1961ba427

iTrader: (26)

First off let me say I know this is probably posted in the wrong section because it is LSX into an already LSX powered vehicle. If someone will direct me where to post I will gladly move it.

I have the chance to get a nice 2005 Silverado LQ4/4L80E that is currently running, but the owner is pulling the engine and trans to swap into a 1957 Bel Air along with the truck's ECM. The truck's wiring, driveshaft, etc. would stay with the truck.

I want to get the truck and put it back on the road as my own truck is tired and I haven't found anything decent nearby in my price range. (Looking for something in the $5-6k range and avoid payments.)

I would be buying a new 4L80E and ECM as I work at a Chevy dealership so that part is fairly affordable.

For the engine I have a 2013 L96 long block as well as some other parts that I could mix / match to come up with something decent. I'm not looking to build a hot rod truck (right now) just a good truck.

What I'd have:
1. 2005 Silverado 2500 2wd LQ4/4L80E complete less engine/transmission.
2. A good running low mile 2013 L96 long block - no intake, water pump, or accessories.
3. 2006 GTO LS2 short block only - I know this has a 24x reluctor, but it needs a few rods and possibly more work.
4. Unknown model iron 5.3L complete from intake to pan with accessories and bad cam/lifters.
5. Pair of 243 heads ready to bolt on.

I haven't been on this site in years so I'm not current on everything and need all the help I can.

What I think my cheapest and still good route is:

1. Swap the LS2 crank with 24x reluctor into the L96 engine to make it compatible with the 2005 ECM and harness. Will this cause a serious balance issue or would this be still within factory tolerances? I'm thinking okay since it's a 6.0L crank.
2. Swap the camshaft, timing set, and front cover for the LS2 parts so that I have a cam signal at the front that is compatible with the 2005 as I think there is no place to install a GEN III sensor in the rear top of the L96 block.
3. Swap the heads from the L96 (hate to do that) to the 243 heads so I can use the cathedral port intake from the 5.3L and a 3 bolt DBW TB that is compatible with the 2005 ECM.
4. Move the knock sensors to the side of the block by retapping the holes.
5. Use all the external stuff from the 5.3L to complete.

I think all this should run okay with the new ECM just programmed back to stock for the LQ4 as it would be very similar except for the GTO cam being slightly bigger and the better 243 heads.

Am I missing anything that would help or is going to be a road block??

I checked and the 2006 GTO used the same small knock sensors on the side of the block that the L96 uses, yet it was a 24x engine. Could I just use those and avoid tapping the holes and using the larger Gen II sensors?

I also know about the Lingenfelter box to adapt the L96's 58x to a 24x signal, but I don't like the idea of it going out and a replacement not being easy to get or years from now - impossible to get.

I know this is a long post, but I know a shorter one would just leave everyone asking me a lot of questions before you can advise.

Thanks for any and all help in advance. Jason

-TheBandit-

iTrader: (1)

I'll take a stab, but take my advice for what it's worth - I have very limited experience.

Regarding your plan #1, I think swapping to the LS2 24x reluctor crank will not be a problem. You will need also need to swap to the 24x sensor (one is gray, one is black, I don't remember which is which) on the side of the block.

Regarding plan #2, yes the L96 is a VVT engine so you will probably need to swap in a non VVT cam, timing gear, and front cover from the LS2. What I don't remember is if the L96 is AFM/DOD. If it is, that is yet another thing you'll need to eliminate and I think you can do so by swapping the LS2 lifters and valley cover over

Regarding plan #3, yes you could go to the cathedral heads and that would make everything more easily compatible. If you wanted to keep the L96 heads, you'd have to dig up an intake and adapt the throttle body

Regarding plan #4, I think your gen III wiring harness and computer will be setup for the knock sensors in the valley pan, not the side of the block, and I don't know what rewiring and/or reprogramming would be required to make this work. I think this might be your biggest roadblock to using the gen IV engine with the gen III computer/harness. There are probably others than can chime in on this or somewhere you can search for info. Maybe you can use a gen III valley pan and knock sensors from the 5.3 assuming it is a gen III 5.3L, but you might have to plug the oil feed holes for AFM using screw in plugs or something and I honestly don't know if using a gen III valley pan is possible on a gen IV block.

1961ba427

iTrader: (26)

Thanks for the help. I do know the L96 I have is VVT, but is not AFM/DOD. I'm not looking to keep the VVT, but will probably hold onto the parts in case that is something I want to look into using in the future.
You wouldn't believe how much time I've spent on here and other sites searching for more information. There is a lot of stuff out there, but a lot of it is misinformation as well.

