Ok, I have an LO3 that is basically daily driver. I am thinking of doing some major engine mods when it goes out on me. I'm currently at 143k. So I still have a little while. Anyway, I was thinking of and LT1 cam that is pretty reserved powerwise. Or are they all the same? , Victor Jr. Intake Manifold and Vortec Heads on my current 305. But, I have heard something about putting new heads on an old block. Is there something wrong with that? Anyway, If I was to perform this upgrade in performance, what kind of gas mileage could I expect? If that will make it really low, do you have any other ideas to increase power while keeping some sort of gas mileage that can make it driving friendly?
Thanks

Tyler

 

well i got a 350 tbi with 330 hp and running like crap i got it to go 22 mpg at somewere around 80 miles per hour with a few nice pushes and jprevest says he has gotten 27 out of this motor so i think its how good can you keep engine running, and also what gears you have in it.

 

Well, right now I have the 2.73, or whatever. If I do go with this, I will probably keep those gears, just to retain some driveablility in the car. So, with this, i will be able to increase horsepower, yet remain prettt efficient? So it is pretty much all in the tuning then?:rockon:
Well, if anyone knows of all the stuff that needs to be tuned in order to run pretty good, let me know. It seems my stock LO3 has been running pretty poor gas mileage. But I havn't really ever taken the time to actually check it. I guess that would be a good idea.

 

While not answering your question, I noticed you are thinking of putting vortec heads on your 305. Now, the "nice" vortecs everyone raves about are for the 350, and have 64cc (correct me if I am wrong, please) chambers, are refered to as L31 heads(i dunno the actual casting number off hand, though. Go to mortec.com). The 305 vortec heads are vortecs, in name. Yes, they are a ton better than your stock heads, but do not flow as high as the L31. But they will keep a good compression ratio(they have 56cc chambers...). I am pretty sure this is all accurate, but if I am wrong on anything, say something!