Project In Progress '07 Base model - Project G2 Force!

[PierreNotPear]

Hey everyone, here's the start of my build thread for my 2007 Grand Prix base model!

Clear corners, SPO grills+wing, dual exit exhaust/valence, mystery wheels, ZZP front sway, the world's leakiest SD headers, shift kit and more small things I'm forgetting!
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There's a few things driving this project: A want for a faster car, without the budget or co-signers necessary to get my hands on the newest Hellcat, Zl1, or 5.0 like some of the other people my age are fortunate enough to be driving. Layered on top of that is a love for this old car and platform. For the first 130k or so of its life the car belonged to my father, thankfully he was a sensible driver who stayed on top of maintenence, so I'm lucky enough to be starting out with good bones here. Plans for the future at the moment are to turn this car into a homage to the G-Force concept car, a love letter to everything old dealer booklets made these cars out to be, and what they should be today. Sleek, stlylish, comfortable, and powerful, something that holds it's own against today's spread of high-horsepower offerings.

Right now I'm gunning to finish up the top swap I've been working towards for a couple of years now, switch over my headers, paint and add roof rails I've been keeping under my bed, refreshing suspension, and adding some autozone mufflers to really bring out it's V6 rasp and drone. I'd also like to wrap the roof black and add carbon fiber accents like the g-force concept. Interior-wise the plan is to just black out and suede everything I can, add some more carbon fiber accents to the trim, and POSSIBLY add a nice reclining recaro if i can make up a bracket for it to replace my sagging drivers seat.

 

Upcoming Project  2005 Grand Prix CompG

[ThatSlow.W204]

very nice, excited to see more progress on this build in the future

 

[PierreNotPear]

Cleaning up some heads and the SC for the swap, evaporust is a godsend for setting and forgetting crusty parts.

*** In case anyone happens across this thread and tries to use in as a how-to for cleaning things up for a top swap, DO NOT CLEAN THE CARBON OFF THE ROTOR PACKS/ROTOR PACK CHAMBER. IT JUST HELPS IT SEAL BETTER AND MAKE MORE BOOST. HEED MY WARNING!!!

 

[Last Indian]

A couple things. Have you ever upgraded the ECM? Consider doing what you can to increase the air intake. I.E. blueprint the throttle body & get more of a Ram air effect as opposed to a filter down in the front fender well.
Also do you have any plans for the transaxle? If so what?
Last, exhaust. I believe the exhaust on your 3.8 is basically the same as mine? If so most folks make a huge misstep in the aftermarket exhaust, IMO! You need a 3” down pipe to the cat, but if your system is the same as the 00 of mine, one welded piece, pipes resonator mufflers. Than the factory system from the 3” cat back will give you a throaty V8 sound & great power! The 3.8s are very sensitive to back pressure for power. If I could post a video I would let you here what mine sounds like, but I can’t! Can’t do a link, as I already asked Robert.

 

[PierreNotPear]

Since it's only NA for now the changes to the ECM are minor quality of life changes. Once I get the supercharger installed I'll start making more drastic changes.
As for throttle body and intake, I'd like to fabricate a fully-custom intake box in the future once I have a bit more free time in my life.
I've made very few changes to the transaxle, only a no-name autoparts store cooler and a transgo shiftkit to try and keep it together a bit longer.
I've made no changes to the exhaust other than ebay headers. I'd love to hear a soundclip of your car if you're willing to DM me a link?

 

[Last Indian]

As far as the throttle body; polish it like a mirror, including the throttle plate! Remember the throttle body only flows air! You typically want a rougher type surface when you flow fuel over a surface, but when it’s just air the smoother the better!
Good choice on installing a cooler! Best thing you could ever do for that tranny! How did you set it up? Did you run it to the radiator than to to cooler & back to the tranny or did you bypass the radiator? Likewise what fluid did you use?
Yes I can, I think, DM you. That would be to send an email with a link on this site. Right?

 

[ThatSlow.W204]

As far as the throttle body; polish it like a mirror, including the throttle plate! Remember the throttle body only flows air! You typically want a rougher type surface when you flow fuel over a surface, but when it’s just air the smoother the better!
Good choice on installing a cooler! Best thing you could ever do for that tranny! How did you set it up? Did you run it to the radiator than to to cooler & back to the tranny or did you bypass the radiator? Likewise what fluid did you use?
Yes I can, I think, DM you. That would be to send an email with a link on this site. Right?

Yea haha in most of our groups we heavily heavily put it into everybody’s head to install a cooler, these cars 1000000000% need it.

