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I've searched everwhere for this info on the site. For some reason can't find it but I'm sure it exists.

Can someone please tell me what the safe limit of power and torque at all 4 wheels is for a standard RB26 with good support systems and a good tune?

Car is a street driver, no track work so will see max power rarely.

Thanks

Can someone please tell me what the safe limit of power and torque at all 4 wheels is for a standard RB26 with good support systems and a good tune?  

When you say STANDARD what do you mean? Standard exhaust? Standard boost? Standard fuel? Standard ECU? Standard injectors?

SK has issues with the word STANDARD:D

No, not really. This isn't the same problem as the other thread...

If the GTR has standard 414cc injectors then that would mean the limit is 414 bhp

If it has larger injectors then it's the fuel pump, so that's 425 bhp

If it has standard exhaust, then it probably won't get to the limit of the injectors.

If it is running standard boost, then it definitely won't get to the limit of the injectors.

One mans STANDARD is another man's HIGHLY MODIFIED. :headspin:

Ok well ill add to this... how much power roughly would shot peened rods hold? Basically ive been told thats the weakest link in my engine rebuild, although im only after 300 - 350kw at all wheels.

i belive a rb26 with standard internals can hold 320-350rwkw, if its just a daily driver and not track driven, then i think it should handle 350rwkw without touching internals...

this is what i've been told - not from experience

Ok well ill add to this... how much power roughly would shot peened rods hold? Basically ive been told thats the weakest link in my engine rebuild, although im only after 300 - 350kw at all wheels.

Nope, I reckon it's rod bolts.

Nope, I reckon it's rod bolts.

Sorry forgot to mention its got ARP bolts :Oops:

Basically engine has been rebuilt, standard crankshaft polished and balanced, shot peened rods with arp 2000 bolts, arias .5mm overbore forged pistons... not after a monster, more so a fast track car... it has Tomei sump baffles, but am looking at swapping this for Trust extended sump and baffles (intend to do a bit of track work with it) which brings me to my next question... is it overly difficult to change sumps with the engine still in the car? :)

Guest two.06l
Sorry forgot to mention its got ARP bolts  :Oops:  

Basically engine has been rebuilt, standard crankshaft polished and balanced, shot peened rods with arp 2000 bolts, arias .5mm overbore forged pistons... not after a monster, more so a fast track car... it has Tomei sump baffles, but am looking at swapping this for Trust extended sump and baffles (intend to do a bit of track work with it) which brings me to my next question... is it overly difficult to change sumps with the engine still in the car? :)

we have seen 390awkw with very similar bottom end had no dramas ..yet.....

I've seen 410awkw from an R34 GTR with standard internals.

Who knows how long it would have lasted though (it was detuned and converted into a daily driver a few months later)...

I'm sure we could screw 450awkw out of a stock RB26, but for how long?

The more power you make, the shorter your engine life will be.

Guys;

the key phrases are;

stock RB26 and good support systems .

So...assuming that FMIC, bigger inj, turbos, PFC, boost (pump fuel) and the rest of the whole enchilada in terms of support systems including a good tune is present, but the engine retains stock internals, what would you recommend as a safe maximum AW power and torque figure ie one that will allow a stock engine to enjoy a long and happy life, bearing in mind that it isn't going to get hammered regularly because it's a daily driver and I don't want to go to jail.

Hope that makes sense.

Thanks

My idea of "support systems" maybe different to yours, mine would include;

*cams

*valve springs

*adj pulleys

*porting and combustion chamber work (in lieu of a thick head gasket)

*oil cooler

*winged, trap doored and baffled sump

*clutch with lighter flywheel

*oil pump upgrade

*oil return from head to sump

*ball bearing water cooled turbos (in lieu of plain bearing oil cooled turbos)

With your list, plus the above, I see no reason why ~310 awkw would not be achievable for a daily driven car that sees the odd circuit or strip. :D

My idea of "support systems" maybe different to yours, mine would include;

*cams

*valve springs

*adj pulleys

*porting and combustion chamber work (in lieu of a thick head gasket)

*oil cooler

*winged, trap doored and baffled sump

*clutch with lighter flywheel

*oil pump upgrade

*oil return from head to sump

*ball bearing water cooled turbos (in lieu of plain bearing oil cooled turbos)

With your list, plus the above, I see no reason why ~310 awkw would not be achievable for a daily driven car that sees the odd circuit or strip. :D

And presumably at that level you'd expect it to last for some time?

cams are Poncams so I'm not intending to change valve springs

don't intend head work because I don't want to remove the head

sump, pump and oil return not planned as it's not going on the track

turbos are R34 N1s

got exhaust, Z32 AFM, PFC/boost kit, HKS Type R IC, adj pulleys etc

sound OK? tell me if you think my assumptions are 'out' or there's a flaw in the plan.

Ahh, the ever beautiful R34 N1's, I reckon you you can let 'em rip. Make the most boost you can out of them and watch the inlet air temp. You will see when they top over on efficiency. The inlet air temps skyrocket rapidly, usually around 1.4 to 1.6 bar depending on intercooler efficiency, ambient temperature etc. Keep it under that and you will live a long and prosperous life, as long as the rest of the tuning is up to scratch of course.

Word of warning, it is not always changing cams that mean you have to change valve springs. If you exceed the limit of the spring rate, the inlet valves will stay open because of boost pressure. The result is neither pretty nor cheap to fix.

Hope that helps

PS, I would like to see the dyno graphs when it is done.

Sorry forgot to mention its got ARP bolts  :Oops:  

which brings me to my next question... is it overly difficult to change sumps with the engine still in the car? :D

Is it possible to install sump baffles / change sump without removing the engine???

the ever beautiful R34 N1's.  

Now...you're scaring me.  

exceed the limit of the spring rate, the inlet valves will stay open because of boost pressure.   The result is neither pretty nor cheap to fix.  

I bet. You'd  suggest replacing them at N1 friendly boost levels then?  

I would like to see the dyno graphs when it is done.

Happy to do so.  

the ever beautiful R34 N1's.

Now...you're scaring me.

exceed the limit of the spring rate, the inlet valves will stay open because of boost pressure. The result is neither pretty nor cheap to fix.

You'd suggest replacing them at N1 friendly boost levels then? Do you have a recommendation?

I would like to see the dyno graphs when it is done.

No problem.

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