450 motor help!!

[mudrunner35]

if i put a big bore kit (anywhere from 470-500) in it while keeping 11:1 compression and a stage II hotcam in it, would i need to run race gas? what are the most effective horsepower producing mods without using race gas? which should i do first, other than an exhaust? does it vary for different motors? and does the efi the ltr and kfx make a different in what i should buy compared to the carbs on the others?

[pro-rider46]

in the 450s, the 11 to 1 will be pump friendly, in fact you can got up to 12.5:1 and still be pump friendly. If your looking to get a lot of power with out the use of race gas, i would get the head ported, oversizeds exhaust valves, kibblewhite springs, hi comp piston( and big bore if you want) stroker crank, exhausts. and that should be just about everything you can do as far as a mx pump friendly motor.

if your just going to do it step buy step, cams & porting are reliable mods to do. the carb vs efi decision is up to you being whether you want to buy a efi tuner, and programs, or a laptop to dial it in. or are you okay with just changing jets. one isnt light years ahead of the other, its just $ and whether you want to d!ck with the carb and tuning.

[mudrunner35]

i will be doing a little mx but it's going to be mostly a trail quad, and i want to squeeze as much juice out of it as the poor hunk of metal can handle:p

[pro-rider46]

Originally posted by mudrunner35
i will be doing a little mx but it's going to be mostly a trail quad, and i want to squeeze as much juice out of it as the poor hunk of metal can handle:p

seem like you are like me.... whata you think of this...v v v..

[mudrunner35]

too much power for stock parts? or something just came loose? or did it just decide to thunder sheet itself

[csr250r]

^^^ thats why i run stock piston/ bore. i would rather not get a awsome start and pick a few ppl off than have that shuff happen.:ermm: