Going from a single turbo to twins
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From: Leicester,Massachusetts
Car: 1983 CHEVROLET CAMARO Z28
Engine: Forged 355 with a GT45 turbo
Transmission: TKO 600
Axle/Gears: built 4th gen rear with 3.27s
Going from a single turbo to twins
Well, I've decided to go from a single turbo setup to a twin turbo setup. Here is where I'm at right now(see pic). These are Master Power T70's with a .68 exh ar. Also I am waiting for a different set of turbo manifolds. I will post progress as it comes.
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From: Leicester,Massachusetts
Car: 1983 CHEVROLET CAMARO Z28
Engine: Forged 355 with a GT45 turbo
Transmission: TKO 600
Axle/Gears: built 4th gen rear with 3.27s
Re: Going from a single turbo to twins
They came from a friends turbocharged 82 Z28. I will be running 14 psi with these. Sadly he is selling the car as a rolling chassis.
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From: Leicester,Massachusetts
Car: 1983 CHEVROLET CAMARO Z28
Engine: Forged 355 with a GT45 turbo
Transmission: TKO 600
Axle/Gears: built 4th gen rear with 3.27s
Re: Going from a single turbo to twins
First peice of the puzzle has arrived. I'm quite impressed with the quality of these headers. My only issue is with the Trick Flow G1 heads I will need to clearance the bottom of the flanges a little bit so I may change the spark plugs with ease.
I am still figuring out where I will place the turbos .
I am still figuring out where I will place the turbos .
Last edited by Badass355ciz28; Nov 9, 2015 at 07:15 PM.
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From: Pittsburgh PA
Car: 89 Iroc-z
Engine: 555 BBC Turbo
Transmission: TH400
Axle/Gears: MWC 9” 3.00
Re: Going from a single turbo to twins
May be best to get a tube kmember and look to do plug changes from underneath lol its how i do all of mine on my race car and half the plugs in my stock manifold 91 z28
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iTrader: (17)
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From: Leicester,Massachusetts
Car: 1983 CHEVROLET CAMARO Z28
Engine: Forged 355 with a GT45 turbo
Transmission: TKO 600
Axle/Gears: built 4th gen rear with 3.27s
Re: Going from a single turbo to twins
Already have a Pro Fab k member and just spent the past 30 minutes placing the turbos where I want and also figuring how the down pipes were gonna be run. 
Also here is a better picture of the headers mocked up

Also here is a better picture of the headers mocked up
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iTrader: (17)
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From: Leicester,Massachusetts
Car: 1983 CHEVROLET CAMARO Z28
Engine: Forged 355 with a GT45 turbo
Transmission: TKO 600
Axle/Gears: built 4th gen rear with 3.27s
Re: Going from a single turbo to twins
not sure why the picture is sideways
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Thread Starter
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iTrader: (17)
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From: Leicester,Massachusetts
Car: 1983 CHEVROLET CAMARO Z28
Engine: Forged 355 with a GT45 turbo
Transmission: TKO 600
Axle/Gears: built 4th gen rear with 3.27s
Re: Going from a single turbo to twins
Orr89Rocz how does your down pipes route? any pictures ?
Joined: Sep 2003
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From: Pittsburgh PA
Car: 89 Iroc-z
Engine: 555 BBC Turbo
Transmission: TH400
Axle/Gears: MWC 9” 3.00
Re: Going from a single turbo to twins
My headers leave a gap between the rear cylinders so i can get a downpipe up aand over the valve covers and down between cylinders
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iTrader: (17)
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From: Leicester,Massachusetts
Car: 1983 CHEVROLET CAMARO Z28
Engine: Forged 355 with a GT45 turbo
Transmission: TKO 600
Axle/Gears: built 4th gen rear with 3.27s
Re: Going from a single turbo to twins
Post up some pictures if you have any. I am gonna be asking you a few questions now and then so I hope you don't mind.
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iTrader: (17)
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From: Leicester,Massachusetts
Car: 1983 CHEVROLET CAMARO Z28
Engine: Forged 355 with a GT45 turbo
Transmission: TKO 600
Axle/Gears: built 4th gen rear with 3.27s
Re: Going from a single turbo to twins
Thank you...gives me some sort of idea My headers are setup a little differently than yours.
Joined: Sep 2003
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From: Pittsburgh PA
Car: 89 Iroc-z
Engine: 555 BBC Turbo
Transmission: TH400
Axle/Gears: MWC 9” 3.00
Re: Going from a single turbo to twins
If you have the room go down and under k member to keep heat out of the engine bay
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From: Leicester,Massachusetts
Car: 1983 CHEVROLET CAMARO Z28
Engine: Forged 355 with a GT45 turbo
Transmission: TKO 600
Axle/Gears: built 4th gen rear with 3.27s
Re: Going from a single turbo to twins
I do have room under each header and could probably go under more near the k member.
