First time poster, I’ve been lurking on this site for years. I guess I should say I’m new to LS engines because I’ve never owned or swapped one into anything. I’ve always messed with SBCs and some other odd ball engines. I’ve completed and daily drove Mesgasquirt conversions so I am familiar with that type of EFI. My last install was a crank fired SBC using LS coils.

I have a 94 Jaguar Vanden Plas, XJ6, or XJ40 whatever you want to call it. I bought it with the intentions to do this conversion. It’s a very solid car, has some cosmetic wear, and has 164k miles. It runs good but with that many miles I don’t trust it for long hauls.

I am going to buy a complete truck. I have 2 choices,
2001 4x4 1/2 ton Silverado with a 5.3
Or
1999 GMC 4x4 3/4 ton with a 6.0
Both are headed to the scrap yard so I am able to purchase either for a good price.

I am almost overwhelmed with the amount of LS swap Info. As far as physically getting it into the car will be no problem. Cooling and fuel system will be no problem either. What I am stuck on is how to go about “tuning” it. I’ve been reading through some threads on here but most seem to discuss more of the mechanical side of the conversion.

A few things I want are, Cable throttle and a 4L80E trans. I would like to ability to boost it down the road with a single turbo, but with a 6.0 that may not be necessary.

I’ll get to my questions finally.
-After reading through posts and watching YouTube videos it looks like I will have some cash in hardware ($800ish) to be able to make changes to the ECM myself. Does that sound right?
-Say I go with Megasquirt to handle the engine, can I retain the stock trans controller or PCM to handle the transmission?
-If I use all of the factory stuff from the 3/4 ton, will I have any problems with the tune if I use a 2wd trans instead of the 4wd one?


I do apologize if I am asking questions that have been answered a million times. Either way I would like to start this thread so I can post pictures and hopefully get some help when needed.

 

So I have decided on the 01 5.3 LM7. I am also tossing the idea of going with a 4L60e, if I stick with a stock PCM then I may never turbo it because I most likely won’t want to mess with tuning. If I would, I think I would go megasquirt from the start.

I have been reading about using the stock harness and fuse block. I feel ok going with a stock harness, but I am doubtful of the stock fuse block. LT1swap.com has been very helpful, and they have a write up on a DIY Fuseblock but I feel like there should be more to it than 2 relays and 4 fuses. Am I wrong?

After looking at the stock fuse block diagram I feel that there should be 4 relays including the A/C relay.
Looking at the original fuses I counted 9 that I believe I would need to keep.

#11 15a even injectors and coils
#15 10a VCM/PCM Keyed 12v
#20 15a odd injectors and coils
#23 10a MAF, CMP
#30 20a Fuel Pump Relay, VCM/PCM constant 12v
#31 15a heated O2
#32 15a heated O2
#40 10a A/C
#49 10a Auto Trans shift lock solenoid

I am unsure of #49s need, but am I way off by thinking I need these fuses? I would just rather build my own fuse block rather than buy something.

 

Have you checked Jags that run? they're probably the go to for Jag swaps.

 

They seem to be behind, they don’t have any information on LS swaps. There are a few other companies that specialize in V8 jaguar swaps, but none offer LS stuff for my year of car.

 

Why go to the trouble of running a Megasquirt when the LS engine's original fuel injection is quite dependable?

If picking those two engines, I'd pick the one with the lowest mileage or best compression and oil pressure.

I can most heartily and completely recommend the use of tuning software that is frequently discussed here on LS1Tech called "Tuner Pro RT" and "LS Droid" - search for "LS Droid" here on the site. These two programs can very nicely support everything you need to do with this swap and they are free of cost. Save your money and don't do a mail order tune or pay somebody local with HP Tuners. Plenty of us here can get you through this aspect of your swap . . . no sweat. Buy an extra or two inexpensive (~$38) junkyard PCM's so that you can experiment with different tunes. I'm up to four different 0411 and 896 variant PCM's from your era of swaps and I have yet to turn one into a brick, wheel chock or pirogue boat anchor.

Build your own fuse block. Those junk yard fuse blocks out of the donor vehicles are massively too large, IMHO. On the other hand, I bought my engine harness from "PSI" and my body harness from "American Auto Wire" so I may not be the best source of advice here.

