Author Topic: A 5.3L swap?  (Read 36006 times)

Offline Skunksmash

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A 5.3L swap?
« on: April 28, 2010, 03:46:36 AM »
Hi all just wanted to stop by and pick the brains of a few of you guys who have done the 5.3L swap in one of the 73-87 chevy trucks. Instead of trying to rebuild a TBI motor to the specifications that I need, I have found out that my goal would be easier reached by using a more modern engine. I like a lot of aspects about the 5.3, and after searching here and a few other places, it seems like a bunch of people have done this swap. So I would like to ask, what all is involved?

Is it a huge expense, or a major pain in the rump?

What do you perceive would be the advantages of having a 5.3L over an older motor? (other than the fact that I hate carborators with a passion)

What year year/model should I get the 5.3 out of?

How do you make all the little things work? Like cruise and the gauges and stuff.

Those are just a few of the questions I have about the swap. I imagine that somewhere probly sells the motor mounts an major components by now..

Offline VileZambonie

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Re: A 5.3L swap?
« Reply #1 on: April 28, 2010, 05:02:37 AM »
If you get a good deal on one and can handle doing it yourself it can be a worthwhile swap. The advantages are for stock to stock comparisson increased torque and fuel mileage. Although it's not leaps and bounds so again unless you get a really good deal the advantages won't really be seen in your wallet with the expense of the swap. A lot of people like to do it simply for the modern appeal and potential upgrades you can do to the LS engine. Anything you need for the swap is available for our trucks including adapters for the motor mounts.

Vortec heads are still a popular inexpensive upgrade for the 5.7L and TBI systems can be plucked from a donor rather inexpensive if your goal is inexpensive efi.
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Offline slammed79

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Re: A 5.3L swap?
« Reply #2 on: April 28, 2010, 01:47:55 PM »
The sweet thing with the 5.3 swap is that most of them will take a LS6 cam and net a 100 hp increase. If you dig through Car Craft tech the dyno numbers are there, and that was with a carb if I remember right. The LS6 intake is good for some additional hp if you stay with the injection. These engines are basically destroked LS1's and pick up easy horsepower.

I'd reccomend finding a 99-03 engine, I can't remember the code off hand, but those are readily available complete from intake to pan for about a grand.
« Last Edit: April 28, 2010, 01:49:50 PM by slammed79 »
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Offline Stewart G Griffin

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Re: A 5.3L swap?
« Reply #3 on: April 28, 2010, 03:44:03 PM »
What is the weight difference between an ls and a sbc?

Offline Skunksmash

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Re: A 5.3L swap?
« Reply #4 on: April 28, 2010, 06:15:43 PM »
Well I am looking to pick up some gas mileage over my wore out 5.7L that only gets 14MPG. Some of the trucks that the 5.3L came out of weighed more than my truck, and got around 18MPG. At least according to a few people on my other forums. My current engine is on it's way out, so I figure if I'm going to have to replace it, I may as well replace it with something good.

Also, I was hoping to find a lower mileage engine out of an '08 model truck, so that I don't have to rebuild it before I slap it in there. Basically I'm just looking for something that gets decent mileage, and won't break my wallet when towing a little boat or a couple jet-ski's to the lake.

Offline Skunksmash

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Re: A 5.3L swap?
« Reply #5 on: May 03, 2010, 05:11:37 PM »
Been researching it a little more, it seems like people tend to stay away from the 08 and 09 engines due to a greater difficulty in the swap.

Offline Captkaos

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Re: A 5.3L swap?
« Reply #6 on: May 03, 2010, 11:57:16 PM »
They were Displacment on demand and electronic throttle, which added to the complexity, but you can still use them, and if you can make them work you will benefit from the DOD for mileage.  Most people that you are reading about are after power not economy.

Offline Skunksmash

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Re: A 5.3L swap?
« Reply #7 on: May 05, 2010, 07:37:41 PM »
Hmm, never heard of displacement on demand. Sounds weird though. Like it somehow changes the displacement of the motor. Which I always thought required a new crank

Offline SUX2BU99

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Re: A 5.3L swap?
« Reply #8 on: May 06, 2010, 10:29:41 AM »
No I think the usual way it works is it cuts the spark and fuel to 1/2 the cylinders when cruising. My 05 Magnum R/T had it too on the 5.7 HEMI.  And so did my aunt's 81 Cadillac with the infamous 4-6-8 V8 motor  :D Those were notorious for not working well but hey, it was 1981 technology! I remember watching the little onboard computer display say when it was firing on either 4, 6 or 8 cylinders. Without port fuel injection, I think the only thing it did was cut spark to the cylinders. I could be wrong though. The modern DOD systems I believe only switch between 4 and 8 cylinders.
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Offline Layne

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Re: A 5.3L swap?
« Reply #9 on: May 06, 2010, 04:33:24 PM »
I think it actuated a solenoid on the rocker arm so it wouldn't open. I'm thinking opposite of V-TECH?
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Offline team39763

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Re: A 5.3L swap?
« Reply #10 on: May 06, 2010, 08:57:31 PM »
I think another problem with the 08+ motors is the VVT.  I think it involves going into the motor to deactivate it(change lifters).  If I could do my swap over again, I'd go with the 08+ motor(L92,L76,LS3).  The additional power is well worth the trouble to me.  I don't know any easy solutions to the DOD or electric throttle.  Since mine is a performance application, I'd probably swap on a Edelbrock intake and 4 barrel throttlebody with a LS2 ECM or something.

Offline Skunksmash

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Re: A 5.3L swap?
« Reply #11 on: May 06, 2010, 10:05:14 PM »
I don't think I want a solution to it if it gives me better gas mileage. I'll get my power gains out of a set of long tubes and a full exhaust, as well as a few other mods that don't adversely affect mileage. But which is the most desireable '08/'09 5.3L engine? It seems that there are actually a few variations...

Offline team39763

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Re: A 5.3L swap?
« Reply #12 on: May 07, 2010, 01:32:43 PM »
I don't know much about the 08+ 5.3's, but if I had a choice, I'd get the one with the aluminum block.  Other than that, I'm not too sure on the differences between the motors(besides one or two being E85 compatible).  I think I remember reading that the DOD technology really isn't that great on these motors yet...like GM still has a long way to go before it's useful.  I think I remember a member on this site saying his work truck had DOD and the only time it went into 4cyl mode was coasting down a hill, so it really never saved him any gas.  I do know you can always get a good tune and help improve the gas mileage though.

Offline Captkaos

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Re: A 5.3L swap?
« Reply #13 on: May 10, 2010, 05:17:08 PM »
Yeah the VVT also adds to the complexity.  If you are going to run it like it is you won't have any problems, but there are solutions to everything if you throw enough time and money at it.  LOL

Offline choptop

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Re: A 5.3L swap?
« Reply #14 on: May 10, 2010, 07:30:10 PM »
My work truck is an 08 with the 5.3 DOD, and it doesnt seem to have anymore power or fuel economy than the 04 it replaced. Both trucks were 4x4, and both trucks carried the same load. i think the DOD is a waste
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