IMO I wouldn't. The 5.7 Vortec is big and heavy. If you can get it to fit without cutting a hole in your hood or contacting your suspension components, it's still an old school iron block 350. The power gains are minimal, especially when you consider how much work it's going to take to swap it in. As far as I know, there are no aftermarket swap kits/support for putting them in a JK/JKU; It will be entirely custom work, including the wiring (you'll probably need to run aftermarket gauges).

If you're set on engine swapping, I'd look for any LS you can find in a junk/salvage yard (5.3, 6.0, 6.2). Pull the engine, and save up your money for the swap parts. You can swap it yourself if you have time, willpower, and some know-how. Mo-tech has been doing it for years and now makes what is essentially a DIY kit with the engine mounts and a plug-n-play harness, so it takes away a lot of the tedious work. Not to mention any LSx will put out much more power, even in stock form, than a built 5.7 Vortec. Ideally I'd get an aluminum block, but the power gains with the LSx motors will make an iron block (like the 5.3) worth it too.

I know it's tempting, but it's not as simple as you think it'll be. Save your $ for now, do it once, and be happy.

 

Pretty much what I expected to hear. Oh well. Wish it had been a Viper instead of a Subie. Thanks so much!

 

To be emissions compliant in CA you would need to use an engine from your Jeeps model year or newer. You'll need to retain all of the factory emissions systems from the Jeep and install the factory emissions systems from the donor vehicle. You will be hard pressed to have a street legal vehicle that will pass smog without using a kit such as Motech. I'm waiting on Mo-Tech to release the new Gen V kit with the MoCan, I'll likely sell my 2 door, and find a hi mileage 4 door preferably not running to build with the LS.

 

If I may have an opinion.
I am from South Africa and have imported a 1997 Vortec 5.7L.
I have done the conversion myself and it took me 4 days to install and start this motor with 4L60e transmission. Nothing wrong with the conversion and it is very easy ad I did not cut any hood or anything accept for new motor mounts and adapted transmission mount. Propshafts were done and whala all good. No need to run aftermarket cluster as all I did was keeping the original Jeep cluster, fitted the Jeep reluctor wheel on my crank balancer fitted the Jeep original crank sensor for signal to Jeep ECU used the Jeep motor harnas for the temp and oil pressure and again whala all good

 

If I may have an opinion.
I am from South Africa and have imported a 1997 Vortec 5.7L.
I have done the conversion myself and it took me 4 days to install and start this motor with 4L60e transmission. Nothing wrong with the conversion and it is very easy ad I did not cut any hood or anything accept for new motor mounts and adapted transmission mount. Propshafts were done and whala all good. No need to run aftermarket cluster as all I did was keeping the original Jeep cluster, fitted the Jeep reluctor wheel on my crank balancer fitted the Jeep original crank sensor for signal to Jeep ECU used the Jeep motor harnas for the temp and oil pressure and again whala all good

 

More A/C Information.

Discharge LIne (From Compressor to Condensor, front left of the engine bay)

Instead of using the Cold Hose Connection, I decided to use the stock 07 5.7 Dodge RAM discharge line. For some people it might work without any modification, but I had to convert it over to use the AN fitting . I didn't use the Cold Hose Fitting because I needed the sensor port. I'm fairly certain its a 10mm sensor port. I had difficulty finding one. I added the extra fitting in the middle because I cut it to short and needed some length.. I'm fairly certain its not really necessary. The AN fitting on the condensor is a 45 degree bend Reduced barrier #8.

Discharge line