Does it, i have a t15. this is the new head? will it bring temp down?

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Why are you worried about the engine temp?
Most car engines I've seen are over cooled in the first place, causing them to run way too cool. Those that are not, are just right.

cause temo is why i think its shutting off

Describe your problem with a little more detail. Between me, Fuelman and a couple other engine folks on the boards, we may be able to ehlp you without you re3sorting to buying a new head.

the heads bought but the scenario is this: 7 min in it shuts off, ive tried tuning but still the richer i go it last longer but eventually shuts off

If I was a gambling man, I would bet that the piston and sleeve pinch has already been lost. As the engine throughly heats up and the sleeve expands to design fit, the diameter of the sleeve is now bigger than the piston because the piston has worn down. If an ABC engine has lost its cold pinch at top dead center (no plug installed) then the piston has worn to fit a cold sleeve and will do exactly what Mchwind describes. What causes this??? Running them too cool to begin with.

Buying a bigger head will only aggrevate the problem, it may work for a short while because it is preventing the engine from achieving design temps, to artifically create an interference fit (pinch) between the piston and sleeeve. This will in fact further accelerate the wear of the piston and you will need to buy an even bigger head,.....and so on.

If I am correct, you have probably lost most if not all the pinch in your engine when the plug is out and it is cold. If that is the case, buying a new piston and sleeve is the only solution. Then you need to break it in correctly, (the hot method, not the ideling method) and not run the bigger head and let the thing get to design temps.

interesting, but this motor is practically new, i got it during aug? can this still happen, and if anything ive been running it leaner i think not cooler, but let me know

Some engines don't get enough cooling and must be run a bit rich to prevent overheating.

I upgraded the cooling head on one of my motors and was able to run similar temps but with more performance.

remove the plug, spin the engine over by the flywheel with a finger. If it rotates very freely without the piston actually sticking when it gets near the top of the stroke, it is shot.
If you still have a nice tight pinch, then I am wrong.

It only takes a couple tanks of fuel running them too cold to ruin the pinch. Once the pinch is gone or nearly gone, nothing can be done except replace it.

First do you know what temperatures you have? All so there are other things that will make an engine heat up like air leaks! I have yet had an engine that I needed a different cooling head to keep temperatures with in range. Before I jump to conclusions one I would buy a Temp Gun and two I would try sealing the engine.

The temp gun is on its way to my house, and as for the piston sticking, i will try that this afternoon, and let you know if it sticks