3800Pro Forums banner

"Bad Grandpa" 2004 Turbo 3800 Regal GSX Upgrades

5918 Views 39 Replies 6 Participants Last post by  dezldave961
I've been posting this on the TurboBuick forum (Grand National guys), but it's more appropriate here.

This spring, I decided to overhaul my 11-sec grandpa car Buick that I originally built in 2009 with a Z7 T66 2.5" turbo kit, and go with a full Stattama T67 3" setup. The shutdown helped & hurt this project, as it's given me time to do extra things at a slower pace, but delays when parts may be available.

Car Profile link (same as in my signature): https://sites.google.com/view/efistreetperformance/home/gm-3800-cars/dave-04-regal-gsx
Best 2009 1/4mi: 11.46 @ 122, 1.87 60ft - YouTube Video (with 1998 Regal commercial theme music... didn't realize Top Gear, too, never watched it)

2009 collage of build pics from profile page:

Mock-up of Stattama kit while I waited for Holden intake to arrive from Australia this summer:

Holden intake mock-up (more info will be in videos):

2020 Upgrades - Part 1... (1st attempt at a video edit in 10yrs)

2020 Upgrades - Part 2... (tried to keep it short, and still working bugs out of my editing)

I'll post more updates for this build here when I get a chance. The engine is almost ready, once a few more small pieces arrive to bring it together.

- Dave
See less See more
  • Like
Reactions: 1
21 - 40 of 40 Posts
Update after a couple weeks just cruising and enjoying it:
  • Got a new HPTuners to supplement/replace DHP use, and will be adjusting the file soon (old tune is still very close for basic driving around)
  • Lowered the front another inch on coilovers
  • Got Nitto 555 G2's all around (255-50-17), look great and grip awesome, just gotta be careful cuz they're intentionally soft and will wear quick
  • Aligned today at local shop, and it should be ready to play


(after adjusting down from ~4.26" gap)


Set of 4 Nittos from Summit


Getting aligned with lasers!!! (guys at the shop loved the car, and that there's an aftermarket for 3800's)
See less See more
Install video of the ZZP coilovers. Hope it came out clear enough to let people decide if they want to go that route:

Just cruising with the new setup, enjoying the ride around here with folks.
Started the morning headed to a Cars & Coffee, wound up at a local car show & won the 2000's class (2000-2009). That was random! Gotta show up to win, I guess.

(Do all that work to make it go fast, and it gets its 1st trophy sitting still.)


See less See more
Quick walk-through of that car show. I'll have 1/4mi race prep and in-car footage put together soon.

Got out to the track last month. Ran in street trim, and on slicks, to get the dust off. Been 11yrs but got back into 11's, for now. Video with details should be put together eventually, but been busy at work.


See less See more
Made a prep video just talking thru as I got it ready for that Test N Tune last month. Some random tips/notes sprinkled in as I narrated my thoughts along the way.

Race video will be edited together from GoPro in-car footage this week. (more entertaining than this stuff, but I'm sharing the steps along the way)

Fresh 2004 GTP engine in after spinning a bearing at 7k rpm in the 2006 block during the May track trip (picked up the engine the next week, but got busy this summer). Videos uploaded last month or so.

Added (either due to oil issues, or to improve runs):
  • ZZP oil pressure kit
  • ZZP 3500 stall (was 3000)
  • CX T72 BB .68 A/R T4
  • ZZP lifters (LS7 style)
T72 T4, T67 T4, T66 T3/4
Wheel Tire Automotive tire Tread Synthetic rubber

Automotive tire Tire Wheel Tread Synthetic rubber

Automotive tire Wheel Motor vehicle Bumper Engineering

Tire Car Wheel Vehicle Automotive tire

Vehicle Car Wheel Tire Automotive lighting

Video will be made soon, but I realize I didn't post the last couple, so feel free to see them on the channel link.

Hoping to hit the same track in 2wks, then maybe a couple more outings before the end of the year.
See less See more
Got the car running, and just putting some local miles on it (commute and store trips), so I can work the bugs out.

Wanted to hit the track here in VA tonight, but rain delayed that idea, so I'll get more ready with higher boost tuning for the next chance.

