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I saw it on the weekend, seems to drive alrite for whats a pretty BS engine. Id spend my money differently, but hey, good on him for giving something different a go and getting the power.

Just out of interest tho, whats the torque like on that motor?

  • 3 weeks later...
RB20 POWAH!!!!!!!!!!!!

2471Resize_of_Picture_045.jpg

Well, just to tell the next insatallment of the tale:)

Car is back together, and engine is running fine, albeit well down on power. Since the tune which gave me 222rwkws i had always run at least 1bar, when possible 1.3bar. So running std wastegate spring/boost pressure revealed that the only reason the car made the power it did was because of boost.

Ignition is pretty conservative, ie almost no existant:( ....I suppose you only have to look at the position of the CAS to realise this:(

So with no AVCR and about 8psi (late at night i managed to wind about 11psi into it a attacked Calder. At a guess the engine only had 150-160rwkws. The first few sessions i went pretty conservative with i think was a 6,800rev limit.

In the 3rd session as i was well down on straight line speed, and getting a little more c0cky i grabbed the hand controller whislt going down the straight trying to keep up with Ant95GTR and bumped up ithe rev limit. It helped bump my top speed up 18km/h...but meant reving it out to 8,000rpm in each gear and using 2nd gear where i would normally use 3rd on corner exits:(

So whilst power was down on usual, the rev limit and how hard i pushed the engine was higher then usual, with water temps getting as high as 107deg C

I have also changed back to Mobil 1, and im off to get another tuner to have a look at the Pfc and see if he can see why the ignition is so conservative. Hopefully an 8cm housing im chasing for my turbo will come my way, and ill be back with 220-240rwkws for a trip to Phillip Island in mid March.

The instruction to the tuner will be to tune the car to make the power the turbo is capable of. Dont worry about the power being too much for the std bottom end, spining a bearing etc etc. Just make sure there is good control of fuel and as much ignition as the engine can handle minus a few degrees. I suspect the last tuner wound back the ignition so that the engine made the power he felt the engine could reliably handle.

So ill put my hand up as the giunea pig to see if some of my thinking re-RB20 strength is true, or just misguided dribble:)

One thing that did surprise me was the water temp, Vic tracks seem to have londer periods of wide open throttle with foot to the floor acceleration. Places like Calder, Sandown, Phillip Island etc. NSW tracks seem to be alot more stop and go with varying speeds and part throttle. Perhaps this is the reason why i have noticed water temps abotu 10degress higher then normal. One thing is before Phillip Island ill try and suss out a nice thick aluminium radiator and big thermo fans, may even get a Nismo thermostat that cracks at about 14degrees lower then std.

If im leaning on the old RB20 i want to be sure that im at least keeping water and oil temps under as much control as i am A/F:)

..and because im pretty happy/proud of the job i did with the engione bay...im going to whore this photo around for the next few days:)

462After_Engine_Pic.jpg

What is the actual factory rev limit set at on RB20s?

I ask as mine has come back from tuning with a/m ecu and it made its max power figure at 6,000rpm as most do with factory cams.

The tuner set up the ecus shift light at 6,500rpm with the rev limiter at 7,000rpm. But it seems like the limiter might need to go up to maybe 7500rpm as it "feels" like its got plenty left in it and im short changing myself ( no pun intended ) shifting below 7000rpm.

What is the actual factory rev limit set at on RB20s?

I ask as mine has come back from tuning with a/m ecu and it made its max power figure at 6,000rpm as most do with factory cams.

The tuner set up the ecus shift light at 6,500rpm with the rev limiter at 7,000rpm. But it seems like the limiter might need to go up to maybe 7500rpm as it "feels" like its got plenty left in it and im short changing myself ( no pun intended ) shifting below 7000rpm.

7500rpm is the fuel cut.

lookin good there Troy :( Glad to see....

 

Is shaun goin to do your next tune?

Im going to get it tuned by a place in melbourne that is pretty involved in Vic Super Sprints etc, so hopefully he has a good feel for what an engine needs for track work when the oil/water/air temps start to climb.

Ill drop in to Shauns once Chris has his tune sorted to see how the setups compare...it looks like i have just scored an 8cm housign so i think the turbo will be almost as responsive as a 2530:)

As for the rev limit, yeh i find that on the dyno chart my power falls off after 6,200rpm, but by using those extra few revs up around 7,800rpm then after a gear change my engine always has between 180-220rwkws. LOL that is when its running the proper boost, the other night it would have been more like between 140-160rwkws:(

drop me a pm with your email, i already have a spreadsheet with the numbers for the R32 - RB20 gearbox...are R31 ratios the same?

Whats the theory behind retarded ignition making the engien run hotter:confused: ...i have never paid too much attention to what ppl recommend in the way of max water temps as mine have never been this high...what is generally the recommended limit? At $120 for the Nismo thermostat its cheap enough, but money that could be put towards a $600 aluminium radiator and soem Davis Craig thermo fans?!?!?!?!?!?!

