Cubes

Cheerz Big Earz.

I wouldn't bother with splitfires until yours die. or.. I guess you could sell your working coils and put the $$ towards a set of split fires so you KNOW they will not have problems in the future. Now thats got me thinking.

A little bad news. The RB20DET springs are the same as the RB25DE springs. The RB20DET springs are fine for the rb20det as the valves are smaller, throw the larger/heavier rb25de valves behind them and you run in to valve float anywhere from 11 to 17psi depending on a few variables. Its interesting you went the R33 RB25DE VCT (All R33 Rb25de's and DET's are VCT) inlet cam as the centerlines are way out for a non-vct setup. The R33 inlet cam runs the same duration and lift as the R32 Rb25DE and Rb20DET inlet cams, just different centerlines. The R32 Rb20DE inlet cam is a little pissy thing so definitely not worth even looking at that one. Definitely best to throw an adj. cam gear on the r33 inlet cam to sort out its centerline.

Which atmo inlet cam did u go? RB20 or rb25? The RB25 inlet cam is more agressive as its 240duration 7.8mm lift vs the rb20 n/a 232dur 7.3mm lift. Have you done valve springs? I am going to try and track down an rb20det exhaust cam and drop it in to mine when I do my springs in a couple of weeks after exams. The stock rb25de n/a exhaust cam is 232duration 7.3mm lift and doesn't really have optimal centerlines. The rb20det exhaust cam is ok but could do with a little tweaking via an adj. cam gear.

Awesome so it did the trick. Looks good, sits much lower in the engine bay than I expected.

I simply had the line entering the little box do a 180degree bend and connect to the rubber hose connector, this bypassed the little box and loopy line. Made it so much easier to bleed. Clutch feel, it appears instantly the clutch is much easier to regulate, its as if the pedal has a higher resolution when feeling that oh so fine ceramic puk take up point. Basically.. Made it nicer to drive, in 40degree peak hour traffic the clutch was fine, but I don't do track work so I can't tell if there's a problem with clutch fluid boiling.

Download and isntall microsofts resizer powertool here < Resizer 512kb > Then select the photo's you want while holding down shift right click your mouse button on any of the selected pictures and select resize pictures from the popup menu. Then use the newly created resized pictures to upload. It will default to 640x480 which is fine but 800x600 is nicer.

Also remember that 400hp at the treads won't be in first or second as a turbo sized to provide such airflow doesn't get going until third and fourth. You will find it is quite crap in first, second is ok then third rips. The only way to get around this is either supercharge OR displacement.

Here's a GCG Highflow bolted on an R34 GTT with cams @ 14psi. Appears to be up almost 20rwkw at ~100km/h

In the case of the RB20, r33 Rb25, r34 rb25 and vg30 turbo's I really think shaft speed is the very last thing to kill a turbo, I believe high egt's/detonation is the likely cause. Raise boost you raise airflow, actual outlet temp raises (especially if its running in to choke), backpressure within the turbine housing builds. Compounded you have one awesome receipt for detonation. So what do we do? Reduce ignition timing to prevent detonation and we raise EGT's. Are we better off running it a little richer so we can keep some decent timing in there? I would assume so however It would be awesome to have a play on the dyno with an egt guage to see the benifits of tuning in this manner. Why R34 GTT's running stock boost have been known to let go when you hit the track also supports the EGT theory. Another mention that 'may' support the EGT theory and not so much the shaft speed is: As you increase boost you dramatically increase shaft speed, improving VE also increases shaft speed but no where near as dramatically as higher boost levels. The R34 GTT turbo runs the larger VG30 OP6 style turbine housing, larger turbine housings reduce back pressure resulting in higher VE that results in lower boost required in order to flow x amount of air in and out of the engine. But do consider, as you make more power you make more exhaust gas, as a result backpressure 'may' be the same as the smaller housing just at a higher power level. The R34's do make more power stock and are generally known to make roughly 10rwkw more than the r33 rb25 turbo. I'm not completely sure on this maybe disco could share his thoughts. As all RB turbo's share the same turbine wheel (same size, trim everything); one can rule out the turbine wheel weight differential between the turbo's as to why one would let go before another. When setting up my bodgy actuator some time ago I accidently pushed 18psi through the stock turbo through second gear. IF it was the case that the wheel has growth surely that squirt through second gear would have been enough time to grow as a result collecting the turbine housing. So to conclude.... Turbine shaft speed is directly related to airflow not boost. Boost is definitely comparable on a given motor/turbo setup, not to be used when comparing different turbo's on different motors. i.e rb20 vs rb25. The question remains... Is it turbine shaft speed or high egt's that will get to the turbo's ceramic wheel before the other. I believe egt's.

