I need to put a motor in my 79 gmc 4x4 3/4 ton. It has a very tired 350 in it now. It has a turbo 400 tranny & a 203 transfer case. I'm wanting to go play on the trails and dive off into a mud hole. The truck has to play double duty for a while. Meaning daily driver, well weekend driver anyways. Trying to decide which to go with a stroked sb or a big block. Pros and cons of both would be great. Thanks
Personally I would go with the big block, I have had both and found that a small block is a good car motor but for a truck the big block has more usable power and torque and believe it or not but in the same vehicle the big block will usually get better MPG. Not to mention engine life, a big block has torque at low rpm, the small block is a high winding motor, high rpms means shorter engine life. I have a 1985 Suburban that had a 350, it got 10mpg and was seriously under powered, I replaced it with a 454, got the same, 10mpg, but the power difference was amazing. Matter of fact, within a month the big block blew out the 700R4 tranny, to much power and torque for the 700R4. I am now looking at having the 700R4 rebuilt and beefed up or just going with a turbo 400, which is alot stronger tranny.
Small block & big block both have their own advantages. You can develop a lot of horse power with a big block without spending a ton of money but it is difficult to maintain half decent fuel economy.
You can make a 383 stroker which will give you loads of power but it will cost a bit to do a good job. You can get decent fuel mileage with them if your gentle.
Do a search on Vette engines (Crate engines). when you get them dialed in with computerized fuel injection, You get really good fuel mileage & tonnes of power for almost the same cost!