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Iv found a daily driven car that's also used on track running a bigger version 0.73ar as mind are 0.64 or 0.61 can't remember that's running hks 272 with 10.5mm lift with springs retainers and seats. And ported head. Although its making 720hp..

Full boost around 6000rpm sounds about right, which means you'll need to change each gear at over 8000rpm to keep on boost.

I'd stick with mild cams ~270° max, with moderate lift. High lift and duration cams are harder on the valve train. The large turbos will extend the top end significantly anyway. Just focus on getting a lighter and stronger reciprocating mass. Get some strong and light pistons, rods, nice bearings and get the crank checked. Probably look at a dry sump setup.

Can't see a stock RB26 holding onto those revs at high boost for long, especially on a track.

As per the above post, given the fact that your power band will be moved up between 6,000 and 8,000+ rpm.

I am running 272 deg cams at 10.5 mm lift and these are probably not enough to support such high rpm operation. Their efficiency range is much lower rpm, probably coming on at between 3 and 4000 rpm, which is suited to my longer-stroke, slower revving 3.1 and smaller turbos. Yes going bigger with cams means more doughy down bottom - it will be slower off boost than a VL commodore - but for that size turbo you are optimising for high RPM operation. I think the above suggestion about 280 deg would be the minimum, as you will need big duration to maintain 'acceptable' ramp angles.

And your mum probably won't be impressed if you throw her the keys to drive it down to the shops, as per your thread about the turbos, but that's a given for this setup.

Decided to ditch these and start on building a new engine.

Your engine is more than likely capable of high 300s if you choose the appropriate turbo. Shouldn't need to rebuild it, what turbo are you thinking of replacing it with?

At the moment looking into building a stroker engine. I know the obvious for streetability and response the choice for turbo are twin bolt ons and they will punch out the numbers i want but as iv said somewhere iv always wanted a single turbo 26. I thought people are getting decent results from mid sized singles these days?

At the moment looking into building a stroker engine. I know the obvious for streetability and response the choice for turbo are twin bolt ons and they will punch out the numbers i want but as iv said somewhere iv always wanted a single turbo 26. I thought people are getting decent results from mid sized singles these days?

My personal preference is for a single, tricky to match or better a good twin setup but definately possible.

That said is it your 2835's on ebay atm?... i think i need them, whether or not i win them is another story :P

Na they aren't yet mate. They'll be up soon tho. Do you want me to let you know when they are?

i'll keep an eye out, set my ebay snipe for the pair on there now so we will see how it goes.

With the stroker my brother who's a mechanic is gonna help do all the non critical rb26 stuff. He isn't in a performance scene but is full of knowledge when it comes to all mechanical stuff. And has put me onto an engineering shop in addl who's build some of adel hardest gtr's

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