Re: My swap. 5.3 into a 1990 3/4 ton 4x4 Suburban.
 

Cooool. Have you got any gas mileage #'s yet? A friend has a very similar 'Burb with the stock TBI 350 and is considering a ls swap. -Thanks, Brian

Re: My swap. 5.3 into a 1990 3/4 ton 4x4 Suburban.
 

I'm curious about the gas mileage also. I've got '72 3/4 big block burb that I'm considering this swap on. It is my daily driver and the 7-10 mpg is killing me. I wanted to keep the th400 that I already have, but there aren't many numbers posted on Mileage with that tranny. Most people swap the new tranny in. I'm thinking the th400 would hold up better and be cheaper to replace or fix if it does break down. If I could eventually get a gear vendors unit it would be even better!!! So please post your mileage when possible!
Thanks!!
Shawn

Re: My swap. 5.3 into a 1990 3/4 ton 4x4 Suburban.
 

Im not too sure yet. Im doing a few things to it before i get it on the road. Im really doing all the stuff to it now that i would have done if i never would have had to mess with the motor! So, it still needs new tags before i start cruising it around. Im thinking the first of the month i will start driving it a bunch.

Honestly, im expecting my my milage to go from about 10 average to about 13 average. I dont think it will be a big jump for me but i guess im just keeping my standards low so that im not dissappointed.

Re: My swap. 5.3 into a 1990 3/4 ton 4x4 Suburban.
 

I mostly did this swap (believe it or not) because i couldnt get my damn tbi 350 to idle right! I rebuilt it and did everything in the world short of pulling it and rebuilding it again trying to get it to idle right. Fought with it for 5 years and 10,000 miles and could never figure it out. So, i finally said F it! I wanted the 5.3 anyway so i figured it ought to solve my stupid idle problem without having to chuck another dime at that stupid 350! There was just so many times with the 350 where i would put it to the floor and think, "really? thats all i get?" The fact that the 350 came from the factory with less then 200 HP, there was no way i was going to keep spending money on something that was grossly sub par to begin with. So, for me, more then anything the biggest reason for the swap was the bad idle on my 350. Add to that that i gained 100hp and 35 ft.lb of torque and a couple MPG, and i was sold.

Re: My swap. 5.3 into a 1990 3/4 ton 4x4 Suburban.
 

Heck 13mpg compared to 10 would be a 30% increase. Like you said 100 more hp and better fuel economy seems like a no brainer. Nice work.

Re: My swap. 5.3 into a 1990 3/4 ton 4x4 Suburban.
 

Thanks!

Re: My swap. 5.3 into a 1990 3/4 ton 4x4 Suburban.
 

Going back through this thread, i realize i left out a couple pics.

This is what i did for the steam line thing,

http://i597.photobucket.com/albums/t...i/IMAG0614.jpg

This is a few pics of how the intake came out.

http://i597.photobucket.com/albums/t...IMAG0604-1.jpg

http://i597.photobucket.com/albums/t...IMAG0603-1.jpg

http://i597.photobucket.com/albums/t...i/IMAG0611.jpg

http://i597.photobucket.com/albums/t...i/IMAG0608.jpg

And a couple crappy pics of the current little project of mounting the computer. If i would have started off with a truck wiring harness i would have just mounted the computer on the inner fender like the factory. With the option to mount it under the dash, i figured i might as well. So, there just aint no way your going to mount this computer where the orginal one sat. At least not without modifying the heck out of the glove box. So, it kinda fell into place right where the air recirculation door is. So thats where im putting it! Covering the couple inches that hang down with the factory flapper door diaphragm cover. Got a little bit to go on it still. But just to give you an idea.

http://i597.photobucket.com/albums/t...i/IMAG0623.jpg

http://i597.photobucket.com/albums/t...i/IMAG0627.jpg

Re: My swap. 5.3 into a 1990 3/4 ton 4x4 Suburban.
 

Looking good!
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Re: My swap. 5.3 into a 1990 3/4 ton 4x4 Suburban.
 

Looks real nice!
My only concern with installing these engines in older trucks is the cam torque curve. I have a 2000 with a 5.3/4l60E/3.73 gears running 285/75x16 tires. It gets better mileage at 80 than at 65-70 mph. I heard that GM lowered the operating rpm range in the 6.0 engines cams in 2011. Does anybody know about this? BTW by better mileage I mean 17.75 to 18.13 mpg on Interstate 15 through Utah on my way to Wyoming. It normally gets about 2 to 3 less mpg when going 65-70. Actually am considering a 4.10 gear swap to get better mileage...or maybe the 6.0 cam if it runs at a lower rpm range.
I have to admit that before considering a big block or diesel engine swap I would definitely consider this swap before anything else in an older vehicle.

Re: My swap. 5.3 into a 1990 3/4 ton 4x4 Suburban.
 

My thougts are that if they work in a 2002 suburban, they will work in my 1990 suburban.

Re: My swap. 5.3 into a 1990 3/4 ton 4x4 Suburban.
 

