non pi head/pi cam and pi intake hp gains

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^^Yes, a tune DEFINITELY helps. A lot.

I don't know just exactly what you are looking for, but there is set of Comp XE268Hs (which are supposed to make good power) on Ebay right now for a good price. http://cgi.ebay.com/ebaymotors/ws/e...&_trkparms=algo=LVI&its=I&otn=2&category=6755

I was originally going to put these cams in my car, and even got a set, but the seller tried to rip me off and sent me mis-matched cams; and I never came across another good deal thereafter. So I just settled with the PI cams. If I hadn't just spend a couple grand on a blower, I'd jump all over these in a heartbeat.
 
Wait, this is all contradictory of what ive heard in the past, so getting the new PI heads wont really benefit me as much as I think, I always heard the NPI heads were really restrictive:-( So I just need a better cam and plenum and TB? with a good tune and the full PI swap ive heard numbers of around 300hp up from my 225...im confused now.

The entire Non-PI top end (Heads, Cams, intake) together are very restrictive. The heads themselves aren't so much. With a little work, you can actually get a set of NPI castings to ourflow the more popular PI castings.

Truth be told, a PI cam(s), intake swapped NPI engine is down on peak power only about 5% over a stock PI engine. But that's not to say PI heads still aren't the better castings. Low speed velocity mid level flow levels are still better with the PI castings because of the revised combustion chamber design and reduced valve shrouding.
 
The big advantage of putting PI heads on a NPI shortblock is not the improved flow of the heads so much as it is the nice bump in compression which gives you more power at every point on the tach.

If you're trying to save money and do it on a budget then just do the cams and intake. They are awesome and hands down better than any bolt-on you can buy.

Once you start looking past that, then it gets more complicated and you have to start making decisions about what your future plans for the car are. However, if forced induction is not on the horizon then if I was going to go through the trouble of pulling the heads anyway to get them ported, I'd probably just put some PI heads back on instead since a set of decent used PI heads is a lot cheaper than porting & polishing and you'll probably get more real-world benefit from the increased compression from a stock PI head than you would from porting an NPI head.
 
If you're planning on turbocharging then generally you'd want to lower compression so you can run more boost. But, if that's a few years off or you're going to stuff a forged rotating assembly in when it's time to turbo anyway then don't worry too much about it - plans may change between now and then and if you rebuild it, you can put the pistons you need to get the compression ratio you want.
 
The NPI heads aren't as bad as most think but they're still pretty bad. Their intake ports are actually not too shabby but the exhaust is simply terrible. IIRC, they stall at only ~0.350" lift... As well, the NPI valves are smaller than their PI counterparts.

Putting a PI manifold on an NPI head is a problem too since the PI and NPI port shapes are different. A lot of engine builders go to the extent of "port matching" and carefully grinding for gasket matching. But with the PI manifold and NPI head, there's no chance of this because the ports are so different. The result is a step at the interface (port is smaller than the manifold outlet) which interferes with airflow. As well, I believe you need to get creative with the silicone sealer to prevent coolant leaks, again due to mismatches.

PI heads are a dime a dozen. Get a set from a wreckers, freshen the guides, seats and seals and stick 'em on. You're that far into it...why not do it right?
 
is that even with a good tune?!? 10hp seems a little lean for such an upgrade, if most people can squeeze out 10 ponies with a CAI and Pulleys...ive heardof numbers ranging from 30 to 75hp with a full PI Swap, anybody else have any input on this?

Well, let's think of it this way. A 98 GT is rated at 225 hp; a 99-04 GT is rated at 260, a 35 hp difference. People have documented a SOLID 25 hp from the cams and intake. So that's only a maximum of 10ish hp from what a PI motor makes, or in other words, 10 hp not counting the compression bump. But the PI heads on the NPI block boosts the compression as well, which is worth a few more ponies, maybe 10 at most.

So to answer the question, a stock PI H/C/I swap is worth 45 hp on a good day, vs just the intake and cams at 25-30. So you are looking at 15ish hp more with the heads. But, that extra increase in compression hinders you in the future if you are going boosted unless you have a built motor. Back in the day, I was thinking about going with the PI heads, but decided against it on account of the possibility of going blown in the future. Glad I made that decision. :D