in to play.

If you have a temp gauge, this engine likes to stay around 230-255 degrees. I ran mine consistantly at around 235-238 degrees. Any leaner than that and she started to complain at WOT. If you don't have a temp gauge, get one but until you do, utilize the spit test.

Spit on the cooling head. If it sizzles off right away, you're too hot. Richen it up 1/4 turn at a time. If it sits there forever, you're too rich, lean her out 1/4 turn at a time till you get to the point where the saliva sits there for about 3-5 secs before boiling away.

To tune your low end do the pinch test. Pinch the fel line about 2 inches from the carb inlet. If it dies right away, it's too lean. Richen it 1/8 of a turn. If it runs for over 5 secs, you're too rich, lean it out 1/8 of a turn. What you are looking for is about 3-5 secs before it dies.

Once you reach that goal, fuel her up and warm up the engine to operating temp. Check the hole shot. If it dies right away or gurgles then clears it's throat, it's too rich. If it dies at WOT or during a high speed pass, the HSN is too lean. If it dies after a highspeed pass (while the rpm's are coming down) the HSN is too rich, lean her out.

Remember, on the HSN, you make adjustments 1/4 turn at a time. On the LSN, 1/8 turn at a time. Make sure your carb opening at idle is about the thickness of a credit card.

When I still had my Fusion21, my carb settings were about 1 3/4 turns out from closed on the high and flush on the LSN. Also remember, your settings will vary from day to day because of temp variances and humidity. Also, my Pro21 liked to run on OS #8 plugs. I tried A3 plugs before but got some serious detonation.

Good luck with your car. It's fast. Clean the bearings in your hub carriers. The stock bearings tend to dissintegrate when not cleaned and lubed. Also, your shift points cannot be changed so don't worry about that. The 3 speed is not adjustable. If you want top end or high acceleration, there are pinions for that. Click HERE for the USA distributer.

Thanks for all that information. I will try those suggestions. Apparently this car must have sat for a while, but she did fire right up once I made sure their were not air leaks new plug. I did notice when I was letting it warm up, it was spitting some fuel from the exhaust so I assume it was running to rich.. It is a fast little truck, much different from my RS4 electric..Where in NY by the way, I grew up in Bayside. Tks again!