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i'm with anthony there....

I can't see how the plenum that has been proven on 2 previous builds can have had such catastrophic results in just a few dyno runs.

when you think of some of the abortion cut and shut plenums that people manage to run on RB's without this happening it's hard to imagine it having such an effect unless it was over a few thousand km IMHO

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Cmon dude, flowing the intake? It's a motor that now has low comp due to an internal failure. It's pointless, and even if it was the manifold, how would you link it to a failure like low comp? Doesn't make sense.

You should be able to see signs of det with a bore scope. Even if the crown has nothing, it has low comp which means rings, which means the bore will have drag marks all over it where the rings lands have failed.

When I said clearances I said probably, which means it may or may not be that. Just about every second failure I have seen has been either:

1. Incorrect ring clearances

2. Incorrect bearing clearances

I would put money on it being either of the above, pending it's a well known tuner, who of course ran it up himself.

It's pretty uncommon to see ring lands fail (break) on forged pistons and detonation can't always be seen on the top of the piston, or the ring, with a bore scope or even with the piston in your hand.

There's detonation that causes pitting on the piston, then there's detonation that causes hammering of the pin bush, pin bore and big end bearing.

I agree that flowing the plenum is a waste of f**king time though. What kind of BS is that? Seriously

They informed me they put a borescope down the low comp cylinders and they had signs of Det and damaged bores on my already 87mm bored block.

I have heavily researched hard running in methods etc.

Now the tuners run in method was

Fire engine, free rev and blipping throttle under 50% till at temp, shut off engine check leaks etc, let it cool down, load it on the dyno and sit it at about 90kmh in 4th gear under medium load lowish boost for the 10kays.

I was under the impresion a good ring bed in required vartied loads, revs and engine braking?

On a fresh as fresh engine with good ring bed in what kind of cylinder pressures should be expected?

110psi for cylinders 3-6 seems low to me.

I have looked into many an engine with bore scopes and if he says he can clearly see theres damage/marks on the bores, i can assure you the top ring land has grabbed on the Inlet side of the piston... Ask your tuner how much timing he pulled out of the tune (which was for the old engine!!!).... From what u have said he changed nothing before doing a full power run on more boost than was requested... If you can get him on record (signed doc) that states he didnt change/do anything to tune before the run he's toast if you ask me... Any half decent tuner would tell you "do as your tuner did will end like your engine has"......

There is so much wrong information in this whole thread! Honestly 90% of you keyboard warriors have no idea what has really gone on so i find it astonishing your able to give your seemingly "expert" opinions on this topic which you dont know anything about, other than what has been stated. No one in this thread was with the car when it failed so how can anyone comment or badmouth the tuner? has anyone seen a motor detonate and cause this sort of damage running 13 degrees on full noise at 11.9 - 12.0 AFR ?? just curious.

You'll get a MUCH better result if you go there and ask nicely to see them. Don't assume they are at fault, it will only make things much harder for you.

Instead, go there with your objective thinking cap on and listen to what they say, take all the information on board and then ask some other experts about what has been said. Try to take someone with you who might know a lot more about these things.

Think about trying to find out WHY rather than WHO and the WHO will work itself out in the end.

no not the tuner. was at the workshop at the time. ^^^ this post is THE ONLY attitude to have when things like this happen, all this other crap doesnt achieve a thing and just pisses people off making the issue harder to resolve.

There is so much wrong information in this whole thread! Honestly 90% of you keyboard warriors have no idea what has really gone on so i find it astonishing your able to give your seemingly "expert" opinions on this topic which you dont know anything about, other than what has been stated. No one in this thread was with the car when it failed so how can anyone comment or badmouth the tuner? has anyone seen a motor detonate and cause this sort of damage running 13 degrees on full noise at 11.9 - 12.0 AFR ?? just curious.

What was the timing like on the ramp to boost, at peak torque and what were the afr's throughout the runs?

What was the timing like on the ramp to boost, at peak torque and what were the afr's throughout the runs?

As i said i was just an onlooker, was at the shop at the time, and heard the information i gave above spoken about after the motor started having issues. Like i said, anyone with half a brain knows this isnt the way to go about resolving such an issue.

10kays to bed engine in before making decent power??

10 - 15 mins is more than enough if done correctly.

Now i dont know the whole story but one thing is for certain ZERO chance of it being the intake design, if its smoking out the catch can and a borescope shows damage then it has either had incorrect ring end gap and they have butted when its got hot or piston to bore clearance was too tight. Injector issues also factor in.

BUT TBH the most common failure i see on new engines that are bought in for assessment are trigger offset angles in the ecu, many times the shop has set timing off the back timing loop instead of with a lead on number one cylinder this often makes the base timing way out (up to ten degrees) Ive had 2 haltechs in the last few months come from a particular tuner that had this done and irreversibly damaged big dollar engines. Another issue with rb's is a warped cas mount plate this can skew timing by around 15-20 degrees (had one as recent as yesterday).

First thing to check is correct base timing via cylinder one not the loop.

second thing is to pull it down and determine without doubt the cause. Once apart there is no way to sugar coat what has gone wrong... build ot tune... simple.

Till then its all speculation and is not going to help anyone.

There is so much wrong information in this whole thread! Honestly 90% of you keyboard warriors have no idea what has really gone on so i find it astonishing your able to give your seemingly "expert" opinions on this topic which you dont know anything about, other than what has been stated. No one in this thread was with the car when it failed so how can anyone comment or badmouth the tuner? has anyone seen a motor detonate and cause this sort of damage running 13 degrees on full noise at 11.9 - 12.0 AFR ?? just curious.

How do u know it was actually running 13degree's timing. And at wat boost?

Regardless of timing and afr if there is detonation damage it should have been heard by the dyno operator and the run stopped.

Tuner will blame engine builder, engine builder will blame tuner :)

How do u know it was actually running 13degree's timing. And at wat boost?

Regardless of timing and afr if there is detonation damage it should have been heard by the dyno operator and the run stopped.

Tuner will blame engine builder, engine builder will blame tuner :)

Thats why pulling down will answer all questions... without doubt.

Alright guys cheers very much for the input!

Just to be Clear, I'm not here to slander either the engine builder or the tuner, which is why I won't name them.

The cas disc is another thing the tuner mentioned he was going to have a look into.

Now, for pulling down this motor and finding what's failed, should that be on the workshop to remove the motor and have it pulled down by the builder? Or should that be my problem to pick up the car and do it all myself?

Cheers

Sorry anyone following this thread.

Is their a way I can have this thread deleted by a moderator?

I appreciate everyone's input, but for now I would really like to sort this issue out one on one with my tuner/builder.

When the out come is found il relay it back to here.

But for now I'd really like this entire thread deleted.

Cheers

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