2 Stroke Porting

[1sick6]

Hey im just after some input on porting,

I recently bought a old 1982 YZ100 and it came with a spare parts engine, I noticed some 1 had drilled 2x 6mm holes on the intake side of the barrles and they lead straight down to the crankcase.

 

• By doing this what sort of power grains could be expected?
   
  
• Would it be top end power with a noticable loss of bottom end performance?
  

I noticed Cheetah cubs have simular intake port holes.

 

any info on this would be great thank you, Paul

 

 

 

 

Stock Banshee intake ports

 

421 cub intake ports

[CFH87]

Their called worm holes geared more toward top end performance and drag racing.

[BigRed350x]

I read somewhere online that the holes help smooth out power delivery and make for a better power curve.

[CFH87]

I'm just going off of what kevin from HJR said I was gunna have them added to my dune port but he said it makes the power band peaky. And that's why their added to a drag port for mor power up top. But to double check I would talk to a site sponcor for porting like kevin of jeff.