I just picked up a pretty complete TPI set up out of a 1991 Z28. I am a little confused about what I have to change out besides the fuel pump and sending unit. Do I have to change the hard lines on the chasis? If I can find a donor TPI car can I use the sending unit and lhard ines from an earlier MAF car or do I need to find a speed density car? Thanks.

 

Sounds like you and 86irocu have the same question. Do a search on this swap and see if you can find people that have done it; then PM them to see what they did.

 

I did a search which is why I am asking. Most of what I found related to tbi to tpi swap. I understand that I need higher psi flex lines up front but I am confused on the hard chasis lines that run from the sending unit to the engine bay. My car is a 1987 with an LG4. This was the only year that carbs came with an in-tank pump so I have sending lines and return lines. I was wondering if this was the same hardline set up that the TBI and TPI cars had or do I have have to scrap these and find a set up from a TPI car?

 

They're probably the same; you might want to go to a junkyard and take pictures, then compare them head to head. If they look like they're bent and routed the same, they probable are the same. From a cost perspective, it would usually make sense just to standardize it even if it was over-engineered for a low pressure system.