engine question....
 

ok guys ive been thinking for a while now and i dont think i want to put my 350 back in my truck. i want to go with a newer fuel injected engine. how are the 5.3l's in general? is there any newer v6's that get ok mileage and still have decent power? please throw out some suggestions if you have any. i dont need monster power but i want decent power.
thanks guys,
John

Re: engine question....
 

Ya 4.3's do ok but not sure what it would do fuel mileage wise in our kinda trucks :lol:

Not sure on the 5.3's im curious also.. That would be a nice upgrade

Re: engine question....
 

There's another thread here about a 5.3 swap. You oughta check that out.

Why not a 350 by the way?

Re: engine question....
 

I have a 4.3 in my 92 GMC ex cab long bed. It gets about the same gas mileage as my 03 blazer with a 4.3 and I know that the blazer gets about 24 highway and 18 city.

Re: engine question....
 

well theres a few reasons i dont want a 350. firstly everybody and there dog runs a 350. second being gas mileage. third being id rather put my money into a newer fuel injected setup than spend the money on a rebuild right now. because carbs are great but fuel injection is more dependable. ive seen a few 50,000 mile 5.3's for around $500 complete, so you just cant beat that. lol
thanks guys,
John

Re: engine question....
 

I'm in the middle of trying to get my 5.3 wiring harness set up correctly. Alot of the good gas economy comes from the 4l60e trasmission behind the motor, the od helps alot. I'll post some pictures and a step by step for the harness once I get it all figured out, but that won't be for a few months. Here is some info for the wiring harness:
http://www.lt1swap.com/2000harness.htm

I'll keep a running tally of what the cost was for this swap
Engine and trans $1000 craigslist
Alternator $100
Wiring harness $150 craigslist
PCM(computer) $50 ebay

Re: engine question....
 

I'd bet you could get just as good mpg from a properly set up SBC and a 700r4 trans. Wiring would be much simpler, and there would be no computer to mess with. MHO

Re: engine question....
 

I was looking at the same thing. The best combo I found was the 2008 Cadillac 3.6L direct injection engine (LLT) out of a STS or CTS. It has 302Hp and 272 lb.-ft. of torque, is mated to the 6l50 6-speed transmission, and uses regular unleaded gas. The STS weights 4000 Lbs and gets a real world 18/27 MPG with a 3:42 rear end.

Here is the GM blurb on the engine.

I found one in a bone yard for $3000 complete with anything need for the swap but sadly, I could not find anyone that can do the computer (remove VATS, etc) so I am looking at the 5.3L LSx motor as it has been done and there is a lot more vendor assistance available.

Re: engine question....
 

I would suggest a 4.8, they have almost the same power output as a 5.3 but are much cheaper, but similiar to as the above post without an OD and fairly economic rear gear then your not gonna get impressive MPG......i would steer clear of a V6
-G.Lester

Re: engine question....
 

The GenIII/LSx engines are probably the best bet. Everything in the design is more modern and was actually designed in an era where fuel economy mattered. As was stated, the 4.8 (LR4) is good (what I'm probably going to use in my burb) because design wise, it's nearly the same as the truck 5.3 and still makes very respectable power compared to a GenI SB.

The other option (as a 6 cylinder guy) is the Vortec 4200 inline 6. It's possible, but the electrical is a bit more problematic compared to the LSx. Don't blow the Atlas engine off, as the stock 4200 makes 275 hp (with modern HP ratings). I really doubt many near stock 350s are going to make that kind of power in the real world. Incidentally, these numbers blow the old 4.3 V6 (350 minus 2 cyls) out of the water.

The last, truly key thing is an overdrive transmission and proper rear end gearing. For ideas, I'd look at the current Chevy trucks including the Canyon for ratios and tire sizes. If you've got the engine from a current truck, you should be able to come close on mileage if the gearing is setup right, especially considering our old trucks are very likely lighter than the current ones.

Good luck, whichever way you decide to go.

Re: engine question....
 

If you want to be differant, Diesel power! how about a 12 valve cummins with a 9 speed behind it. should make more power than you can ever use and have enough torque to pull your house down the street. it will fit under the hood, and it will be the only one in town. If you set it up right, you can get 25+ mpg out of it and have the option of running home made biodiesel....about .56 cent a gallon.