Does your exhaust go all the way to the back or does it cut off under the car tucked in the tunnel?
Does your exhaust go all the way to the back or does it cut off under the car tucked in the tunnel?
Joined: Sep 2003
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From: Pittsburgh PA
Car: 89 Iroc-z
Engine: 555 BBC Turbo
Transmission: TH400
Axle/Gears: MWC 9” 3.00
Re: Going from a single turbo to twins
Street exhaust y's by the cat location and runs all way back to rear bumper
My last track outing i dropped exhaust and ran downpipes out from behind the front tires
My last track outing i dropped exhaust and ran downpipes out from behind the front tires
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iTrader: (17)
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From: Leicester,Massachusetts
Car: 1983 CHEVROLET CAMARO Z28
Engine: Forged 355 with a GT45 turbo
Transmission: TKO 600
Axle/Gears: built 4th gen rear with 3.27s
Re: Going from a single turbo to twins
That is probably what I will do since I just did 4'' exhaust from the cat location all the back last summer.
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iTrader: (17)
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From: Leicester,Massachusetts
Car: 1983 CHEVROLET CAMARO Z28
Engine: Forged 355 with a GT45 turbo
Transmission: TKO 600
Axle/Gears: built 4th gen rear with 3.27s
Re: Going from a single turbo to twins
Hope so. I am only going to run 14 psi once everything is done for awhile.
Joined: Jul 1999
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From: SALEM, NH
Car: '88 Formula
Engine: LC9
Transmission: 4L60E
Axle/Gears: 3.89 9"
Re: Going from a single turbo to twins
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iTrader: (17)
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From: Leicester,Massachusetts
Car: 1983 CHEVROLET CAMARO Z28
Engine: Forged 355 with a GT45 turbo
Transmission: TKO 600
Axle/Gears: built 4th gen rear with 3.27s
Re: Going from a single turbo to twins
big money for that kit too lol
Joined: Sep 2003
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From: Pittsburgh PA
Car: 89 Iroc-z
Engine: 555 BBC Turbo
Transmission: TH400
Axle/Gears: MWC 9” 3.00
Re: Going from a single turbo to twins
Well i am anti fender exit. Gotta run pipes out the back of the bay or the front and curl to the back. Thats it. Mine looks like alot of plumbing but where else can you go?
Redoing this i would attempt to go down in front of the car under or thru kmember.
I dont know how much power a manifold would support. Banks claimed alot of power on that but all the serious 1200+ hp guys run headers that i know of.
On a street car that wants under a 1000, i suppose they can work great but NOT worth the money imo for banks. I would fab my own log
Joined: Jul 1999
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From: SALEM, NH
Car: '88 Formula
Engine: LC9
Transmission: 4L60E
Axle/Gears: 3.89 9"
Re: Going from a single turbo to twins
I dont know how much power a manifold would support. Banks claimed alot of power on that but all the serious 1200+ hp guys run headers that i know of.
On a street car that wants under a 1000, i suppose they can work great but NOT worth the money imo for banks. I would fab my own log
On a street car that wants under a 1000, i suppose they can work great but NOT worth the money imo for banks. I would fab my own log
-- Joe
Joined: Sep 2003
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From: Pittsburgh PA
Car: 89 Iroc-z
Engine: 555 BBC Turbo
Transmission: TH400
Axle/Gears: MWC 9” 3.00
Re: Going from a single turbo to twins
Pics of banks thirdgens? I am very curious how you fit any downpipe on driver side. Booster/master and steering shaft make it difficult. 3" minimum pipe for big hp
More the merrier lol
And you dont need all the heat in the world to make turbos work. Proper header design still has velocity and more directed flow. Manifolds are not efficient flow devices. They work but the flow isnt clean. Can easily have cylinder to cylinder contamination/reversion effects
There is a place for them in tight spots but driver side on twin setups is always a problem with exhaust routing no matter what setup you use
More the merrier lol
And you dont need all the heat in the world to make turbos work. Proper header design still has velocity and more directed flow. Manifolds are not efficient flow devices. They work but the flow isnt clean. Can easily have cylinder to cylinder contamination/reversion effects
There is a place for them in tight spots but driver side on twin setups is always a problem with exhaust routing no matter what setup you use
Joined: Jul 1999
Posts: 12,093
Likes: 126
From: SALEM, NH
Car: '88 Formula
Engine: LC9
Transmission: 4L60E
Axle/Gears: 3.89 9"
Re: Going from a single turbo to twins
Pics of banks thirdgens? I am very curious how you fit any downpipe on driver side. Booster/master and steering shaft make it difficult. 3" minimum pipe for big hp
More the merrier lol
And you dont need all the heat in the world to make turbos work. Proper header design still has velocity and more directed flow. Manifolds are not efficient flow devices. They work but the flow isnt clean. Can easily have cylinder to cylinder contamination/reversion effects
There is a place for them in tight spots but driver side on twin setups is always a problem with exhaust routing no matter what setup you use
More the merrier lol
And you dont need all the heat in the world to make turbos work. Proper header design still has velocity and more directed flow. Manifolds are not efficient flow devices. They work but the flow isnt clean. Can easily have cylinder to cylinder contamination/reversion effects
There is a place for them in tight spots but driver side on twin setups is always a problem with exhaust routing no matter what setup you use
I'm not saying headers don't work, obviously you guy's are in the 8s and streetable. I'm saying that it's not for me. Personal choice.
