Hi,

I just registered with this forum after spending MANY hours over the past week reading threads... This definitely seems to be the place to learn about the topic I'm interested in: an LSx swap into a Jeep TJ

My dad and I own TJs. His is a 2004 and mine is a 2005. Both are unlimiteds (the extended length models), and mine is a Rubicon.

About a year ago we went down the path (regrettably) of attempting to get more horsepower out of our 4Ls by adding turbos from a company I'll refrain from naming since we are in a lawsuit trying to get our money back. The turbos definitely added power. BUT... because of the piggyback computer approach used and not enough development of the product they introduced all sorts of problems and extremely bad gas mileage. After months of problems and never getting them resolved we had the turbos removed and have been trying to get our money back ever since... Enough with that cuz the whole topic makes me sick...

We have begun to seriously look into the idea of throwing late model LSx engines in our Jeeps for all of the obvious reasons. We don't race or hot rod. As a matter of fact my Jeep is my daily driver while my dad's Jeep is a toy for him. We do take the Jeeps to Colorado and do some climbing... But we just would like a comfortable and enjoyable amount of horsepower through all normal driving situations.

So far we find ourselves looking at the following engine/tranny combo:I'm finding these engine/tranny combos on eBay as low mileage (under 20K miles) "liftouts" with computer, wiring, brackets, starter, alternator, power steering pump, drive by wire pedal, etc for $3,500 - $5,000.

We're trying to keep the price tag from getting too outrageous, but we also want to end up with Jeeps that have really nice performance.

So here are my initial questions:Thanks in advance for any input. I really appreciate the things I've already picked up from you guys reading through this forum...

Below are a couple pics of my Jeep as it sits today...

Also a couple of pics of the latest project my dad and I just finished (had some more cable cleanup to do, but this was first time out of the shop). We bought the frame, engine and common components. And we added the rear "fender" to the frame and fabricated the front "fender", handlebars, seat pan, various bracketry...

Also a couple pics of dad's softail we built last year. Ya, that's 2 pics of the same bike. It's color-shifting paint...

Rob


Edit Note: I guess the title of this thread is misleading. Maybe it should be "TJ LSx Conversion"... After discovering that there is an LSX series of engines I'm correcting myself to say that I simply meant one of the LS engines...

.

 

Try car-parts.com for engines and trans.

I have a 98 wrangler with a LS6/$l60e combo. Drive it every day. Just got back with it from the Power Tour. 1500 miles and ran it great. 18 MPG at 65 to 75 mph. I used Novak to adapt the trans to the 241R. Howell for the computer and wiring harness.

It's a great swap.

 

pm MeanYellowZ for an engine / tranny setup. He can do ALOT better than that and set you up. I've used him and he's a good vendor.

YatesEFI.com

 

Thank you guys for the quick responses. I will definitely follow up on the leads...

A question about fit/alignment: Also, I know this is a subjective question... but... What is the performance like with a 5.3 Gen III or Gen IV engine? Dad and I are trying to decide if the 5.3 is sufficient or if we should look at a larger engine...

Thanks for the input...

 

I'd bet a stock 5.3 would do you fine but you can make alot of power with that motor with some mild work. I took a 100K mile one, added a magnacharger and 228º cam and I have myself a legit tire fryer. It's stupid off idle.

 

Out of curiosity what kind of boost are you running?

Since you mentioned a cam... My dad (and I) love the old school lope of a carbureted engine with a decent cam idled pretty low...

Dad has been trying to find out if a fuel injected LSx with a decent cam can be idled down and have the kind of lope you used to be able to get. Do you know?

Thanks,
Rob

 

I would go 6.0 if it was me. Lots of low mileage stuff for $1800 or less for the engine. Put a small cam in it and have 400 hp at the crank. I had one in a 99 Wrangler.

My LS6 is about 425 hp. Rebuilt to stock LS6 specs, LS6 cam, 1.85 comp cam rockers and BBK intake. If I was to do it again I skip the LS6 cam and comp rockers and go with more cam. Not much but a little.

I have 4:10 gears in mine with 32 inch tires. It's very quick off the line. The 4:1 in the 241R makes for a nice low range option.

See pics of my engine before I had the sheet metal back on. I a nut shell you move the engine back until the back of the cylinder head is about 3/4" from the fire wall and over to passenger side so the exhaust header clears the upper right control arm. The Novak adapter has the trans mount built into it.

 

LS1 TJ,

Just so we're on the same page... what would you call "low mileage"?

I did a quick search on car-parts.com and didn't come up with a lot of LS6 options currently. Just a ballpark question: How long would you expect to have to shop around to find a good overall deal on an LS6?

We're trying to decide how far in advance of the project starting do we need to be seriously searching for engine and tranny...

