Problems getting LRP engine to run

[Lonsdale]

Hi
I have a .21 lrp nitro engine with r5 glow plug running on 25% byron fuel , i have got the h/s and l/s screws , at factory setting
It starts up fine , but as soon as you blip the throttle it dies , i have tried riching the l/s screw, but it makes no different ,
Im constantly starting it up on the starter box , and it then stalls.

Any advice would be grateful ,