whats the aux belt fix then JohnS, and why's it not advertised on any of the specialists sites (not that I've checked recently, maybe they are now???).

how much does it cost? Or is it only avail on the £5k+ engines?

At least if you bought something at 400bhp standard (say a 6 litre Monaro VXR) lets say you carried out a supercharger conversion on that, you'd have an entirely reliable, 3 yr manufacturer warranty 500bhp RWD car, instead of an unrealiable FWD 500bhp?

S1MMA all above examples are harsh but fair. You know I like Supras but a good friend of mine who has a tuned supra blew both turbos when a 'engineer' overused the NOS. The point is that if you go past certain manufacturers tolerances and things break - don't be suprised.

Difference between a 500bhp coupe and a 500bhp Monaro is about £20 K in resale value.

If I cared I would have sold my coupe 6 years ago when it was still worth something

At least if you bought something at 400bhp standard (say a 6 litre Monaro VXR) lets say you carried out a supercharger conversion on that, you'd have an entirely reliable, 3 yr manufacturer warranty 500bhp RWD car, instead of an unrealiable FWD 500bhp?

With the M5 in there I;m not sure given the VANOS failure rate and ongoing clutch issues And the former is more expensive to fix than a shiny new 2.4 engine fitted excluding ancillaries.

As for the Monaro, for the mileage I have done in my coupe the engine would have paid for itself in saved fuel costs probably, but that aside I agree that would be more reliable on average as it is a very well proven engine which dates back almost 50 years and uses technology 3 generations or more before the likes of constantly variable camshafts and the like.

And other than that yes I would agree in general but not for the reasons you think - the reason is the approach taken to the tuning.
The thing is there is no reference to your comparison with the 2.4s because everyone with a 2.4 except Taz have very aggressive ignition maps that takes nearly all of the safety margin out which is the most likely place where a small displacement high power car will go wrong, whereas you can get quite a lot more out of both cars you mention through more ignition which is why you can still 'chip' them.

Aux belt has nothing to do with the power IMHO, and whatever the cause the problem it has been solved. I don't buy that it is anything to do with power as std cars have also failed.


Let me ask you a question then...

The std 220BHP fiat coupe engine has rods that have tolerances that are +/-10g compared to each other (and are literally a different shape from one rod to another) and pistons +/-5g compared to each other. That creates massive offset throwing forces that are the equivalent to those in an engine with probably twice as much power at 7000rpm with a tenth of the tolerance.

Now take the rods out and put 30% lighter rods that are 4x as high power rating with rod bolts that have 4x as much strength and are all 0.5g of each other. Take the pistons out and put in pistons that are 20% lighter, the ring lands are good for 5x more power and the rest of the piston 4x more power, the gudgeon pin 3x more power and are also within 0.5g of each other. The piston can also take more det if it is exposed to it.
Take the sodium filled exhaust valves that are good for 1200C and put in exhaust valves that are good for 1600C.
The pistons, rods and valves come from the very best manufacturers who built their brands on reputation and reliability, improved strength and fatigue resistence

Adding these to a 220BHP coupe does it make the engine less reliable?

Why is it less reliable at 500BHP when it is still further inside its tolerances than when it was as standard?
The other key parts in the engine are the crank (which is forged anyway), the balancer shaft, the oil pump, dare I say it belts, head gasket, water pump and all the head (springs, cams, valve seats etc). None of these are commonly known to fail at any power level, nor are they particularly exposed to more power aside from the crank. So why is this 500BHP engine now so much less reliable?

The reason why high power tuned cars are less reliable are that they are beyond the component tolerances, the ancillaries are not up to the job, they have taken all the safety out the ignition and maybe also a lack of respect for the extra heat generated. Maybe the reason is doing half a job in a lot of cases.

Spelling aside i will be going to live in new zealand before the years out and the holden monaro is the family car over there.
Anyone got any info on the supercharger kit for these beauties...