So, after this whole "it's a head gasket leak, its not a head gasket leak" debacle with my engine puking oil, I've pretty much decided I'm driving the car for another month or two (which will only add about 500-1,000 nice-day miles to it), then parking it for the winter. Over the winter, I want to play with the stock tune and slowly teach myself tuning in whatever spare time I actually get...but that's another post...

I've set a goal of 275-300 net HP for whatever I end up doing next year...which will either be rebuildingand building up the 305, or swapping in a very mild 350. The problem with the 305 is that I don't currently know of a quality machine shop that can do the work, but I have the advantage of keeping the original engine with the car...something that to me is a positive for down the road. This is a cruiser, not a race car, so maintaining originality somewhat is important to me. The other problem with the 305 is I obviously will not get the same HP because it is smaller...but like I said, originality and the uniqueness of having a built 305 is more important to me than an extra 25-40hp.

Conversely, the 350 (likely the 350 H.O., which at 330 gross hp with a carb would likely still be 300hp with TBI and some nice headers) I can purchase directly from GM and pay someone to drop in the car, and it comes with an unbeatable warranty. My primary question is, has anyone on here tried tuning this engine? Are the specs of this engine tuner friendly? My goal is 25 MPG at a 75 MPH cruise, as I do drive this car on long trips for about 4-5,000 miles a year.

To get back to the 305, my intention would be to rebuild the engine and likely add the Vortec heads and intake to it (rendering my Performer intake useless which I don't like, and I guess the Vortec intake does not allow for a 14x3 air cleaner well either...), and likely an LT1 or LT4 cam, along with the necessary TBI injector and fuel pump requirements to get me there. With a full exhaust, is 275hp possible from this setup? The lack of EGR on the Vortec intake is unimportant, as for '08 MA, believe it or not, will not require smog inspections anymore!!!

One key question for me is, will one be eaiser to tune than the other? I can get the car to shops that can do the mechanical labor for me...but being able to tune is what scares me. I want this thing to run right, and I want to be able to make adjustments as needed...I've seen people on here say that they had shops before tune their car, and later on they end up with issues. If I can do this aspect myself (I already have a great laptop, and just need to read enough to figure out what I need for tuning software), I feel set for whatever crops up with the car.

I know a lot of people are just going to say to swap the engine...but I think I've said this in other posts...having the engine that came with the car still in it would be fun for me. Plus, it won't be cluttering up my garage on the floor, either!!!

Thanks to anyone that can help. Also, is it reasonable to expect my 114k mile T-5 to last long behind this in normal driving? It won't see the track. Eventually, I will swap gears and the tranny too, but getting married next May means I need to stretch this out a little...thanks.