The 4L80E transmission is considerably larger than a 4L60E. Will it fit under a Jaguar?

What about engine mounts to keep your driveline angles towards the differential aligned correctly?

Rick

 

The only reason I consider Megasquirt is because it’s what I know I guess. I used it in my daily driver for years and feel comfortable with it. I do know I will NEVER get it dialed in like the factory, especially at cruise and idle.

I’ve been searching for days on how to make changes and tune the stock PCM and it seems like HP Tuners and EFI live are all that’s mentioned. So if I go with Tuner Pro RT or LS Droid, what hardware do I need to do it myself? I’d love to be able to do that so I could make modifications myself without needing a tuner or bothering someone to mess with it for me. I will spend some time researching both of those.

After reading through multiple write ups, I feel I’ll have no problem modifying the stock harness and making my own fuse block. All of my megasquirt installs were from scratch and I built the fuse/relay panels for them. None of that should be a problem.

I think this would be perfect for a fuse block and would look clean.
11 way fuse block
I used an American Auto Wire universal harness in my Karmann Ghia and I was impressed. For the price it couldn’t of been beat.

The V12 Jags actually had 4l80e transmissions stock, so I am sure it will fit. This car will
never see a drag strip, it is and will stay my everyday driver. I think I will go with the 4l60e.

For motor mounts, I am not sure? I have access to a lot of equipment, fabricating them won’t be a problem. I have not seen anyone drop an LS into this year jag so I am on my own.

Thank you for the Reply Rick!

 

Hello,

For tune writing with these two programs, build yourself a bench wiring harness using junk yard PCM connectors, wiring and the under dash OBD2 data link connector. There are plenty of You Tube videos on how to construct the harness for whatever red / blue connector P01 PCM or blue/green P59 PCM that you wind up with . After that, it is essential that you power your harness and PCM with a 12 volt power supply that is something larger than a 12 volt wall wart power supply. Reading a PCM is a low amperage operation but writing might need as much as 1.5 to 2 amps and the little wall wart supplies just can't hack it in this department. I use an old Radio Shack three amp bench supply. You can absolutely brick a PCM if your supply voltage drops too low during an operating system write operation. LS Droid has a recovery routine that's fairly dependable and this particular circumstance of failure is not the fault of LS Droid. But why tempt fate here writing with a cheesy power supply?

You will also need a Bluetooth "OBDLinkMX+" OBD2 device - maybe $80. LS Droid works for me using Bluetooth via an Android Samsung S9+ phone and writing a 512k byte P01 PCM takes around 11 minutes. A 1 megabyte P59 box takes double that.

Rick

 

I didn’t look too hard at the LS Droid stuff because I have an apple phone and computers for the most part. I have a nice older windows machine with a solid state hard drive and XP that I use for EFI and sound processors. It should work great for this.

I came across Moates stuff, it was looking like $175 for their “Ostrich” and a ALDL cable to use with Tuner Pro RT. I’m open to either one though. I can’t believe I haven’t seen this mentioned in all of the threads I’ve waded through, it’s so much more
affordable. I’ll check out YouTube like you suggested to learn more.

There was another 5.3 truck that’s headed to the scrap yard. If it’s got the same PCM I’ll just pull it out and cut the harness from it. I’ll learn to ropes on it like you suggested. I’m in no hurry for this, so I’ll have time to get everything ready.

 

Researching the LS Droid, what phone do I need? I have all IPhones so I’ll have to buy a Droid. What is the cheapest one I can go with? And I will need this correct?

https://www.obdlink.com/mxp/

I snagged a PCM with the connectors. I will have to go back to get a obd2 connector. So I’ll have something to play with.

 

Get a used Android phone that supports Android 7 or newer. I think a Kindle running Android will also soon be a suitable choice but not quite yet. I don't believe these need cell tower data service but they do need a Wi-Fi connection so that the use of older, obsolete versions of LS Droid can be prevented.

Rick

 

Well Android 7.0 phones are dirt cheap on eBay, TCL trac phones are $20. I am kind of leary about off brand phones though. I would prob spend the extra cash to get an LG or Motorola.


