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Safe - AFR's

Kdawgboostin33

By Kdawgboostin33,
in Engines & Forced Induction

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Kdawgboostin33 Collaborator

Kdawgboostin33

Posted
Posted

Hi Guys,

What would be a safe Air / Fuel Ratio for an RB25DET running 14PSI - Everyday?? I have been told that a safe cruise level is around 14.7 / 1. My current cruise setting is 11.5 / 1. Can this in time cause oil to wash from the bore and what other dangers would I be looking at?? Thanks in advance.....

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rs73 Grand Master

rs73

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I agree around 11.5 to 12.1 is the safest... anything above 12.5 on boost could mean trouble for the engine. on cruising not sure, but as long as no boost, i guess 14 is ok. 11 on cruise is way too rich, something is wrong man

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rs73 Grand Master

rs73

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Have you got white smoke comming out your exhaust ?  

If so, your ring lands are probaly on thier way out !

If he said car is using a bit of oil, so I reckon the exhaust smoke should have a bluish colour if it's burning oil. ring land issue too.. or perhaps oil seal on turbo, either way, better get it checked.

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The Alchemist Collaborator

The Alchemist

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I run 15:1 at light throttle on my GTR no problem at all. 40 to 42 degrees timing No problem. Once over 3600rpm though I increase it to 14:1, still 40 degrees timing too.

Boost> as per above posts :D

I think your car has a problem ....

Mike

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