Which Engine?

[Grumpyroger]

I need some input from you Guru's out there! Let me start by saying Thank You in advance for any help you might offer.

I have a 1969 C-20, I acquired from a Gentleman down the street about 10 years ago, it was in really rough condition, and I am still working on it. It came with a 350 CI engine, TH400 trans and 4.10 gears. Seeing that the truck is 43 years old and still runs good (I tow a 23' travel trailer with it) I know it will be due soon for an engine rebuild. (Trans done last year) I want to set it up for a good amount of Torque, should I just built a Stroker 383 or should I change it out for a BB 454 or something.
I have remove all of the smog (not required) and I want to replace the TH400 with a 700R4 Trans. What do you think?

I also have problems towing the trailer up hills, and that's the reason I need more power and torque. Any Ideas?

[buckskins4ever]

If you are really planning on towing your trailer a lot more with it....I say go with a 454BB. You will gain the torque for pulling and keep up horsepower. Plus you will savemoney on this route. A true well build 383 Stroker would run you over $5k here.

[jhwkns]

A good running 350/400 with a 4.10 gear should tow that just fine.

[FLDBRED]

There really is nothing like a BB for torque, but remember you'll have to change other things to get it in there. A 383 with the right cam and combo would get the job done and be a simpler swap.If you only tow occasionally go 383, if it's a routine thing go BB and never look back!

[brad_man_72]

There's a reason people are throwing ls based engines in everything th.at moves.
My 5.3 gets 17mpg going 70mph pulling my boat.
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[PanelDeland]

Swapping to a BB gets you power but at a price.BB engines are getting pricey and the accessories may be as much as a core.The LS is great choice but will require some electrical mods.An AOD will need to be built to tow(I woulf think the 4L80E might be OK stock).I would look for a late model to rob a LS and AOD out of.Get the whole vehicle if you can so you have all the little buts you'll need(they can add up to big$$$)then scrap the rest.I would also look for the larger displacement LS at least a 6.0.

[Grumpyroger]

Thanks everyone, I will take all these opinions under consideration, and go from there.....Grumpy

[CC69Rat]

Running cones, overall power vs. economy vs. total cost of the swap I'd choose an LS based iron block swap.

Pulling a trailer 23ft long up hills, I'd choose a smaller ci BB. As others have said, Big Blocks are tough to beat for torque. Yes, you can get power out of an LS motor too and I'm giving credit to all the LS guys out there.. (I'm looking at a swap too) But for what I have in my 408ci BBC, I couldn't have paid for the LS conversion.

Good and bad in both really but in your situation I'd lean more toward a BBC.

[Hawssie]

I wouldn't put a 700r4 behind a big block, I know people do and I know they can be built up, but the best bet is a 4L80e. Its basically a turbo 400/w an overdrive. If you get a 1991 up 454 drivetrain it will come with a 4l80e(assuming its an automatic truck) The easiest swap is the 1991-1995 454 throttle body version. They aren't really high in the horsepower but it would be a clean easy swap with minimal smog and electronics, They are super reliable, probably the most reliable drivetrain GM ever made. More reliable then new fuel injected trucks(with the OBD2 smog, four 02 sensors etc) or old carburetor engines. Easy to work on and parts are cheap. Run it without the Cat, and they tow great but need a good radiator. You can pick these up pretty cheap. The 1990s trucks over here with big blocks sell terrible. i passed up on 1998 crew cab 4x4 with a 454 and A LT with leather for $2600. I sold a 1989 regular cab 2wd truck w/ fuel injected gen 4 454 w/ turbo 400 last year for 500 bucks. My buddy sold his 1999 regular cab 1 ton utility truck with a 454 last month for $1300. Thats all he or I could get. Maybe its just the BAY AREA CA. but a gasser big block is a curse for resale unless its a classic truck. When gas over here cost over $4 a gal... You must be used to revving at 2500 rpms or more going down the freeway without an overdrive and 4.10s. Its a great towing setup but terrible on gas mileage. I bet when your going 65 (the speed limit) on the freeway and you take your foot off the gas its almost like putting on the brakes. Thats how that 89 I sold was. It had 4.10s as well. People who test drove it couldn't believe it. I told them up until the early 90s just about every 8 lug truck GM and everyone else sold drove just like that. Because none of them had an overdrive!

[MARKDTN]

Originally Posted by Hawssie

I wouldn't put a 700r4 behind a big block, I know people do and I know they can be built up, but the best bet is a 4L80e. Its basically a turbo 400/w an overdrive. If you get a 1991 up 454 drivetrain it will come with a 4l80e(assuming its an automatic truck) The easiest swap is the 1991-1995 454 throttle body version. They aren't really high in the horsepower but it would be a clean easy swap with minimal smog and electronics, They are super reliable, probably the most reliable drivetrain GM ever made. More reliable then new fuel injected trucks(with the OBD2 smog, four 02 sensors etc) or old carburetor engines. Easy to work on and parts are cheap. Run it without the Cat, and they tow great but need a good radiator. You can pick these up pretty cheap. The 1990s trucks over here with big blocks sell terrible. i passed up on 1998 crew cab 4x4 with a 454 and A LT with leather for $2600. I sold a 1989 regular cab 2wd truck w/ fuel injected gen 4 454 w/ turbo 400 last year for 500 bucks. My buddy sold his 1999 regular cab 1 ton utility truck with a 454 last month for $1300. Thats all he or I could get. Maybe its just the BAY AREA CA. but a gasser big block is a curse for resale unless its a classic truck. When gas over here cost over $4 a gal... You must be used to revving at 2500 rpms or more going down the freeway without an overdrive and 4.10s. Its a great towing setup but terrible on gas mileage. I bet when your going 65 (the speed limit) on the freeway and you take your foot off the gas its almost like putting on the brakes. Thats how that 89 I sold was. It had 4.10s as well. People who test drove it couldn't believe it. I told them up until the early 90s just about every 8 lug truck GM and everyone else sold drove just like that. Because none of them had an overdrive!

If you don't want to go LS, this makes a lot of sense. I am not a fan of BB power. You can get most of what you need with a fuel injected small-block. But if I were to do any kind of swap tomorrow it would definitely be LS power.

[Z10]

Here's what I'm doing.

ZZ4 crate motor. 355hp and 405ftlb of torque and a 700r4.

Should do the trick.