I guess the new setup was too much for the flex to handle...
Automotive tire Wood Grey Motor vehicle Plant

I knew it was a little loud, and I feared that a weld on the new 3" Stattama pipe/wastegate already cracked (see my Z7 kit that had this common issue among stainless turbo stuff that gets hot). Changing the engine angle with the shorter dogbones for lower coilover use, and cradle spacers for hood clearance may have played a big part, too.

That also explains why my Wideband O2 6" below this flex is reading lean everywhere but full throttle. Oh well, guess I'll have to set aside some bucks for a replacement downpipe, or this is an excuse to track down a local fabrication shop that does TIG for a new flex on this and the repairs for the Z7.
See less See more
Guess I haven't updated for a while. Was busy overhauling the GXP and F-150 before moving cross-country and getting into a new-to-me house.

Latest update is that I've driven the Regal a bit, but it had a high idle/squeak, and needed some DIY alignment adjustments after I messed with the coilovers a bunch.

After doing a homebrew smoke test, it looks like I need to reseal the intake or injectors, so I decided to swap back to the L26/HV3 setup. (Really just wanted an excuse to prep the Holden intake for cool appearance mods.)

Motor vehicle Hood Vehicle Car Automotive design

Also doing some tweaks on the vac lines and intake pipes for clean-up to make it easier to work on and look a little nicer.

Also, since I'm back in the Midwest corn country, I may finally do the E85 conversion (only 91 here, too). Currently have a Walbro 255, 60# Mototrons, and a 4.0bar Bosch regulator that loved going up to 26psi on race gas. We'll see how much that setup can deal with on E, but I'm guessing I'll be upgrading beyond that system soon.
See less See more
Yer nearer to meh?


Also your regal is slow.
Ya, a few hours SW of you guys. I'll hit up some meets/events your way eventually. 1320's Ice Cream Cruise is here in 2 weeks, though.

It's pretty weaksauce. Haven't turned it all the way back up in forever, either. Maybe the corn will let me crank the dial and leave it, rather than tap-dancing between 93 and race gas settings.
Even when it's only e70 it's well worth it.
every morning its like your setting fire to a distillery
It's probably going to be stupid hot here (95-100+), still, so I'll skip standing around an asphalt track to stare at cars this weekend, unfortunately.

In the meantime, I've just finished swapping back to the L26 UIM setup. Had to space my N* TB adapter 3/4" further out to fit past Stattama wastegate, and still had to remove cruise for now.

Runs alright, but chasing a small vac leak and A/C isn't happy, yet. I can tell the good torque (Holden) vs. top end (L26/HV3) difference immediately with the butt dyno. This is meant to be used at the track, though, so I'll save the other intake for when I decide to leave it back in street-only use someday later.

Vehicle Motor vehicle Car Automotive design Auto part

Car Vehicle Automotive parking light Grille Automotive lighting

Car Vehicle Grille Hood Automotive lighting
See less See more
  • Like
Reactions: 1
Dude I just finished digitizing that flange and I water jetted one out of 1 in aluminum for a custom. I kind of almost want to build the Lehman Style dual plenum intake schtuff on a bell mouthed fbody lim.
Perfectly straight short trumpets right at the valve throat.
I always figured that if I went with injector in head, I could shove a 3.8L plenum on there.
Maybe I should just fog the underside of the TR with fogging oil and drive it this winter with studded snow tires, maybe take it to the ice drags on 20psi rofl
damn dave your making my engine swap look like a dirty mess🤣🤣🤣. Super clean bro love the photos. Can't get over how clean and nice all your set up is. Looks like you could eat off that motor and transmission.like the content especially the videos on YouTube keep it up.
Thanks, it's been a good distraction to overhaul it the past couple years. We built it nice in 2009, and I finally got the chance to just keep making it more like I want for a finished product.

Still bugs to work out before I get to start putting many miles on it for the coming years, but it's close and works for occasional work commutes at the moment.
  • Like
Reactions: 1
Dude, this is awesome. That is all I have to say right now. 🤯
Appreciate it. Got a couple small tweaks for this spring, and it should be back to routine driving as I get ready to race and such, again. I'll share more footage once I'm upgrading intercooler pump, converting to bigger fuel pump/injectors for E85 since I'm in corn land, and cleaning up some interior wiring for gauges and sensors.
  • Like
Reactions: 1
21 - 40 of 40 Posts