Which are the best heads V3 or V4 or are they as good as each other?

 

thats what i've been trying 2 find out too

some said v4 months ago now i'm told v3 cams are better???

 

well i have a set of both!! so i want to know so i can use on my new project

 

The version 3 runs a slightly wilder cam profile, so would choose them over the version 4 heads especially with a big bhp or 2.5 build.

Banny

 

a lot of people say exactly the same thing banny, but the guy at surrey rolling road told me that ver 4 and ver 5 heads are the best.... so im not realy sure as yet

 

The version 5/6 are the best but you cannot make them fit the version 3/4 cars as the inlet manifold pattern is different. The version 5/6 also have issue of cracking round the spark plugs sometimes. Between the version 3/4, I would prefer the version 3 setup but there is not much in it and would not complain if I had to use version 4 heads.

If I was going to trouble of modifying my inlet manifold to fit newer heads, no doubt I would go for the AVCS heads as they help greatly with turbo spool and outright torque/bhp.

Banny

 

how can you tell the difference between sti and wrx?

 

thats more like it thanks for the explination banny

 

The WRX and STi share a common head casting - its the valvetrain and cams which differ.

Mick