 

[PierreNotPear]

As far as the throttle body; polish it like a mirror, including the throttle plate! Remember the throttle body only flows air! You typically want a rougher type surface when you flow fuel over a surface, but when it’s just air the smoother the better!
Good choice on installing a cooler! Best thing you could ever do for that tranny! How did you set it up? Did you run it to the radiator than to to cooler & back to the tranny or did you bypass the radiator? Likewise what fluid did you use?
Yes I can, I think, DM you. That would be to send an email with a link on this site. Right?

I installed it a little over a year ago, but if I'm not mistaken I ran it as follows:
Tranny out -> Stock rad -> Aftermarket cooler -> Tranny in.
The unit is a shrimpy one from o'reilly, so I'd like to replace it with a Trucool 40k, bypass the stock rad entirely, and use fancy AN fittings for a cleaner install.

If I'm not mistaken you can send a DM by clicking on my profile, then clicking the "send direct message" button.

 

[Jasmindont]

Don't bypass the stock rad. Through hptuners I can confirm that my trans temp reaches stock temperatures while highway cruising (200+) Which I can't confirm this yet, would be a contributing factor to my coolant temp problems while highway driving. My stock rad and fans were seeing 200+ degrees of air before any cooling happened. Like I said, nothing confirmed yet but I would advise against bypassing the stock radiator trans cooler.

 

[Robert]

Wanna see something? https://www.youtube.com/@WBodyTech/search?query=trans cooler

 

[Last Indian]

Absolutely! Tranny out to rad. Rad out to cooler in. Cooler out back to tranny. Here’s my setup!
Also unfortunately the best ATF for these transaxles never made it to market thanks to GM. My company, as I said before was the company responsible for developing most of the products you use. Now most of the time the OEM’s give us the basics of what they want. This was the case here. In the late 1990’s they knew the had issues with these transaxles. We developed what became Dexron IV! Not VI, but IV. This was a very good lockup ATF, but GM likes a soft shift. So they finally approved Dexron IV. I have only used Dexron IV in the Indian since the beginning. Your best choice would be Dexron III (H) version. Sometimes it reads Dexron III-H. This is actually a stickier fluid than Dexron VI. There may be some aftermarket fluids that bite better than the III, but I haven’t tried any so I can’t speak to that.

 

[Last Indian]

Pierre, I run a ZZP front power log, stock crossover, stock rear steel exhaust. 3” down pipe with a cat. This down pipe eliminates the factory Ubend. From there back it’s a stock OEM one piece welded piece.

 

[ThatSlow.W204]

Pierre, I run a ZZP front power log, stock crossover, stock rear steel exhaust. 3” down pipe with a cat. This down pipe eliminates the factory Ubend. From there back it’s a stock OEM one piece welded piece.

Looks so pretty under there, did a very good job at making everything nice and keeping it rust free forever.

 

[PierreNotPear]

AAAAAAAAAAAAAAAND WE'RE BACK!​

School's out for thanksgiving, and what better time to top swap this total piece than now! I'll be updating the thread throughout the week as I progress through the swap, y'all feel free to chime in with any advice while I work through this. All the big-daddy fun stuff should be coming in over the next couple of days so it'll be a lot of trips to the mailbox.

Day 1's been slow, just cleaning up my lim and valve covers, with a nice shiny coat of paint on the latter. Once again, shoutout to evaporust for doing the cleaning I'm too lazy to do.

 

[Robert]

Looking forward to seeing it all done.

 

[Jasmindont]

Can’t wait to see her driving

 

[PierreNotPear]

Supercharger's been rebuilt, mating surfaces masked off, and paint has been huffed!
And remember kids, a kitchen sink is really just a free parts washer that comes with your house.

Now back to the garage for me, topend is halfway apart, and I'm gunning to get it down to the block in time for thanksgiving dinner.

 

[Robert]

Special Delivery! Base tune to get this going. Make sure you have both Map sensors plugged in. The NA has 1 and SC has 2.

 

[PierreNotPear]

Special Delivery! Base tune to get this going. Make sure you have both Map sensors plugged in. The NA has 1 and SC has 2.

... and so Christmas comes 24 days early, all thanks to Santa Rob!

Jokes aside, I seriously can't thank you enough for doing this for me, I'd be completely SOL without it.
Didn't know I needed both MAP sensors so I'll have to figure out how to wire the second in.

 

[Robert]

... and so Christmas comes 24 days early, all thanks to Santa Rob!

Jokes aside, I seriously can't thank you enough for doing this for me, I'd be completely SOL without it.
Didn't know I needed both MAP sensors so I'll have to figure out how to wire the second in.

Don't worry about it right now then, you maybe may not have a SES light, we will just need to know what codes you have if any at all.