Thinking L67 swap on our dying GXP.
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00Beast
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Thinking L67 swap on our dying GXP.
Thoughts? Andrew said I'd be best getting a donor and getting everything from that. Who's game for an engine swap meet? Talk me into/out of this people! I figure if I can get this all done for similar to the $3250 that the dealer wanted for the HG's, I'd be ahead, even if it wasn't perfect. Be a great way to keep the G8 off the streets this winter...
Bye Bye:

RIP sandrock

RIP sandrock
Sirius wrote:Think about it. You’re tooling down the road in your Prius, knowing full-well that this thing being green is as big a sham as federally mandated ethanol-enriched gas, Russia pulling out of Ukraine, and Obamacare.
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94SilverSSEi
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Re: Thinking L67 swap on our dying GXP.
I'm sure you should be able to find a good donor for much less than $3,250. Be awesome to find one smashed in the rear with low miles.
That Northstar should still be worth a good bit, in aluminum scrap
That Northstar should still be worth a good bit, in aluminum scrap
Clay
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1968 Bonneville 400ci w/TH-400-40k
1999 GMC Suburban SLT-191k
2005 Escalade 253k-GINA
1997.2 40th SLE-138k
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- repinS
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Re: Thinking L67 swap on our dying GXP.
Stud the Northstar?
You have a lift!
You have a lift!

Jerry /// Past: 95 SSEi (June 2010 COTM) -- 04 GXP (July 2011 COTM)
91 Honda Civic Wagon DX 2WD (fuelly) -- 208,000km -- 92hp -- Autocross Warrior
09 Lexus LS460 AWD -- 94,000km -- Daily Driver
09 White Hot G8 GT -- 155,000km (fuelly) -- LS3 Cam -- GM LS3 CNC Ported Heads -- Kooks 1 3/4" Long Tube Headers -- Solo Catback Midsection -- Hooker Maxflow Mufflers -- Pat G Tune -- Rotofab Intake -- Tein S-Tech Springs -- GXP FE3 Dampers -- BMR Subframe Cradle Inserts -- BMR Subframe Connectors -- Forgestar F14 Gold 18x9 +40 -- Michelin Pilot Super Sport 245/45/18 -- Maverick Man Carbon Fiber Spoiler
- crash93ssei
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Re: Thinking L67 swap on our dying GXP.
repinS wrote:Stud the Northstar?
You have a lift!
This. Stud it and never worry again and keep the V8 rumble!
Ryan

2003 Bonneville SSEi - The Black Mirror SOLD!
2002 Bonneville SE - The Mutt Complete 2004 SLE interior, drivetrain, and body harness swap, ECC swap, HUD swap, black GXP wheels, GXP headlights and tinted tails - SOLD
2003 BMW 540i M Sport, 2001 BMW X5 4.4i, 2010 GMC Acadia, 2017 Grand Design Imagine 3150BH
1982 Cutlass Supreme - The fun one

2003 Bonneville SSEi - The Black Mirror SOLD!
2002 Bonneville SE - The Mutt Complete 2004 SLE interior, drivetrain, and body harness swap, ECC swap, HUD swap, black GXP wheels, GXP headlights and tinted tails - SOLD
2003 BMW 540i M Sport, 2001 BMW X5 4.4i, 2010 GMC Acadia, 2017 Grand Design Imagine 3150BH
1982 Cutlass Supreme - The fun one
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00Beast
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Re: Thinking L67 swap on our dying GXP.
That thought has occurred too. I'm exploring options. I just like the idea of building the "ultimate GXP" OEM style versus haro's which is modded to hell. The next thing would be to stop me from modding it...
Bye Bye:

RIP sandrock

RIP sandrock
Sirius wrote:Think about it. You’re tooling down the road in your Prius, knowing full-well that this thing being green is as big a sham as federally mandated ethanol-enriched gas, Russia pulling out of Ukraine, and Obamacare.
- crash93ssei
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Re: Thinking L67 swap on our dying GXP.
Stock for stock the N* just wins hands down for me. Sure the L67 can be modded for more power and has more down low, but the N* is the track star and let's face it... sounds like sex while the L67 sounds like a giraffe puking. The wiring seemed simple enough from what I remember, but he also had to change out all of the fuel lines which I think would be a major pain.
Studding the N* would cost less then 1/3 of the cost the dealership wants and also likely cheaper then a complete parts car, you would have a hard time finding one before Andrew got it anyway
Studding the N* would cost less then 1/3 of the cost the dealership wants and also likely cheaper then a complete parts car, you would have a hard time finding one before Andrew got it anyway
Ryan

