I was wondering how the primary fuel rail needs to be modified in order to accept stock 850 injectors. Thanks in advance for any info.

 

Mill a 1/8 of a inch off the top....

 

Nope... mine fit fine but I had the rail ported and then tapped for AN fittings

 

As jim said, easiest thing to do is just remove an 1/8 of an inch from the bottom. I have done a couple with just a bench grinder. Worked perfectly each time.

 

bottom???? u mean top!! the bigger holes no? at least thats how i did mine

 

yeah you mill the top of the rail 1/8 in. so when the injectors go in they sit lower. since the stock 550's are taller injectors.

 

a bit off the top to get them to seat properly, then a bit off the bottom because the 850's don't go down as far and you don't want the fuel hitting the wall of the casing.

 

Wha?.... I have never heard this bottom of the rail part ever...

 

what he said ^

 

you can mill the cone that the cone part of the injector rests on as well as the top of the rail that the cover rests over. Milling the cone gets it lower and milling the top lets it clear the cover. I think that's right? I had both done. The cone milling makes it lower to get the spray closer but its a strait pattern anyhow. If it was an outward V spray pattern then lowering it prevents it from hitting the walls and spalshing back towards center. I repeating the explenation by memmory, so i'm not shure if I explained it correctly.