Hopefully some more people will reply to this. Thanks for getting it started off!!
Maybe I should make some threads asking individual questions instead.

-TheBandit-

iTrader: (1)

Happy to chime in. I hope it helps. I think the biggest question I would have is on the knock sensors because the LQ4 gen III has them in the valley and the L96 gen IV has them on the side.

1961ba427

iTrader: (26)

I've seen several people post to just retap the holes in the sides of the block for the larger thread size of the gen II knock sensors and move them there. Then others say that won't work unless the ECM is tuned for them because the sensitivity is different. ?? I'd think if the ECM had to be tuned anyway then it'd be easier to just use the smaller gen IV ones that already mount to the sides of the block. ??

The 2006 GTO LS2 used the 24x system and yet had the newer knock sensors on the sides. Same part number sensors as the L96. I wonder if it's as simple as extending the wires to there and running them.

My other big hurdle seems to be the throttle body IF I wanted to stick with the L96 (L92 style) heads. I think the easiest thing there is to use a 4 bolt to 3 bolt adapter on a rectangle port intake.....but that would limit power for sure. I made another thread asking about that.

1961ba427

iTrader: (26)

I think that instead of swapping to the #243 heads and using the truck cathedral port intake I have that I should just keep the L96 heads and buy a rectangle port truck intake to match plus a 4 bolt intake to 3 bolt TB adapter to run the 2005 DBW TB.

I should have thought about an adapter sooner. Still hoping there are other things I haven't thought of that would ease the process and save money.

-TheBandit-

iTrader: (1)

If you go with the rectangular port heads and intake, be aware of injector size/compatibility as well as MAP sensor. Wiring may be different and ECU may need programming to accept.

WBB73169

i was wondering how things are going with the swap ? I recently picked up a l96,crate engine it is brand new. I want to put it in my 2002 Chevrolet 1500 HD it has an lq4 engine.It came with a intake TB, and 48# injectors. Now that I have read your post I now know that this is not going to be a plug an play thing ! So it sounds like I may have got my self in a spot . I'm old school, throw a engine in it and hook up a couple of wires and throttle cable ! Lol ! So I guess the first thing I need to know is where to get this 24x to 58x wire thing ? Thanks .

G Atsma

Lingenfelter makes the 24x-58x box

WBB73169

Ok, I have no idea what that is ? Box , ecm ? I can rebuild a carb but when it comes to electronics an fuel injection I'm lost .

G Atsma

It's a conversion box where you plug in the engine crank and cam sensor plugs into, and the other side of the box plugs into the engine computer. Makes the computer thing there's a Gen III engine hooked up to it. If you don't understand any of this you might want to start reading up on what these engines are about.

WBB73169

Yes , I have been reading about these engines and I'm learning a lot. that's a $300 dollar fix . So after I do that then I'm left with the knock sensors and hooking up the throttle body. I have been reading about the X link , not sure how it is to replace the cable yet. At this point I'm still a little lost but getting better. I have also been reading about a e-fan swap , while I had the front end pulled off I might as well do that too.

brandon6.0

iTrader: (32)

Best route would be to get a 2005 truck harness and ECU (This will be completely plug and play)

1. Use a ls3 truck intake manifold (so u can use the ls3 heads)
2. Reuse the original truck tb with an ebay 4 bolt adapter.
3. Relocate stock gen3 injectors down beside block. (Retap for sensors)
4. Use the Lingenfelter crank conversion box.
5. Do away with DOD. Nothing but trouble down the road.

Ive done a lot of these swaps and know them in and out.

WBB73169

I have a L96 long block complete with intake and throttle body crate engine. So when you say wiring harness , do you mean the computer to I assume ?

brandon6.0

iTrader: (32)

Yes as well. U will need a ECM.

brandon6.0

iTrader: (32)

I just did a 04 Avalanche 6.2/6l80e swap. Used the original 2013 6.2 harness. I converter it to standalone. Had a big time with the gauge setup. After 08 everything is canbus for the gauges etc. So u have to get Canbus interface gauges for everything to work correctly. Customer wanted the original 04 avalanche gauges to work with the swap. Had to send them off to be converted over to canbus. Big Pain but ended up working nicely once finished!

that's why I suggest reusing the original harness with the Lingenfelter box. Makes life way easier!