hey, i am going to be installing a 350 Tbi from an 87 Chevy truck into my 89 305 Tbi f-body...
Will I need to use the ECM from the truck also for it to perform correctly?
I am using the stock 700r4 trans. Is the bolt pattern the same on the flywheel, or will i have to use that from the truck too?

 

I aint tryen to scare you but i heard that 350 would only be a couple horses more then the 305

 

well the 305 has a rod knock...and the machins shop wants $500+ in order just to set up the block, not to mention rings and new bearings. The 350 will cost around $400. So the HP gain is not the main idea, it is the longevity issue of the 350 vs 305

 

I did this swap last year and trust me you will be happy you did. The 89 chevy truck LO5 350 had 210 hp and 300 ft lbs of tq.Thats not great, but you can do alot with it I am running mid 14's with minor bolt ons,and with the new setup I am working I will be breaking high 13's soon.Everything will bolt right up no problem.Also get the throttle body out of the truck it has bigger injectors that you will need in order to have the right air/fuel ratio. You will need a different chip, but I dont know if you can use one from a truck. I am using the cop car caprice chip. go to tbichips.com and email the guy there ,and ask him what youll need , he will tell you , that you need a new knock sensor and esc module ,but I havent changed those and mine runs fine.You will defenetly be happy that you did this swap.Good Luck.