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5,384 Posts
Discussion Starter · #1 ·
I finally got around to snapping some half decent pictures of my twin turbo setup. I was hoping to be the first twin turbo GE is300 but for financial reasons I had to put the project on hold for a year and was beatin out :(. But I think I get to claim only Air to Water IC :-D

(2) T3 Super 60s (Originally wanted t3/04 42 trim? but they were way to big..$200 wasted)
(1) Tial 46mm wastegate (spring between .2 and .35 bar depending on how the car feels)
Custom made nickel plated manifold, I originally wanted stainless but was advised against it for cracking reasons.
Custom DP (V BAND) 2.5 inch form each turbo with a stock exhaust flange
600ish CFM Spaerco A/W IC with 2.5 inch inlet/Out
Large drag racing Heat Exchanger
3 Gallon Fuel cell for water tank
10 AN Russel Proflex hose for all water and turbo drains.
4 AN proflex hose for oil feed Teed for each turbo with equal length hose to each turbo and pressure restrictors for each turbo.

2.5 inch mandrel bent (and shittly welded by me)
Greddy Type S BOV
Turbohoses silicon( $$$$$:( )

(2) 2.5 inch tubes (from each turbo) into an XERD into the stock rear section into a HKS Dragger II, No cats.

RC 440 CC primary injectors
Walboro High flow pump

GS400 Iridium gapped to .028(A BIZZATCH TO GAP)

Greddy emanage W/ Map sensor (Ignition not wired yet)
Toyomoto 02 Sim
AVC R Boost controller

Defi Boost VSD
Defi VSD Concept (Oil Pressure, EGT)

Wide Band
Tech Edge

Now for the pics (I know my car needs body work :p)

One turbo is mounted high right under the pipe feeding the Intake manifold the other one is low behind the thermostat and alternator. You can see both tubros feed a Y pipe which merges and goes behind the head light into the IC which is mounted behind the fog light.

The air is then cooled by water and then fed straight back up in the Intake Mani. Nice and short. Youll notice the tubro feeds equal length so both turbos get even flow.


Just another pic giving you a better view of the first turbo, notice the EGT placement.

My gauge setup.
I really like the Defi VSD Concept HUD display. Very easy to look at even in the bright sunlight, the boost VSD I dont know about. In the glove box I have the Defi Link and HUD controler. I also have my Wideband mounted in there. I got the unit from Techedge for maybe 420, and the thing works awesome the wires you see on the right are TPS, RPM, and the map signal, so i can log everytthing thing I need to tune my car and it has a tremendous sample rate. I can use my PC to log or a palm.

3 Gallon fuel cell used as a water tank. The water goes from the tank into the IC to the Heat Exchanger and back to the Tank. (Lots of very expensive 10 an hose)

Pic of the heat exchanger.

Obvious Questions

Why twin?
dunno... to be different? when I first started I took my engines dyno got some compressor maps and said hey I want full boost under 3000 rpms, based on that the t3 super 60s seemed a fit and Ive always wanted a Twin Turbo Car.

Do you hit full bost under 3000 rpm?
NO:p , not yet we shall see.

Why Air to Water?
To be different, there is huge debate over A/W vs A/A, some quick benifits of A/W is less pressure drop through the IC so I dont need as much boost from the turbo so there is less heat generated. Better throttle response from the shorter piping, and the big one is to be able to load the water tank with ICE and have colder the envornment intake charge air. which ill do for autoX.

Why not a tuners kit?
hmmm, almost went tbko it fell through and at that time the Tuner kits where so pricey I decided to do it myself. I spent far more then a kit though.

Was it worth it?
This is MHO, but the some of kits the tuners where selling a year to a year and a half ago were running time bombs. I know a shit load more now, and I dont honestly think some of the kits where safe. Im also not a patient person when moneys involved. Do I recommend this? If you into cars yeah, I DID alot of reading, mainly on other boards and some books. Read the tec III manual which I thought was a Great read. But in the end a turbo is a turbo.

1500 Mile review. (6 psi)
The car runs well, boosts very nicely below 80 (1st - 3rd gear) it doesnt seem as fast on the highway. I suspect my exhaust restriction is hurting my ability to boost on under the load of highway speed. The car is street tuned only by my maps are pretty good, nice partial throttle acceleration. I do have a annoying backfire, but I think I need to totally redo my emanage maps to get rid it mine are scaled like shit.
I am pleased with the fact that out of boost it drives like stock, actually feels a little faster out of boost then before.

So far 21 MPG highway 15 City.

The CAR IS QUIET, i mean quieter then a a stock car car with an exhaust, im not sure how I feel about that yet.

Overall im very pleased, car runs well and it only took me a month and half to assemble but I have the pride of knowing I did it my way :-D.

Ah never had a misfire code, or limp mode.

Lessons learned
Im an idiot.
Car wont start with fuel pump wired backwards.
OBDII Scan tools can have you missing simple shit(if you car wont start they give alot of bullshit errors)
Car wont start with OBDII scan tool plugged in.
There is no issue with running 440c injectors.
Jegs looses packages alot.
Bouncing of the Rev Limiters causes flames to come out of the exhaust :-D.
Variable timing makes fuel maps look odd.
****************** Repair manual book one is the the most usefull shit *********************

To dos(there are alot)
Header wrap the DP
Turbo Blanket the Tubros
Vented hood
Increase the turbo feed to a 6 AN line before the Tee.
Change the 90 Degree drain on a turbo to a 45 (have to remove so much shit)
Put a gasket on the wastegate (dont ask)
Headgasket (PHR)
Fuel return line.
Wire tank pump to passenger heated seat(where is the connector for this)
3inch (maybe bigger) exhaust, or one 2.5 from each turbo
Pray to the 5sp transmission God.

so much more to do and learn.

WHEW, please excuse and misspellings.

Thanks to all my lexotic brothers for all the support and the random people I hit up for information.
  • Like
Reactions: somguy2u

2,033 Posts
congrats man looks good. with all these boosted Yellow IS300's rolling around the US and them not producing Yellow anymore people might start to think the yellow ones came with boost :lol:

882 Posts
Nice setup you got there. You definately stick out from the crowd. I wish I had money to do all that you did.

Penetration Specialist
23,688 Posts
Nice setup again man. It was nice meeting and talking to you at the TBKO BBQ. Very impressive that you went out on your own and did put that together yourself. Congrats and good luck with it!! :D

5,384 Posts
Discussion Starter · #8 ·
cHoCoKoKo said:
:eek: :p can you tell us about how much you spend?
Spent? if I subtracted mess ups around 9k. With a front mount cheaper hose might of been around 7500.

23,616 Posts
Looks like ass Sentinal.
All your turbo are belong to me.

5,384 Posts
Discussion Starter · #12 ·
SophieSleeps said:
Looks like ass Sentinal.
All your turbo are belong to me.
Its Sentinel!!! :whine: :lol: :lol:

4,019 Posts
Awesome man, congrates. looking good. :D

Premium Member
2,590 Posts
Nice Sentinal, great job. I'm so proud of you my boosted brotha. That HUD is pimp cooo 8) . Enjoy mang, you deserve it. Yeah, you need better flowing exhaust.. :p

5,384 Posts
Discussion Starter · #19 ·
w1d_0ut_a_LEX said:
Expected numbers???

Nice work... :D

Till I do a HG im hoping for 300-350 at 7 psi, Id be happy if at 6 psi and stock rear section id be at 280whp.

5,384 Posts
Discussion Starter · #20 ·
Fig said:
Nice work Sentinel! Doing it yourself rocks, now grind those welds down ;)

keep us posted with the performance info, I like the TT cars too, even if you do get more peak with a single.

Ha yeah I need too, my welding skills leave alot to be desired, I have a mig not a TIG which is what I really need. :whine:
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