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If you wanted to make max HP with near to 10,000 RPM's what combination of Nissan RB components or heavier duty substitutes would you use for reliability??

May sound crazy but we want to use a hybrid RB in a dedicated 800Kg pure drag car that relies on RPM more than torque to make enough power to crack nines.

The trans is a fully modded Nissan manualised transbraked auto with a 5000RPM stall converter.

Any suggestions....?

You may actually endevour to make us see the error of our ways if you actually know what you are on about. :argue:

Rather then hunt for 10,000rpm, why not just chase a certain power figure? The valvegear that will allow those sorts of revs is going to be very expensive.

RB26 would have to be best place to start, but the valve gear etc will still need to be updated. What sort of power do you need in a rail to run 9s?

that RPM is going to be much harder and MUCH more expensive to achieve because of the valvetrain costs (titanium valves etc are not cheap) than, say, 800rwhp in an RB26/30. keep the standard valves or just get larger ones, forged rods and pistons in the 3 litre and it will get there no worries. run a huge turbo (or 2) because lag isn't a problem and set the rev limit to 7500.

Rather then hunt for 10,000rpm, why not just chase a certain power figure?  The valvegear that will allow those sorts of revs is going to be very expensive.  

RB26 would have to be best place to start, but the valve gear etc will still need to be updated. What sort of power do you need in a rail to run 9s?

Hi Roy, if Turbine & I (RB Racing) make 450/500 RWHP we will do tens as previous owner did with a Hemi 6 Chrysler. We want to do it with around 2 litres.

I guess I did not explain very well but I was looking outside the square on this one like for instance ....

An rb30 with RB20 crank & rods... ??

Interesting most responses were on the valves being able to handle the revs but no one mentioned crank/rods/pistons and more importantly piston speeds.

We are starting with a totally stock RB20 with a ATP custom Turbo with a custom wastegate from an aircraft, as well as custom Air to Liquid intercooler and 3mm TRUST Metal Head Gasket on cleaned up NA head.

Autronic will manage the spark and fuel with custom intake and 12 standard RB20 Injectors and VL Turbo Pump.

More on this setup here

RB20 Dragcar here RB20_fitted_2_small.jpg

although probably not one to ask i'd start witha 26 cause it'd flow more (sounds like your gonna try and do it on the cheap side) and bust some billit crank rods in it 70 mm stroke crank, definatly some aftermarket valves stainless is still good enough, 3mm gasket damn thats phat whats wrong with getting the right pistons and porting the chamber (what fuel you ganna use?) and on the fuel side that pump and injecters sounds to small ( but depends on power and fuel used)

if you want something out side the square dump the turbo and go full nitrous rb 20 DE

Shame you already have an RB in there. A 1GGTE would have been a nice option. Few mods on them get them really moving. In a drag application you could really push a stock bottom end.

Good luck with it tho. Post results and that. Will be interesting to see how the little RB goes! :D

sorry mate - thought you were talking SERIOUS power :(

as for the RB30 with 20 crank, i am pretty sure it doesn't work, but don't quote me! just go and grab one from somewhere and see if it physically fits first.

personally i would turn it into a 25/30 hybrid - it will make the power you want quite easily.

if you absolutely MUST stick with the 2 litre bottom end, don't mess around with it. do as much work as you possibly can to the head (massive porting, larger valves, massive cams etc) and you might make the power easier than you think. for the 2litre, i'd be looking at a GT42 or similar, with lots of NOS to get it on song. water/air cooler with dry ice for the run and a fair whack of pre-turbo N20 and i suspect it will make that power.

forged rods and pistons are a must. the crank *might* be okay, all i can offer here is that the RB30 crank is good for up to about 800hp but mostly because of its low rev limit.

Kinda odd, unless you are trying to fit into a capacity restriced class (under 2 liter?) or get a certain weigh break (afaik ANDRA Sport Compact are cylinder dependant weights).

