[86pony]

I am considering swapping my stock 86 heads for a set of stock 87/89 heads that have been ported.
Will this work with the flat top pistons, or do i need to have the pistons machined for valve clearance.
Also, I would like to upgrade the intake manifold, but am not sure what would work best on an otherwise stock engine.
I have heard of some people using an explorer manifold, any thoughts on this?
I am trying to gain a few extra ponies on a tight budget, so any help is appreciated...