I know its been done a million times. Just not by me. Picked up a clean rolling shell 86' MCSS and am in the process of bldg an lq9 (pistons on back order since i went with 3.900 stroke). Currently trying to get front area perfect for when engine is finally ready i can atleast drop it in. Going to run ls7 intake on the mast heads if that makes a difference. in south florida so ac stays. What im trying to figure out is what the hell can i get rid of from the engine bay? harness? bunch of stuff. i bought as a shell so idk what went where in the bay.
Swapping a 6.0 ls into a G body
- Thread starter johnnunez29
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I'm not doing the work myself, but I am in the process of having an LQ9 6.0 and 4L80 installed into my 1979 Olds Cutlass. I have a build thread titled Project Diesel No More. The shop doing my install used the Holley engine mounts and transmission crossmember. Everything fit with no issues. I understand there is an additional crossmember add on that was needed because my original trans was a TH250. If you use the Holley crossmember, you should check with Holley to verify what you need for your specs. You may not need that additional piece if your original transmission was a newer unit. One other minor issue since you are keeping A/C, the clearance at the heater box is tight. I wanted to use the taller "coil hider" valve covers, but due to the tight clearance, I used standard valve covers and relocated the coils, as I am also keeping A/C.
We love to see pics, you will have plenty of people chime in with valuable info I'm just not one of them
Following up, re the wiring harness question, I went with Holley Terminator Max X ECU and Dakota Digital dash (not fully digital, it looks similar to oem gauges, but with better tech). Dakota Digital makes an add on module that is a direct interface with the Holley ECU. So, none of the original engine harness was needed, and the level of effort for gauge wiring was drastically reduced. I also ordered a cruise control unit from Dakota Digital.
I'm interested to see how you are getting them LS7 Heads on a 6.0l
You have some things that aren’t adding up.
What are you goals? Asking because if you’re planning to run expensive heads, then either you plan to be racing or have a lot of money to burn. Not that there is anything wrong with burning a bunch of money, but for a street car you’ll be burning it.
Putting a stroker kit into the 6.0, getting the heads a fresh valve job, proper cam, springs and headers can yield 600 crank hp and still be driveable.
What are you goals? Asking because if you’re planning to run expensive heads, then either you plan to be racing or have a lot of money to burn. Not that there is anything wrong with burning a bunch of money, but for a street car you’ll be burning it.
Putting a stroker kit into the 6.0, getting the heads a fresh valve job, proper cam, springs and headers can yield 600 crank hp and still be driveable.
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I would have accepted 821 or 823 heads, but LS7? Why would you want to have big cube, high rpm tuned ports on a small cube, low rpm build. It's like admitting you hate low rpm torque in your street car, not to mention the self imposed limit you have for really good intakes.
I have a set of 823’s that I don’t intend to use if you’re interested.
Those heads work better on a 4.100" bore, will work on a 4" but better on a bigger bore.
Anything 4" or under the Cathedral Heads work great.
LS7 Heads require a minimum 4.100" if I remeber right, so yea still want to see how this person is building this setup.
MAST Heads are mentioned so it may be the small bore LS7 Heads they make, which will go on the 4" bore. They like RPM's tho so there's that.
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