Good to see mate,

back at work now. Shaun pretty busy due to the 4,6 and rotor nats, so car won't be tuned until then. Mine is down a bit of power atm, suspect I have a dodgy fuel pump as it was starting to get a bit of detonation

Good to see its all working again, are you still in town?

Whats the theory behind retarded ignition making the engien run hotter:confused:

Hi Roy, my understanding is the retarded igntion timing causes the combustion to be still taking place when the exhaust valve opens. This means that it continues to burn as it passes through the exhaust port. There is a lot of water cooling (jacket) around the exhaust port, so this excessive heat is passed into the water. Hence higher water temps. :D

PS; that car you saw at Philip Island, pole position and 4 race wins over the weekend.

Will be interesting to see the results of the 2835. B-man couldnt break the 300rwkw mark with one on a built RB25 with inlet plenum, cams etc etc and as much boost he coudl throw at it...so if you get the numbers out of an RB20 then you have done well:)

LOL...pole position and 4 race wins. Sounds like a good weekend:thumbsup: Please dont tell me it was at Mallala, i was thinking about going down to have a look as the Vic State Champs was running...and im working in Adelaide at the moment (Yeh Chris still in town..:rofl:)

Sorry for being off topic ppls.

Roy,

I've recently played with thermostat's in my sisters VL commodore.

Sure its a N/A stocker but giving it full throttle up willunga hill definitely gets things hot.

I had a new aftermarket thermostat (from Repco) and a almost new genuine Nissan thermostat.

I was curious as to how the two reacted to the good ol' boiling water in a jug trick.

The aftermarket even though it was rated at the same temp as the genuine would open slightly earlier and quicker. It also opened a hell of a lot more.

Roughly double the amount.

Obviously the genuine opened later and only opened slightly. Almost making me think was it stuffed or not as compared to the aftermarket it looked like the water flow would be severely reduced.

In the car the aftermarket took longer to warm the car up to operating temp (2nd line on the guage).

General driving with the a/c on caused the temp guage to fluctuate from the 2nd line to half depending on load. Turning the a/c off dropped temps to the 2nd line.

Heading up willunga hill at full throttle with the a/c on had the car creeping up over half temp.

Once off the throttle temps would come down again, turning off the a/c didn't appear to lower temps at all.

The genuine appeard to hold temps much much more consistant.

The car warmed up so much quicker and the guage wouldn't even budge with the a/c on.

Heading up willunga hill with the a/c on the guage only moved a needle width above the 2nd line. Only so you could just see the white line appearing from under the needle.

I then flicked back to the aftermarket 'just' to make sure and sure enough high temps under load.

My theory from a little discussion with some of the VLT blokes is that the higher flowing thermostat doesn't allow the water to flow slow enough through the radiator for the heat to transfer.

Maybe a higherflowing thermostat should really be tied up to a larger radiator in the VL's case.

I have had an aftermarket thermostat in the RB20DET and did find the temp guage to fluctuate a little. It ran slightly cooler but would creep up to its normal (Genuine) operating temp. Unsure how it would have gone on the track if the higher flowing thermostat would indeed cause the temps to keep rising and rising.

rb20det, hks t04e kit with hks manifold and 48mm gate. tomei cams, gtr cooler, z32 afm, gtr injectors, gtr fuel pump, remapped stock ecu pulled 224rwhp @10psi (nop boost controller)

Hoping for 350hp when boosted and apparently it shouldnt be very hard :rofl:

its in a ceffy too, laggy as doesnt spool till 4

  • 2 weeks later...

I don't own this car, but a guy i know pete does. He had a R32 with a standard RB20 in it running a GT35R turbo. With stock internals and just some bolt on stuff with compter fuel pump etc it made 319.3 rwkw (428.1hp) on 22psi at 7800rpm. It made that power at the Brisbane autosalon last year. With his built Rb20 with forged pistons etc, it made 358rwkw on 30psi at 8100rpm. It was laggy but hey it was a fun ride when she came on boost. Had run a 12.1 @115mph, but it wasn't running properly and was breaking down high in the rev range.

Unfortunately this car was written off in an accident about 3 weeks ago, but you can all read about it in the latest Fast Fours, as it is a feature car.

I don't own this car, but a guy i know pete does. He had a R32 with a standard RB20 in it running a GT35R turbo. With stock internals and just some bolt on stuff with compter fuel pump etc it made 319.3 rwkw (428.1hp) on 22psi at 7800rpm. It made that power at the Brisbane autosalon last year. With his built Rb20 with forged pistons etc, it made 358rwkw on 30psi at 8100rpm. It was laggy but hey it was a fun ride when she came on boost. Had run a 12.1 @115mph, but it wasn't running properly and was breaking down high in the rev range.

Unfortunately this car was written off in an accident about 3 weeks ago, but you can all read about it in the latest Fast Fours, as it is a feature car.

You sure it was a standard RB20 last year??? Not trying to have a go, but I was pretty sure that car has had a built motor in it for years.

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