rb25det soon off after I start while engine is still hot??

[syam]

I just swap rb25det to my r32 skyline ...before rb20det..
my problem is when I started the engine in the morning ( while engine is still cold) my car can start as normal but when I start it's after engine are still hot...my car can start but soon off... I already make my engine timming high ...now about 800rpm.don't know why???
anybody had facing this kind of problem , please help me??
one more if anybody have fuel pump for rb25det engine and want to sell or know where I can get this fuel pump, please let me know.....
thank you.