T rex mods for extended WOT

[4stroker]

i would like to here from experienced builders/porters on what they would do to a t rex motor to make it last in extended WOT applications, like Oval track speedway or desert racing.

 

it seems this motor runs extremely hot and can not handle max rpm for very long.

 

the specs on the particular motor im talking about are:

 

7mil stroker, 72mm bore trex. it has rossier engineering stamped all over it so im guessing it was ported by them

 

v force 2 reeds, 39mm keihin carbs. 178 main jets, eek needles on 2nd clip from the top. 185psi compression.

 

how much bore clearance should we run on this motor

 

also the window on the bottom of the pistons covers half of the outside two intake ports, should we open the skirt up to unblock this

 

also what sort of ignition curve should we run

 

any help greatly appreciated

[bansheeseat$$]

Couple of things #1 take some compression out of it.The more there is the hotter it will run.#2 Jetting,Make sure the jetting is good,Even a little rich it will help keep the cylinders cooler.You may lose some performance but it will help keep it from melting itself down.As for the clearance,I would probably set it up at .006 thousandths.The tighter the clearance the more friction it will have and as it gets hot the less clearance you will have causing more friction.

There's a few for you,Hope that helps ya.