383/700R4 or Explore LS Swap for my 70 SWB

[Nohassle5]

Hey Guys, Having a bit of an internal dilemma. I have to start off by saying, I’m not the wrench, but know enough to be dangerous. When we built this truck to keep the costs reasonable, I left the basic 327 and TH400 in place as it was completely functional and ran fine. We put AC, nice headers and a polished front runner kit to finish it out. While it won’t set your hair on fire, it cruises fine.
Now that the build is done and operational, I’m wanting a little more response out of my right foot. I’m considering a Smeding 383 E series motor producing 420hp and a phoenix 700R4 OD tranny to mate to it. This is going to bring me up to about 8K in costs + Installation and gotchas. Seems like a fairly bullet proof option and reliable. Any reason I should explore an LS Swap option as I’m essentially just writing a check to get this done? There just seems to be so many pitfalls to getting them running and hooked up. Thoughts?

[Nitis]

IF I didnt have a 4x4 I would be doing an LS myself period. As for the pitfalls you speak of maybe you need a different shop? The people who have done them sure make it sound easy. Sure there may be some minor fab work here or there but the end result is amazing driveability

IF youre looking at $8k just for your power plant you can get a freshly rebuilt 6.0 from LSX4u for about 6 I think and a 4l80e shouldnt be rediculously pricey and should stay under budget.

And thats if you go for broke on a 6.0. If you were to go budget mided you could probably get one slapped in for about $4K installed if you went with a used setup

I just want to get in and drive sounds like you do to so go LS

[leftybass209]

If you are already set on replacing the motor and have a budget in mind, the LS is by far a better deal. When you consider the longevity of the motor, on top of the drivability and power, there is no comparison between Gen I or II motors and LS motors. I think LS motors are very bland when you look at them, but for double the total mileage out of one compare to a SBC, there's no justifiable reason to spend the same money for less of a return on your investment.

[Nohassle5]

Thanks for the replies. I've only got 700 miles on my build and I guess the beauty of the 383/700R4 is that it's all brand new. I have the beautiful Vintage Air Front runner, working AC, Ceramic Coated headers, polished valve covers, and air cleaner period correct look that I'm having trouble getting passed. I've got a 6.2 in my daily driver, and I've never gotten over 13 mpg in that thing. Diablo tune in it, and it's difficult to keep my foot out of it that's sure fun to drive. The builder has done multiple LS swaps, but not in a C10.

[leftybass209]

It's hard to justify a swap financially if everything is running correctly. A 327 can be built to scream, of course, also hitting you in the wallet. I also don't mean to throw another wrench in the works, but are you set on a 700r4? I have one and love it, but the 2004r has a little different gearing that may compliment your engine better. You also don't have to do the engine and tranny together. You can swap a trans in to see if that cures your itch for the time being. Depending on your rear gears (700's like 3:42's and higher) You may get a bigger seat of the pants feel by swapping rear gears in preparation for an OD trans.

[MAC71]

I have pondered this myself but decided to stick with the 1st gen engine. Its a 355 world SR toquer heads mild cam 600 CFM carb, 700R4 and 3.73 gears and I get 17 MPG at 70 MPH. I plan to change to a 3.55 gear and Fast 2.0 fuel injection later.

[Heavymetl]

LS for sure.

At this point, in 2015, it shouldn't even be a "debate" if starting from scratch as you are planning in doing.

Better driveability, wide power band, smooth, fuel mileage, throttle response, no leaks, easy cold starts, and if modded at all, WAY more power.

If you're new to the LS world, you'll probably think everyone is full of crap when it comes to power claims. I remember being where you are now and browsing LS1tech forums and seeing all these 346c.i., pump gas, full weight F-Bodies running 120+mph and low 11's/high 10's and thinking it HAD to be a lie, since the old school SBC just couldn't do that without MAJOR work. Well, it wasn't and it isn't. They are literally worth 100 more horsepower mod for mod over the old school.

Stock, an LS based engine is "meh". Let them breathe and throw in a cam...and it comes to life in a hurry.