Trey's *Twin Turbo 5VZ* Experiment Truck +Haltech Tips

Figured I should start something even though I'm 8 years in and trying to be done.

Current Build Highlights:
- 35x12.5 rear, 35x10.5 front Kenda Klever R/Ts on 17" 3rd gen wheels
- ADS front coilovers w/clickers
- Built Right Uniball UCAs
- Bilstein 5100s in rear + OME Dakar leafs
- Navy blue Raptor Lined body w/black accents
- Hood vent over turbo area
- LCA & SR Poly bushings
- Twin (modified) Ford Focus K03 turbochargers in parallel, one for each exhaust bank. Single bridged wastegate.
- Custom interior incl. mass-backed black carpet, fabric dashboard, overhead acoustic foam, vent gauge pod & A-pillar pods, insulation-stuffed dash & panels, matching blue seat belts, nylon door openers

In-Progress:
- Haltech Elite 2500 tuning Click Here to skip to setup & Tuning Tips!

Planned:
- Fixing some interior & exterior cosmetic issues
- Finalizing door panels & audio

Spoiler: Phase 1: Historic

I bought my first vehicle ever, my 1999 Tacoma Prerunner SR5 Doublecab at 68,000 miles from an old man out in Phoenix, AZ, when I was 19. I lost my data backups so here's roughly what it looked like (minus the weatherguards):




I come from a family with no car experience other than oil changes, and told myself that was going to change.

There were a few issues off the bat from a truck that had been sitting so long in the desert, so dirty I got replacing the TPS, resealing the charcoal canister, replacing the O2 sensors and catalytic converter, and probably some other things I'm forgetting.

Poor fuel economy led me to a journey of an itch I couldn't scratch, involving changing all fluids, seafoaming through the brake booster hose, and just a general tune-up over the first couple years.

Realized I could get some cheap but good suspension upgrades with Bilstein 5100s + OME so that's what I did, and I learned a lot from that 8 hour nightmare!



Throughout this experience I started to get neurotic about sounds, noises, and rattles, as I simultaneously gathered some minimum wage cash for my first sound system. This all quickly lead to a complete dissection of the interior: asphalt paper and open cell foam on the floor, full on 1-2" acoustic foam adhered to the ceiling, denim insulation in the dash and side panels - pretty much anywhere it would fit and not get wet, multiple attempts at sealing the door panels better and with much thicker MDF, doubling up on door and window seals, and putting cloth and insulation underlay on the dash and A pillars. The result was probably the quietest 1st gen interior out there. FYI, the biggest source of wind noise are the front windows - to fix this you really need thicker glass, or some way to bolster the seals (drip line inside the seals is not enough).

(pic was corrupted) Also pictured is the double lightbar & mirror combo I made (removed later).

Next I became obsessed with cars with a flat finish, and I knew my paint needed work, so I did the only thing I could afford: buy a harbor freight paint gun, compressor, and a few cans of Rustoleum, and go to town. Wow, it looked great!...for a while.





Then was my first turbo build using a $150 flux cored welder (still in college):





Wastegate clearance:


Intercooler mounting:


Fuel pump upgrade:


Front bumper raptor lined (has held up really well to this day):


Done?


The first startup spewed oil everywhere because I forgot to tighten the line lol, but it worked!
Only issue was I barely hit boost until I was on the highway, and the Split Second piggyback was not helping me in closed loop, which was a constant struggle to fix. All in all, a good first attempt and I ran this set-up for about 2 years before deciding to redo it.

Meanwhile, I convinced myself I needed racing seats with bolsters to keep me planted on turns, but I couldn't be bothered to pay an extra $100+ for custom brackets, so I made it work with some time and somewhat sketchy tube and bar steel. Couple that with being obsessed with sound for a while and you get this:

 

Phase 2 .... spoilers it's all Snapchat memories

Summary: Scrapped big turbo, went two small boy turbos from Focus STs. Tried for a low mount and an upper mount. Low mount was a nightmare.