2003 Bonneville SSEi - The Black Mirror SOLD!
2002 Bonneville SE - The Mutt Complete 2004 SLE interior, drivetrain, and body harness swap, ECC swap, HUD swap, black GXP wheels, GXP headlights and tinted tails - SOLD
2003 BMW 540i M Sport, 2001 BMW X5 4.4i, 2010 GMC Acadia, 2017 Grand Design Imagine 3150BH
1982 Cutlass Supreme - The fun one

2003 Bonneville SSEi - The Black Mirror SOLD!
2002 Bonneville SE - The Mutt Complete 2004 SLE interior, drivetrain, and body harness swap, ECC swap, HUD swap, black GXP wheels, GXP headlights and tinted tails - SOLD
2003 BMW 540i M Sport, 2001 BMW X5 4.4i, 2010 GMC Acadia, 2017 Grand Design Imagine 3150BH
1982 Cutlass Supreme - The fun one
MattStrike wrote:It was the worst week of my life! *pause, drinks beer... smiles* But I'm better now!
- nos4blood70
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Re: Thinking L67 swap on our dying GXP.
Stud the northstar. Then you can't mod it, and it'll be forced to stay on DD status.
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macksdaddy77
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Re: Thinking L67 swap on our dying GXP.
buy a donor swap the l67 and u could possibly put the northstar in the ssei lol? weird thought but u could have the northstar completely redone and then play with the internals. if im not mistaken u can still port and polish and put a cam in correct? u could maybe make u r own intake. and there is a tune now so i mean it could be intresting
- nos4blood70
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Re: Thinking L67 swap on our dying GXP.
The intake and porting and polishing would likely do next to nothing for the N*. And cams would have to be custom...
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macksdaddy77
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Re: Thinking L67 swap on our dying GXP.
dang.. lol
- RJolly87
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Re: Thinking L67 swap on our dying GXP.
How many miles on the GXP anyway? It looks like a coin toss here, especially since you have a lift.
~Randall~


1993 Buick Park Avenue - 197k - Some odds and ends done - Simply won't die
1994 Buick Regal - 78k - Bone stock - Always ready for a good kicking
1990 Oldsmobile 88 - Gone to a better place


1993 Buick Park Avenue - 197k - Some odds and ends done - Simply won't die
1994 Buick Regal - 78k - Bone stock - Always ready for a good kicking
1990 Oldsmobile 88 - Gone to a better place
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Re: Thinking L67 swap on our dying GXP.
This worked very well for me. The G8 is causing me to hemorrhage money.nos4blood70 wrote:Stud the northstar. Then you can't mod it, and it'll be forced to stay on DD status.