Good thing I don't have an engineers degree then. lol I've always thought it comes down to 2 things that break the ceramic turbines. Excessive EGT's (i.e track use, been known to have a turbo let go at stock boost) Foreign particles (spark plug bits due to detonation or as you state carbon) High turbo's RPM, well yes, with excessive shaft speed the turbo will be spinning out of its efficiency, back pressure is high as are actual inlet temps. Both of which contribute to high egt's and detonation. I'm not sure the boost is really such a good example as its airflow that really matters. A good example of this is how an RB20DET has a ceramic turbo spinning at 1bar for years yet do the same with an RB25DET and its ceramic turbo will let go sooner rather than later. I believe thats basically what you have said Geoff.

Sounds like speculation to me.

Yes DaFuca, There's a sticky in the SA thread. http://www.skylinesaustralia.com/forums/in...howtopic=121767 Mention where your at and keep it in the family. Its always good to have a fellow enthuiast working or looking over another enthuiasts car.

I'm not so sure.. I really am of the view that if the car doesn't look stock.. well prepare to be harrased. All of my previous cars were aussy cars, all lowered, loud exhausts. The last car was a nice 3yr old VS 5ltr 5speed, Bilstein suspension, sherbrook green, nice exhaust and I was pulled over every second week. This car... Pulled over once in 4 years. EDIT: Make that 4.5yrs. Damn I've had this car a long time. OR if your on your P's or have a history of speeding etc. I base this on when I was younger, I used to be pulled over every so often on my P's, I was then done for something silly which was fairly serious and after that for the next couple of years I was ALWAYS pulled over just to see where I was going what I was doing and the usual car inspections.

Its very interesting you say that. I've known a few ppls that have worked at Bob Janes, yes they are young and yes they all flog the cars that come in. Always story's to tell..

And how does one bond the ceramic to the shaft.. This is where the problem lies, its not a ceramic shaft.

In short, Aim to keep those EGT's down. What raises EGT's one engineer may ask another? Reduced Timing Detonation Lean mixtures off topic.. Nizmoid.. Get your hand off it. hehe Thats disturbing.

Do you mean the muffler add to back pressure. That really depends on its build quality and design. A straight through muffler that holds the same pipe ID and doesn't protrude anything in to the airflow will be fine. With the removal of a cat convertor you only just notice an improvement in spool and top rpm power so a piece of pipe with a couple of holes in it that don't protrude in to the airflow won't be noticable. It is important to have a good muffler on the car, up around 300rwkw odd it can make or break it. Some of the jap mufflers tend to squeeze in running a smaller id pipe inside the muffler, this is obviously bad bad bad, but is fairly quiet.

Added back pressure isn't too good for turbo spool or preventing detonation.

Providing the bottom end is in good nick save a little, don't rebuild it *just yet* and drop the comp (8.5:1) with a thicker headgasket if your aiming for over 250rwkw. + all the usual supporting mods. Injectors Fuel pump PFC + PFC EBC (pfc ebc's are relatively cheap) Exhaust FMIC Clutch Cams and be sure you have a good tuner. You may also have to upgrade the diff or shim the std item, throw pineapples in the cradle to stiffen it up a little, suspension, brakes and wider/better tyres. It all adds up very quickly. as Mr. Nizmoid stated, 15k from STOCK is about right.

Here's one of the only pics I could find of my old buggered injectors. I have close to 5000photo's so it takes so damn long to find what I want if I haven't made the effort to sort when downloading from the camera. But as you can see the top is a clear type top with a tinge of yellowish.

The problem with those is you can't really give it a boot full and keep it quiet. Nothing better than a nice quiet car to give it a bootfull and not attract attention.

My 92 GTST had white/clear/yellowish injectors that had a red dot on them. Injectors in the R32's are the clear type like I had or Red. I suspect mine were tinged yellow due to heat. The RB20DET injectors are the same as the R32 RB25DE injectors, both 260cc. I used to get pretty damn good fuel economy and still do even with the 3ltr. My o2 sensor used to work spot on, I replaced it when all of a sudden I was getting ~350km's to a tank. The new o2 sensor made bugger all difference so I replaced injectors with new flowed items and instantly back to the awesome fuel economy its always returned. Check the usual o2 sensor and ensure its working well. I've got a pic of my old injectors laying around.. give me 2 secs to get them up.

Well yer as I said.. In the US you have to do a small course in order to report incidents as such. I believe it too was called neighbourhood traffic Watch.

AVCR is a good option. Have it setup on the dyno so it doesn't spike and carry on. The AVCR has a few nice features like different boost levels for rpm or gear. Another good option is the Blitz SBC-id. Both of these ebc's learn the boost curve and adjust duty cycle to ensure you achieve the boost target both at low and high rpm. The Jaycar item is good if you have the confidence to put one together.