More random engine swap musings...

[derf]

Since I'm still in the "what if" stage for my next project, I have come across another idea and wanted to gather some input.

My vague plan is to find a GM truck of some kind and grab the whole drive train, computer and wiring harness and swap it in. Initially I was focused on the 5.3/4L60. But lately I've been thinking about the 6.0/4L80 from a 3/4 ton.

I know the 6.0 has more torque and towing capacity while having a little lower fuel economy. I know the engine mounts would be the same and I'll probably have to fab up the trans mount either way.

I'm sure there will be a cost difference.

What other pros and cons can you identify?

Is there any reason to avoid a 6.0?

[derf]

As I sit and crunch numbers, it occurs to me that if I stick with stock size tires or even 30x9.5s the 4L80 overdrive keeps the engine in a reasonable RPM range with stock 3.31 gears meaning I can avoid paying big money swapping gears.

[FSJ Guy]

If you can find a 6.0 for not much more $$, why not? I can't imagine that the mileage difference will be that noticeable. And we don't drive these things looking for super mileage anyway. OK, at least *I* don't..... :- p

Sure, crappy mileage is a bummer sometimes, but no one EVER complained about having too much power from their engine.

[derf]

Yeah, mileage isn't a top concern.

But with 30" tires and 3.31 gears I'll be loafing along at around 2100 RPM at 75 so mileage won't be stupidly bad.

And I'll have decent torque to pull a small camper or the like.

[Nikkormat]

Sure, that sounds like a good idea. And I'll take that crappy old 401 off your hands in the mean time.

[Cheap Hobby]

You should also consider your springs in the budget. I would wait till done then have the springs made based on weight as loaded for primary use and desired ride height. Crappy suspension will effect your towing pleasure even with a small camper. We have a 1968 Aristocrat 14' bought for the 79 with the equalizer hitch and factory HD hitch I could make up for the rear sag and gear in the rig. The largest we pulled was a 24' but would do that now after beating the springs up for 13 years.

[derf]

Sure, that sounds like a good idea. And I'll take that crappy old 401 off your hands in the mean time.

Truck Norris is keeping the 401. I'mconsidering all of this for a Wagoneer project once I'm done with that swap.

[Nikkormat]

Ah I see, I thought you were already tired of the 401.

[derf]

It's not even back from the machine shop yet. Though it should be ready this week.

[Nikkormat]

I know, I was just joking around. Giving you crap for an ls swap as it were.
If I had to do my engine over again, with the junkyard resources I have now, I would have spent less doing a carbureted 5.3 lm7. And a little more than my 401 cost me doing a carbureted 6.0. Granted I would have ended up with a used junkyard motor in those situations instead of a new 401. Power would have been a little better though and for the cost of heads and intake on this motor later I could have rebuilt the bottom end of an ls.