Looking for Opinions - V8 Swap

[Trigger]

I've got Pater's old YJ and am looking to increase the power by swapping in a V8. Those of you that have done it, what would you recommend. I want to be fuel injected and I want a reliable motor, that has decent power. I don't need 500+ HP, but I would like it to be healthy. Some thoughts that have come to mind are 5.0L Ford, 5.3L Chevy, 6.0L Chevy truck and LS motors. Plans are for an auto tranny and an Atlas transfer case. Pros, cons, experiences? Budget is an issue, so I'm not looking to spend a ton of money, but I know that it's going to cost me some. Let me know what you guys think.

[TomH]

Gen-III 6.0L - Check
Auto - Check
Atlas - Check

Lots of support, lots of options, easy, great $/hp, always fires and runs, would do it again in a heartbeat.

[KargoMaster]

I'm using a 5.0L.... aftermarket support is pretty good but getting some age on the overall platform, so I would suspect that the 5.3/6.0/LS motors will be all the rage very soon... 4.6 modular??

Booo hiss on the auto tranny, but I might just be the last one driving a stick in the world... the way things are going, I have limired choices now, but I will not have any choice soon...

Atlas/STaK sounds like the most expensive part... but you get what you pay for... IMO


My last truck was 5.3 and 4L60e... I'm rough on things... Reaction sun shell went bye-bye at 116k... just for perspective. I was about 24 hours from pulling the driveline for my jeep (like Tom said... they're reliable) and parting the truck if it didn't sell, of course it sold then...

just my $.02

[Hope Springs Hauler]

There is too much support for the 5.3-6.0 motors to ignore them. I would also go with a TH350 or 400 if you don't need OD.

Personally, I would think seriously about a 4.0 based stroker. I've seen your jeep go a lot of places like it is, but a bit more oomph wouldn't hurt.

[94Dodge Truggy]

New generation 425 hp hemi! Depending on the wheeling you do you may want to make sure it will keep oil pressure at many different angles. A 5.9 dodge motor is hearty and I know where one is cheap and complete. The less sensors and ease of troubleshooting is key for trail motors. Titan sells a 4.7 I-6 for under $2500 with a warranty. Will the 6 cyl. in your jeep ever give up?

[itbrokeagain]

Keep the I-6 and stroke it. The V-8 isnt a bad thing but the 6 cyl is in it works and its wset up to be there. The V-8 swap takes some set up to get it all right. Sometimes I wish I had kept the 4.2. Never gave me any trouble.

[Trigger]

Will the 6 cyl. in your jeep ever give up?

It hasn't given up yet. Oil pressure is still low, but it still fires right up. The Jeep does pretty well for the motor that's in it. I just had some trouble the last time I was out and guys with bigger HP were able to power through some stuff that I got stuck on. It's a rarity that I can't do something, but when I went to really romp on it, it was lacking.

[94Dodge Truggy]

Stick a blue bottle on it and use sparingly. :evilgrin:

Let me know when you use it beforehand though so I can get my catchers mit out for the shrapnel. :beers:

[BIGRAM]

I'm fond of MOPOWER. Do the the Dodge thang!!

[KennyTJ]

HEMI..... HEMI..... HEMI..... HEMI..... well you get the point!!!! :D

[Trigger]

Stick a blue bottle on it and use sparingly. :evilgrin:

Let me know when you use it beforehand though so I can get my catchers mit out for the shrapnel. :beers:
I tell you what. When I'm ready for the swap, if someone has a blue bottle and wants to hook it up to the 6 cylinder, I will put on a show.:beers:

[blazerbrad]

An old TBI 350 Chevy is dirt simple to install and cheap. Add a few mods to it and pretty easy to decent HP out of them. A guy here at work pulled a Vortec 350 long-block out of the junkyard, slapped on a Vortec to TBI manifold, hooked up a couple of wires and off he went. No fuel system mods, no computer mods, etc... I'm sure it wasn't "tuned" to run optimally but it ran well and was strong.

It was a strong engine (250 HP), at least by real world standards......and substantially stronger than a stock 4.0L. Speaking of "real world", I think most people way over-estimate what their engine actually produces, or what you need (or can actually use) on the trail.

