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Pull the head off and have a look. Can't really blame the tuner until you know what went wrong. Even then good luck having them admit fault.

Driving with twice the amount of oil it's meant to have probably didn't help anything as well

Just doesnt make sence to me bro hes bot afmitting it i hust had the car at hes garage hes saying he pulled the timing out as much as he could and had it on safest tune but 24hrs later after dyno it drops a cylinder like wtf?

6th cylinders always run hotter as it's the last to get coverd in water..

?? its the shape of the intake... more air is going into the 6th cylinder due to the intake design..which means they typically run leaner...which means hotter.

Running apexi fc 18psi hes telling me all AFRS were perfect and timing was abit morw then standard!

Hes nowing sayin a blocked cat could f*k the tune (its been punched out and cleaned when exhaust came off)

6th injector could have blocked or not working properly?

I dont get that shoukd it not show up in anyway wow or form?

Hes saying it might have just been a warn cylinder and lost pressure? Bullshit the car was knocking on the fc after the tune and ao he pulled timing on it and atill was knocking

If an injector died you would have had a mad missfire, since no fuel is going into that cylinder.

If it was partially blocked however, it would still run, just excessively lean and under full boost that means burned valves/det/f**ked engine. Do you have a wideband o2 sensor by any chance? If you do did you notice it running leaner than it should?

6th cylinders always run hotter as it's the last to get coverd in water..

More a case of the one that runs the leanest due to manifold design.

Most workshops when flow testing injectors automatically put the largest flowing one on number 6 when dealing with RB26's as a precaution......

Running apexi fc 18psi hes telling me all AFRS were perfect and timing was abit morw then standard!

Hes nowing sayin a blocked cat could f*k the tune (its been punched out and cleaned when exhaust came off)

6th injector could have blocked or not working properly?

I dont get that shoukd it not show up in anyway wow or form?

Hes saying it might have just been a warn cylinder and lost pressure? Bullshit the car was knocking on the fc after the tune and ao he pulled timing on it and atill was knocking

Maybe it wasn't knocking on the dyno. If the maps were safe with no knock when he was tuning then it not really fair to blame the tuner. Sorry to hear the bad news, let us know how it goes.

Edited by ima_slap_joO

The cylinder didnt die nor f**k any valves the car starts idles and drives fun with. O hesitation just loss in performance and blows smoke.

Now what does this build need for it to never happen again i am not requiring some epic 1000hp build i just want a build that will not knock from a stupid bearing and will hold 350-400kws safely to drive when i want to thats what i want!!

Forged pistons,rods and acl bearings?

The fact that it has half the compression of the other cylinders means it's pretty much dead. Rip the head off and have a look at the damage. Can't really give any meaningful advice until you know what caused the damage

Removing the head won't tell you much about ring lands, and you've seriously busted a gut working on an in-situ engine.

You did a compression test and from those results, the logical next step is a leak down test.

From those results, I think it's a safe bet you'll be pulling the engine, but you need to follow the logical trouble shooting procedures to know where you're heading.

Im pulling the motor out i took it to tuners to double check my results and he cane to the same conclusion 6th cylinder piston ring, but what he can tel is what caused it an injector? A pwer fc fault? A bogged spark plug? Spike in boost we jist dont know

Injectors can be removed, numbered and flow tested.

Carefull analasis can hint/assist towards what happened on tear down, there are lots of hints like the color for the burn in the combustion chambers and spark plugs, Det marks etc....

If you are using an RB26 manifold and no individual injector trim then cylinders 5 and 6 WILL run lean, and it will only get worse as load increases!

Was any injector trim set up in the Power FC?

Remember if you don't have individual EGT sensors, then you are tuning based on the average of all 6 cylinders, so it is still possible to get a good AFR reading when cylinders 5 and 6 are running lean.

It just means that cylinders 1-4 are running richer than they need to be, and cylinders 5 and 6 aren't rich enough, which averages out to look OK.

In my tune the tuner phased in 3% more fuel to cylinder 5 and up to 6% more fuel to cylinder 6, as revs and MGP increases!

So if you didn't have injector trim on these cylinders, then that would explain why 6 was the first cylinder to pop!

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Great guys this is much help and i will explain this to my tuner once car is rebuilt and ready to go this has helped me understand rb26s more as im a 2jz man lol but thanks guys will be starting a build thread and askig for sole tips soon

I don't know much about Power FC and whether it can do injector trims per cylinder, but if you want some correction tables as a starting point let me know, and I will pull them out of my Link map.

Cheers,

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