12ht how much boost is safe

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Boost + egt + lambda = safe

You can have low boost and be unsafe if fuel is not tuned correctly.

Some can say factory turbo is safe up to 14psi but what does that actually really mean? How safe and why?
 

rideglobally

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Boost isn't the issue, fuel is.
Boost + egt + lambda = safe

You can have low boost and be unsafe if fuel is not tuned correctly.

Some can say factory turbo is safe up to 14psi but what does that actually really mean? How safe and why?
My fuel is adjusted to the maximum, no smoke. I have a pre turbo egt probe and intercooler. Can I run it at 14psi boost all day long if I keep my EGT at 1200F. Can I blow the head gasket running too much boost?
 
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My fuel is adjusted to the maximum, no smoke. I have a pre turbo egt probe and intercooler. Can I run it at 14psi boost all day long if I keep my EGT at 1200F. Can I blow the head gasket running too much boost?
Get a wideband and see what your fuel/ratio is to be sure and fine tune correctly.

anywhere between 19:1 to 22:1 is ideal.

Some say 20:1 is the ideal target.
 

AussieHJCruza

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14 psi boost on cruise isn't an issue. My HDJ80 did hours on end at 20 psi cruising, pulling a decent trailer in mid 30C heat.
Fuel is the issue, if your pump hasn't been modified, you'll run out of fuel at circa 18 psi of boost on the 12HT
 

rideglobally

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Get a wideband and see what your fuel/ratio is to be sure and fine tune correctly.

anywhere between 19:1 to 22:1 is ideal.

Some say 20:1 is the ideal target.
I am researching this. Where do you install a wide band sensor on a 12ht and which one are you using?
Boost isn't the issue, fuel is.

Get a wideband and see what your fuel/ratio is to be sure and fine tune correctly.

anywhere between 19:1 to 22:1 is ideal.

Some say 20:1 is the ideal target.
I have search the internet and this forum I have not found anything on installing a wideband sensor on a 12ht engine.
 
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You can weld a bung anywhere on your downside exhaust some where in the middle after turbo

A Wideband is not specific to Vehicle

Or you can use a clamp on solution they make different sizes. Many companies to choose from. 1-3/4"-2" Clamp-On Wideband Oxygen Sensor Bung Adapter - https://www.glowshiftdirect.com/1-3-4-2-clamp-on-wideband-oxygen-sensor-bung-adapter/

I like Banks power so I’m planing to get there idash datamonster with no OBD support. Because it’s a multi gauge and has data logging on a SD card. But I like the idea of having egt/boost/oil temps and more in one gauge.

But glowshift and AEM make a o2 Wideband

Inovative motor sports also has a clip on solution you clip on your tail pipe and u can use to dyno tune. It’s more of a temporary install use.

Pretty sure any gauge will do. As long as it’s a Bosch lsu 4.9 Wideband sensor.
 
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Good link here showing 12ht dyno graphs and Potential gains
 

rideglobally

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You can weld a bung anywhere on your downside exhaust some where in the middle after turbo

A Wideband is not specific to Vehicle

Or you can use a clamp on solution they make different sizes. Many companies to choose from. 1-3/4"-2" Clamp-On Wideband Oxygen Sensor Bung Adapter - https://www.glowshiftdirect.com/1-3-4-2-clamp-on-wideband-oxygen-sensor-bung-adapter/

I like Banks power so I’m planing to get there idash datamonster with no OBD support. Because it’s a multi gauge and has data logging on a SD card. But I like the idea of having egt/boost/oil temps and more in one gauge.

But glowshift and AEM make a o2 Wideband

Inovative motor sports also has a clip on solution you clip on your tail pipe and u can use to dyno tune. It’s more of a temporary install use.

Pretty sure any gauge will do. As long as it’s a Bosch lsu 4.9 Wideband sensor.
Thank you, very helpful I will do some googling to understand more. After the wideband sensor is installed I would need to take it to a shop to adjust air fuel ratio. Correct or is there a video to show how to make this adjustment on a 12ht engine?thank you
 
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strange not sure why Facebook links don’t work for you. Or on IH8MUD But here is a screenshot.

ABDA5DE8-AAC3-417B-96BC-9CDC005BE6A9.png
 
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nothing wrong with my post I have checked on another computer you have to click the FB logo on the top right to open the link

Thanks I cannot open the link.
1664478827789.png
 

rideglobally

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strange not sure why Facebook links don’t work for you. Or on IH8MUD But here is a screenshot.

View attachment 3127148

I don’t have the MLS gasket, 30% injectors, I have the 1st generation Gturbo and over the engine intercooler. I tried contacting ads injectors but they are very busy. I don’t need to run 21psi boost, I will be happy with 14 to 16 psi. I just recently replaced my head gasket with OEM gasket.
 
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Why don’t you contact G-turbo maybe they can give you a ball park. I know others who got a tuning guide from them too.
 
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So curious as to adding 30% injectors, opening fuel all the way, etc. Finding MLS head gasket for 12HT can be problematic
for some, but is one necessary? What happens to fuel economy driving at normal speeds but with a loaded cruiser since
trying to reach max hp/nm isn't necessarily the goal for most. @Behemoth60 maybe you can add something, thx
 
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