Go .21 Engine Question
 

I have the Go .21 5 ports engine, and so far it runs great. i just have a question about shims. i am running 30% nitro fuel, and i dont know if i should remove or add any shims. i took apart the engine and i notice that it has 2 copper shims from factory. should i remove one?

RE: Go .21 Engine Question
 

No just leave them. If you were to run 20% then you could take a shim out to raise the compression but running 30% keep the 2 shims. Thats why they come with 2 shims so you can adjust with % of nitro.

RE: Go .21 Engine Question
 

The Go Tech engines come with a .2 shim and a .1 shim. They come from the fractory ready for 30% nitro.

RE: Go .21 Engine Question
 

your supposed to add the shim thats in the box for break in.

RE: Go .21 Engine Question
 

thank you all. i didnt know what was the purpose of the shim that came in the box. thank you.

RE: Go .21 Engine Question
 

No Problem