Motor I'm building at the moment is a vn block, blue heads, going into a ht. So no need for emission stuff. I need a single plane manifold for it. When they advertise "suit red heads only" is that only because of the emission controls? In other words can I bolt up a "red head only" manifold to my blue heads since I'm running no pollution gear??

ide say its to do with the EGR, on non-pollution (non EGR heads) the intake manifold has a single middle bolt hole, but with the pollution manifold (with EGR) it has 2)

You may want to check up on the emissions side of things a bit more as whilst the car it is going into is old enough the rules may apply to the age of the much younger motor and the emissions standards for it. Corsa

Being a vn block you need emissions. Its if you go ht block with VN heads that you don't. I could be wrong but thats my understanding..

Ah well. I will work my way around that, still won't be using them. So the centre bolt holes...they obviously won't line up?

no not at all edit: you can see the difference here; no egr egr Some original photos have not been recovered yet.