3.9 to 4.6

GhostLs

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Does anyone have any experience with or know anyone who has swapped a 4.6L Mustang motor into the Ls? Other thatn the obvious need for the motor, tranny and ECM, what else would need to be done?
 
:lol: dude, the FORD ENGINEERS could not get it to work. If you want the 4.6, you're gonna have to buy a different car.
 
I will also add that it probably can be done, but you won't have a street legal car when you're done.
 
Don't laugh! I'm just exploring my options. There's a guy here in town swapping a Jag 4.2L Supercharged 6 speed into an LS He's pretty convinced he can do it. All he does is rebuilt LS' and T birds so he knows them inside and out. I just dont want to spend $15,000 on putting in the Jag motor and not see the hp potential I'm looking for.
 
Who is this guy that rebuilds LS's? You should send him to this forum. It would be interesting to talk to him.
 
If i recall several guys have done on here - there are a couple of threads you can probably search for - I believe they use a kit they got off e-bay.
 
I will get ahold of him and see if he is interested in joining the forum. He's a cop in the podunk town of Dexter Ks about 15 minutes from me and he rebuilds cars in his spare time. Lol I can't imagine anything to much going on in that town except maybe Bessie shooting at Earl when she comes home and find him in bed with his second cousin which is also Bessie's sister. Totally irrelivent to anything being talked about here but i thought it sound hilarious!
 
Hey Quik you mind elaborating a little? What kit and what forum? I did several searches before even asking this question to avoid "Beating a dead horse" but i didn't find what i was looking for.
 
Hey Quik you mind elaborating a little?
Quik is pulling your leg. AFAIK, the only Mod-motor LSes are the car a group of Lincoln engineers built for the One Lap of America (OLOA) and a test mule that never left Dearborn (some LLSOC members got to ride in that one; IIRC, its mill was a 5.0 Cammer). The OLOA LS used the PCM from a Mustang to control the powertrain, and pretty much everything else that makes the LS a streetable car didn't work.

It can be done, given enough cubic dollars, but you'll be blazing new trails if you do it.
 
How many cubic dollars do you figure? It would seem to me that it shouldn't be any different than any other type of swap.
 
Just as a quick note.. how much bigger is the 4.6 than the 3.9.. cause I don't know if you noticed but there is already a severe shortage of space under the hood of the LS.
 
How many cubic dollars do you figure? It would seem to me that it shouldn't be any different than any other type of swap.

If you have to ask this question, you have neither the money nor the ability to follow through on this.
 
I hate to hear that term spat out of anyone's mouth. It's so stupid. That's like saying close your eyes and take off running. How many great kings and rulers have had all the money and ability yet stood at the feet of their own crumbled empire. Knowledge is power and the pursuit of information is without a doubt more than necessary.
 
the 4.6 will fit - if loaded from the top. The 3.9 is the largest that can be loaded from the bottom - which is the way they do it at the factory.

So a 4.6 will fit. The Rousch SCed version had to have a hole in the hood cut because the SC added too much height.
 
there are many threads on engine swaps.

We do not have enough control over the LS's PCM to make a change this big - we cannot change cam or crank rotation counts, ..etc.

So you would have to bring the mustang's PCM with the engine. however, the PCM will not interface with the rest of the LS's 6 computers (FEM, REM, PATs, Dash Cluster, driver door, TC, ...ewtc) - so you'll basically have to gut the LS's wiring and put in the mustang's - including dash, PATs, .... The LS is the only Ford with the FPDM integrated into the REM.

This is not an easy or cheap job - but doable. now a company like SCT could probably modify the PCM at the low levels to do this - but it would be a custom R&D job and be very expensive.

you would also need to re-work the cooling system as the stock LS system is very near the edge of performance with the 3.9.

The extra weight of the 4.6+trannie would make you visit the car's balance, and since we cannot adjust camber,... you may have an issue there. THere are no aftermarket anti-sway bars - so if you have messed the balance up alot - your understeer may just be something to live with.

So it's doable - just not the wisest investment for the $$$
 
Thanks Quik that was an answer with some quality behind it. I would just really love to see my LS body cruising with around 500 hp under the hood! Finding the right path seems to be an issue. Obviously I could buy a mustang but have been there done that smashed it into a wall. I love the LS' looks and was looking to go to the highest level i could with it.
 
Why din't you look at the Jaguar, XJR engine? I haven't done the swap so I wouldn't be able to give detailed instructions, but I have pulled the power train out of my LS and see an XJR stripped. The engine should bult in. That dosen't include the electronics and the tune.
 
the electronics are the hardest part... as stated above. None of the Jag electronics are the same - so it's a swap, like anything else. If you're gonna do it - do it to something with an aftermarket.
 

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