1990 C1500 LQ9 Swap Questions, From Alaska.

Greetings fellow swappers... I was wondering if some of you would be kind enough to supply me with a little more information for a swap I'm hoping to complete in the near future. The truck is a 1990 C1500 that has a full air suspension, and will be body dropped after the swap. I'm hoping to swap my tired and worn 350tbi to a 6.0L LQ9 and wanted some details on the proper route to take. I'm not looking for huge power, I won't be doing any FI, and I'm interested in keeping the stock 700r4 (Monster Transmission Built).

Now my questions relate to the DBW/DBC throttle body... is it necessary to maintain DBC on the 2006+ engines, or can I convert to DBC by changing the TB?

I read on the forum that a majority of people that swapped over use mounts that move the engine 1" back to maintain close to stock positioning of the new LS motor, does this also go for the LQ9?

As for the harness I'll most likely purchase a custom piece from Nelson Performance... The price is just too good to be true, and I'd like to put the factory ECU in the front dash to hide it.

Any tips and tricks to aid/simplify the swap would be great, and a total parts suggestion list would be awesome!!!

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I know very little because I am in the process myself. I do know that one inch setback mounts work on the v8 frame mounts in your body style truck. That does work with all LS engines. I also know that you will need a ls1 Camaro oil pan to clear the bottom of your cross member in that you are lowered. The stock pan will hang below the crossmember by a fair amount, from what I understand it is about 2 inches. I bought a complete 2000 Silverado to use as a parts truck so I couldn't tell you about the drive by cable versus drive by wire. I believe the 6 liter uses a flat flexplate the does not require the spacer commonly used in the 5.3 to the earlier 700r4 or 4L60E swaps. Take all of this with a grain of salt and verify it for yourself because like I have said I am in the process of research myself.

I used the dirty dingo adjustable mounts and measured where my 350 was mounted and set the dingo mounts on the ls motor in the same location. Everything from there lined up the same as it was with the 350. If the intake manifold has a 3 bolt DBW throttle body you can bolt up the dbc TB . If the TB is a 4 bolt you will need an adapter. You also have to make sure if you go dbc that the pcm you use is compatible. The pcm has to have the drivers for the dbc setup.

^^ yup

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Originally Posted by gagliano7

I used the dirty dingo adjustable mounts and measured where my 350 was mounted and set the dingo mounts on the ls motor in the same location. Everything from there lined up the same as it was with the 350. If the intake manifold has a 3 bolt DBW throttle body you can bolt up the dbc TB . If the TB is a 4 bolt you will need an adapter. You also have to make sure if you go dbc that the pcm you use is compatible. The pcm has to have the drivers for the dbc setup.

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After doing some research I figured it would be easier to swap the pedal and related components into the truck, after searching around on ebay I figure the $100 or so dollars for the pedal, and the $100 or so for the LS1 TV kit would make the swap affordable and simple.

Skylark, Thanks for the info on the oil pan. The truck will be traditional body dropped after the swap so the more space the better.

Anyone have a part number for a radiator bracket for this year truck? I'm using E-Fans at the moment.

Do you already have the DBW pedal and TAC module? If so it's a nice swap and makes the cruise control easy to hook up and works really well. I'm glad I stayed with dbw and wouldn't change it for anything. But if you don't already have the parts then maybe dbc would be easier. Just be sure the computer you use is compatible with the throttle body you go with.

I was just going to purchase a DBW pedal and TAC off ebay, they're cheap enough that the point of going cable isn't really worth it.

I was also debating on getting a built 4l80e to go along with it.

Be sure they are compatible with each other. Not all dbw parts are the same. If you could get them all from the same vehicle and one that matches your ECM it would make life easier.
http://www.lt1swap.com/dbw.htm

Im not sure the dbw tb is going to jive with the 700r4. I dont think youll have anyway to actuate the tv linkage. I have an lq9 in a 90 454ss, as others said, 1" setback mounts are what you need. I sold off all the DBW stuff and picked up a cable harness/pcm/tb. I reworked the stock harness and the pcm in is in the dash in the stock location. You are going to want the f-body pan. I have the gmpp hot rod/h3 pan and its still about an inch below the crossmember.