Got it registered and insured! Took it for its first real test drive! All was well except the sloppy steering that it had forever. Definite power difference over the TBI 350! I will say though that it does seem to have slightly less low end torque but much more high end hp! All in all its definitely a well rounded perfectly useable power.

Re: My swap. 5.3 into a 1990 3/4 ton 4x4 Suburban.
 

Here's a preliminary 0-60.

http://i597.photobucket.com/albums/t..._VIDEO0118.jpg

Re: My swap. 5.3 into a 1990 3/4 ton 4x4 Suburban.
 

Very nice. I would love to see your mpg numbers when you get them. My Big Block is getting an abysmal 6.5 mpg city and 9 mpg highway. I need to figure out something to do soon.
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Re: My swap. 5.3 into a 1990 3/4 ton 4x4 Suburban.
 

The sucky thing is with the way gas prices is, it will be a while before i can actually FILL my tank in one sitting... At 37 gallons or whatever my tank is and $4.00 a gallon, thats about $150! I just cant stomach that. I can pay the $20 a week but cant do the fill ups!

Re: My swap. 5.3 into a 1990 3/4 ton 4x4 Suburban.
 

Thats a very nice swap. I am still debating one of these or diesel....prolly diesel since I live in the peoples republik of kalifornia

Re: My swap. 5.3 into a 1990 3/4 ton 4x4 Suburban.
 

how well did the stock 5.3 intake assembly go in where the battery would be... i guess at least that's where mine was because i plan on doing a heck of a lot of mudding and cold air isn't really a good setup and i don't like the filter sitting right off the intake i just like a stock look

Re: My swap. 5.3 into a 1990 3/4 ton 4x4 Suburban.
 

It was a cake walk! Two simple brackets off the stock battery tray and i was in business! Its not a "cold air" intake any more and just gets its air from that corner of the engine compartment but i feel its pretty safe from debris unless i did a lot of mudding.

Re: My swap. 5.3 into a 1990 3/4 ton 4x4 Suburban.
 

Kick ass thread, Brother! Considering the same swap for my shortbed.

I was actually considering a 6.0 for my '88 K20 Sub. Now that you've driven it for a while, what are your thoughts? If you had to do it all over again, would you go 6.0 or keep the 5.3?

Re: My swap. 5.3 into a 1990 3/4 ton 4x4 Suburban.
 

Thats still hard question to answer. Reason being is im still running my 5.3 on a 571 LS1 tune! IT runs surprisingly well on it but it overfuels a decent amount at WOT and before the o2 sensors are warmed up and it goes into closed loop mode. I think its safe to say that the size of my wallet determines how i feel about 5.3 vs. 6.0 on any given day. As well, the amount of "work" that my truck does is taken into consideration. If i worked my truck harder, i would say it needs a 6.0. If i had more money up front and didn't care about mileage, i would go 6.0. But for me, less money up front, plus less money at the pump, plus only moderate towing, added up to a 5.3 being the right choice for me. I think that once i get a 5.3 tune in the computer and make it a 5.3 "performance tune", i will be more than satisfied with the power. On the flip side, if i had it my way, i would do a 6.0 with the zo6 cam, headers, and a dyno tune. That would be awesome!

Re: My swap. 5.3 into a 1990 3/4 ton 4x4 Suburban.
 

On a side note, for those that havent seen, I just got the truck painted so im pretty excited about that!

http://i597.photobucket.com/albums/t...i/SAM_2222.jpg

Re: My swap. 5.3 into a 1990 3/4 ton 4x4 Suburban.
 

Looks great! Dig that color.

Re: My swap. 5.3 into a 1990 3/4 ton 4x4 Suburban.
 

Have you had an opportunity to get any MPG figures yet? Curious to see the numbers with that TH400.

Re: My swap. 5.3 into a 1990 3/4 ton 4x4 Suburban.
 

About 12 mised driving. The problem with my numbers are that as i said, the computer is tuned wrong and my trip to work (which is most of my miles i put on my trucks...) is a whole 4 miles round trip... So, it doesnt even get to operating temp normally! I expect that when its all dialed in and if given the chance to drive normal miles it would be right at 15 as a running average. So not that great, but a bump up from the 10 it used to get!

Re: My swap. 5.3 into a 1990 3/4 ton 4x4 Suburban.
 

http://i597.photobucket.com/albums/t...229_142009.jpg

Got my reprogrammed computer today! Can't wait to see what it does for my mpg and power!
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Re: My swap. 5.3 into a 1990 3/4 ton 4x4 Suburban.
 

Very nice build! Update on mileage and power with reprogrammed ECM?

Re: My swap. 5.3 into a 1990 3/4 ton 4x4 Suburban.
 

