305 to 350 Engine swap
 

I have an engine build in the process right now and it is ready for an intake. I have a 93 Chevy 1500 it has a 305 TBI in it right now and the motor i want to put in is an older built 350. Is it easier to get a new ECU and go with the TBI setup or is it easier to convert it to carburated? Any advice would be greatly appreciated as i want ,my truck ready for spring.

RE: 305 to 350 Engine swap
 

either way is easy. if you wanna stay with the tbi you do not need a new ecu, just larger injectors in the throttle body. all that 305 stuff should fit up to the 350 if it has centerbolt valve covers it will. i would recommend staying with the tbi, its what i did in my 305-350 swap and i thought it was really simple.

RE: 305 to 350 Engine swap
 

what about the knock sensors etc?

RE: 305 to 350 Engine swap
 

unless your not worried about gas mileage i would stick with the tbi. like stopspazinout said everything should fit on the 350 from the 305 the engine blocks are pretty much the same besides the bore. knock sensors and everything else should work. in my opinion i would stick with the tbi it gives you better gas mileage better acceleration.

RE: 305 to 350 Engine swap
 

the only thing that i know is that when i replaced my regular 350 with a built 350 the tbi cant keep up with it. i have to much cam for the engine.. also you can get a lot more power out of the carb. you just need a different intake a fuel pressure regulator to dial down the electric fuel pressure and then just hook up the linkage and your ready to go.. i beleive they even have kits for the linkage.

RE: 305 to 350 Engine swap
 

you could reuse all those sensors if theyre good but since your doing engine work i would replace things like knock sensors anyways. one thing youll need to switch for sure if staying with a tbi is the electronic spark controller. make sure you put one on for a 350 and not reuse that 305 spark controller.

RE: 305 to 350 Engine swap
 

i would go ahead and put a new everything on it while youre at it. new water pump, knock sensors, oil pump,even new o2 sensors,whatever you can do. IMO, i would keep the tbi and make it easy for you. the 305 tbi will work on the 350, but you could get a majorupgrade from holleywith a 650 or 750 cfm for around $300-400. also, you might as well throw in a new cam. dont go too radical tho. if you keep the heads, im guessing you are keeping the intake too. those will swap right over

RE: 305 to 350 Engine swap
 

Use the 350 block with the 305 TBI unit. Then go to TBIchips.com and tell him what you are doing. He will make a PROM for you that will allow the TBI unti to work with the higher displacement of the 350. Make sure the 350 has centerbolt heads like the 305!!! But I would look for a set of VORTEC Centerbolt heads first, the truck will run a SH*TLOAD better with those heads over the TBI heads. Trust me on this!

RE: 305 to 350 Engine swap
 

I just did a complete engine build my self and yes the vortec heads are a good buy. 289 dollars each on jegs i also got a .262/.269 comp cams exteme energy cam and also a GM Performance intake manifold. My truck is very torquey

RE: 305 to 350 Engine swap
 

im in the process of building my 355 now. i didnt get vortec heads, but i got a set of S/R touquer heads from Wold products for around $800. they are working pretty well on my 305 now. idk what the specs are on my cam but its bigger than i need right now. as far as intake, i just got a new edelbrock performer intake. i think it was $160? i dont remember.