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Dont push that stock engine to far!


JamieP

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Can someone explain what blue printing is then please.

 

i have not read it but just what wiki says

 

Blueprinting

In engine blueprinting, all the specifications are double-checked. Usually this indicates closer-than-factory tolerances, with custom specifications appropriate for a street car or a race car. The goals are either to re-manufacture the engine to the rated power for its manufacturer's design (because not all mass-production engines put out the rated power), or rebuild the engine to make more power from a given design than otherwise intended (because custom engines can often be redesigned to different specifications). Blueprinted components allow for a more exact balancing of reciprocating parts and rotating assemblies so that less power is lost through excessive engine vibrations and other mechanical inefficiencies.

 

Ideally, blueprinting is performed on components removed from the production line before normal balancing and finishing. If finished components are blueprinted, there is the risk that the further removal of material will weaken the component. However, lightening components is generally an advantage in itself provided balance and adequate strength are both maintained, and more precise machining will in general strengthen a part by removing stress points, so in many cases performance tuners are able to work with finished components.

 

For example, an engine manufacturer may list a piston ring end-gap specification of 0.003 to 0.005 inches for general use in a consumer automobile application. For an endurance racing engine which runs hot, a "blueprinted" specification of 0.0045 to 0.0050 may be desired. For a drag-racing engine which runs only in short bursts, a tighter 0.0035 to 0.0040 inch tolerance may be used instead. Thus "blueprint" can mean tighter or looser clearances, depending on the goal

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Sorry forgot that bit. Personally I would not run the stock block beyond the stock limit or 600bhp, to do so is living on borrowed time.

 

I did once read that 600 bhp was the original design criteria , probably at pretty stock rpms ,not hightened ones , but with modifications to stock in balance with what Toyota originally did then higher power is possible .

more servicing would be a given ,and closer measurement of certain limits ....oddly 2 guages that no one ever fits

1 detonantion indicator

2 cylinder head temp guage

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I showed the photo and this thread to a friend of mine who is extremely well qualified to hazard a guess at what has happened to that rod. He, and I would agree, but wanted reassurance, reckons 90% the engine suffered a misfire on that cylinder and at WOT the injector started to fill the cylinder with excess fuel and it hydrauliced. Probably a low coil energy or plug heat range issue, or a sticking (mechanically or electrically held open) injector.

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Air is easily compressed , fluids are not , so fluids can be used to transmit work , thus hydraulics are used to say move a digger bucket , the fluid pressure is used to move a piston in the hydraulic ram ..

If you screw a bolt into a blind hole , there is air in the hole it compresses ,now fill with fluid and repeat , the fluid wont compress ,so something eventually has to give the pressure builds so much eventually the thread strips...

in this case the piston tried to compress a fluid , the pressure rose to a point the rod bent!! known as a hydraulic lock

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i have not read it but just what wiki says

 

Blueprinting

In engine blueprinting, all the specifications are double-checked. Usually this indicates closer-than-factory tolerances, with custom specifications appropriate for a street car or a race car. The goals are either to re-manufacture the engine to the rated power for its manufacturer's design (because not all mass-production engines put out the rated power), or rebuild the engine to make more power from a given design than otherwise intended (because custom engines can often be redesigned to different specifications). Blueprinted components allow for a more exact balancing of reciprocating parts and rotating assemblies so that less power is lost through excessive engine vibrations and other mechanical inefficiencies.

 

Ideally, blueprinting is performed on components removed from the production line before normal balancing and finishing. If finished components are blueprinted, there is the risk that the further removal of material will weaken the component. However, lightening components is generally an advantage in itself provided balance and adequate strength are both maintained, and more precise machining will in general strengthen a part by removing stress points, so in many cases performance tuners are able to work with finished components.

 

For example, an engine manufacturer may list a piston ring end-gap specification of 0.003 to 0.005 inches for general use in a consumer automobile application. For an endurance racing engine which runs hot, a "blueprinted" specification of 0.0045 to 0.0050 may be desired. For a drag-racing engine which runs only in short bursts, a tighter 0.0035 to 0.0040 inch tolerance may be used instead. Thus "blueprint" can mean tighter or looser clearances, depending on the goal

 

Just for the record I am sure Jurgen just plucked figures out of the air as an example, but if you build your engine with a 3 to 5 thou inch ring gap it's going to seize as soon as it gets hot! Top and second ring gaps are usually over 15 thou inch!

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Air is easily compressed , fluids are not , so fluids can be used to transmit work , thus hydraulics are used to say move a digger bucket , the fluid pressure is used to move a piston in the hydraulic ram ..

If you screw a bolt into a blind hole , there is air in the hole it compresses ,now fill with fluid and repeat , the fluid wont compress ,so something eventually has to give the pressure builds so much eventually the thread strips...

in this case the piston tried to compress a fluid , the pressure rose to a point the rod bent!! known as a hydraulic lock

 

One of various reasons why you shouldn't drive quickl,y through flood water ;)

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I guess there are 2 options as prevention ,

1 fit an ECU with misfire detection , probably ££££

2 fit and or use brand new coilpacks,clips, and regular plug changes/checks - (I m going with the brisk plugs )

 

Option 2 seems prudent given known missfire problems with the supra engine on high boost , dont know if the DLI units do what they say they do ?

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I also killed my engine on the Top Speed run at TOTB 2008. A Dropped Plug caused the damage to mine damaging the Piston, 2 Valves and scoring the Cylinder bore. I will never run Denso Iridums again. Was running a fresh set of IK27'S when the tip of one decided to self destruct.

 

I had this a few times too Kev, used to run just a basic plug cost about £1.78 and change em every 500 miles, never lost a tip and used to run 2.5 bar no problem.

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Thanks Jurgen much appreciated mate.

 

Just remember that after its blueprinted it will need rebalancing, also to 'blueprint' an engine you would need exactly that, the blueprints for the engine as toyota designed it, so you could make sure all of your mass produced parts are the weight size etc Toyota intended them to be, sometimes you will end up buying many parts etc to get the 'perfect set'. For example I have had conrods vary wildly in weight engine to engine and then wildly end to end weight wise, for that reason when I keep conrods they are always kept in the same 'batch'. There is loads you can do to the engines, a nice de-burr and paint up with a specialist paint on the engine walls under the cylinders is pretty cool, I will do that to my new engine. You really notice weight difference when you go with aftermarket pistons and rods etc, even the rings are thinner, my supplier of rings for performance pistons can't even supply stock replacement file to fit piston rings as they are too thick.

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