Has anyone installed an LS in a 98 using factory electronics???

[awbrown]

I posted a few days ago about an exhaust problem I was having in trying to remove the 5.7 in my new 98 silverado .. i was just offered a 40k miles 5.3 and would love to avoid the expense of rebuilding the 5.7 .. Anyone ever swapped an LS into where a 5.7 resided ?? if it is not possible has anyone done it with an aftermarket system and still had the trans work properly?? thanks

[Tom]

Someone like blackbear might be able to tune the stock PCM with the LS data, otherwise it would be easiest to swap in an 0411 PCM and have them load the data onto that.

[awbrown]

Well ,I needed a driver rather fast so I had a rebuilt short block and a set of vortec heads , so I threw that together and replaced the engine .. it runs well and it is getting me around for the time being , but I plan on doing some more tuning to it to see if I can get it more responsive... maybe I will post some pics later ...

[UKNOWME]

We did one at our shop for the first time and it was a PITA. We did you the GM performance parts plug and play PCM and TCM but keeping all the guages and some other accessories was a little difficult.

[DANSBIRD]

We put a 5.3L in my dad's '90 Silverado.



http://lstwo.com/images/63506987422970057913.jpg


http://i.imgur.com/jIe41AG.jpg



First time she fired up w/ the new heartbeat:

https://www.youtube.com/watch?v=fW-qGYfrGGo


And on the dyno:

https://www.youtube.com/watch?v=lPYZpCaikBU



All of the gauges work fine. I can't remember if we kept the stock computer and also added the PCM for the 5.3L or got rid of the stock computer all together. Sorry I couldn't give any more info, but to answer your question, yes, it's quite possible.

[rickpilgrim]

My engine rebuilder guy put a 6.0 out of a wrecked 04 2500 in his 97 burban but he used the complete powertrain and electronics and wiring to do it.
As the owner of an 04 Z71 1500 suburban w/3.73 and just towing 2600 lb of trailer for 240 mi with the 5.3 in tow/haul mode, cruise set at 70 on a 60 degree calm day I can't see a 5.3 in any truck as it never hit 4th gear or less than 3100 rpm, average 9.7mpg and no reserve power.
I'd find and pay for a 6.0 before getting paid for taking a 5.3 for my truck

[DANSBIRD]

Originally Posted by rickpilgrim

My engine rebuilder guy put a 6.0 out of a wrecked 04 2500 in his 97 burban but he used the complete powertrain and electronics and wiring to do it.
As the owner of an 04 Z71 1500 suburban w/3.73 and just towing 2600 lb of trailer for 240 mi with the 5.3 in tow/haul mode, cruise set at 70 on a 60 degree calm day I can't see a 5.3 in any truck as it never hit 4th gear or less than 3100 rpm, average 9.7mpg and no reserve power.
I'd find and pay for a 6.0 before getting paid for taking a 5.3 for my truck

If he's not building a dedicated tow truck, then he will be fine. The 5.3L in our '90 Silverado does just fine and put down over 300hp to the wheel. Another local one put down 360 to the wheel. Plenty of power for any typical truck.

Besides, I'd venture to guess an '04 Z71 Suburban is going to weigh a little more than a '98 Silverado. Especially if it's a 2WD regular cab.

[rickpilgrim]

What I'm saying here is 2 things:

The best way to swap to an LS engine is to have the complete LS vehicle to start with. It's far less expensive that way and you'll have a lot of nickel and dime things. You still need mount adapters and trans stuff also so budget accordingly.

The 5.3 and the old 5.7 vortec have very different power curves, the LS is raw horsepower that starts to really respond at about 3-3500 rpm and the vortec 5.7 pulls hard starting around 2-2200 but runs out at 5000 rpm or so, where my 5.3 is still going strong. In a street race between my 98 K2500 reg cab 5.7 truck and my 5.3 04 Suburban it's all 98 to 50mph and all Suburban after that. Using my 427 ex cab 4x4 dually against Suburban it takes to 70 mph before the 5.3 has a clear advantage.

[awbrown]

Funny you folks bring up the horsepower issue between the LS and the 5.7 I did dyno this engine to break in the cam because the shortblock was a nonroller.. I had a shortblock and a set of vortec heads all rebuilt and sitting on the shelf ,and driving the 63 was not fun in the august heat .. I used a torque cam ,but should have advanced it 4 degrees ,just seems to lack a bit down low , or it could be I am just too used to the 7.4 I had in my other truck ,anyways I did dyno the stock 5.7 vortec engine with torque cam and it made 303 hp.. almost wish I had stuck with the stock cam or wish I had taken the time to degree it in ,but I had a small window to get it installed ...

[rickpilgrim]

The reason I brought horse power into this is that if your thinking about an LS swap to replace a sb chevy and what it takes to do it you should know all aspects of what the end result will be. A 5.3 LS engine has a different power curve than a 5.7 vortec sbc and also has different mounts, crankshaft length and in some cases requires a different oil pan. It uses vastly different engine management and wiring which brings the costs of doing this beyond a 5.7 rebuild.
Now in our little shop when we're spending more money than a mild performance rebuild for a customer they like a dollar based increase in driving feel and performance/economy and having owned and driven more than 5 5.3 vehicles I am not convinced the cost of doing this will be totally satisfying. For what an average LS swap costs and the work involved most who visit us go either 383 vortec or big block route as the 5.3 isn't better in stock form.