So as always 2.5ls r slow right. I want 2 do a swap at some point but what LS, mag V8 ???? So with that said if I go one way or another I know my ax5 needs 2 go do I get a ax15 ??? Transfer case as well right. Will my drive shaft b right yet same splins idk ??? Or do I need everything???? So lost right now its not even funny. Someone help answer this stuff lol. Right how I have 31s with a 3.5 lift 5th gear well we don't do 5th gear that's a no fly zone
Questions and advice about swapping a V8 into my 2.5 TJ
- Thread starter Brandon2001tj
- Start date
How much are you prepared to spend. To do this right is going to cost you around 15-25k depending on various options.
The AX5 would not be the ideal candidate for a V8 swap. Prolly want to upgrade your Dana 35 in the rear if you are looking for above 35s or a V8. You do not need a different transfer case. You wrote, "Will my drive shaft b right yet same splins idk ??? Or do I need everything???" This is difficult to understand.
To answer alot of your questions you need to ask yourself questions. What are you doing with the Jeep? What tire size your looking for? There are alot of variables to look at. Gearing a 2.5 makes it just as capable as any on the trail. Just dont weigh it down with useless crap.
To answer alot of your questions you need to ask yourself questions. What are you doing with the Jeep? What tire size your looking for? There are alot of variables to look at. Gearing a 2.5 makes it just as capable as any on the trail. Just dont weigh it down with useless crap.
Stock your 2.5 came with 4.10 gears in the axles and 27-28" tall tires so by going to 31" tires you have changed the gearing on your rig. You need to swap to 4.56 gears or 4.88 to regain your stock type power. I ran 4.88 gears with 33" tires and could use 5th gear again some of the time. So before you decide to do an engine swap also think about regearing your axles.
Now for doing a V-8 swap there is a LOT of things to consider. You have basically 3 options for a V-8 swap.
1) Dodge magnum V-8 used in Dodge trucks from 1996-2002 and Grand Cherokees 1993-1998
2) Dodge Hemi V-8
3) Chevy LS type V-8
Here is a 190 page thread on the Jeepforum about doing the Dodge/Jeep magnum V-8 swap.
https://tinyurl.com/n8cdjeh7
If you want to do a V-8 swap your best choice is to find a complete vehicle and buy it to use the parts you need.
Using a GC for the magnum swap if you keep the automatic trans puts the starter on the passenger side where as if you use Dodge V-8 it puts the starter on the drivers side.
There are threads on on here and other Jeep sites about doing the Hemi or Chevy V-8.
If you want to keep your manual transmission then you will need a AX-15 trans and a 92-94 Dodge Dakota V-6 bellhousing to use it.
You will also need to either change the input gear on your transfer case from a 21 spline to a 23 spline or get a transfer case from a 4.0 Jeep. Or depending on the vehicle you use for the swap you could use the transfer case from it.
Now for doing a V-8 swap there is a LOT of things to consider. You have basically 3 options for a V-8 swap.
1) Dodge magnum V-8 used in Dodge trucks from 1996-2002 and Grand Cherokees 1993-1998
2) Dodge Hemi V-8
3) Chevy LS type V-8
Here is a 190 page thread on the Jeepforum about doing the Dodge/Jeep magnum V-8 swap.
https://tinyurl.com/n8cdjeh7
If you want to do a V-8 swap your best choice is to find a complete vehicle and buy it to use the parts you need.
Using a GC for the magnum swap if you keep the automatic trans puts the starter on the passenger side where as if you use Dodge V-8 it puts the starter on the drivers side.
There are threads on on here and other Jeep sites about doing the Hemi or Chevy V-8.
If you want to keep your manual transmission then you will need a AX-15 trans and a 92-94 Dodge Dakota V-6 bellhousing to use it.
You will also need to either change the input gear on your transfer case from a 21 spline to a 23 spline or get a transfer case from a 4.0 Jeep. Or depending on the vehicle you use for the swap you could use the transfer case from it.
I've got to go to an appointment with the VA. I'll post more information when I get home this afternoon.
Christoph
Member
As a disclaimer I haven't finished the swap yet. I'm still in the middle of buying parts and continuing to research. It's a lot to learn.
If you want a shortcut without doing a lot of reading here is what I personally found to be a consensus on multiple forums. Get a GM engine, specifically the LM7 5.3L. It has a the aftermarket support you'll need and is the most commonly swapped engine in TJs with tons of builds/questions/info online.
I'm going the automatic route and didn't do any reading on the AX15, but I would venture to guess it will still push everything back and you will still have to change both front/rear drive shaft lengths. I would also HIGHLY recommend changing out the Dana 35 rear axle you have as suggested above to a Dana 44, ford 8.8, etc. Maybe you can get by without it, I was planning on keeping mine, but found out it was shot anyway and after doing more reading was glad I wasn't allowed to use it. If your Jeep plans on seeing the trail I would advise you do yourself the favor of dumping that Dana 35. Plenty to read on axles/gearing alone.
If you're serious about doing the swap get ready to spend some money. I'm budgeting for around $15k and that's me doing everything except changing the shaft in the transmission to match my transfer case splines. I'll end up doing a writeup on costs when I'm done.
A short build list and not AT ALL exhaustive:
Lastly, if money isn't an issue you can get a turnkey engine from companies like BD Turnkey, ready to swap axles from ECGS, or you can really blow your wad on a crate engine. It's all up to you at that point and what you're trying to accomplish. Best of luck. It's been fun for me so far and I haven't regretted taking the leap yet, but my wallet fucking HATES me.
