Correct. I would not advocate doing these yourself (unless its something you do for a living) but rather finding a shop with a good history to do them.

Ok cool thanks guys this helps me out alot....

now to find a good speed shop... i should ask machinist buddy if he knows..

L27 heads and S1 L67 heads are very similar to Turbo Buick (GN) heads. Finding a shop familiar with those shouldn't be difficult, but make sure you point out that you're not turbo or SC. Heads can be over-done.

ok will do.

just one last question, how much more power will i get from just this...

and i take it my throttle response will get better to?

Just the heads? 5hp maybe. Very little. The problem is probably more in the LIM porting than the heads.

Possible snappier response, but again, the LIM may prevent that.

I would say it depends on the job done to the heads. I picked up almost 40whp from mine

Series 1 LIM issues are the restriction. Todd, you ported yours and did alot of other supporting stuff. He'* talking about simply 'cleaning up' the ports in the heads on a car with a restrictive LIM (ports don't match well).

Point taken although I still think 5hp is conservative.

is there a Easy way to fix the LIM problem??

Gotta remember, Todd. You have a much higher flowing setup. An L27 isn't going to benefit that much from simply polishing head ports while removing very little material when he doesn't have a supercharger sitting up there stuffing air in, and his LIM outlet ports are actually smaller than the intake ports in the heads.

I seriously doubt if this type of work (as it'* described in this topic) would even be noticable without other supporting work done at the same time.

The port configuration differences between Series1 and Series2 are significant.