Getting serious about engine swap

[Tony13393]

I’m getting serious about finding my engine and transmission for the swap on my 06 tj.

I’ve done a bit of research and I believe I want a:

2007 lm7 Chevy 350
Nv4500 5 speed manual transmission

Can I get some thoughts on my choices and potentially some help on the first steps in finding these items.

Thanks

 

[Apparition]

I’d go auto. Then again I have an LS3 and 6L80 on order.

 

[hardtailpan]

Yours is a good candidate for a 5.7 hemi swap. Your jeep has the correct higher pressure fuel pump (05/06 only), you can retain the NVLD so it can be emission legal, the gauges communicate via PCI bus which can talk directly to a hemi computer. If you have a Dana 44 in the rear, even better. If it were me I'd go this route. Which transmission is a harder choice. The auto swaps are reasonably well documented, the manual choices are a little tougher. I was eyeballing using a AX15/NV3550 behind a 5.7 hemi, tho either of these are likely a bit underrated for hemi hp/torque numbers.

 

[Tony13393]

Yours is a good candidate for a 5.7 hemi swap. Your jeep has the correct higher pressure fuel pump (05/06 only), you can retain the NVLD so it can be emission legal, the gauges communicate via PCI bus which can talk directly to a hemi computer. If you have a Dana 44 in the rear, even better. If it were me I'd go this route. Which transmission is a harder choice. The auto swaps are reasonably well documented, the manual choices are a little tougher. I was eyeballing using a AX15/NV3550 behind a 5.7 hemi, tho either of these are likely a bit underrated for hemi hp/torque numbers.

I think your right about the transmissions you looking at. I don’t know that they would hold up with your hemi.
My rear end is a Ford 8.8 with 4:10 gears and limited slip. It was my last project. We welded the tubes to get ready for the engine swap

 

[hardtailpan]

Yup, if I were you I'd definitely go hemi then! Easy and smart to go with the auto out of whatever donor truck you use 545rfe or something like that. I'm still collecting parts, but I may try to use one of the medium duty transmissions I mentioned above. They are supposedly rated at about 300hp,but in something like a 7000lb vehicle (at least the nv3550). I don't do any heavy wheeling or rock crawling, so I'm thinking as long as I don't go dropping the clutch on pavement, it should last fairly well. Also, I will run the hemi bone stock.

The other manual transmissions that are good for this swap are simply hard to fit into a TJ due to their size. some people have done it with body lifts and tunnel mods, but I'd rather not go down that path.

 

[Woodrow]

Why the NV4500? I have one in a 1994 GMC K3500 that I use as a fire truck. It can be adapted to the NP 231 and its fairly beefy, but its long, heavy and although a 5-speed, really its a 4 speed (1st is a creeper). Its also expensive to buy/rebuild. The AX-15 and NV3550 are said to do well with moderate V-8s and might fit better in your jeep.

 

[Tony13393]

Well I wanted to cam out the lm7 to around 400 hp and thought it to be a good idea to have the beefier transmission. I understood that a small body lift would get it in there. I put a 2” old man emu heavy spring lift in it,which actually brought it up about 6”. The old suspensions was really shot I guess…
But that was my rationale

 

[Tony13393]

Now you all have me researching hemi s! Lol

 

[Apparition]

Now you all have me researching hemi s! Lol

Check @NashvilleTJ build thread for hemi stuff

 

[Tony13393]

I’d go auto. Then again I have an LS3 and 6L80 on order.

I just found a guy building ls3 with 6l80 trans he asks 8750.00 turnkey engine with radiator etc… how’s that sound?

 

[TRE3TOP]

No way in hell I’d do a hemi over an LS.

^ doesn’t sound like that bad of a deal. LS3 is a badass engine

 

[hardtailpan]

No way in hell I’d do a hemi over an LS.

^ doesn’t sound like that bad of a deal. LS3 is a badass engine

I don't understand why? The Hemi is a cleaner fit in many ways for the TJ being a Mopar mill and in many cases makes the swap easier (same computer bus for example). Plus all the pieces exist to make it 50 state smog compliant (NVLD). Maybe that's possible with the LS, but from what I've read it is not.
Drawbacks of the hemi are primarily price, which admittedly is a big one as its a lot more expensive, and lack of aftermarket support.

The LS is certainly an excellent option and the swap of choice for almost everything these days. Cheap, plentiful, huge knowledge base, and plenty of aftermarket support.

I'd consider either, but I'd lean toward the hemi because i like the idea its from the same manufacturer, and I like the cool factor of it. I've always hated seeing the Ford hot rods with Chevy 350 engines.

As far as performance, either is a huge step up.

Now, if your reason is that "you're not a mopar guy" well, there's not much left to say at that point, it's like arguing the existence of God.

 

[TRE3TOP]

The LS is a much better engine than a hemi IMO. And you pretty much summed it up with it being way cheaper, and much more support and knowledge. There’s a reason LS engines are dropped into damn near anything and hemi are pretty much only put in mopars.

I don’t live in a smog compliant state nor do I plan on it so that really isn’t a factor for me. If I lived in California, well I may have a different viewpoint.

 

[hardtailpan]

The LS is a much better engine than a hemi IMO. And you pretty much summed it up with it being way cheaper, and much more support and knowledge. There’s a reason LS engines are dropped into damn near anything and hemi are pretty much only put in mopars.

