Rear Mount Turbo "Built" Thread

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Brew Q
Posts: 322
Joined: Mon May 06, 2013 3:28 pm
Car: '92 Q45 91k miles, '05 FX35
past: '99 740i (r.i.p.), '92 Maxima SE, '89 Maxima SE, '04 FX35
Location: Bryan / College Station, Texas

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This has been a while in the making, but I feel like it's close enough now to being finished to finally get a thread going.

The car:
92 G50/ Q45 with 95k miles on it.
This photo was taken by the previous owner, A LOT has been done since then, both on the maintenance side first and of course the rear mount set up.
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The exterior and the interior are in mint condition, plus a wheel and tire combo that may be worth what the car's worth, :chuckle: Being a life long Nissan enthusiast and recently getting into RWD V8's, I was in love.

I met sijoko last year and started talking... after a lot of communication back and forth, I ended up having him do the repair work and then we snowballed into the rear mount set up from there. So I have to give credit where it's due. I was plenty busy with work and life was overly complicated, so the Q was dropped off last fall with him. Not only did he have the resume to do it (having built a turbo Q), he's an ASE master tech that has owned 3 or 4 Q's (currently 1, the turbo beast). I had lots of ideas and so did he, but he's brought them to life and made them reality.

Before the build got started the following had to be done:
-fuel pump
-all 8 injectors replaced with cleaned and flow tested phase 2 injectors - Deatschwerks did the work on them and they flowed VERY close to each other (I was amazed)...don't have the numbers in front of me though.
-rear main seal, oil pan, valve covers and now resealing the timing cover :crazy:
-spark plugs, 1 step colder
-O2 sensors
-Trans Cooler
-front and rear sway bar bushings and end links (plus installing a rear sway bar courtesy of maxnix) Thank you sir!
-steering rack boots and bushings
-Master cylinder
-trans mount, replaced with a nismo unit (it's beefier)
-subframe spacers
-replaced stock rad fan with a Z32 fan (direct replacement)
-replaced motor mounts with heavy duty ones from Xcessive (urethane)

I know I'm leaving something out, but the show must go on. :toast:

Xcessive Motor Mounts
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installed, sorry for cell phone pic (I'll replace it with a better one later)
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Fitting the I/C... it's bigger than it looks. 4" thick, not quite as big as the one on sijoko's car, but installing it like this, we didn't have to cut the bumper support completely in half. Plus the 1st gen G50 has a tiny tiny area to put an intercooler in.

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Who needs windshield wiper fluid when you have methanol! :mike

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BEGI FMU (aka FPR) -it sees vacuum (now boost) and adjusts the fuel pressure up accordingly. Basically a rising rate regulator. Plus the guy that started BEGI is an Aggie, Whoop! FYI, I'm an Aggie as well.

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factory airbox goes buhbye!

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fleabay turbo - this is a chinese GT45 clone. A ton of V8 guys run this exact one and from the seller I bought from (and for 10's of thousands of miles at much higher boost). 69mm turbine side if I remember right...twin scroll, which will allow us to do something very cool and creative... this photo is from months ago, so yes heat shields have been added, the trunk looks completely different (a lot has been added to it as well).

The beauty of having the turbo half into the trunk is you can't see it from behind the car or next to it.

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A rear oiling system (separate from the motor), scavenge pump, reservoir, oil pressure gauge... (more pics on these later), but this is the pump we went with. It's very quiet, I can't even hear it at idle and the car isn't loud by any means. It's actually quieter now than before. Except at WOT :woot: Their Spartan series pump is really loud and I wouldn't recommend it at all. This one is awesome, plus fins for added cooling. We'll have an oil cooler on the rear end though to extend the pumps life, especially in the summer.

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Test fitting the exhaust before paint and header wrap, the more heat you keep in, the faster the spool!

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Homemade Quick Spool Valve
Here's the stainless piping after being painted. I know what you're thinking. Why the hell is there a wastegate pre-turbo? I read about quick spool valves last year some time and got sijoko in on it. Others have done exactly what sijoko has fabbed up - half the turbo is fed air from half of this exhaust piping until it reaches a predetermined psi. We'll set it somewhere in the middle of actual boost setting - probably around 3 or 4 psi. Then when the wastegate opens both sides of the twin scroll are fed air. So instead of a laggy big turbo, the car starts building boost in the low 2k rpms. It should also help driveability (smooth transition of power), but more power and much sooner.

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Boost controller by Innovate: it's a very nice unit, that gives multiple readouts. It doubles as a wideband reading A/F ratios constantly. Here it is mounted kind of like a cell phone, which I think came out pretty nice. I can always add a couple more gauges when I do a cd/mp3 player later.

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There are a lot more pictures and the car is running now, and very fast at just 3.5psi, but after the timing chain cover is resealed and a cheap boost controller is added to the quick spool valve (allowing us to find the sweet spot in when the 2nd wastegate unleashes the beast); we'll up the boost a bit, maybe 6 or 7 psi and see what she can do. :woot:

In another week or 2 I'll get some pics up of the rear oiling system, exhaust tip and a few other bits.

In 3 weeks I'll make a video or 2 to share :mike As you can tell, I'm stoked to drive this thing and to see it finish. Of course its a labor of love and $, there are still other things to do:

a built transmission with higher stall TC
lightweight 1 piece driveshaft
akebono brakes
cooling system upgrade, big radiator
bigger tires once the Mich Pilots in the rear are toast

a thread that delivers! :toast:
Last edited by Brew Q on Tue Jun 23, 2015 10:52 am, edited 1 time in total.


qship96
Posts: 6624
Joined: Sun Nov 24, 2002 11:31 am
Car: 1996 Q45

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I know nothing about turbo installation,but am wondering what is the reason to install it in the rear vs under the hood like most factory installs?

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Brew Q
Posts: 322
Joined: Mon May 06, 2013 3:28 pm
Car: '92 Q45 91k miles, '05 FX35
past: '99 740i (r.i.p.), '92 Maxima SE, '89 Maxima SE, '04 FX35
Location: Bryan / College Station, Texas

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take a basketball, now try to fit it under the hood of your Q somewhere. Front mount can be done, but requires a ton of work, custom headers etc. If done right, rear mount doesn't have any drawbacks really.

branscoset
Posts: 73
Joined: Sun Feb 15, 2015 6:42 pm
Car: 1991 Q45 on coil overs and 18" 350z rims

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When you are done, come up to Oregon and build mine.

no but seriously, looking good. I am jelly

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Q451990
Moderator
Posts: 11477
Joined: Tue Jul 23, 2002 8:21 am
Car: 1990 Q45 - 118K, 2022 Toyota 4 Runner, 2004 Frontier M/T - 108K, 2012 Xterra (Mom's), 2023 Rogue (Inlaws)
Location: Columbia, SC
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Very nice looking setup - sijoko's work is impressive! I can't wait for videos. :chuckle:

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Wiggler
Posts: 222
Joined: Mon Jun 25, 2012 11:12 am
Car: "WHITE BOYS CLUB"
1999 Wht Toyota Avalon XLS 200k!! (CHUBBS)
1999 Wht Infiniti Q45t 102K (TANK)
2001 Wht Subaru Forester 115k (JUNIOR)
Owner: Funny, BROWN, Bald South Asian
Location: North westsiieede! San Antonio, TX

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Interpersonal differences aside, the first responder to this thread has a point about the turbo being under the hood. Putting it under the hood right next to the engine always equals better efficiency. That being said, due to the plumbing issues mentioned, the rear mount method is probably the only feasible option for these cars. I guess storing cold beer in the trunk has now become a downside to this project. :) FGY-33's have a little more space in the engine bay, and I pondered the idea at Tim Duncan's speed shop here in SA, until other financial things came up.

Jttoka
Posts: 42
Joined: Fri Jun 19, 2015 8:37 am
Car: '99 Infiniti Q45t
'03 Audi Allroad
'08 Toyota Yaris
'89 Toyota MR2 Supercharged
Location: So Cal California

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Very nice, I love the smell of burning rubber.

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Brew Q
Posts: 322
Joined: Mon May 06, 2013 3:28 pm
Car: '92 Q45 91k miles, '05 FX35
past: '99 740i (r.i.p.), '92 Maxima SE, '89 Maxima SE, '04 FX35
Location: Bryan / College Station, Texas

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now time for a homebrew!

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