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1995 EZ30 Coupe
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Discussion Starter · #121 ·
sick build! I was thinking of going rotated also but it seems like a ton of work.

Is there a reason youre going for blow through MAF instead of speed density?
Thanks dood! Honestly a rotated turbo is worth it just for the looks imo, but a FMIC was also something I wanted regardless. I did have to relocate many components and lay a ton of heat wrap/tape.

I use a piggyback with the stock ECU because I like the simplicity of it. I basically just adjust fueling and timing as needed for boost, the ECU worries about cold starts, dwell times, etc.
The only things my setup can't do is advance timing or increase the redline, and I should be able to accomplish both by hacking the ECU...
 

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Thanks dood! Honestly a rotated turbo is worth it just for the looks imo, but a FMIC was also something I wanted regardless. I did have to relocate many components and lay a ton of heat wrap/tape.

I use a piggyback with the stock ECU because I like the simplicity of it. I basically just adjust fueling and timing as needed for boost, the ECU worries about cold starts, dwell times, etc.
The only things my setup can't do is advance timing or increase the redline, and I should be able to accomplish both by hacking the ECU...
I'd go rotated but I'm not even sure if my current setup is 100% just yet, still need to register and tune it.

It sure does look fun and cleans up a bit of space around the intake manifold, i have a ton of stuff running through there.

What kind of piggyback are you running?
 

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Discussion Starter · #124 ·
What kind of piggyback are you running?
AEM FIC 6. After I added some resistors across the cam and crank input wires and zip tied the MAP sensor hose inside the unit, it's been working quite well. I just use a boost gauge and a wide band O2 to tune it, on deserted roads of course.
 

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Discussion Starter · #125 ·
Pics? May be worth a newer TB, more flow.
I definitely want a larger throttle body, but I really like the integrated IACV. I'd like to try porting the hell out of it and using a throttle blade from a larger TB.
 

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AEM FIC 6. After I added some resistors across the cam and crank input wires and zip tied the MAP sensor hose inside the unit, it's been working quite well. I just use a boost gauge and a wide band O2 to tune it, on deserted roads of course.
Nice! I wish I had enough cojones to try to tune myself. I've only gotten as far as injector scaling, idle, and deleting codes.
 

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Discussion Starter · #127 ·
Just cleared 1000 miles on the built motor, it's running great. I tried soldering in faster clock speed controllers to two different ecu's to get a higher redline, no go. I did get the higher idle and leaned out AFR's though. I ordered new controllers to try again later.
I also discovered a few things about boost control with a larger turbo. First is that exhaust gas pressure can easily overcome a manual boost controller and wastegate, at least at over double the wastegate spring pressure. Had to install a three port vacuum solenoid to allow boost to the top port of my wastegate to hold it shut until target boost. It's not proper but it works pretty well, with just a slight fluctuation at full boost that makes it sound like a doomsday device powering up.
87199

Second, I never guessed just how much difference a muffler can make. I have a full 3" exhaust, no cats, no resonators, to a fart can with a removable baffle. With the baffle in it's quiet enough to take to work early in the am, but it wont make more than about 10psi, any gear, any load. Baffle out, and it's a bit too loud for a comfortable daily. Combined with the solenoid, she screams right up to 20psi easily. Very enjoyable.
I relocated the MAF and gave it some heat tape.
87200

Seems to have made it less temperamental.
I need to figure out how to raise the redline as it won't quite hit 20psi in second, and my piggyback limits be to 25psi of boost. Those two things are all that hold me back now!
87201
 

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Discussion Starter · #128 ·
Interesting side note: my calculated compression ratio is.... 6.5ish to 1.

I gotta run more boost.
 

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Discussion Starter · #129 ·
I'm probably insane. I swapped out the GT35 last night because the external wastegate v-bands leak and I wanted more boost threshold.
Popped a TD04 back in there, and it sucks!
First it leaked like a sieve because I didn't have a clamp at the top of the turbo oil drain hose. Blowby blew oil all over the bottom of the turbo and up pipe, making a nice smokescreen. Then I kept popping a shoddy intercooler piping joint because my piping and everything else is 2.5" and the compressor output is 0.00000000000003" and my fabri-cobbled adapter is shité. I can only get it up to about 15psi, I'm guessing I'd need an aftermarket wastegate to fix that. It feels kinda fast at low rpms where I didn't have boost, but up top I'm expecting so much more.
Yup, back to the GT35!
 
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