I don’t live in a smog compliant state nor do I plan on it so that really isn’t a factor for me. If I lived in California, well I may have a different viewpoint.

Yeah, if its a cost thing, I get it.

The Hemi does have some issues such as dropping valve seats, but it is a reasonably solid platform.
As for California, I don't think anything but electric vehicles are going to be legal there in a few years anyway.
And I think the reason the LS motors are put in almost everything comes down to the first point again: cost (and availability)

 

[NashvilleTJ]

I don't understand why? The Hemi is a cleaner fit in many ways for the TJ being a Mopar mill and in many cases makes the swap easier (same computer bus for example). Plus all the pieces exist to make it 50 state smog compliant (NVLD). Maybe that's possible with the LS, but from what I've read it is not.
Drawbacks of the hemi are primarily price, which admittedly is a big one as its a lot more expensive, and lack of aftermarket support.

The LS is certainly an excellent option and the swap of choice for almost everything these days. Cheap, plentiful, huge knowledge base, and plenty of aftermarket support.

I'd consider either, but I'd lean toward the hemi because i like the idea its from the same manufacturer, and I like the cool factor of it. I've always hated seeing the Ford hot rods with Chevy 350 engines.

As far as performance, either is a huge step up.

Now, if your reason is that "you're not a mopar guy" well, there's not much left to say at that point, it's like arguing the existence of God.

Great summary. I live in an emissions required area, and as I’ve always understood it in many places in order for a swap to be compliant the engine cannot be older than the original, and it also has to have been offered in the product line at some point. Since the Hemi was offered in the Grand Cherokee, it qualifies (again, my understanding - hopefully to be corrected if wrong).

Far from a bolt-in, the Hemi is a marginally easier swap into a TJ compared to an LS. But yeah, more expensive, less aftermarket support, and challenging to fine a good tuner.

I’m a Mopar guy from way back - so there is that.

But the real reason I went with the big Hemi was that I have a life long hatred of spark plug wires.

 

[Wildman]

Great summary. I live in an emissions required area, and as I’ve always understood it in many places in order for a swap to be compliant the engine cannot be older than the original, and it also has to have been offered in the product line at some point. Since the Hemi was offered in the Grand Cherokee, it qualifies (again, my understanding - hopefully to be corrected if wrong).

Far from a bolt-in, the Hemi is a marginally easier swap into a TJ compared to an LS. But yeah, more expensive, less aftermarket support, and challenging to fine a good tuner.

I’m a Mopar guy from way back - so there is that.

But the real reason I went with the big Hemi was that I have a life long hatred of spark plug wires.

This subject seems to come up at least once a month is not more. Swapping an engine into a Jeep NOW isn't like it was in the 60's and 70's that is for sure.
It doesn't matter where you live technically if you swap a engine into a newer vehicle by federal EPA rules the engine has to be from the same year or newer. So you can't take a 1987 Chevy 350 and drop it into a 1997 TJ legally but as most know no one is gunna be checking unless you live some place that has emissions testing.

@Apparition check out this video. They talk about using the Jeep 3.8 V-6 stuff on their LS.

And then Gen 4 Hemi vs GM engines.

I'm like Nash in I'm a Mopar guy and I find doing a Dodge/Mopar swap into our TJ's things are just easier hands down. But as pointed out a GM power plant is cheaper and easier to get more power out of. Yep this has been the story since the 1950's and I think will always be the case. BUT when you start adding the additional money you have to spend to make the GM stuff work in our TJ's it evens out a little.

 

[NDSpeed]

I want to ditto the transmission thing, I bought al the parts needed for the hemi conversion, figured I would have a few winters in Alaska to knock it out. I bought a five speed manual from the dodge trucks. That tranny is a monster. (Think Bruce Jenner wearing a Dress) no way was it fitting.

So now my Jeep is Diesel, and the 55 F100 is getting a hemi with a 5 spd

 

[Tony13393]

Great summary. I live in an emissions required area, and as I’ve always understood it in many places in order for a swap to be compliant the engine cannot be older than the original, and it also has to have been offered in the product line at some point. Since the Hemi was offered in the Grand Cherokee, it qualifies (again, my understanding - hopefully to be corrected if wrong).

Far from a bolt-in, the Hemi is a marginally easier swap into a TJ compared to an LS. But yeah, more expensive, less aftermarket support, and challenging to fine a good tuner.

I’m a Mopar guy from way back - so there is that.

But the real reason I went with the big Hemi was that I have a life long hatred of spark plug wires.

I live in a no emission area

 

[Wildman]

I live in a no emission area

Yes BUT say you do a non-emissions legal swap and then in 3-10 years from now they passed emissions testing where you live???
Now you have a vehicle you can't register or license any longer. IMO it's just crazy now days NOT to keep your vehicle emissions legal.
I don't have emissions testing where I live but I still installed the O2 sensors and cat to keep it legal.

 

[Jamison C]

Yes BUT say you do a non-emissions legal swap and then in 3-10 years from now they passed emissions testing where you live???
Now you have a vehicle you can't register or license any longer. IMO it's just crazy now days NOT to keep your vehicle emissions legal.
I don't have emissions testing where I live but I still installed the O2 sensors and cat to keep it legal.

Or if you ever go to sell the vehicle. We have no emissions up north but if I wanted to swap in a V8 and then later down the road end up trying to sell it to someone in Phoenix, it would have to pass smog because they have emissions in Maricopa County.