Thanks for all help and suggestions in advance....I have a 2009 gtr non cdi motor that I bought used about a month ago...motor seemed to run fine at the time but after getting it set up for my boat and water testing I found it to be low on power especially under load...I have since ruled out ignition and fuel...the usual suspects....and just ran a compression and leak down test today. I have just over 100psi on each cylinder and the leak down showed I was losing through the intake side of the valves. So now that I know I am going to need to tear it down for a valve job and to inspect rings and cylinders....would you folks recommend going ahead and boring the cylinders and getting bigger pistons as well as decking the heads .040 with a port and polish and a cam? The motor is going to be pushing a 1854 f86 with 3-4ppl and a dog with 6+dozen decoys depending on the day and a blind.

Just do the heads, get a cam, gut the exhaust, and add a carb. Dont bother boring.
What % leakdown one each cylinder?
When you did the compression test, were you holding the throttle wide open?

your PSI is low, BUT did you hold the throttle wide open while cranking? Briggs rings are garbage anyways, so 15-20% leakage is the norm for a healthy briggs. Honestly a good valve job will make your motor feel a lot better. Unless you have an out of round cylinder or wall damage, no need to bore the engine IMO.

I didn't have the tools for a leak down test available so I had to take it to a service center to get it checked. I will get the full details on leak down percentage when I pick it up this morning and post their findings. Won't know about cylinders until I get it back and open her up....recommendations on a cam....305...308?

Cam choice depends on what you want to achieve. You need to know more than the "lift" of the cam to determine which one.

I got a chance to talk with calen at delta this morning....I think I am going to go with a 305 cam with the timing advanced 1.5° and possibly just go with a set of delta heads with .045 decking and the high rev valve springs with stainless valves. Considering deleting the crank case gasket as well to help alleviate with chances of oil leakage and depending on the state of the cylinders as to how I proceed with the bottom end.....

That sounds like a Good plan.

Just out of curiosity any easy solution to getting these heads off without feeling like your going to break them

The bolts, or the heads themselves?

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Bolts were not an issue...it appears the appropriate amount of antiseize was used but when trying to pry the heads off I can almost see the cooling fins begin to flex without so much as an ounce of give between the head and block....no improvement was made even with a few moderate taps of a dead blow hammer.

How many bolts did you pull out of each head?

I removed 5 from each head that were 14mm

There's a 6th, dude. Between the pushrods under the valve cover. They should come right off then.

Without a dead blow.

Call me in the morning before you potentially do some damage. It's not from lack of effort, intent, or mechanical skills that you almost had broken heads. It's simply you're learning about these engines and didn't know. You may have just gotten very lucky you didn't tear up those heads (remains to be seen), but even with my hatred for that briggs I'd not like you to tear something up just because you didn't know to ask something. Then you'd be out some money having to fix it. From experience, that sucks.

After thinking about it....I probably had been awake entirely too long to have screwing around with the motor this morning after having been up for 27hrs with only a cat nap....I simply forgot about that 6th bolt and Russ I knew better even this morning than to put enough torque to harm anything. ....I probably should have just tried getting some sleep but that first midnight shift in the rotation always throws me off

LOL that 6th bolt!!!! Glad you found that a smack with your palm frees the head.

Some days it takes a smack and just enough down time for the monster energy drink to kick in to get the cogs free spinning again

It doesn't take much to warp those heads, so it's a good thing you're getting them decked.

I will most likely turn them in as a core charge to delta and get their heads with the porting and polish with .040" larger 1 piece stainless valves and the high rev pink valve springs preshimmed and decked .045"

They have to be in good shape to get the core charge back though. Damaged or tinkered with heads, they will be garbage to Delta

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Heads are off and no damage appears to be present and no warpage....just a lot of carbon build up from what looks like previous owners using cheap low quality gas