Jerry /// Past: 95 SSEi (June 2010 COTM) -- 04 GXP (July 2011 COTM)
91 Honda Civic Wagon DX 2WD (fuelly) -- 208,000km -- 92hp -- Autocross Warrior
09 Lexus LS460 AWD -- 94,000km -- Daily Driver
09 White Hot G8 GT -- 155,000km (fuelly) -- LS3 Cam -- GM LS3 CNC Ported Heads -- Kooks 1 3/4" Long Tube Headers -- Solo Catback Midsection -- Hooker Maxflow Mufflers -- Pat G Tune -- Rotofab Intake -- Tein S-Tech Springs -- GXP FE3 Dampers -- BMR Subframe Cradle Inserts -- BMR Subframe Connectors -- Forgestar F14 Gold 18x9 +40 -- Michelin Pilot Super Sport 245/45/18 -- Maverick Man Carbon Fiber Spoiler
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94SilverSSEi
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Re: Thinking L67 swap on our dying GXP.
repinS wrote:This worked very well for me. The G8 is causing me to hemorrhage money.nos4blood70 wrote:Stud the northstar. Then you can't mod it, and it'll be forced to stay on DD status.
Is that a bad thing, Jerry? More Racecar?
Clay
1997.2 40th SLE-138k
1968 Bonneville 400ci w/TH-400-40k
1999 GMC Suburban SLT-191k
2005 Escalade 253k-GINA
1997.2 40th SLE-138k
1968 Bonneville 400ci w/TH-400-40k
1999 GMC Suburban SLT-191k
2005 Escalade 253k-GINA
nos4blood70 wrote:Literally, cars are drugs.
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Re: Thinking L67 swap on our dying GXP.
My point exactly, Ed. You already have the G8 to mod. How has RWD V8 not cured you of the FWD V6 insanity?! XPrepinS wrote:This worked very well for me. The G8 is causing me to hemorrhage money.nos4blood70 wrote:Stud the northstar. Then you can't mod it, and it'll be forced to stay on DD status.
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Re: Thinking L67 swap on our dying GXP.
Insanity is insanity. Ask Will.
Idk what to do. All I know is that I don't have any time to do any of it.
126k on the car...
Idk what to do. All I know is that I don't have any time to do any of it.
126k on the car...
Bye Bye:

RIP sandrock

RIP sandrock
Sirius wrote:Think about it. You’re tooling down the road in your Prius, knowing full-well that this thing being green is as big a sham as federally mandated ethanol-enriched gas, Russia pulling out of Ukraine, and Obamacare.
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macksdaddy77
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Re: Thinking L67 swap on our dying GXP.
would u build up the l67 a bit or just a straight swap?
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Re: Thinking L67 swap on our dying GXP.
Same way I am Carl. I know all too well.
Will
91 Riviera | S2 L67 Swap/4T60E | 127K mi | Antelope Met. w/ Tan Int. | Saved From Death By Crusher
92 Bonneville SSE | L67/4T60E | 77K mi | Med Slate Grey w/ Two-Tone Grey Int. | Low Miles Time Capsule
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91 Riviera | S2 L67 Swap/4T60E | 127K mi | Antelope Met. w/ Tan Int. | Saved From Death By Crusher
92 Bonneville SSE | L67/4T60E | 77K mi | Med Slate Grey w/ Two-Tone Grey Int. | Low Miles Time Capsule
92 Lumina Z34 | LQ1/4T60E | 177k mi | Torch Red w/Grey Int. | Rusty In Odd Spots
99 Tahoe LT | L31/4L65E | 276k mi | Spiral Grey Metallic w/Grey Int. | Truck for Truck Things and Portable Concert Hall
02 Bonneville SSEi | 171k mi | Black w/Neutral Int. | Backup and road trip car
03 Park Avenue Ultra | 212K mi | White Diamond Met. w/ Shale Int. | Southern Time Capsule
05 Acura RL | 165K mi | Carbon Grey Pearl w/Ebony Int. | The Super-Hooptie Daily
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Evilcowboy420
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Re: Thinking L67 swap on our dying GXP.
This is my opinion and I know I am new but I figured I would throw my opinion in if you don't mind 
scrap the northstar I seem to have bad luck with them. I am sure there are the exceptions out there but unless your talking about it being a LC3 Northstar I wouldn't keep it. The early 4.6 were a little crappier in my opinion than the others. Technologically speaking the engine was dying in comparison to other V8's. But as is such GM still using an outdated engine.
Now studding is the cheapest option hands down and can be done with relative ease from what I have seen. But to me I personally feel there is something wrong when a person has to do such an intense mod in the 100 to 140K mark of the engines life. To me that should be uncommon.
As for trading the L67 in there. It is going to be a lot of work and very expensive to be happy with it since your use to the sound and feel of the V8. But it is a good sounding engine when modded right. There is a fella on youtube I watched do and in depth series of modding one and he did a very nice job. But you can tell it was a costly job. the idle was real nasty on the car and was extremely quick.
I personally am partial to the 3800 even thought it could still stand to shed a few pounds and this might account for my hatred of the northstar but head gaskets don't fail as often on the 3800 as they do on a northstar and if the engine was ever overheated in it's life it runs a big risk of warping not only the heads but the block as well being aluminum and all.
But all that said if it were me and I was looking for more power and a better engine I would combine the best of both worlds and try to source the LC3 and stud it. A supercharged V8 is always good. Too bad GM didn't use em more than 3 years.
anyway I hope that helps somewhat good luck on the swap.
scrap the northstar I seem to have bad luck with them. I am sure there are the exceptions out there but unless your talking about it being a LC3 Northstar I wouldn't keep it. The early 4.6 were a little crappier in my opinion than the others. Technologically speaking the engine was dying in comparison to other V8's. But as is such GM still using an outdated engine.
Now studding is the cheapest option hands down and can be done with relative ease from what I have seen. But to me I personally feel there is something wrong when a person has to do such an intense mod in the 100 to 140K mark of the engines life. To me that should be uncommon.
As for trading the L67 in there. It is going to be a lot of work and very expensive to be happy with it since your use to the sound and feel of the V8. But it is a good sounding engine when modded right. There is a fella on youtube I watched do and in depth series of modding one and he did a very nice job. But you can tell it was a costly job. the idle was real nasty on the car and was extremely quick.
I personally am partial to the 3800 even thought it could still stand to shed a few pounds and this might account for my hatred of the northstar but head gaskets don't fail as often on the 3800 as they do on a northstar and if the engine was ever overheated in it's life it runs a big risk of warping not only the heads but the block as well being aluminum and all.
But all that said if it were me and I was looking for more power and a better engine I would combine the best of both worlds and try to source the LC3 and stud it. A supercharged V8 is always good. Too bad GM didn't use em more than 3 years.
anyway I hope that helps somewhat good luck on the swap.
- Ghosthawk
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Re: Thinking L67 swap on our dying GXP.
I've done tons of number crunching on engine swaps and all of mine just involves parts and no labor. To me, the overwhelming factor is always how much has to be changed in order to make an idea work. Brainstorming is always a very cool thing and we consider it to be possible usually because we've seen the results of another persons work, which is all good, but when the work becomes your own the monumental size of the task starts to look like Mt Everest.
Anytime you can mod/improve/repair, and most importantly to be made reliable (the essential element for a DD) then sticking with whatever existing base you have usually comes out best. I love the rumble of a V8 as much as any gearhead on the planet, but any option I've looked at to swap my L36 for a V8 turns into the cost of another used car. In the end, I will most likely stick with my L36 and maybe add a SSM90 blower kit or possibly a turbo, but neither of those will cost a kings ransom to pull off.
To sum up, I agree with many previous posters. Stud the Northstar because that has been proven to make the engine reliable. You will remove the bite of the mod bug (at least from the Bonneville) and leave that for your other animal. The Bonne will be the better winter ride due to its FWD, and the repair will take far less time that an extensive engine swap.
Anytime you can mod/improve/repair, and most importantly to be made reliable (the essential element for a DD) then sticking with whatever existing base you have usually comes out best. I love the rumble of a V8 as much as any gearhead on the planet, but any option I've looked at to swap my L36 for a V8 turns into the cost of another used car. In the end, I will most likely stick with my L36 and maybe add a SSM90 blower kit or possibly a turbo, but neither of those will cost a kings ransom to pull off.
To sum up, I agree with many previous posters. Stud the Northstar because that has been proven to make the engine reliable. You will remove the bite of the mod bug (at least from the Bonneville) and leave that for your other animal. The Bonne will be the better winter ride due to its FWD, and the repair will take far less time that an extensive engine swap.
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- techweenie
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Re: Thinking L67 swap on our dying GXP.
I've read rumors that porting the heads on a northstar can yield as much as 50hp. If you're gonna take them off, at least take a crack at it. It certainly won't reduce any power. Since this is such as high revving engine, it makes sense in my head that even the slightest improvement to air flow could have a large impact. That is all theory I will be starting to put to the test later this year.
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2002 S10 ZR2 - my favorite truck in the world
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1994 S10 Blazer - 5" lift, narrowed ZR2 rear end, 32x11.5 tires, parting out due to overwhelming rust