[sarge]

I tell you what. When I'm ready for the swap, if someone has a blue bottle and wants to hook it up to the 6 cylinder, I will put on a show.:beers:


Hehehehe I think I can hook you up :evilgrin:

[humpy]

An old TBI 350 Chevy is dirt simple to install and cheap. Add a few mods to it and pretty easy to decent HP out of them. A guy here at work pulled a Vortec 350 long-block out of the junkyard, slapped on a Vortec to TBI manifold, hooked up a couple of wires and off he went. No fuel system mods, no computer mods, etc... I'm sure it wasn't "tuned" to run optimally but it ran well and was strong.

It was a strong engine (250 HP), at least by real world standards......and substantially stronger than a stock 4.0L. Speaking of "real world", I think most people way over-estimate what their engine actually produces, or what you need (or can actually use) on the trail.

i would go vortec 4.3 b4 i messed with a tbi 350...very close in hp and the 4.3 weighs less and is smaller and easier to install in tight places... just my .02 i hate tbi 350 engines and i am a gm person since i was a kid...the tbi 350 was the sorriest excuse for a v8 gm ever put out...

[blazerbrad]

i would go vortec 4.3 b4 i messed with a tbi 350...very close in hp and the 4.3 weighs less and is smaller and easier to install in tight places... just my .02 i hate tbi 350 engines and i am a gm person since i was a kid...the tbi 350 was the sorriest excuse for a v8 gm ever put out...


Personally I wouldn't bother going from a 4.0L to a 4.3.....a lot of time and effort to swap it in for really no gain. The HP is pretty close between the Vortec 4.3 and stock TBI 350, but the 350 still had around 50 ft-lbs. more torque. But the key work there is stock and the power potential of the 350 is pretty much endless and relatively low cost. The 350 TBI engines didn't have super high power numbers if compared to current day engines, but at the time they were strong and much stronger than the previous generation carb'd 350 (TBI bumped up the HP around 40-50 as compared to the previous generation), and the TBI itself is not really the limiting factor but rather the heads, cam, compression ratio, etc... in rest of the engine.

I'm definitely not saying a TBI 350 is the be-all, end-all engine swap for a Jeep, but it is cheap and easy and can put out respectable power. Service diagnostic and repair is also pretty easy as compared to modern engines.

[Trigger]

Well, just looking around quickly on www.car-parts.com, I can pick up a 6.0L for the same price as a 5.3, so it looks like it might be a better route. I looked on AA, but can't find an adapter for the Gen III to TH400, but I'm sure they make one, then after that it's an Atlas. TomH, what did the swap end up running you, if you don't mind me asking. I'm thinking $6-$7K?

[TomH]

TomH, what did the swap end up running you, if you don't mind me asking. I'm thinking $6-$7K?

You're about right on. I picked up an '06 Escalade (LQ9) including the 4L65e and all of the accessories, ECM, harness etc. for $4K to my doorstep. The motor/trans was pricey, but it was virtually new (500 mi).

http://www.hachiya.us/jeep/blog/wp-content/uploads/2010/04/DSCF0062_thumb1.jpg

Between the cam, Atlas-II with adapters, VSS kit, headers, etc. there is another $3K (Max).

[jwend]

if it were me... I would go sbc 350 or 400 pane injected t400 and atlas, could do that for 3500.00 4000.00 with all good parts on it. but thats me.

[94Dodge Truggy]

I liked the jeep and how well it performed with mostly all jeep components except for the axles and suspension. Factory steering box, pump, motor, trans, t-case, body etc... Parts could be easily found at an auto parts store and a factory chiltons manual covered it. Not many rigs around that I have seen or heard of that could cover terrain as much as it could with mostly stock internals. Suspension setup was spot on and gearing was right.

[8UP]

Check Pirates classifieds for the Atlas. I looked around several months ago and there were several of them at the time. Could save you hundreds.

[gothodgie]

if it were me... I would go sbc 350 or 400 pane injected t400 and atlas, could do that for 3500.00 4000.00 with all good parts on it. but thats me.

