i have 305 im puting in a 355 tbi.Im new to this i have a 350 bored .30 over so thats a 355 im gonna us a lt1 cam also since i have it now i have trw flat top pistons heres the link to what i have to http://www.summitracing.com/parts/SLP-WL2491NF30/
if you just look up them up there trw l2491 30 or so.i have 193 tbi heads now but im buying a set of 906 vortec friday what all needs to be done to the heads i have read alot about the heads cracked and all im gonna get that checked out right after i buy them there out of a junkyard off a 99 chevy truck.I found this to http://www.alexsparts.com/products.p...YD-FLAT-TAPPET he also has a set for roller cams will this work remind you im not rich if this works and all how much power could i make with a 355 vortec the block is done honed everything and the cranks a scat crank the machine shop did this cam bearings power cly hone cylinders grind crankshaft r&r pistons jet hot cleaning.what else will i need for the motor swap im keeping tbi gonna get new bored out tbi and everything to go with it thanks for your time and advice
brian

 

Im in the process of a similar build, and why are you going with the LT1? Is it free? For what you will spend on that cam, you can do much better. Im using at LT4 Hot Cam, getting .495/.495 with 1.5 Full Roller Rockers. I have the same heads, and I would make sure to get the flux checked. After that it really depends on the cam you choose. If you stick with the LT1 than you dont need to "upgrade" the heads per say. Get a vavle job done on them, and if you think you may go bigger with a cam down the line, have the heads machined and screw in studs installed. This will allow for great lift later.

As fr HP, with the LT1 you will probly be around 300-320 hp. Big factors will be intake, headers, exhaust, and the gear ratio you are running.

Good luck