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As title says, why do so many people have rebuilds done on these engines? Are they not well built and reliable? Or are the people doing rebuilds the ones that have modded the car too heavily or driven the car with little respect on a track etc?

Surely a relatively stock rb26 if serviced regularly and looked after will last as a solid engine?? :)

Any opinions welcome

Edited by r32line
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As title says, why do so many people have rebuilds done on these engines? Are they not well built and reliable? Or are the people doing rebuilds the ones that have modded the car too heavily or driven the car with little respect on a track etc?

Surely a relatively stock rb26 if serviced regularly and looked after will last as a solid engine?? :)

Any opinions welcome

most engines making double the power they were built/designed for fail before too long.

Surely a relatively stock rb26 if serviced regularly and looked after will last as a solid engine?? :)

Well thats the thing.

Keep it stock-ish. Dont chase more than 240rwkw and it will last ages.

Chase more, stock turbos fail, killing motors.

Oil problems can arise if you arent overfilling.

But yeah, when your making double the factory power, something's gotta give and thats generally when they let go.

People go for too much power without the right parts.

I am looking at buying one that is very stock (only exhaust, and the boost restrictor has been removed - but its only running 12psi) and it made 197awkw... I don't plan on modding it any more because I will be happy with that as it is... so I was checking that if i look after it, it will be a reliable engine

"As title says, why do so many people have rebuilds done on these engines?"

Because they are put in a chassis where they can be punished and provide immense enjoyment when doing so :)

it sounds like youve got a grasp on what kills them, so you should be able to prevent it the best you can

This question does not have a simple one or two line answer as there are far too many variables to consider so the correct response is... "it depends".

Primarily I have found the major cause to be the mechanically unsympathetic nut behind the wheel. They choose to not understand their car needs maintenance and it needs the right support mods to make the power they want. They also choose to believe the odometer when it says 6X,XXX kays on a 10-18year old car despite the interior condition which usually tells no lies, so they think it's still fresh and can be flogged a bit. An engine has a finite life and will need a basic rebuild or three sometime through a long life. I just purchased an 03 XR8 ute with just under 100, 000km and it looks pretty good compared to the interiors of a host of imports I have seen with far less than that. Not that I think the Falcon has anywhere near the same build quality, I just realise that imports have the speedos wound back in almost every case.

They blow because they are:

1. not designed to make 14+psi on the stock turbos for too long, which can rupture and cause catastrophic engine damage,

2. even with the right turbos the injectors run out of capacity so detonation results and that cracks pistons and damages bearings, and

3. they are just plain tired and a number of events result in a failure.

Oil surge is extremely uncommon, but the appropriate mods can help overcome the issue. filling the sump the correct amount, running the motor to ensure oil capacity is correct and then topping off again Then overfilling with a litre of oil will work until you start to brake and corner extremely hard on semis or move to slicks.

Otherwise, buy the car, enjoy it and don't overdo it without providing the right attention and it will be great for a long time.

I always used enough oil to get the level near the bend in the stick (hope that makes sense)

I do the same, to keep her happy. Three years and still going strong. Put in the whole container of oil 5l and get it to bump on dipstick.

Oil and filter change every 3000km, plus oil cooler and filter relocator.

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