Spoiler: View Images

 

Spoiler: Raptor Lining

Truck Raptor lined w/navy blue tint to preserve color cohesion with factory body


Black raptor on the little bits

Spoiler: Tundra Brakes

Tundra brake upgrade w/matching caliper paint and brake lines & shot of the ADS coils (installed backwards :/ ) & BR UCAs

This is how it currently sits, minus the truck rack which was sold:

 

Yesterday added the wastegate tube


But the angle ended up being too shallow so I had to patch it up and try again


All that's left is the left exhaust bank connection

 

After much fanageling, all 6 points now align. What a monster!




Tight fit.



MIG butt welding sucks and is ugly so once the ceramic paint is cured I'll probably add an exhaust wrap. It ended up cracking in some places where I ground it down.

 

Only thing better than a turbo is two turbos!

 

Simultaneously collecting 4x4 conversion parts and grabbed a transgo reprogramming kit




After a bottle of degreaser and painting the rusty spots

 

Made the primary downpipe tonight



Ignore the welds on the right - those are from long ago with my old flux core



Almost done with the rest of the plumbing as well, just need to drop the oil pan once more to weld another bung in then start up!

2nd air filter is gonna be tricky though, but can start up w/o it.

 

Looks ambitious, I'm really curious how much boost you will be running and how much overhead the K03's will have.

 

15psi. These little things go on the 2.0L ecoboost and push 20+ and they're undersized for that application from looking at the compressor maps (ride the surge line for faster spool). So 2x and running 3.4L instead of a 4.0 should make them perfect. I'm aiming for around 400HP and these are good for around 250-300 each looking at that platform

 

are you still on a stock cam?

I'm looking for a cheap setup to push past 7krpm around 10psi... I'm definitely finding I need to learn more about the different ecoboost setups if I want a cheap turbo!

 

Yes stock cams; cams would be the last thing I would look at.
No such thing as cheap to raise redline on a 5VZ - you need to convert the bucket style and upgrade the valvetrain. I'd probably do a custom intake manifold before I did all that to move the powerband up higher. Peak torque is only something in the 3600RPM range. Ofc cams would help with that as well, but the cost/performance ratio is off the wagon.

 

I swapped a 2gr into my truck, but I've been eyeing a twin K03 setup for a minute now.

 

Nice!
Lots of different K03s to chose from - I'd probably pick one off an Audi if I could. The necks on these Focus STs were a pain to deal with, and as you maybe could tell, I had to cut the intake ones. But they were $100 each (even less than an ebay turbo), so... worth it to me.

 

Dropped the oil pan (again) and installed another bung on the same side as the first one, and plugged the other side (3 now). Then adjusted the 10AN return fittings & lines.




And it runs!!
But it leaks coolant from the intake valley guess it's time for another teardown. Oh well, I had new injectors to install anyway.

The final challenge will be getting a filter to fit on the rightmost turbo, as I simply cannot wedge the one I have in that spot.



Oh, and brand new AGM battery, which rocks! (never had one before)

 

Ripped the intake off and installed new 650 (630)cc injectors, removed old piggyback (for sale in BST), and roughed in a Haltech 2500 yesterday (sorry, no pics until final).

Issues starting with the Haltech.... so tbd

 

Truck starts and starting to dial everything in from test drives...
Going to have some issues dialing in ignition timing though since these knock sensors are so unreadable. I still can't figure out even what frequency knock occurs at
Just all about more driving and locking those LTFTs in from here out I think. Then maybe I can fork out for a dyno tune on the timing...





Tbh though the idle vacuum to atmospheric regions seem mostly trivial. I hit effective WOT (0PSI in the manifold) at 10-15% throttle at 2500RPM on this thing.

 

Awesome build man. Looks like fun. I love my boosted taco

 

I am running Haltec too. Mine is a 2000. I got it all tucked in the jockey box.