|Originally posted by jacknight:|
anyone install a Vortec v8? truck motor? are they like the LS motors? they seem a hell a lot cheaper.
Ignore the captains. The '96-'98 1500 pickups had an L31 Vortec 350, also used a few more years in the big vans. This is rated 255 HP at 4600 rpm, and 330 ft-lbs at 2800 rpm. The 2500 and 3500 pickups also offered the L31, but with less power, what with different exhaust seats, and seat cut angles. At this level, you don't need the 4-bolt mains, and if you get the bad heads, plan on new exhaust seats and larger 1.6" exhaust valves, which is actually a good idea if you get decent valves and pop for a 75 degree bowl hog while getting the new seats cut. But this adds cost.
The L31 used head castings with numbers ending in 906 and 062. If you don't find either of these under the valve covers, then move on. But these 2 casting numbers were used for the 3500s and 2500s as well as the 1500s. And could've been swapped between then and now.
Further, '96 versions, and some '97s, have worse valves. Many of the later valves did come with 30 degree back cuts right from the factory. Even so, they don't flow as well as cheap aftermarket valves, if the aftermarket valves also receive back-cuts.
The easiest way to install this is to swap on a carbureted intake manifold like Edelbrock, Weiand and GMPP offer. But EFI or carb, Archie's '87-up SBC swap stuff will get it installed and bolted up. His stuff is proven, and relatively easy, but if you can do metal fab, you might find it less cost to copy fieroguru.
Carbureted Vortec 350s are easy to push to 400 HP, with emissions-friendly camshafts.
[This message has been edited by Isolde (edited 03-06-2011).]