If you want a shortcut without doing a lot of reading here is what I personally found to be a consensus on multiple forums. Get a GM engine, specifically the LM7 5.3L. It has a the aftermarket support you'll need and is the most commonly swapped engine in TJs with tons of builds/questions/info online.
I'm going the automatic route and didn't do any reading on the AX15, but I would venture to guess it will still push everything back and you will still have to change both front/rear drive shaft lengths. I would also HIGHLY recommend changing out the Dana 35 rear axle you have as suggested above to a Dana 44, ford 8.8, etc. Maybe you can get by without it, I was planning on keeping mine, but found out it was shot anyway and after doing more reading was glad I wasn't allowed to use it. If your Jeep plans on seeing the trail I would advise you do yourself the favor of dumping that Dana 35. Plenty to read on axles/gearing alone.
If you're serious about doing the swap get ready to spend some money. I'm budgeting for around $15k and that's me doing everything except changing the shaft in the transmission to match my transfer case splines. I'll end up doing a writeup on costs when I'm done.
A short build list and not AT ALL exhaustive:
- Dana 44 and Dana 30 axles (Craigslist)
- 5.3 LM7 w/ 4l60e trans (Craigslist)
- -Including wiring harness, ECM, pedal assembly etc.
- Trans adapter to TC
- Short SYE to TC
- Engine/Trans mounts
- Radiator/Trans cooler
- Front/Rear Drive Shafts
- Custom cat back exhaust (local shop)
- Another 10-100 things I can't think of right now
Lastly, if money isn't an issue you can get a turnkey engine from companies like BD Turnkey, ready to swap axles from ECGS, or you can really blow your wad on a crate engine. It's all up to you at that point and what you're trying to accomplish. Best of luck. It's been fun for me so far and I haven't regretted taking the leap yet, but my wallet fucking HATES me.
A cheaper route is to go old school with a small block Chevy like a 327. HP and torque on the low end are better than the 4.0 and on the high end get into the 370HP range.
You can customize based on your wallet. Run it with a fuel pressure regulator or new pump, carburetor, and HEI distributor. Or add throttle body injection if you want to tune it. Then figure out what to do with your gauges. New rebuilt complete motors are in the $3000 to $4000 range. But used should be cheaper. You'll need a Novak adapter and I'd look for a TJ LSD Dana 44. The axles seem to be common around here as people upgrade.
If you skip the electronics it's easier and cheaper. You can add throttle body injection to gain power and tunability later. I run across CJs with carbureted small block chevy and Ford V8 conversions all the time. They'll outperform the 4.0 inline 6.
You can customize based on your wallet. Run it with a fuel pressure regulator or new pump, carburetor, and HEI distributor. Or add throttle body injection if you want to tune it. Then figure out what to do with your gauges. New rebuilt complete motors are in the $3000 to $4000 range. But used should be cheaper. You'll need a Novak adapter and I'd look for a TJ LSD Dana 44. The axles seem to be common around here as people upgrade.
If you skip the electronics it's easier and cheaper. You can add throttle body injection to gain power and tunability later. I run across CJs with carbureted small block chevy and Ford V8 conversions all the time. They'll outperform the 4.0 inline 6.
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The old school sbc option is a good choice InOmaha mentioned, the issue can be if it has emissions to be street driven. I went that route when i installed the 406 small block in the last yj i had (wasnt worried about emissions then).
Around here a ls 6.0 with wiring, computer and pedal are going for around 22-2500 and have less than 150k on them, still need a transmission, t-case adaptor, cooling and mounts etc so it can add up quickly.
Around here a ls 6.0 with wiring, computer and pedal are going for around 22-2500 and have less than 150k on them, still need a transmission, t-case adaptor, cooling and mounts etc so it can add up quickly.
Even if you don't have emissions testing where you live by federal regulations it is still illegal to swap an older engine into your vehicle.
Cost wise the Dodge magnum V-8 is the cheapest route. Yes the power isn't as good as a Chevy engine but it's still the least expensive route.
A 5.2 or 5.9 engine are normally easy to find and not that expensive.
The wiring is fairly easy and because the PCM for the V-8 can talk to your dash you don't need new gauges.
Cost wise the Dodge magnum V-8 is the cheapest route. Yes the power isn't as good as a Chevy engine but it's still the least expensive route.
A 5.2 or 5.9 engine are normally easy to find and not that expensive.
The wiring is fairly easy and because the PCM for the V-8 can talk to your dash you don't need new gauges.
Nope. Congress wrote those laws to keep us from pulling out a cleaner engine and replacing it with older, less clean technology engine (in theory). Not mentioned is that you also have to keep the emissions equipment from the newer engine as well - that‘s the real kicker.
But you are right - that‘s our government for you.
Wow thanks everyone so much ill start with re gearing 1st and then see where I end up going u guys r the awesome
They should encourage recycling. It's not like this stuff will last forever anyway. Other than some garage queens things will eventually disappear.
Driving an older vehicle saves material mining, production, and manufacturing energy. Most people need to get 3 or 4 times the gas mileage of a TJ or old truck just to try to come ahead on price difference. They never will if they borrow money.
If we all put old "dirty" diesels in, we'd burn a lot less fuel and dump cars less often. It's why I don't like government policies. They aren't based on detailed analysis and thought.
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