Also... in regards to a cam... my dad has had some input that a 228r is a good cam to go with... any thoughts?

Thanks for the help,
Rob

 

No advice on the cam but I consider low mileage 30,000 or less. I'm builiding a 67 Nova with 2009 L92. I paid $3000 for the engine with the front accessories. 1400 miles.

Unless you are set on a alumimun block I would go iron block 6.0. Much cheaper than a LS6 and with a cam the same performance. As I understand the 6.0 heads are the same as the LS6 with bigger chambers for lower compression.

 

I have been thinking about swapping my SBC to a ls style engine in my jeep also. From what I have found most the time the 6.0 or the 5.3 are a lot cheaper than the ls1/ls6. Unless you can find a really good deal on a ls engine I would go with the iron blocks they tend to be a lot cheaper. I have been trying to decide if I would wanna go 6.0 or 5.3, I really want the 6.0 but it seems like they are going for about double the price i can find 5.3 for. I reciently found a complete 5.3 with 40k for $800.

As far as the cams go there are tons of options out there, really depends what you want and what you wanna do with the jeep. There are deff some of the bigger cams that will make a ls engine lope. Search on youtube for some videos with sound clips.

 

Any more suggestions on how to find good deals on LS engines?

I've been watching eBay and searching car-part.com and my local Craigslist locations...

 

Just do a 5.3 with a used Z06 cam or 224/224 114LSA cam, ported TB, and headers with a tune and you should be fine. 5.3's are waaaay cheaper than 6.0's. Also they get a few mpg better. For a Jeep it'll have plenty of torque.

I bought a used 2004 5.3 with 34K miles complete with everything including accessories/harness/PCM for $750. It is being put into a Ski Centurion water ski boat now.

 

I put a 2000 LS1 from a vette in my '90 YJ. You can read my build thread here: http://www.jeepforum.com/forum/f12/9...-notes-554809/
I just recently replaced the manual with a 4l65e and am in the final cleanup of that swap. So far, it has been a great swap, working out some computer issues with the move to the electronic trans. But, hope to have that worked out this week.

I am going to be putting some kind of LSx in my '65 GTO this summer, just not sure exactly what at this point. So far, really like the motors and since I am a computer guy (could not fix a carb if you paid me), the programming/tuning has been okay.

 

Hi Fred007,

I just read through your swap... man, that Jeep has gone through a transformation! Great job!

As my dad and I continue to try to decide on what engine for the performance we're looking for every data point helps...

Can you tell me your engine's hp and torque from the factory? And what is it like to drive the Jeep now compared to before the swap?

We are looking pretty seriously at 5.3s with around 315 - 325 hp and 325 - 345 torque (depending on year/model/etc)...

We'll be running 4L60E trannies and plan to use our (NP231 on dad's and NP241OR on mine) Jeep transfer cases... So I'm really interested to hear what yours is like with the auto...

Thanks for the great swap info!

Rob

 

My 98 Wrangler started out as a 2.5 with a five speed. Not fast but ok around town. 2.5's came with 4:10 gears stock. The 2.5 is my base line.

First swap for 98 was 4.8 LS and a AX15 five speed. Drove it for two summers and it ran really well but the shifting got tiresome. Bought a 99 Wrangler with a 2.5 and auto trans and put in a 2003 6.0 and 4L60E with the 231 transfer case. 3:73 gears. Still had the 98 Wrangler. The 6.0 was great to drive. Very snappy off the line. Stock the 6.0 is rated at 315 hp.

I decided to restore the 98 and bought a 2000 LS1 and 4L60E. Rebuilt it to
LS6 spec by adding the 243 heads and cam. BBK intake and Comp 1:85 rockers. The LS6 is very quick off the line. Because of the coil suspension it lifts the whole Jeep when you hit gas hard. A bit unnerving until you get used to it.The 4:10 gears help. The LS6 is 405 horse stock. With the rebuild, intake and rockers I'm thinking 425 hp.

Sold the 99 Wrangler with the 6.0. Drive the 98 daily and plow snow with it in the winter. I've had it up over 100 mph and it's still pulling. I would compare it to a 6.0 liter chev truck with 1000-1200 less pounds to drag around. I would bet most four wheel trails 4 high would be enough. It's a great swap.

 

LS1 TJ,

Just tonite my dad and I were discussing this again, and we think we're gonna head toward a 6.0L swap. We think that we would probably be happy with a 5.3L, but with a little patience and shopping we think we can get a 6.0L for not too much more (probably an LQ9 which has factory HP of 345 and torque of 380)...

Thanks for the description of the differences in your Jeeps. I'm really hoping that the LQ9 will make for a fun ride...