Hello,
I am new to this site. I have a 78 ss that has the z15 code and came original with the 350. I know in 78 horsepower was week to say the least. The engine has been modified a little. I want to go to a TPI set-up. How much more power can I expect to get or will it be easier just to swap to an LT-1. John

The obvious answer is go with the LT1 there is really no comparison. Adding the TPI to your 350 will give you a noticeable gain in low end torque and some additional power. But consider the pros and cons if your engine is stock with high mileage it would need to be rebuilt to take advantage of the TPI it would also need a newer cam just to make it worth your while. Right now you can find very good deals on a complete LT1's with transmission for not much more than what it would cost you to convert your 350. I did convert my 350 in my 83 El Camino but the engine was originally a 76 Camaro engine which I rebuilt with better heads and a after market cam along with a few other mod the TPI made a tremendous difference but still does not compare to the LT1 in my 93 Corvette. Bottom line it will take about as much effort to put the LT1 in as it would to convert your 350 but you will get more bang for the bucks with the LT1. Harald K

Thanks,
Once I get it back from paint I have a lot of interior work to do. Once thats done. I cant wait to drive it. I will probably drive it as is for a while and then maybe this winter go with the LT-1. John

That is a wise plan. Drive it for awhile and take your time to figure which way you want to go. Once you settle on the course of action read all you can on the swap it has been done quite a few times and you will have no problem finding information on what it takes. Have fun Harald K