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markeb01 · 11-21-2009, 05:02 AM

If you’ve already read a LOT about the fixing up the six, I’d spend a bit more time considering which is more important to your enjoyment of owning the truck – the cool factor and long term economy of the six, or the fun factor of driving it with a V8. Seems like everyone is broke right now and gas isn’t going back to 30 cents a gallon any time soon. The 6 with a 5 speed would be more fun than the six with a 3 speed, and economy would improve. They sound cool on cruise night with split pipes, are pretty rare hopped up, usually drawing a crowd. All the mounts, hoses and pipes are already there, and if you added a couple of gears now, you could add more power rather easily later as the budget allows. The six will almost always be cheaper in the long run, because once you swap to a V8 you’ll never run out of things to upgrade.

On the other hand if you really enjoy blasting around quickly in an old truck that was never designed to go that fast, the V8 wins hands down in the fun factor. Now living on the limited income of semi-retirement, a six cylinder in my truck would really be practical for economy, but I have a couple of late model jelly bean cars for transportation that get great mileage. My truck is mostly for fun, so I’d rather launch like a rocket than save money. I’m running a 350 with a Richmond Super T10 four speed and 4.09 gears in a Dana 44. 60 mph would spin the engine somewhere around 3 grand, but most of my driving is on surface streets where I just don’t need to twist it that tight. Consider what type of driving you’ll be doing when deciding final drive gearing. If it's rarely going to travel far or at freeway speeds, 3.73’s or 3.90’s can be fun. They do of course stop being fun if the truck needs to be more general purpose and doesn’t have overdrive.

If you decide to go with the V8 swap, I agree with TheDark1 on the durability of the stock 3 speed. Years ago I put a Corvette 283 in front of an old puny 54 Chevy passenger car 3 speed with the torque tube driveline, and it held up for years before the spider gears in the rearend finally broke. Concentrate on the engine swap now. The major things are pretty easy to plan for but there will always be a bunch of things pop up you didn’t expect. It doesn’t take too many of those surprises to add up to $1000.

11-21-2009, 05:02 AM	#7
markeb01 Senior Enthusiast Join Date: Feb 2007 Location: Spokane Valley, WA Posts: 8,356	Re: Powertrain thoughts for my project? If you’ve already read a LOT about the fixing up the six, I’d spend a bit more time considering which is more important to your enjoyment of owning the truck – the cool factor and long term economy of the six, or the fun factor of driving it with a V8. Seems like everyone is broke right now and gas isn’t going back to 30 cents a gallon any time soon. The 6 with a 5 speed would be more fun than the six with a 3 speed, and economy would improve. They sound cool on cruise night with split pipes, are pretty rare hopped up, usually drawing a crowd. All the mounts, hoses and pipes are already there, and if you added a couple of gears now, you could add more power rather easily later as the budget allows. The six will almost always be cheaper in the long run, because once you swap to a V8 you’ll never run out of things to upgrade. On the other hand if you really enjoy blasting around quickly in an old truck that was never designed to go that fast, the V8 wins hands down in the fun factor. Now living on the limited income of semi-retirement, a six cylinder in my truck would really be practical for economy, but I have a couple of late model jelly bean cars for transportation that get great mileage. My truck is mostly for fun, so I’d rather launch like a rocket than save money. I’m running a 350 with a Richmond Super T10 four speed and 4.09 gears in a Dana 44. 60 mph would spin the engine somewhere around 3 grand, but most of my driving is on surface streets where I just don’t need to twist it that tight. Consider what type of driving you’ll be doing when deciding final drive gearing. If it's rarely going to travel far or at freeway speeds, 3.73’s or 3.90’s can be fun. They do of course stop being fun if the truck needs to be more general purpose and doesn’t have overdrive. If you decide to go with the V8 swap, I agree with TheDark1 on the durability of the stock 3 speed. Years ago I put a Corvette 283 in front of an old puny 54 Chevy passenger car 3 speed with the torque tube driveline, and it held up for years before the spider gears in the rearend finally broke. Concentrate on the engine swap now. The major things are pretty easy to plan for but there will always be a bunch of things pop up you didn’t expect. It doesn’t take too many of those surprises to add up to $1000.