No... Sadly there is quite a challenge getting a properly programmed computer for this truck. The problem being, im using a camaro harness and o2 sensors. This doesnt jive well with the 5.3 (truck) tuning. Ultimately, right now, im running a 5.3 tune and its nut reading the o2 sensors... So, my power seems about the same as with the LS1 tune, and my milage seems better. But i actually havent driven it much since i got it done, had it re painted, and got my 2012 Sierra. My long/short term plan is to rip the wiring all back out and start back from scratch using a combination of the ls1 harness and a normal truck harness. In doing so i will b e switching back to the truck o2's as well. There is a big list of hindsight issues at play here. So, it will be a while before i start driving it with any degree of consistency again, but when i do, i;ll report. Honestly tho, i feel that the 5.3 in a burb is pushing it. Its plenty of power, but its not got a lot of excess power. I think a 5.3 with a good tune, headers, and CAI is plenty well sufficient. I think if i had it all to do over, i probably wouldnt have done anything different. Its just the situation i was/am in. The old motor was so bad that it wouldnt have made it to where it is now. And i just really like everything about having a LS under the hood! But, In the end, the 5.3 wont stay in here forever. Its a place holder until i drop in a 6.0/6.2/8.1.

Bottom line, I would do a 5.3 swap into anything in a heart beat! THey just run good! They are cheap(ish) reliable, and just fun!

Re: My swap. 5.3 into a 1990 3/4 ton 4x4 Suburban.
 

question: i didn't think the harness would make much of a difference, as long as everything plugs in (DBY or Cable and etc...). I agree the O2's will change the tune a little. I'd recommend (rockauto.com) to get a cheap set of o2's for the 5.3.

Re: My swap. 5.3 into a 1990 3/4 ton 4x4 Suburban.
 

Lol that wasn't a question. The problem is the Camaro o2s are case grounded qwhile the truck o2s are grounded through the ecm. So the computer is just flat out not reading them.
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Re: My swap. 5.3 into a 1990 3/4 ton 4x4 Suburban.
 

sorry if i came off ignorant, i should have phrased it more as a question than a comment. Is it a possibility to ground the O2's through the ecm by adding pins in the right spot of the ecm plugs?

Re: My swap. 5.3 into a 1990 3/4 ton 4x4 Suburban.
 

Maybe. Truthfully though, im just not interested in that. I want to take it back to being a little more simple. I dont want so much mix and matching. I want to mostly, completely rewire the whole engine instal to make it a lot more factory as opposed to how i just tied it all in like i did the first go around. It would probably work forever if i went back with the LS1 tune and kept the wiring just how it is and had a tuner custom tune the fuel/spark maps. But thats just not quite what i want. I want it to be a 1990 suburban with a factory 5.3. If that makes any sense.

Re: My swap. 5.3 into a 1990 3/4 ton 4x4 Suburban.
 

You did an excellent job on your swap. Did you ever get a tune sorted out? Any more pictures of how you mounted the stock air intake box?

Re: My swap. 5.3 into a 1990 3/4 ton 4x4 Suburban.
 

Yes i did. In the end it was a simple matter of running the 5.3 tune and re wiring the o2 sensors. Now tho, I have ripped my wiring all back out and am in the process of re doing that. Here is where im at now!

http://i597.photobucket.com/albums/t...psgfbvqyqx.jpg

Re: My swap. 5.3 into a 1990 3/4 ton 4x4 Suburban.
 

Very nice! Sucks to go back and redo it tho I bet.

Re: My swap. 5.3 into a 1990 3/4 ton 4x4 Suburban.
 

Very nice work on the new harness! It will definitely be worth all the trouble for piece of mind.

Re: My swap. 5.3 into a 1990 3/4 ton 4x4 Suburban.
 

Kinda. But i feel like I knew this was coming. When i bought the motor i wasnt very happy about the harness. But i was so excited to have it and get it up and running that i just went ahead and installed it. The more i lived with it, the more it ate at me knowing that i was driving around a hack job. The tags (registration) went bad while i had it down for paint so i figured i would just leave them bad and start fixing some of the stuff that i put off when i was just to eager to drive it.

Might not look like much in the pics but it is turning out really good. I have done one before and learned alot from it on what i wanted out of this harness. And most importantly, just zero hack. Im 100% confidant in this harness! :metal:

Re: My swap. 5.3 into a 1990 3/4 ton 4x4 Suburban.
 

During,

http://i597.photobucket.com/albums/t...ps9a9kkwtf.jpg

http://i597.photobucket.com/albums/t...psxk5kth3q.jpg


Pile of unneeded wire from the harness,

http://i597.photobucket.com/albums/t...pstvlljzbv.jpg

Re: My swap. 5.3 into a 1990 3/4 ton 4x4 Suburban.
 

I hope to channel your patience when I tackle my wiring. I am hoping b/c I am going to integrate the entire wiring harness from my 2001 donor I won't have that big pile of "spaghetti" wiring! Looking good though, patience pays off in the long run as well as having and doing the right stuff!

Re: My swap. 5.3 into a 1990 3/4 ton 4x4 Suburban.
 

Now the real fun begins. Turning all this into something that looks pretty.


http://i597.photobucket.com/albums/t...psqfqfm1ww.jpg

Re: My swap. 5.3 into a 1990 3/4 ton 4x4 Suburban.
 

Looks like all thats left is to loom it up!

Re: My swap. 5.3 into a 1990 3/4 ton 4x4 Suburban.
 

Pretty much. I still have to make up the fuse block in the cab and route everything just right. This week leading into Memorial day I'm pretty busy so I will probably hardly touch it until next week.