What's the best way to modify an early manifold to suit the different middle bolt angles on the 87 and up heads? Is it best done on a mill, a drill, with a file, dynamite or what? Any pics?

I believe there is an Edelbrock manifold that is set up for both angles - anyone have any pics so that I can see how they did it?

Is the angle of the centre 4 bolts on the new heads 73 degrees [as opposed to 90 degrees]?

 

summit/jegs sell little pieces that slip into the holes and act as a "guide" for your drill bit (hand drill) for the new angle....


heck its just fine to shuv a drill into it and "waller it out a bit"


Get shady tree mang

 

If you do that, the bolt heads won't sit flat on the intake surface.

Is there some way get them to sit flat, other than spending LOTS of time with a dremel...

 

Other than a mill, no

The idea isn't to have a flat bolt, the idea is to have it torqued and held to say 35lbs

Whether the bolt surface is flat or not wont prevent it from holding at 35, just make it ugly

 

I could've sworn i saw little adapter shims being sold with some of summit racings manifolds that allowed for both bolt hole angles. Check on their site, or give them a call...

Hellraiser