Either an RB30 or RB20 is going to cost the same amount of money, you're going to have more money in the induction than bottom end anyway so what's $200 for a nicely used VL taxi motor? :(

RB20 crank in an RB30 block will net 2.3 liters? As well as requiring custom rods + pischtons. Probably going to find with an RB20 head the ports are way way way too small and the valves as well due to the RB20 having a smaller bore. A standard RB26 head will flow more.

Add in the hydraulic lifters on the RB20 head, and the weaker springs in the NA and you've got a great challenge getting this thing to make any sort of power. The solid lifter conversion is more than a set of double valve springs for an RB26, no doubt you'll want to run the doubles if you are pulling 10K rpm.

But hey, at least you don't have VVT to worry about with it :D

Edit: and the manifold? Long tuned runners for low down torque?

Thanks Guy's! ;-) Some good feedback.

More Info= Sorry should have done this earlier.

We have 2 stock RB20DE's to burn -originally spares for my GTS4 - but not needed now.

We also have a RB30NA block and RB25 NA head for further down the track when we exhaust the potential of the RB20 and see how far we go before it lets go!

But for now we are happy to spend as little as possible to get it on the track for the first time as soon as possible as we just purchased it from a guy in QLD that run it with a Hemi.

After all it is a Chrysler Valiant!! We have owned many of this model in coupes and Glenns old 318 pulled 12's with nitrous -been there done that. We also are building a AMC '69 Javelin 401cu V8 TowCar with a GMC Supercharger and Fuel Injection for those that MAY suggest a V8;-)

No, we want to stretch the RB20 and eventually run the RB30/25DOHC when we get used to going reasonably fast with the little RB20.

The Autronic will keep the tune OK hopefully so we wont destroy it with detonation and give us a chance to see how far the mechanicals can go under loads of boost.

WE WANT TO BREAK IT!! But not too quickly!

Our aim is to sit on the start line and take it to max revs and boost and drop the trans brake or is that BREAK;-) The sliks will NOT spin or slip - Check them out!

The 9' diff wont break either and hopefully the Auto trans will hold together with over $3000 spent on the Jatco 3 speed, 5500RPM stall converter and Transbrake setup.

We dont need no stink'n long torque tuned manifold runners ;-)

Well, apart from the head not having the biggest valves or ports for that matter, the RB20 could be the right engine. Considering its stroke, at big revs its always goign to have lower piston speeds, which is a good thing. Also the fct that it has smaller bore means the piston will be lighter so less reciprocating mass, another plus for big revs.

The bottom end uses bearing sof similar size to the bigger RBs so again when you look at the piston speeds and rotating mass then the bearings shouls have an easier life at big revs with the little RB20.

But here comes the thing, i priced up a Tomei solid lift kit with 270 / 10.25mm cams a few months ago and it works out to be $2500. If this gear could be thrown into an RB25DE heac then it may make more sense...but to have to throw it away when you decide to go RB25/30 etc is a waste of money, byut there is a good chance it can be used with the RB25De head.

So with a bit of port work the cams with big lift and solid conversion, some 81mm pistons (if it still has to be 2.0L then std diam pistons), stress relieve the std rods with good studs, a crank collar and better oil pump...on paper there is no reason at all why the monster RB20 wouldnt make 500rwhp if you threw a GT3540 on it with a hit of say 1.5 bar of boost.

Well thats what id be thinking and hoping anyway...god id love to do it and rock up to the drags and pull a good time

ive personally seen 10000rpm in a RB20 .. with cyro treated rods and crank forgies and a GT3540 turbo on board ...... was making 241rwkw at 12psi or something .. cant remember .. was Glenn Hunters GTSX coupe .... did have a Rb26 previous and was featured in Zoom .. but it smashed the water pump at 11500rpm at a drift nats in sydney. so the rb20 went in to replace it.

Things to be careful of:

Water/Oil cavitation from spinning at those revs - reduce their speed

Camshaft lift being too big will mean a valvetrain made of million dollar unobtanium

Rotating assembly will need to be very very very well balanced

Adrian

How bout you try an rb20 with a 2.4 stroker kit in them? The rev to 10-12k depending on cams and springs, and your laughing. We have that setup with two turbs.. seems ok? makes 400hp, might seem low for you guys, but for a gtst drifter.. is very good.

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