$60 on amazon for the Bluetooth link.

So I could be into that for $80, plus a new power supply for bench testing. I just can’t wrap my head around why folks are still using HPtuners or EFIlive?

When I eliminate a wire from the harness, will it need to be removed all the way back at the connector? If I do go with LS Android, I will be able to make changes to the VE table and timing Tables?

Thanks for the help!

 

I think HP Tuners and EFI Live (zero experience here with it) are probably easier to use and at least for HP Tuners, they support almost the very latest engines - and not just General Motors. Don't forget - LS Droid here is mostly for doing the writing to the PCM though some editing is possible -- segment swaps. To make other major changes to a tune, I'm using a program called Tuner Pro RT and then take that BIN file and put it onto an Android phone for the actual writing.

When I eliminate a harness wire, I de-pin it from the PCM connector. It's completely gone, not simply clipped and taped for insulation.

I have not done VE or timing changes in Tuner Pro but the tables are there. I'm pretty sure you can make those changes but I've only done much easier things within my tune.

Rick

 

Rick,

i just read through the thread created by the member who created it and that cleared up a lot of my questions. He actually mentions in one of his most recent posts that a Kindle Fire will work, so I guess I am going to steal my 4 year old daughters Kindle to tune my PCM lol.

I am going to go snag a few more PCMs to have as spares. I pulled the PCM connectors out of a vehicle and cut off as much as I could for my bench harness. When bench testing should I remove all the pins except the ones going to the OBD2 port, 12v supply and ground?

 

I remove all extra pins from the large, blue PCM connector leaving only the several 12 volt power, two grounds and the serial data line.

Please note - blue connector pin 19 and pin 75 are battery positive inputs. Full time battery, not an ignition key switched source for the battery. Blue connector pin 20 and pin 57 are ignition key switched sources of power. These differences and connections are important.

Sometimes, you will be directed to turn ignition key 12 volt power off but leave 12 volt battery power applied and you should construct your bench harness with separate switches between the power supply and PCM for this. Hopefully, you will never find yourself in a potentially bricked PCM recovery mode but having your power lines set up this way will assist you in preventing a hard brick situation.

For me, I always turn battery power on first, then ignition power. When shutting down my bench harness, its ignition power off first, battery power off last.

There's plenty of You Tube videos on how to build a bench LS wiring harness.

Edit: I don't believe the Kindle version of LS Droid has been released yet. He has talked about it but I think its still an Alpha release available only to a few or maybe nobody but Pete.

Rick

 

Just throwing it out there even though it sounds like you know a bit of info about ls droid, The driveway engineer youtube has a video or two about ls droid and writes some stuff and installs it. Not sure if it will help you or not but there is info out there for you or others who may be interested in going this route.

 

I will most definitely check it out! Thanks! I hate to keep asking questions on here if I can figure it out myself. Being a megasquirt user, I am all for DIY. HP tuners and EFI live just seem too expensive.

 

I got my donor vehicles,

99 2500 4x4 iron headed 6.0 with a 4L80E PCM Serv. #09354896
01 1500 4x4 5.3 with a 4L60E PCM Serv. #12200411

The 6.0 is for the Jaguar, the 5.3 is for my dads 944. I would like to keep the 5.3 complete with the harness, but will probably rob the PCM for the 6.0 in the jaguar. I have a few questions about the best way to go with the transmission. The car isnt light being over 4000lbs, it will never see a drag strip, and I seriously doubt I will ever run a wide tire on the back being this car is a daily driver. I am torn between a 4L60E and 4L80E. The 4L80E would be nice because I could easily use a stock bin file for the engine and transmission, while using the stock harness for the 99 6.0. But, I can use the 4L60E I have in the 1500 if I have the tail shaft changed. Id much rather go with the 4L80E, I guess ill get to my question,

Will I need to use a certain year 4L80E to work with my 99 6.0 harness and a 0411 PCM?

I purchased an OBDX Pro VT USB only and got it working with PCM Hammer. After alot of reading and questions I got the right XDF file and was able to open it up in Tuner Pro.

 

Picture of the car. Best $500 I’ve ever spend.

 

Nice looking Jag! And nice running, I can bet!