New guy here. I've wanted a GTO for quite some time and finally got one about a year ago. I've lurked around a little but never signed up. The car is a 2006 auto. Was looking around and found it on marketplace one day-damn that market place anyway. I bought it as a roller February 15th of 2020. Spent about a month gathering parts and waiting for the snow to go away. Car was running and driving April 5th. Car is from Texas and has no rust anywhere on it. Has a few hail dings but very nice car overall. Was pretty much all there except for the engine, trans, accessories and the exhaust manifolds/midpipes. Rad and all hoses were there, ac lines, wiring harness, driveshaft etc.
Empty engine bay-it was this clean when I bought it. I didn't have to clean anything on it.
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Pics from the ad.
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Random trailer picture-was about 15 miles from home at this point when we stopped for fuel. Also the stupid V8 badges were removed off the quarters.
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I had initially planned on putting a 4.8 in the car that I had from a 2wd Chevy truck that I bought to put in my iroc Camaro. I found an LS2 not even a week after buying the car and decided I'd be better off with a 6.0 like what's supposed to be in the car.
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Cleaned the engine up pretty good and resealed it. New front and rear covers, front and rear mains, valley cover, pan gasket, OPSU, coolant temp sensor. Only thing I didn't do was headgaskets since I didn't see the need for that. Also did a baby LS9 cam for a little more power and keep the drivability nice. Did blue springs.
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Looked around on eBay was lucky enough to find a complete accessory setup. I had an LS1 intake I had bought from a buddy previously for the iroc project I never started. Used an ICT billet adapter to run the 4bolt DBW throttle body on the 3 bolt intake. Has an LS1 rail with injectors from a supercharged 2004/5 GTP. They're the correct length for the LS1 rail and plug for an LS2 harness. Pretty close in flow rate as well. I also ended up selling the LS1 intake for an LS6 over the summer.
Trans is a 4L60 from a buddy's T/A. The GTO has a single plug connector for the shifter position sensor-not sure when the actual name of that is. I ended up using one from a junkyard Envoy. The trans being for a T/A was meant for a 2 plug connector style. I had to swap the shift selector shaft which turned out to be pretty easy since I changed the filter anyway. The single plug sensors are thicker and need a longer shaft. The shaft was also super cheap at 10 bucks for a brand new one from ACDelco
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New/longer shaft on the left
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New shaft installed
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Motor/trans mockup. Has new GTO coil brackets with junkyard truck coils. I had MSD wires but they were too short so it has truck wires. Speed Engineering long tubes with 3" xpipe. Rest of the exhaust is stock.
I never could find an OEM trans dipstick so got a generic one. Brackets are kinda flimsy but it works. It didn't line up the best as it seems to be spaced too far away from the bell housing but I found out recently that a 4L60 with a removable bell housing is deeper than an older 4L60 so I think that's way. I'd like to find an OEM trans dipstick at some point.
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I also couldn't find OEM trans cooler lines so I got a Trucool 40K and made some -6AN lines. Cooler mounted. Uses one headlight bolt on each side and existing holes in the core support. No cutting or drilling.
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Before starting on the car I made some wheel lifts out of 2X4's to get the car off the ground. I'd say this helped a lot being able to roll around under the car with ease.
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Driver header laid in since we all know the rack has to be dropped to get headers in. Held in with a piece of wire. I still almost had to drop the rack to get around the shaft on the steering rack. Header ended up hitting the steering shaft. I replaced the mounts and that fixed it for awhile but seems to be hitting again. That header is going to get the hammer treatment come spring time when the car comes back out.
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Motor/trans in. Pulled the rad/condenser and put the motor and trans in together without much fuss. Pretty easy install really.
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Accessories on. Can also see where the trans cooler mounts to the headlight bolts
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Almost all buttoned up
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Another shot on the blocks
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More on the next post. I have to about to the pic limit.
Empty engine bay-it was this clean when I bought it. I didn't have to clean anything on it.
Pics from the ad.
Random trailer picture-was about 15 miles from home at this point when we stopped for fuel. Also the stupid V8 badges were removed off the quarters.
I had initially planned on putting a 4.8 in the car that I had from a 2wd Chevy truck that I bought to put in my iroc Camaro. I found an LS2 not even a week after buying the car and decided I'd be better off with a 6.0 like what's supposed to be in the car.
Cleaned the engine up pretty good and resealed it. New front and rear covers, front and rear mains, valley cover, pan gasket, OPSU, coolant temp sensor. Only thing I didn't do was headgaskets since I didn't see the need for that. Also did a baby LS9 cam for a little more power and keep the drivability nice. Did blue springs.
Looked around on eBay was lucky enough to find a complete accessory setup. I had an LS1 intake I had bought from a buddy previously for the iroc project I never started. Used an ICT billet adapter to run the 4bolt DBW throttle body on the 3 bolt intake. Has an LS1 rail with injectors from a supercharged 2004/5 GTP. They're the correct length for the LS1 rail and plug for an LS2 harness. Pretty close in flow rate as well. I also ended up selling the LS1 intake for an LS6 over the summer.
Trans is a 4L60 from a buddy's T/A. The GTO has a single plug connector for the shifter position sensor-not sure when the actual name of that is. I ended up using one from a junkyard Envoy. The trans being for a T/A was meant for a 2 plug connector style. I had to swap the shift selector shaft which turned out to be pretty easy since I changed the filter anyway. The single plug sensors are thicker and need a longer shaft. The shaft was also super cheap at 10 bucks for a brand new one from ACDelco
New/longer shaft on the left
New shaft installed
Motor/trans mockup. Has new GTO coil brackets with junkyard truck coils. I had MSD wires but they were too short so it has truck wires. Speed Engineering long tubes with 3" xpipe. Rest of the exhaust is stock.
I never could find an OEM trans dipstick so got a generic one. Brackets are kinda flimsy but it works. It didn't line up the best as it seems to be spaced too far away from the bell housing but I found out recently that a 4L60 with a removable bell housing is deeper than an older 4L60 so I think that's way. I'd like to find an OEM trans dipstick at some point.
I also couldn't find OEM trans cooler lines so I got a Trucool 40K and made some -6AN lines. Cooler mounted. Uses one headlight bolt on each side and existing holes in the core support. No cutting or drilling.
Before starting on the car I made some wheel lifts out of 2X4's to get the car off the ground. I'd say this helped a lot being able to roll around under the car with ease.
Driver header laid in since we all know the rack has to be dropped to get headers in. Held in with a piece of wire. I still almost had to drop the rack to get around the shaft on the steering rack. Header ended up hitting the steering shaft. I replaced the mounts and that fixed it for awhile but seems to be hitting again. That header is going to get the hammer treatment come spring time when the car comes back out.
Motor/trans in. Pulled the rad/condenser and put the motor and trans in together without much fuss. Pretty easy install really.
Accessories on. Can also see where the trans cooler mounts to the headlight bolts
Almost all buttoned up
Another shot on the blocks
More on the next post. I have to about to the pic limit.