I'd say SBC too... For what you mentioned your budget might be you could buy a new 350 crate motor and still have some change for go fast goodies, and you can find parts just about anywhere. Just my 2 cents.

http://www.summitracing.com/parts/MLL-BP3830CT1/

:beers:

[blazerbrad]

Well, just looking around quickly on www.car-parts.com, I can pick up a 6.0L for the same price as a 5.3, so it looks like it might be a better route. I looked on AA, but can't find an adapter for the Gen III to TH400, but I'm sure they make one, then after that it's an Atlas. TomH, what did the swap end up running you, if you don't mind me asking. I'm thinking $6-$7K?

If I had to choose I would definitely go with the 6.0L.

Isn't the reason there is no adaptor for a Gen III to a TH400 is that you don't need one? I was thinking the only thing to deal with is reprogramming the engine ECU so it is not looking for signals coming from the trans???

[f4isvt]

4.3 is always a good option like said close to numbers of a 350 with less weight. My buddy runs a highly modified 4.3 vortec in his mud bog truck and they make him compete in the v8 class and generally still wins or at least places. If they let him run nitrous he always wins.

[TomH]

The upside to the 5.7/6.0 Gen-III/IV GM motors over the 4.3 is bags of cheap reliable torque and HP without any exotic (i.e. Expensive) parts. The 5.3 is also a great option, but it comes down to what you can find for a donor.

The drive-by-wire versions run without hesitation in hot/cold, wet/dry, from the moment you turn the key and have lots of grunt from about 800 RPM up. A lot of guys go through the effort of changing them to cable throttles, but as easy as the ETC setup is to install, I wouldn't bother.

Good luck.

[JeffK5]

Go GenIII/IV 6.0 .. I bought a low miles LQ9 locally ..complete minus the harness for $900.. 345hp stock.

Add a cam and tune and your at 400 ponies for under $2k... thats hard to beat.

Jeff

[EricZJ]

i think you want low end power and fast response, out of a I6 stroker motor you will have that nasty low end torque where you need and i throttle response is excellent, my buddy has a cherokee with a 4.7 inline 6 he has plenty low end and it winds pretty high to

[GT MOTORSPORTS]

If I had to choose I would definitely go with the 6.0L.

Isn't the reason there is no adaptor for a Gen III to a TH400 is that you don't need one? I was thinking the only thing to deal with is reprogramming the engine ECU so it is not looking for signals coming from the trans???


You are right on the turbo 400 bolting up to the 6.0. The main issue is that the bolt that would be in the 3/4 o'clock position is untapped in the LS block(all of them) because the coolant passage is right there,so GM left it untapped. I can take a pic of my 6.0 in the shop if you need to see what im talking about. I will have to look also but I think I read somewhere you need to add spacers between the torque converter and flex plate. I could be wrong but it does come to mind.

Strickers auto parts in owensville has iron block 6.0 liter engines with 500 miles for $2500.00

Greg

[94Dodge Truggy]

what is coming of this swap? does the 4.0 still live? Can I buy the poor old 4.0?

[Trigger]

Everything is on hold for right now. I'm currently sitting in sunny Qatar. I will be back in November, and then I'm going to be paying for a wedding, so the V8 swap is a little down the road. Damn, I hate being responsible!

[flatlander757]

What gears/tire size do you have now?

I've got a bone stock 4.0HO in my 03 TJ... only thing done is 2.5" exhaust from after the stock header/cats on back. With 5.86s and 40" tires and being quite heavy for a TJ... it pretty much hauls ass. Everyone who has ridden with me(street or offroad) has pretty much **** themselves:evilgrin:

Edit:

And I did gears for a guy on JF(username MarineJRM) and he has a home-built 4.6L stroker in his XJ... that thing flat out hauls ass something fierce. He can burn the tires pretty much at will(35s). It dyno'd something impressive at the wheels too(around 200hp at the wheels IIRC?). He has a thread on JF documenting his stroker build, might be something to look at. ;)

[Trigger]

It's got 5.29s and 42" IROKs on it right now. It does very well and there's really not much it won't do, I just want a V8. :evilgrin: