situation: cant afford headers. i was told that the tpi 350 vette exhuast manifolds outlets are somewhere like 2.25 or 2.5in, in comparison to the tpi 350 f-body 2.0in outlet manifolds. is this information true, and will the vette manifolds work on an LO3 f-body?

 

I'm not sure what year 'Y' car you are looking at, but the older (like L81) 'Vettes had tubular stainless exhaust manifolds (400SS) with 2½" outlets, AIR fittings, and the whole shee-bang.

 

for example, like a 90-91 vette. they are tpi, arent they?

 

Yes, the L81's had tubular manifolds (tunned exhuast) depending on what year. I know the L42 manifolds have a 2.5 outlet cast iron. I fitted the old 350 manifolds from my 76 on my car when I was installing the headers and they actually fit nicely but would require a custom Y. Note I noticed no power gain between 1.3/4 long tubes and the stock manifolds on my truck.

 

im sorry, what is an L81?

 

My uncle has an '84 Corvette with a Cross Fire 350, and its got the factory tubular manifolds.