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Max boost on stock engine, 440cc? TD06

5040 Views 13 Replies 5 Participants Last post by  MRQtwinturbo
Just installed a a td06 20G and greddy downpipe. Wanted to know what the max boost is I can run with this setup...

TD06 20G internal wastegate
greddy downpipe
ATS oil feed lines
Full CATLESS 3" exhaust
Walboro 255lph fuel pump
Bored ATS fuel rail (bored from 3mm to 8mm)
ATS FPR (50psi)
STOCK 440 injectors
TRD clutch
No EGR (JDM engine) about 48k miles
K&N intake
Trunk mounted intercooler

I have a AEM wideband, but have a pretty bad exhaust manifold leak, and a leak at the downpipe so dont think the AFR is right. But im running about 13-14psi and seen it get to about to about 12.7. Not sure if the exhaust leaks will cause the AFR to be more lean, or more rich. Just wanted to know about how much boost to run? I have a fresh ignition system. cap/rotor/NGK wires/NGK plugs, and even started using royal purple synthetic oil.

Thanks guys!
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First off, I'd worry more about fixing those exhaust leaks. There's really no point in adjusting anything on a car that's running improperly.

With stock intercooler and ecu you should be safe up to 15-16 psi. I wouldn't go past that, though, especially if you're already running that lean. Fix the leaks and get a good engine management system. Then tune it at a dyno and boost away.

Good luck!
I have a big trunk mount IC. Forgot to add that in the mods list.
even with supra 550s on my old setup i was at almost 95% duty cycle at 15 psi (HKS vpc and t3/ i'm running 780cc injectors and hks f-con)...i would invest in bigger injectors...better to have more fuel that not enough....
Was that stock rail, and stock fuel pressure? According to ATS having there ATS FPR makes a 440cc injector like a 480cc. I have that, plus a walboro pump and the bored rail.
i had the stock fuel rail bored to a dual feed.....i totally re-did my fuel system once i built the motor just to be safe to run more boost....also in case later on i wanted to go to upgrade to a gt series turbo....
Honestly.... your best bet is to go to the dyno and see what your air/fuel is. Have a competent tuner set your boost... and never look back.
Any of you guys have any burning oil smoke after a hard run? Im only pushing 12-13psi and seems the turbo is barely working not making the car pull hard. After 3rd gear I can see some smoke comming from the engine lid. Im guessing its comming from the manifold leak making it come up through the engine lid. Some people told me to go with a -3 oil feed line because the -4 that i have could cause some blow-by which sort of seems thats whats happening. I took the boost to 15 and it made a big difference compared to 2 psi less.

Also if i go to the dyno will these exhaust leaks make my car run rich/lean? What is the highest AFR i should be maxxing at? Im getting the downpipe gasket put on today to take care of that leak. Then the manifold leak will be more complicated which meens me taking the turbo back off......grrrr
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You need to fix all of your maintenance issues before you try and make more power. Get all of your leaks fixed. Replace all of your ignition components. Change your oil. Check your coolant... etc etc. Modifying an improperly running car is only going to make it run worse.
You will never have a proper tune until you fix the exhaust leak. Everything else is mute until then.Fix it and go from there. You will see a big difference after sealing the leak.
invest in wide band air/flow meter...they are reasonably priced nowadays...i have the innovative lc-1 kit and love it...
invest in wide band air/flow meter...they are reasonably priced nowadays...i have the innovative lc-1 kit and love it...
Damn! $400! I picked mine up last night.... brand new in box for $200 with the gauge. Gotta love people who are desperate to sell parts. :thumbup: How long have you had yours, Quang?
I did replace all my ignition components, and changed the oil. I use royal purple synthetic. I also have a AEM wideband installed, but with a slight downpipe leak, and manifold leak im not sure how accurate it would be.
russ....i've had mine about two years ago...can't remember how much i paid...
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