Note: I posted this at LSTCentral, but I'm hoping to get some feedback here as well:

So, a little history on my truck. Earlier this year it met a large puddle, upside down. Sad This caused the engine to seize up and required me to tear it down and clean it up, etc.. Everything looked okay and the engine is still running today.

This weekend I was running with my brother, who also owns an LST and I changed glow-plugs because my truck was running poorly. So, I put in an OS 8, which was the first new plug I found in my box. After I get it in, my truck is popping wheelies in high gear! Needless to say, I'm pleased.

Now, some questions. First off, while my truck can now pop wheelies, it really has lost its top-end. My brother's LST blows mine away on a straight drag. Secondly, my truck really seems to bog down under full throttle. For example, if I slam the throttle from a stop, I'll never hit 2nd gear and I can just feel my truck struggling for more power. However, if I slowly accelerate, it will shift in about 30 feet and take off like a rocket (still not as fast as I expect, based on my brother's truck's performance).

Anyway, does anyone have any suggestions for rectifying the top-speed issue? Any thoughts on what is happening to me at full throttle? For me, it's not a huge issue, except for bragging rights, of course Smile

Thanks!

Sounds like your tuning is off. Wheelies from a lean LSN and bogging from a rich HSN. Give yourself a 1/8 turn lean on the HSN (and a 1/16 turn rich on the LSN) and see if your RPM's come back up.