More on cross-breeding or "Running What You Brung".....

Largely because of emission laws back in the late '70's GM started playing musical engines. Since some engines couldn't pass EPA High-Altitude or California emissions standards they started stuffing any certified engine they had into any body. For example in 1977-79 it was possible to get a Pontiac Firebird with a 231 Buick V6, a 301 Pontiac V8,a 305 Chevy V8,a 350 Chevy V8, a 350 Pontiac V8,a 350 Olds V8, and a 350 Buick V8,a 400 Pontiac V8 and a 403 Olds V8 depending on which model-                                         ( base,Esprit,Formula,Trans-Am ) and what part of the country you lived in. This continued for different models through the '80's. You could also get a Buick Regal with a 301 Pontiac, an Olds Cutlass with a 305 Chevy,a Pontiac Gran Prix with a 305 Chevy, a Buick Regal with a 307 Olds V8, and in 1980-81-if you didn't want the awful 301 Turbo-you got a 305 Chevy in a Pontiac Trans-am. This caused big changes in NASCAR. In 1980 Richard Petty switched from Dodge to GM, mainly because his iconic '74 Charger that had won dozens of races over the years would be outlawed for the 1980 season. NASCAR rules said that bodies could only be 5 years old-thus '79 was the last year the mighty Charger was legal. Petty and crew figured out that the slope-nosed,fastback '77 Cutlass was much more aerodynamic than the flat-nose, notchback rear windowed Monte Carlos that a lot other teams were running. They could go faster with the same amount of power. They won several races in dominant fashion. The other teams protested-saying the car was illegal because it was running the Ubuiqitous Small-Block Chevy Race engine-they said it should have a 350 Olds engine-which obviously would not have been as comptetive. Petty pointed out that GM was playing musical engines with production cars-that it was possible to buy a Cutlass off the showroom floor with a Chevrolet engine under the hood, or a Buick with a Pontiac engine, or a Monte Carlo with a Buick V6.  NASCAR sided with Petty-saying that since GM was doing it with production cars it would be legal to run any GM engine in any GM body. The other teams quickly switched to Cutlasses to keep up. Anyhow-the point I'm making is-if you have or want to buy for example-an '81 Trans-Am or an '84 Gran Prix with a 305 Chevy in it and want to go real fast-it's much easier and cheaper to swap in a strong 350 or 383 Chevy than it would be to try to convert it back to "real" Pontiac power. If you have an '81-87 Buick Regal with a 307 Olds V8-it's much easier to swap in a 350 or 403 Olds V8 ( a bolt-in ) for an instant power infusion than it would be to try to swap in a 455 Buick. If you have a Regal or Cutlass with a 301 Pontiac it would be easier to swap in a 400 Pontiac V8 than it would be to convert it back to "real" Buick or Olds power. If you have a pre-'85 Buick Regal T-Type with a carburated Turbo V6 or an '80-'81 Turbo Formula or Trans-Am with a carburated 301-I'd either go the 400 Pontiac route-or if you must have forced induction look for a wrecked late '90's Bonneville SSEI or Buick Riviera with the Supercharged,fuel-injected 3.8 V6. They have a Roots-type belt driven blower from the factory. They make 240 hp stock-and that could be easily upped by 100 or more with a pulley change and some bigger injectors. Now on the other hand-let's say you have a 4-cylinder '86 Mustang. Nothing against Fords-but they don't have anywhere near the parts interchangeability of GM and Chrysler stuff. You'd be much better off in lack of grief and financial investment by selling the car and just buying another Mustang that already had a Turbo 4-cylinder or "5.0" V8 in it rather than trying to convert it. The point is it's often better to take the path of least resistance when it comes to performance. And were talking about low-budget sleepers here-not Concours Shelby Mustangs or LS6 Chevelles-does anyone really give a shit that a '77 Firebird or an '84 Gran Prix has a Chevy engine in it? Mastermind