Originally Posted by IWANTMOREHP
What would I have to change over if I wanted to change my 93' Chevy Silverado 350 5.7L TBI to a 95 5.7L Vortec?
1995 is not a Vortec, L31 commenced with the 96 model.
You need to be a bit more definifive with what the 95 is, a Vortec would not have TBI it has a thing called Central Sequential Fuel Injection. Aside from the words Fuel Injection, it shares nothing in common with TBI.
That said, TBI can be adapted to a Vortec headed engine by using a GMPP or Edlebrock intake that bolts to Vortecs at one and and TBI at the other.
The other simple swap is to use the Swirl Port heads off earlier engines and the TBI bolted to a Vortec bottom end.
Some confusion comes in 95 5.7 liter engines as late production started using the 880 Vortec 4 inch bore block. But these used Swirl Port heads and TBI, the only thing Vortec about these engines is the roller cam block. One also needs to be wary of 305s which were called Vortecs for quite some time before 1996, but never had L31 style Vortec heads on them, just the name is all.
To put a true L31 into a TBI vehicle and use the CSFI of the Vortec will change the fuel system starting with the in-tank pump, fuel lines, computer, and wire harness. A lot is involved with this swap.