How can you tell the differance between a tbi motor and a vortec motor? Its just a frame so there is no stickers anywhere..

 

Some information here:
4.3L Vortec motors.

One dead give away that it is a TBI motor is that it will have the round air cleaner on top of the motor. The CPI and SCFI motors have a rectangular air cleaner off to the side of the engine bay.

 

it didnt come with the air cleaner and intake manifold.. It just has a throttle body..

 

What is it that you are trying to identify here..? Vehicle information?

 

oh sorry... its a 1991 s10 blazer 4.3l.. i need to know if its a vortec or a tbi..its just a rolling chassis so there’s nothing that identifies it..

 

It will be a TBI. Like the link I provided states, the cylinder heads are of the vortec design even though it wasn't used as a marketing tool until 1992 when the CPI motor was released.