-- Joe
Joined: Jul 1999
Posts: 12,093
Likes: 126
From: SALEM, NH
Car: '88 Formula
Engine: LC9
Transmission: 4L60E
Axle/Gears: 3.89 9"
Joined: Sep 2003
Posts: 25,895
Likes: 429
From: Pittsburgh PA
Car: 89 Iroc-z
Engine: 555 BBC Turbo
Transmission: TH400
Axle/Gears: MWC 9” 3.00
Re: Going from a single turbo to twins
Wow no idea how that driver side gets thru. Looks small tho, 2.5" pipe? Turbos are small to
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From: Panama City FL
Car: 87 Iroc
Engine: Turbocharged 5.7 Pro-Fl-XT
Transmission: 700R4 for moment
Axle/Gears: 3.25 9 inch
Re: Going from a single turbo to twins
I can see why everyone just does front exits on twins. I may be fighting this battle too soon if I elect to do twins. I'm not afraid to fire up my plasma cutter any more though!
Joined: Jul 1999
Posts: 12,093
Likes: 126
From: SALEM, NH
Car: '88 Formula
Engine: LC9
Transmission: 4L60E
Axle/Gears: 3.89 9"
Re: Going from a single turbo to twins
T04b's. Im unsure of exhaust size, as those parts were gone by the time I bought the car. I do know that in the mid 90s the car made around 500rwhp on pump gas through a th400/9" and cats. Passed emissions and ran fairly low boost with no intercooler. Was fast at the time. Lol
Joined: Sep 2003
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From: Pittsburgh PA
Car: 89 Iroc-z
Engine: 555 BBC Turbo
Transmission: TH400
Axle/Gears: MWC 9” 3.00
Re: Going from a single turbo to twins
Yeah they are small but guess could work lol 500 thru a th400 is no joke
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From: Leicester,Massachusetts
Car: 1983 CHEVROLET CAMARO Z28
Engine: Forged 355 with a GT45 turbo
Transmission: TKO 600
Axle/Gears: built 4th gen rear with 3.27s
Re: Going from a single turbo to twins
I just ordered a couple 90* elbows to join the CX Racing T4 adapter housings that I am expecting for the weekend. I will probably have 1/2 of the hot side done by Sunday. Keeping my fingers crossed.
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From: Leicester,Massachusetts
Car: 1983 CHEVROLET CAMARO Z28
Engine: Forged 355 with a GT45 turbo
Transmission: TKO 600
Axle/Gears: built 4th gen rear with 3.27s
Re: Going from a single turbo to twins
I got some more progress done tonight with the 90 degree bends and the flanges off of the headers. I also decided to remove the center section of the radiator support since I am making a little more clearance for everything including a new radiator.
Last edited by Badass355ciz28; Nov 11, 2015 at 11:29 PM.
Thread Starter
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iTrader: (17)
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From: Leicester,Massachusetts
Car: 1983 CHEVROLET CAMARO Z28
Engine: Forged 355 with a GT45 turbo
Transmission: TKO 600
Axle/Gears: built 4th gen rear with 3.27s
Re: Going from a single turbo to twins
These will be waiting for me today when I get home.....
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From: Leicester,Massachusetts
Car: 1983 CHEVROLET CAMARO Z28
Engine: Forged 355 with a GT45 turbo
Transmission: TKO 600
Axle/Gears: built 4th gen rear with 3.27s
Re: Going from a single turbo to twins
Here are a few more pictures from tonight's progress.
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From: Leicester,Massachusetts
Car: 1983 CHEVROLET CAMARO Z28
Engine: Forged 355 with a GT45 turbo
Transmission: TKO 600
Axle/Gears: built 4th gen rear with 3.27s
Re: Going from a single turbo to twins
Another
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From: Leicester,Massachusetts
Car: 1983 CHEVROLET CAMARO Z28
Engine: Forged 355 with a GT45 turbo
Transmission: TKO 600
Axle/Gears: built 4th gen rear with 3.27s
Re: Going from a single turbo to twins
Last one for tonight.
