Engine build-up....I have a delimma

[five_o_stang]

Ok...I'm a college kid workin' on a slim budget here so keep that in mind.

My car is a 91 LX 5.0. I've had a T-5 swap and full exhaust and that's pretty much it for mods. The motor has 165K miles on it. I've had the car since it had 83K...about half the cars life. As far as I can tell the car was well maintained before I bought it with the only modification being the removal of the air silencer. The engine bay is by far the cleanest stock bay I've EVER seen on any 5.0. There have never been any leaks or internal motor problems of which I'm aware. It burns about almost exactly a quart every 3000 miles which is said to be normal for that many miles. Oil pressure stays just above the M in NORMAL and always has. Pretty much the car is perfect.

Ok...that's the good news.. here's my delimma. I'm finally ready to start bolting on all the standard go fast goodies and am planning to strap a blower on it when all the regular motor work is complete.

Given that I plan on a 450hp set-up in the long term. Should I go ahead and start a build up from scratch...w/ a fresh shortblock (preventing any down time on my daily driver?)...OR given the good history record of my motor at hand...just build up the motor ...strap a blower on it and see what happens? I would like to know what kind of reliablility i should expect outta an older shortblock. Anybody else have a high mileage motor with a supercharger on it?...What have been your experiences?

Thanks guys.

 

[89white50]

the funny thing is i am also a college student attempting the same thing...but less hp. My motor has about 125k on it and burns the identical amount of oil. I completely resealed and put new bearings in over the summer. My 89 has yet to see a winter, so its in good condition as well.
Anyways, i read that it was better to use your original block because it has already been through all the heating up and cooling down, making it more reliable. Just make sure you check the deck and piston walls to be correct.

 

[Andres2882]

While its true that a seasoned block won't consume oil for the reasons you said. I doubt your going to find a brand new 302 out there. Most builders will use a used block anyway and it normally doesnt even cost that much more. Mine is going to cost $75 more and I'll have a spare engine just in case.

 

[five_o_stang]

I"m not lookin' for a new preassembled short block...if I do it myself I'll find a used one...have it fluxed and cleaned..then i'd take it, hone it and assemble it myself. I just don't know if it's really gonna be all that necessary if my current shortblock is better than I want to give it credit for.

 

[leakyfaucet]

My take on it is this: The higher mileage engine isn't more likely to snap a rod or anything like that than if it was newer, but your compression may be low, hindering your ability to make power. I would do a compression test. You can also do things like pour in a bit of oil in each cylinder to see if the compression #s go up. If they do, your rings are worn.

If your rings are fine, I would keep the stock shortblock.