I have a 1991 350 c1500 that is said to have a Vortec 98 engine from the guy that i got it from. I have to get the piston rings replaced so I'm just going to get a new long block considering the expense. Question is...

Whether or not it's a 91/91 vortec or 98/98 vortec.. can I use the intake on it? I'm needed to basically buy a long block from autozone and put it in this week so I need to know soon

 

I am not certain, but didn't the "VORTEC" engine line come out for the 1996 model year? Seems to me that both the 1991 and the 1998 would have the 5.7L (350) V8 engine.......but bear in mind that GM did a lot of weird stuff with their small-blocks.

The block, rods, camshaft and pistons might be very similar, but there could be huge differences with the fuel injection system, manifolds, throttle body/intake, etc., etc.

You need to get some VERY GOOD advice on this topic - and this is probably the best place for it. :-)

 

The Vortec motor did start being used in 96. If it has a Vortec motor, no matter what year 96-98, you need a Vortec long block. The Vortec motors have different heads than the previous years, 95 prior, 5.7L motors.

With that being said, if you put an original 1991 type 5.7 long block back in, you will need an intake manifold and throttle body to match. The other option is to do a short block, have the Vortec heads done at a machine shop and then use the heads and intake.

Hope this helps.