R33 Rb30 Conversion

[Cubes]

Godzilla,

There's not a lot of room for tensioner movement before it fouls the lower cam cover. Do let us know how the 149tooth belt goes with the 2 tensioners.

[Roy]

Just sticking my head back in here to see if anyone running the R32 RB25DE head hac recently changed their inlet manifold to the Plazmaman etc inlets and noticed a difference

[Cubes]

I'd like to know how that bloke went who was running his plazman on the rb25det runners.

Scooby? or someone I think? I can't remember.

[Scooby]

not me

[Craved]

  Cubes said:

I'd like to know how that bloke went who was running his plazman on the rb25det runners.

Scooby? or someone I think? I can't remember.

Guilt Toy is running the plazma man on his rb30, and i will too. unfortunatly the change cant be measured as we both already have it installed.

[r33_racer]

well shit...uninstall it and do a power run...then reinstall it...god take one for the team ya slackers

[Cubes]

Either way if it makes its peak power up over 6000rpm and holds power well then we know the plazman is working well.

Am-Performance's has a stock exh. manifold, HAD a stock plenum and that nosed over after 5500rpm.

Bolt the plenum on and it just wants to keep making power over 7000rpm and most importantly holding power. Just his valve springs are currently letting the package down.

If it still noses over with the plazman then we know the inlet runners are the killer, do note that Ripz that has been playing with RB30dets since the dawn of time throws short runner gtr style plenums on all of his 30det's.

[Craved]

  r33_racer said:

well shit...uninstall it and do a power run...then reinstall it...god take one for the team ya slackers

HAHAHHAHA

i dont think so

  Cubes said:

Either way if it makes its peak power up over 6000rpm and holds power well then we know the plazman is working well.

Am-Performance's has a stock exh. manifold, HAD a stock plenum and that nosed over after 5500rpm.

Bolt the plenum on and it just wants to keep making power over 7000rpm and most importantly holding power. Just his valve springs are currently letting the package down.

If it still noses over with the plazman then we know the inlet runners are the killer, do note that Ripz that has been playing with RB30dets since the dawn of time throws short runner gtr style plenums on all of his 30det's.

yeah i have seen the RIPs plenums, we will see.. only 1 thing left before i build the engine and that is to take apart a spare rb25 oil pump and make sure its all in good condition, then i'll bolt it together and see how we go.

guess we'll have to wait and see..

[SirRacer]

sydneykid was building rb30's before RIPS and says the inlet poses no restriction. in the thread you posted up re the plenum the results were not considerable enough to put it down to that as being a restriction.

[Cubes]

  SirRacer said:

sydneykid was building rb30's before RIPS and says the inlet poses no restriction. in the thread you posted up re the plenum the results were not considerable enough to put it down to that as being a restriction.

When did SydneyKid say it poses no restriction/isnt the case of power nosing over early in that thread?

Have another read of the thread. Nothing of the like was said.

Sydneykid said (refering to the dyno sheet attached) one is better off with a motor that doesn't rev where you shift up early as the motor will be more reliable and it will accelerate quicker (more low mid torque) so a peaky power curve rather than a wide power curve.

HOWEVER... With a GT35r this is not the case as the power band is too narrow, SK then went on to say well its poorly setup and shouldn't be run. etc etc.. Which is true.

A GT35r .82 on an Rb30DET with the stock plenum is a bad setup. They need a plenum simple as that.

Run a GT30 and I believe with the stock plenum its a near perfect match.

I have seen it with my own eyes. It is what causes the rb30det's to nose over early.

The attached dyno sheet was the back to back run at 8psi, no ebc, 2.5" exhaust.

The before power run was tuned nicely. The after power run only had its afr's tidied up as 800cc twin sprays were dropped in. NO ignition was touched. So its quite possible there were gains to be had.

Do what you will... Myself and my tuner knows what prevents the rb30det's making power up close to 7000rpm. If the car that makes its peak power at 5500rpm is faster than the one that makes its peak power at 7000rpm is irrelevant.

So choose what sort of motor you want. A turbo diesel or a higher reving typical sports car motor.

The comparison dyno sheet attached is of:

RED: An rb30det setup (gt35r .82), stock plenum, stock exh manifold, Tomei 260duration 9mm cams, an EBC, 3" exhaust, 19psi ON AVGAS.

Blue: the 8psi setup, no ebc, stock cams, aftermarket plenum, afr's tidied up, no ign tweaking ON PULP.

Green: 17psi, no ebc but a bleeder, stock cams, aftermarket plenum and a little valve float. 1bar made 265rwkw, 2psi more (17psi) made another 5rwkw due to valve float. PULP.

Do what you will with those results. There's more of others with aftermarket exh. manifolds and stock plenums still nosing over but I don't have the dyno sheets.

My bets are throw AVGAS in to the blue/green rb30det, ditch the 2.5" and drop on a 3", the set of 260duration 9mm cams and boost will come on just as early BUT still hold to a higher rpm.

[SirRacer]

ill keep you posted for comparisons sake in a few months

im doing gt3540 .82 housing with q45 power fc and an aftermarket manifold. will add another dimension to the results

[cordiapower]

I have a problem for rb30 experts: I put rebuilt rb30/25 in my r33. I found out just after 1500km that car was stalling whenever the clutch pedal is pressed and was loosing oil pressure and short after oil pressure lamp was turning on and after some checks oil pressure to the head was zero. The engine was pulled apart and we found out that central thrust bearing in the middle of crankshaft has grinded one sidewall and snapped that side off completely blocking oil flow...what could cause this? Bear in mind that car has all new parts weisco forged pistons, rb30 rods, race bearings and done only 1500km?

thanks

[r33_racer]

The bearings werent in arse about were they?

[cordiapower]

  cordiapower said:

I have a problem for rb30 experts: I put rebuilt rb30/25 in my r33. I found out just after 1500km that car was stalling whenever the clutch pedal is pressed and was loosing oil pressure and short after oil pressure lamp was turning on and after some checks oil pressure to the head was zero. The engine was pulled apart and we found out that central thrust bearing in the middle of crankshaft has grinded one sidewall and snapped that side off completely blocking oil flow...what could cause this? Bear in mind that car has all new parts weisco forged pistons, rb30 rods, race bearings and done only 1500km?

thanks

If it matters its got Extreme heavy duty 9 pack ceramic brass button 2500lb pressure plate clutch

[cordiapower]

  r33_racer said:

The bearings werent in arse about were they?

they were i assume because of no oil flow?

[r33_racer]

How did it last 1500km then?

[cordiapower]

no oil flow happened after 1500km and its due to snapped central bearing (one side of it snapped) in the middle of crankshaft, im wondering why did it happen after only 1500km and how could it snap in such a short time?

  r33_racer said:

How did it last 1500km then?

Edited January 23, 2007 by cordiapower

[r33_racer]

perhaps a faulty bearing?

[Craved]

  r33_racer said:

perhaps a faulty bearing?

further on that, perhaps the crank was machined too far for the bearing? meaning that thecrank was able to shift forward or back, which cracked it ...

similar to the clearance a big end bearing requires, im sure that the thrust bearings have them too.

[Scooby]

maybe check the end float on the crank. if there was too much end float or the crank was able to move back and forth along its axis for some other reason it would do so when the clutch was manipulated. if the crank moves far enough it will shift the bearings and there goes your oil pressure.

IF the clutch and stalling are really related rather than seeming to be that way, it could be that when the clutch is depressed it moves the clutch and flywheel - and crank if there's enough float - so far that the side loading on the pistons creates enough friction to stall the car at idle.

this suggestion could be really wide of the mark but it's the best one i can think of.