Have any of you guys thought about or have done a V8 swap ?

jwolfejt

jwolfejt

Caught the Bug
The Problem:

I have made my first round of my round trip 220 mile commute earlier this morning and I noticed that while it feels like I have more power than day 1 (it has about 5k miles on it now). It has to scream to maintain speed up some of the hills/grades that I am going up - downshifting to 5th at times and making passing at anything above 70mph commanding alot/all of pedal pressure. I don't really want to smoke the tires on demand (would be cool) - but I would like the ability to cruise effortlessly at 70mph and not have to worry about each hill I am about to pull, and to be able to pass safely within a reasonable space/timeframe. Maybe I was spoiled with the 6.7 Cummins - but man it never really needed to downshift (other than to save the trans from the TQ in the OD gears).



Elevation:

At elevation the Pentastars are adequate at best - I can't even imagine towing :(. If I was going to be near sea level all the time I don't think I'd really even bring this up.

Bigger Tires:

This cannot be a good experience on bigger tires - even after a regear - I can't imagine adding 40+ lbs to each tire and the added rolling resistance getting you back to stock-ish acceleration. Driving a JT on 40's (with 5.13 gears) you definitely feel the rolling resistance.

Options ?
V8 swap:

  • Hemi's seem to be the closest thing to plug and play. The only options i've seen is the AMW setup - which from my understanding a authorized center has to install.
  • Bruiser has a LT swap using modifications for Mopar sensors and a remapped PCM.
  • Anyone else ?
Supercharger really worth it ? Every case i've seen this done has resulted in catastrophic engine failure/damage.
 
Bierpower

Bierpower

Hooked
jwolfejt said:
The Problem:

I have made my first round of my round trip 220 mile commute earlier this morning and I noticed that while it feels like I have more power than day 1 (it has about 5k miles on it now). It has to scream to maintain speed up some of the hills/grades that I am going up - downshifting to 5th at times and making passing at anything above 70mph commanding alot/all of pedal pressure. I don't really want to smoke the tires on demand (would be cool) - but I would like the ability to cruise effortlessly at 70mph and not have to worry about each hill I am about to pull, and to be able to pass safely within a reasonable space/timeframe. Maybe I was spoiled with the 6.7 Cummins - but man it never really needed to downshift (other than to save the trans from the TQ in the OD gears).



Elevation:

At elevation the Pentastars are adequate at best - I can't even imagine towing :(. If I was going to be near sea level all the time I don't think I'd really even bring this up.

Bigger Tires:

This cannot be a good experience on bigger tires - even after a regear - I can't imagine adding 40+ lbs to each tire and the added rolling resistance getting you back to stock-ish acceleration. Driving a JT on 40's (with 5.13 gears) you definitely feel the rolling resistance.

Options ?
V8 swap:

  • Hemi's seem to be the closest thing to plug and play. The only options i've seen is the AMW setup - which from my understanding a authorized center has to install.
  • Bruiser has a LT swap using modifications for Mopar sensors and a remapped PCM.
  • Anyone else ?
Supercharger really worth it ? Every case i've seen this done has resulted in catastrophic engine failure/damage.
Click to expand...
Motech does the LT swap but they use the 10L80 instead of the factory transmission like bruiser. I've done two of them now. They have a pretty solid system.


Edit: like jeeeep said, I've done JK's and I know Motech did a gladiator/JL at some point but not sure they ever put a kit together for it.
 
wayoflife

wayoflife

Administrator
Staff member
Superchargers are a waste of money and if you got to any V8 swap shop, you'll see a bunch of them laying on pallets.

If you're considering LT, I would highly recommend Motech. They are who I'll be using when I can get around to doing one on my JT. I've seen their kit for the JL and driven it and while it's not 100% ready for sale, I'm sure it will be soon.

Also, added tire weight is far from a cause of power loss. Maybe if you do a lot of stop and go driving but an object in motion tends to stay in motion. Rolling resistance is real and that will hurt MPG. Tire diameter and the bigger you go will also be a factor as it in essence a final gear. Regearing WILL make a big difference but at best, it'll just bring you back to stock performance and as you've noted, it's nothing to write home about.
 
kevman65

kevman65

Hooked
When Jeep switched to the GPEC5 ECM they pretty much shut down the tuning market for power adders. No one has been able to crack the code(s) to be able to write to it.
 
jwolfejt

jwolfejt

Caught the Bug
wayoflife said:
Superchargers are a waste of money and if you got to any V8 swap shop, you'll see a bunch of them laying on pallets.

If you're considering LT, I would highly recommend Motech. They are who I'll be using when I can get around to doing one on my JT. I've seen their kit for the JL and driven it and while it's not 100% ready for sale, I'm sure it will be soon.

Also, added tire weight is far from a cause of power loss. Maybe if you do a lot of stop and go driving but an object in motion tends to stay in motion. Rolling resistance is real and that will hurt MPG. Tire diameter and the bigger you go will also be a factor as it in essence a final gear. Regearing WILL make a big difference but at best, it'll just bring you back to stock performance and as you've noted, it's nothing to write home about.
Click to expand...
Not sure what Motech's figures are - but was told to budget atleast $45k for a 392 swap. AMW will not even sell you a setup unless you are an authorized installer (so DIYers are SOL). Was told they maybe able to do a non MDS engine (I would in no way want a MDS hemi). If anyone was looking into doing the 5.7 swap - they do not do those anymore. 392 is the base option and it goes up from there. 45hrs is a installer base estimate and can exceed from there.

