i have a os 18 tz and have ran 5 tanks the first tank i ran it off the ground but not much over idle and the rest of the tanks i ran on the track and the temps stay around 150, so how many tanks should i run before i lean it out, i have leaned the high end out a little so it would stay running. what do you guys suggest, also i realize now i should have ran the first tank on the ground but thats already done. i need the engine ready to race by the weekend.

keep running tanks thru it and lean a little each time, you usually need about 10 tanks for an engine to wake up, also make sure that the piston is on the bottom of the stroke (engine) when you let it cool between tanks, you should have the engine running at 200 but not over 230 during the first 10 tanks.

150 is WAYYYYYYYY too cool. On brerak in you need to be around 200. If not it will not break in properly and can cause damage to the engine.

to get the temps up do i need to turn the low speed needle in some or just the high speed needle and after the 10 tanks will it be ready for race tunning, also i have the high speed neeedle set and just under 2 turns what is the most i should go in with it.

turning in is leaning it out. The more lean you have it the hotter it will run. If you cant get the temps up then take a wet paper towel and wrap it around the head and run it. This will help. 10 tanks if broke in properly is plenty for race ready but right now sounds like the first 5 will be useless because it did not get up to operating temps. If you dont let it warm up to 200 during break in the pinch will be too tight adn you can break a connecting rod on higher rpm's.

do lean out the high end needle or do i need to lean out the mixture needle (low end)

You do the high end first then the low end. Anytime you change the high end it will change the low end slightly so you have to readjust slightly.

what temp range is good for this motor after it's broke in tonight i hit 250 with it is that ok.

250 is great. 270 is on the high end and 230 is more on the low end.