Joined: Jul 1999
Posts: 12,093
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From: SALEM, NH
Car: '88 Formula
Engine: LC9
Transmission: 4L60E
Axle/Gears: 3.89 9"
Re: Going from a single turbo to twins
What is the plan to brace the turbos? My experience with those vbands is they leak if any stress is put on them.
Looks great though. Nice clean routing.
Downpipes going under the k-member or over? 2.5" ?
-- Joe
Looks great though. Nice clean routing.
Downpipes going under the k-member or over? 2.5" ?
-- Joe
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iTrader: (17)
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From: Leicester,Massachusetts
Car: 1983 CHEVROLET CAMARO Z28
Engine: Forged 355 with a GT45 turbo
Transmission: TKO 600
Axle/Gears: built 4th gen rear with 3.27s
Re: Going from a single turbo to twins
I will also be making a new lower radiator support and installing a new radiator. 28"x16" to fit nicely in there.
the v bands have a lip on one side which fits into the other end which should eliminate any leaks. I haven't had any issues with the v bands on my single setup which didn't leak.
Also I will be doing 3" down pipes down between the engine and k member and hope to merge them into my 4" cat back exhaust that I just did last year.
Thread Starter
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iTrader: (17)
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From: Leicester,Massachusetts
Car: 1983 CHEVROLET CAMARO Z28
Engine: Forged 355 with a GT45 turbo
Transmission: TKO 600
Axle/Gears: built 4th gen rear with 3.27s
Re: Going from a single turbo to twins
I took half an hour to cut and install the upper radiator support. I am hoping to do the lower support later this evening. Once I get the new radiator it should tuck in very nicely.
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iTrader: (17)
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From: Leicester,Massachusetts
Car: 1983 CHEVROLET CAMARO Z28
Engine: Forged 355 with a GT45 turbo
Transmission: TKO 600
Axle/Gears: built 4th gen rear with 3.27s
Re: Going from a single turbo to twins
At my house in my garage. So nice to have a garage now.
Joined: Jul 1999
Posts: 12,093
Likes: 126
From: SALEM, NH
Car: '88 Formula
Engine: LC9
Transmission: 4L60E
Axle/Gears: 3.89 9"
Thread Starter
Supreme Member
iTrader: (17)
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From: Leicester,Massachusetts
Car: 1983 CHEVROLET CAMARO Z28
Engine: Forged 355 with a GT45 turbo
Transmission: TKO 600
Axle/Gears: built 4th gen rear with 3.27s
Re: Going from a single turbo to twins
I moved into my house almost 2 yrs ago.
Joined: Jul 1999
Posts: 12,093
Likes: 126
From: SALEM, NH
Car: '88 Formula
Engine: LC9
Transmission: 4L60E
Axle/Gears: 3.89 9"
Thread Starter
Supreme Member
iTrader: (17)
Joined: Nov 2005
Posts: 1,104
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From: Leicester,Massachusetts
Car: 1983 CHEVROLET CAMARO Z28
Engine: Forged 355 with a GT45 turbo
Transmission: TKO 600
Axle/Gears: built 4th gen rear with 3.27s
Thread Starter
Supreme Member
iTrader: (17)
Joined: Nov 2005
Posts: 1,104
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From: Leicester,Massachusetts
Car: 1983 CHEVROLET CAMARO Z28
Engine: Forged 355 with a GT45 turbo
Transmission: TKO 600
Axle/Gears: built 4th gen rear with 3.27s
Re: Going from a single turbo to twins
As promised I was able to fab up and complete the lower support as well. I am now waiting on a box of 3" tubing from WWW.Mandrelbends.Com.
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Car: 89 RS 89 iroc 87 firebird
Engine: 3.1 Turbo/ 355 twin turbo
Transmission: a4 w/ 4500 stall/ a4 / t5
Axle/Gears: strange s60 /w 3:42's
Re: Going from a single turbo to twins
what do u think of those cast elbows?, was thinking about going the same route this winter when i go back to twins
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iTrader: (17)
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From: Leicester,Massachusetts
Car: 1983 CHEVROLET CAMARO Z28
Engine: Forged 355 with a GT45 turbo
Transmission: TKO 600
Axle/Gears: built 4th gen rear with 3.27s
Re: Going from a single turbo to twins
Very nice quality. $160.00 for the pair with all the hardware shipped
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From: Utah
Car: 89 RS 89 iroc 87 firebird
Engine: 3.1 Turbo/ 355 twin turbo
Transmission: a4 w/ 4500 stall/ a4 / t5
Axle/Gears: strange s60 /w 3:42's