The thing i do not like about the newer GM stuff is the Direct Injection and the afm/displacement on demand junk. The 10 speed has also proven to be hit or miss in 1500's. If i want the GM route - i'd want a LS3 and would have to think about going 10 speed or something else (I think only the 8L is compatible with the LS3 PCM but could be wrong).
 
wayoflife

wayoflife

Administrator
Staff member
jwolfejt said:
The thing i do not like about the newer GM stuff is the Direct Injection and the afm/displacement on demand junk. The 10 speed has also proven to be hit or miss in 1500's. If i want the GM route - i'd want a LS3 and would have to think about going 10 speed or something else (I think only the 8L is compatible with the LS3 PCM but could be wrong).
Click to expand...
Having run both an LS and now an LT, I would only go LT and in part because of the direct injection. The AMF/displacement is junk but can be removed. I am running the 10 speed now and so far, I've been happy with it. But, that's just been my personal experience.

 
jwolfejt

jwolfejt

Caught the Bug
HighwayTrout said:
Yea. That’s a problem.

I’m all for a v8. But I’d rather buy a beater Toyota or Honda if I had a hellish commute like that.
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Did that - and burned through countless shitboxes, ford fiestas, chevy cruzes etc. I expense my mileage, fuel etc so not worried about that so much. Also in the great state of VA - they rape you for property tax on vehicles and I don't feel like paying $1500 additional a year (in property tax) on some piece of junk beater that will be falling apart after a year of usage (literally).

wayoflife said:
Yup, couldn't agree more. A Jeep of any kind would suck for a commute like that.
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It is most definitely not the most comfortable and I am at the tail end of needing to this commute for much longer.
 
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jwolfejt

jwolfejt

Caught the Bug
wayoflife said:
Having run both an LS and now an LT, I would only go LT and in part because of the direct injection. The AMF/displacement is junk but can be removed. I am running the 10 speed now and so far, I've been happy with it. But, that's just been my personal experience.

Click to expand...
The only other thing I've seen with the LT's is the intake valve/ports carbon build up - which is common with most/all DI engines and biggest reason why some manufactures now run both DI and port injection. I had this happen on a couple beater cars I was using (all were direct injected). The 10 speed issues were probably just isolated to the first 2 year or so runs.

So if i spend the better part of $50k on a powertrain swap, another $35k or so later on down the line on axles, suspension (which is really easy to do) Jeep itself was $47k OTD. Or I can buy a bigger truck for all the truck stuff and commuting and just go as crazy with suspension stuff/axles on my JT and not really worry about passing power (can literally buy a whole new 1 ton truck for a little more than what the swap costs). It all adds up scary fast.
 
JT@623

JT@623

Hooked
I’ve got the LT1 10 speed in my JK if I were to swap my JT Motech would be the place I would go. They’ve got it figured out and they haven’t forgotten the customer service aspect of what they do.
 
jasont0311

jasont0311

Caught the Bug
I’ve had the 6.4 on my JT for a few months now. I did the AMW conversion and so far it’s definitely been a plug and play transplant with no major issue so far. It was definitely a want and not a need and you should account that these things are THIRSTY. Granted I’m still on 5.13’s with my Dana 44. That will be changing next week, I’m stepping down to 4.88’s with the new axles and hoping that will help but lets be honest, it will be minimal at best. Running around town and cruising on the highway is a blast and you don’t feel anything towing. I never felt the 3.6 was that bad, sure she would downshift like crazy but we still got to where we were going, even towing a small camper. If Motech was a little closer they definitely would have been on my radar for a LS swap. Again, this was a want not a need for my mid life crisis build. I’ll be doing the exact same trails I did with a 3.6 just with a bigger smile on my face…Unless I start to overheat
 
jwolfejt

jwolfejt

Caught the Bug
jasont0311 said:
I’ve had the 6.4 on my JT for a few months now. I did the AMW conversion and so far it’s definitely been a plug and play transplant with no major issue so far. It was definitely a want and not a need and you should account that these things are THIRSTY. Granted I’m still on 5.13’s with my Dana 44. That will be changing next week, I’m stepping down to 4.88’s with the new axles and hoping that will help but lets be honest, it will be minimal at best. Running around town and cruising on the highway is a blast and you don’t feel anything towing. I never felt the 3.6 was that bad, sure she would downshift like crazy but we still got to where we were going, even towing a small camper. If Motech was a little closer they definitely would have been on my radar for a LS swap. Again, this was a want not a need for my mid life crisis build. I’ll be doing the exact same trails I did with a 3.6 just with a bigger smile on my face…Unless I start to overheat
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Same - not a want but a need.
 
jwolfejt

jwolfejt

Caught the Bug
TrailHunter said:
Was thinking the same thing on my way down to your post.
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Only way I am getting another vehicle is if its a Harley lowrider st is a bit enticing - but a touring bike would make more sense for that kind of riding. Or if i really need a 1 ton truck (key word being need).
Brute said:
It sounds like you need another vehicle with a V8 in it already…
Click to expand...
I love me a V8 (partial to chevy v8s - the hemi's are cool but really love the LS engines and older small block chevys). There aren't many options with v8 vehicles that are comfortable - there is the charger, and the 1/2 ton trucks (which i want nothing to do with - mds/afm garbage mainly and in the ford's case the wet belt driven oil pump). The best way to get a v8 nowadays is to go for a 1 ton truck with the 7.3 ford imo - no afm/mds crap, no direct injection - just a big v8 with port injection (it does have VVT though). I had one of those and it averaged 13mpg (probably not far off from what a 392 swapped JT would get).
 
Ddays

Ddays

Hooked
Call me crazy, but unless you're a military contractor with an open expense acct why would you want to spend the dough on fuel for a daily 220 mile commute with anything other than a throw away commuter dog? That works out to well over 200k miles in a year. Assuming 25 mpg, $3/gallon thats $24k in fuel costs. In your Jeep its gonna be at least twice that.

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Now if it's not a daily thats a different story
 
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