Re: engine question....
 

Words from a true truck driver... how's it going Derric?

This would definitely be an economical option if you have a source for WVO and the ability of making biodiesel. I have given this some thought as well since I have a source for all the WVO I would need.

For a gas engine I would go with the 5.3....it seems to be a popular swap these days and fairly easy to get a hold of conversion parts for. Since you can get one for $500 I'd go that route....that's a good deal.

Re: engine question....
 

Doing well, how have you been?

Re: engine question....
 

thanks for all the help guys!! ill need to think more but i will probably go for eaither the 5.3 or the cummins. only problem with the cummins is the cost of the swap, but that kinda power would be awesome!! lol
thanks again,
John

Re: engine question....
 

Hewlett,

I have been working on small block chevy's since I was a kid but I am working on a 6 litre LS3 motor swap for my 65. I don't ever want to work on the old engines again. The new motors are really well engineered.

I am planning on getting 20+ mpg with the 6.0 motor and T56 - 6 speed with 3.73 rear. I have a 6.2 litre LS3 that rolled into the garage today with 24.6 mpg average back and forth to work. (That's the best I can squeeze out of it) But it runs 21 mpg average when I drive normal.

TR

Re: engine question....
 

how expensive are the LS3 engines to pick up used?

Re: engine question....
 

Another Cummins option some folks aren't aware of is the 4BT (the 12V used in the earlier Dodge trucks was the 6BT). The 4BT is the 12V minus two cylinders.

For 1/2 ton trucks, this engine is lighter and still makes tons of torque. I've thought of using one in my 77, but there are a number of unknowns and the cost is likely to be pretty high. Check this Google search for all the 4BT swap info out there:

http://www.google.ca/search?q=cummin...ap&hl=en&meta=

Some guys running these are getting over 30 mpg and I've even heard of 40 mpg.

Re: engine question....
 

Doin' ok myself Derric....thanks!

Re: engine question....
 

The diesel option isnt limited to a cummins, how about a 4 popper, turbo charged, super charged, 2 stroke detriot diesel? theres no sound like a 2 stroke detriot grabbin gears and blowin smoke! ggggrrrrrrrrrrr pop! ggggrrrrrrrr pop! ggggrrrrrrrrrrr! bangin gears, turnin heads and scaring children!

Re: engine question....
 

Or how about a white continental multifuel? anyone got to much kerosene or that coleman stove fuel? they claimed they would run on cheap whiskey. Or maybe the old DT466 IH. relativly small and turbo charged, loud and throaty sounding. Any of these swaps could be had for around $500 if you shop around abit and know where to look.

Re: engine question....
 

well just looking at prices, i can do the 5.3l swap and do it the way i want for about $1000. so thats what im going for. but im spending my money on rebuilding the front end first. like ive said before im no good and suspension work. my buddy dropped by in his 66 LWB fleet 305/powerglide. im gonna tell ya, ive never rode in a 60-66 that rode that smooth, so im gonna do exactly what he did, and he said he would help. he ended up spending about $900 on new suspension front and rear, dropped a couple inches. after that ill move on to the engine. and its a 99.9% chance im going for the 5.3l . so i have one more question... what tranny should i use? 700r4? im not up to date on the newer transmissions so if theres one out there that would be better then please let me know.
thanks again for all the help, dont know what i would do without you guys!!!
John

Re: engine question....
 

My vote is for a row-yer-own 5 speed, like s nv3500 or nv4500. If your thinking more automatic, go with a 4L80E. Its a big tought th400 with overdrive. perfect match for the 5.3

Re: engine question....
 

My 5.3 in my 2000 Silverado gets 20 mpg on the highway, but could probably do slightly better if tuned and driven easy.

Re: engine question....
 

Im Doing a 5.3/NV4500 swap and its defintitely not an option for $1000... Even to get find a cheap nv4500 you're looking at probably $750, plus whatever you spend on the engine. Then you may have to change out your front crossmember or figure out your own mounts... exhaust....even the little stuff like getting p/s and a/c hooked up its all$$$... If you do the swap with an automatic go for the 4l80e its the best automatic gm makes other than the allison 6 speed auto that comes in the hd pickups...good luck with the swap its definitely the way to go!:metal: