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cutsom rear mount turbo

24347 Views 84 Replies 12 Participants Last post by  Buildin 97 TA
Another rear mount turbo thread..... it was coming anyway :) lol

well i thought id get some extra thoughts on this forum since the other forums tend to get stale from time to time.

current setup

98 trans am
stock 5.7L 346ci
stock cam
LS6 intake
LS6 valley
catch can
OBX LT headers
catted ypipe
stock A4 with 3200 stall
stock 10bolt 2.73 gears
racetronix fuel pump and hotwire
301RWHP 314RWTQ 13.9 1/[email protected] mph spinning damn near the whole way on 315 sumitomos lol gonna get my kumho XS tires on and air them up for the track and not the highway and then make some passes. also gotta figure out how to launch my car withot spinning so much
HP goals for turbo build is 550ish and no more then 10psi. 14 psi will be availible but ill stick to just the 10psi spring until i get the tune right.

now for the turbo build items, ive got pretty much everything except the cam kit, base tune, and hp tuners in my garage. I can at least get it on and set up to run before i do the cam and meth kit.

INTAKE
Cone filter tucked into wheel well
3” intake into turbo
2.5” charge piping
T-bolt clamps and reinforced silicon hose couplers
31x11x3 intercooler
BOV and pipe
LS6 intake manifold
LS6 valley pan
4 port vacuum manifold

ENGINE
Stock 5.7L LS1
Tick custom rear turbo cam 226/235 .605/.610 114+2
Tick supplied valve springs
Tick supplied pushrods
LS2 timing chain
Stock Heads (317 with LS9 gasket later for 9.8CR)
Comp cams Rocker trunion upgrade
ARP crank bolt
Head studs

EXHAUST
OBX LT headers
Catless 3” ypipe with OBX resonators
Stock I-pipe
Sts style T4 header pipe with 44mm wastegate port
3” after turbo resonator
2” Wastegate dump exhaust
3” turbine exhaust
4” corsa clone tips/3” inlets

TURBO SPECIFIC
ON3 T76 w/.81 AR (.96 later)
44MM wastegate 4psi spring (10psi spring for later) (76mm/65mm)
50mm BOV
AEM water/Meth injection kit with progessive controller. gonna set on at 4-5 and full on at 10psi

TRANSMISSION
Stock 4L60E
Revmax stage 5 billet cover 3200 stall
B&M trans cooler
12+ quarts of royal purple tans fluid (lol i had to add that in there... god that was expensive)
Glowshift trans temp gauge

OIL SYSTEM
LS6 oil pump
4an feed
Summit check valve
10an drain
4psi hobb switch to piezo buzzer alert
Gear scavenger oil pump
10an return line into oil pan

PCV SYSTEM
LS6 valley pan with PCV valve
Catch can
Check valve
Vent line ran to fresh air intake tube from valve spring cover

FUEL SYSTEM
Stock fuel rails
Racetronix 225 fuel pump and harness
Aeromotive boost referenced fuel pressure regulator with 3/8 line return
60lbs siemens injector

ELECTICAL
NGK Spark Plugs BKR7E-11 5791 gapped at .032
MSD wires
Stock coils

ENGINE MANAGEMENT
Innovate MTX-L wideband
Glowshift digital boost/vac gauge
Glowshift digital fuel pressure gauge
Frost base tuned (HP tuners later)
GM 2 bar MAP sensor
GM 85mm MAF sensor
IAT sensor in MAF used, using wire adaptor.

MISC ITEMS
GM 93-97 radiator cover
Glowshift 3 gauge a-pillar pod

if anyone sees or happens to know of something im missing please let me know. im pretty sure i have everything though but no ones perfect lol
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i don't think you've missed anything major, sounds pretty awesome

you sure you don't want to go front mount for all the work you're putting into it?
ive gone back an forth about it, but having the front mount would be way more work to fit. I have a UMI RR Kmemeber that would be a PITA to get a 3" dump pipe thru. ive always wanted to do a rear turbo on the car and as the years have gone by, people have been getting them to funtion better and better. so im going through with it.
looks like a fun build :rockon:
ill post pics up of everything as soon as i lay it out in the garage to mock it up. gotta have a few tings weled up and waiting on a few things in the mail to come in too.
Bone stock A4 trans and 550 hp, well, good luck



Bone stock A4 trans and 550 hp, well, good luck
I second this . You might really think on beefing up the auto . I'd hate for you to get all that done and pop the tranny .

Sounds great though . Defiantly post pics of the build !
If he's not running slicks the street tires will break loose before the trans snaps i would like to believe
^^^this is kinda my thinking. im on streeet tires and dont ever plan on running on drag radials. my 2.73 gears also keep my launchs pretty soft lol
i perfer softer launchs with violent rushes half way threw lol
i do eventually plan on a 12 bolt with some slightly shorter gears like 3.23s and a built up trans and up the stall from 3200 to 3600.
if it was me, i would build the forced induction setup and run it until the trans explodes, and it will explode, i dont care how well it smokes the tires on launch. just plan for it to happen and have your spare built sooner rather than later.

i ran a 700r4 once that was 'destined for destruction', slipping bad because of how much power i was making. i messed with springs and throttle body linkage so it was at WOT on the tv cable at like 2/3rds throttle.

kind of ghetto but that got rid of the slip real good.. and it kicked down way earlier, so it was always in a lower gear than it needed to be. it survived for AGES like that.

along those lines, you could always jack up line pressure a bit in your tune, i bet it'll borrow you some more time. you have nothing to lose as it wont live forever anyway.
got a few more things in the mail including an AEM meth kit to get it started. I pretty much can get this thing rolling. i gotta out source my welding unfortunatly. i wish i had my own welding machine but cant justify a $500+ MIG machine to my wife yet lol one day lol
so hey, those of you with AEM kits, what injector nozzle do you use? i know they have 3 for the kit and AEM uses a generic HP rating for the nozzles but i know you dont want to start out too big.
9
well i layed everything out just to see how it would kinda route until i can do it on the car. we have been experienceing some bad sandstorms in el paso so im holding off on this, that and getting the rest of my taxes so i have the extra funds for those unexpected items









just a few pics id throw up before i get it up on the car
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looking good
its getting there lol now just to get it on the car. hardest part in think is just getting the welding done. not sure how im gonna do it but ill figure it out.
3
got some welding done today



mocked it up and then high temp painted the inlet pipe
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so i have a few more things to report, ill take some pictures when its light out again lol
installed the boost gauge, fuel pressure gauge, wideband gauge, and vacuum manifold log. :) also fixed the wiring so that my trans temp gauge actually dims when i turn the head lights on.
was really simple actually once i mounted the gauges in the gauge pillar pod and simplified the wiring. i pre fabed it so that it goes in as a unit. all the red 12volt switch wires bundled together, all the ground wires bunded together, and all the headlight switch wires bunded. the only one thats gonna be a hassle later is the wideband, but i am glad i set it on the botton pod position. the data serial cable, 2 analog sources, and wideaband cable sit just under above the vent lol but it shuold be ok. im not using most of them yet except the wideband.
all i gotta do now is hook a wastegate and BOV to the manifold. i also hooked up the boost reference hose to the FPR. its not getting pressure yet lol but its all hooked up so when i get the turbo on, it will be there when i need it.
the boost gauge is only getting vacuum right now lol but its reading -11 at idle. im assuming thats normalish. it moves been i apply the throttle. not sure what, it moved too fast lol its digital so its quick.
the fuel pressure guage reads 0 for now lol no fuel going through the FPR yet lol but its registered at zero so thats cool lol. i need to hook that up so i can check the fuel pressure.
tomorrow ill hook up the wideband sensor so i can check and see what my AFR is.
the vacuum manifold kit was great! had all the fittings, different diameter hoses and barbs to do everything! got it right off the booster. for now the two other ports are blocked off until i hook up the wastegate and BOV. the meth kit will have to t off something. the BOV hose should be ok for that since it will be the closest to tie into for that.
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7
so i have a few more things to report, ill take some pictures when its light out again lol
installed the boost gauge, fuel pressure gauge, wideband gauge, and vacuum manifold log. :) also fixed the wiring so that my trans temp gauge actually dims when i turn the head lights on.
was really simple actually once i mounted the gauges in the gauge pillar pod and simplified the wiring. i pre fabed it so that it goes in as a unit. all the red 12volt switch wires bundled together, all the ground wires bunded together, and all the headlight switch wires bunded. the only one thats gonna be a hassle later is the wideband, but i am glad i set it on the botton pod position. the data serial cable, 2 analog sources, and wideaband cable sit just under above the vent lol but it shuold be ok. im not using most of them yet except the wideband.
all i gotta do now is hook a wastegate and BOV to the manifold. i also hooked up the boost reference hose to the FPR. its not getting pressure yet lol but its all hooked up so when i get the turbo on, it will be there when i need it.
the boost gauge is only getting vacuum right now lol but its reading -11 at idle. im assuming thats normalish. it moves been i apply the throttle. not sure what, it moved too fast lol its digital so its quick.
the fuel pressure guage reads 0 for now lol no fuel going through the FPR yet lol but its registered at zero so thats cool lol. i need to hook that up so i can check the fuel pressure.
tomorrow ill hook up the wideband sensor so i can check and see what my AFR is.
the vacuum manifold kit was great! had all the fittings, different diameter hoses and barbs to do everything! got it right off the booster. for now the two other ports are blocked off until i hook up the wastegate and BOV. the meth kit will have to t off something. the BOV hose should be ok for that since it will be the closest to tie into for that.

i think tomorrow while im under the car ill also start putting the oil pump in there. just to get it ready to hook it up. the less i have to do the better when the turbos ready to go on it.

heres the pictures i promised






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5
and the first test fit is a success! got the pieces all welded into place and ready for final installation





now to run some oil lines, mount the pump, connect the fuel return system, and run the intercooler and charge piping and we are in business
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looking good! looks close too, did you test fit the air filter?
alittle bit. i have a pipe that will be routing up insde that little plastic shield likw STS does now with their newer kits. i perfer to have my filter away from everything
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