I've asked before and got good info on peticular info. Thank you!!! Now I ask about interchangeability of my 1990 tpi 350..... I've found out that a 1990 vette motor has no internal egr.... That sucked.... Well, heres my goals........

I'm looking to have an emissions acceptable performance motor for my 1990 GTA Trans Am. I've looked hell and high water for that online. Too tired....I wish to buy a motor for under 5 grand. GM Performance has a 383HT that is stated to be emissions compliant but it is slated for 96-99 trucks with vortec heads. WTF is vortec??? does it have EGR in head??? Why does a 3rd gen guy have to struggle with wondering????? 87-95 block is gen1. why do the heads have to be so friggin elusive as that what the hell is vortec and then lets confuse the world on LT1????

Help!!! Then sticky for the rest of the dumb people like me. Thanks.

 

"Vortec" is GM generic marketing name for their truck engines. With regard to Gen I SBC's, it is the '96-'99 (and a few '00) engine, both 305 and 350 versions.

The production 350 heads of that era happen to be pretty good for a mild performance engine. They have the same chambers as LT1 heads, and raised intake ports vs. "regular" Gen I SBC's that enhance the intake flow (and require a specific type of intake manifold). They did not have the exhaust cross-over passages that Gen I engines used for the source of exhaust gases for the EGR valve in order to improve exhaust port flow in the center ports (same approach as the Gen I aluminum Vette heads). If equipped with EGR, there was a pipe to route the exhaust gases from the exhaust manifold to the intake manifold.

"LT1" was used in Vettes from '92-'96, f-bodies from '93-'97, and some '90's B-bodies. It uses a "reverse flow" cooling system that routes coolant from the radiator to the heads first to give more consistent temperature control of the combustion chamber. This family of engines is usually called "Gen II". Heads and blocks from Gen II engines are incompatible with Gen I heads and blocks without extensive modification, although cams, cranks, pistons, rods, bearings can be swapped between Gen I & Gen II.

The GMPP 383HT to which you refer uses "Vortec"-type heads, and will basically bolt in place of a '96-'99 light truck engine. It would be emissions-compliant in that application. You could use it in a TPI application, but you would need a Vortec-type TPI base.

If you want a TPI performance engine for under $5k, SDParts.com has you covered. http://sdparts.com/details/scoggin-d...nter/sd360vtpi
Although they don't state they have emissions-certified it, it would take a pretty sharp inspector to catch it (they do have the EGR kit for it). Word is California is allowing light truck engine swaps into passenger cars these days, so you may be able to get by with it. Most likely, though, if you rolled up to the inspection/test station with that engine, they wouldn't give it a 2nd look. It should sniff clean with a fresh tune (plugs, wires, cap, rotor, etc.).