rob82

Pump flow rate goes up with less pressure - hence if you remove the pressure you get more flow rate. I have used this fuel system on XR6T's running E85 up 450rwkw.

You can also run an 044 in parallel in stead of inline with the intank pump this way they share the pressure so your flow rate is equal to an 044 at half the rail pressure.

3in 100 cell will flow upto 250-280rwkw 3.5in 100 cell will flow upto 300-330rwkw 4in 100 cell will flow 360-400rwkw 5in 100 cell will flow around 500rwkw if you double the cell count you knock off about 25% of the previous figures. Most 100 and even 200 cell cats won't meet euro4 emmissions. For that you need at least 400cell. Hence why c63 amg have twin 7in cats to make the poer they do and still meet emmissions.

The way a desired AFR map "should" work is to enrich the mixtures. ie 12:1 is an enrichment of around 22% over stoich. I haven't used the haltech software as I just dont like using them but if its anything like an autronic then changing the desired AFR map will result in a change of fuelling.

Thats the whole premise behind lean cruise strategies they had in the late 90's. As your lean the mixture you need more throttle hence the pumping losses are reduced as the vacuum reduces as well. The other thing most people dont realise is that the highest EGT's are around stoich ie 14.4-15 either side of this AFR the combustion chamber temps go down. Advancing the timing 5-10degrees will help also. I would also look increasing your plug gap if you can. Also if you are tuning VE and your VE is correct then I would just change your desired AFR table to say 17:1. That is if the haltch software works properly.

With a KKR440 you will loose about 15 - 20rwkw thoughout the entire rev range until aboyt 7000rpm where it will make the same power as the std manifold maybe a smidge more. You will also loose about 500rpm spool rate. I'll see if I can find the dyno graph. Runner length is heavily dependant upon rpm not mass air flow. Hence even if you have a turbo that can make huge airflow down low its unlikely that a short runner will make more hp than a long runner, until the topend anyway.

You will loose runner length with the rb26 manifold. This means you will loose horsepower throughout the entire rev range until about 7500rpm where it may make more power if the valvetrain and turbo are up to the job.

How were your motors built? Was the reduction in combustion chamber volume bias more toward pisotn design or cylinder head design? What size cams were you using at that compression ratio? What was the cranking compression? What timing numbers were you running on 20psi on pump? What was the propensity to knock like? Did you use the factory CAS or were you using a crank trigger? I think these are the type of question you need answered.

You only really need it if you want a cold idle up - or to stabalise idle with AC or power steering request. It obviously depends upon your ecu tho. That manifold is a waste of time on an RB20 in allmost all applications.

The neo is the pick of the heads IMO - you've got narrow valve angles, smallcombustion chamber, vct, mechanical heads. Can't see why it wouldn't go on the rb26 - just need to do the same mods as the rb30/25.

The biggest problem with th RB26's is the massive chamber volume meaning you need to run massive domes on the pistons to get any sort of compression increase which then puts more stress on the rings. If response is your biggest motivator I would be aiming for around 9:1 comp and look at getting VCAM if the budget will stretch.

No way the base timing on the CAS has moved?

Thats post is a little ambiguous - first he assumes there is a problem with the combustion chamber design incorporating the quech pads and then he goes onto say that he's torched two motors due to bad CAS/ECU. The bad CAS/ECU are a known problem on all skylines and I too have had issues with high rpm ignition scatter. But I've never believed there is any issue with the quench pads/sqiush bands. I can tell you that removing quench pads on high comp 4valve motorcylce heads will only cause more detonation. And from what I've seen you could correlate the results of bucket actuator 4valve motorcyle heads to that of the RB series 4valves heads. If I were you I wouldn't be concerned about running the factory head gasket even up to 25psi if you have head studs. I would stay away from dropping the comp with a thincker head gasket as you are reducing the squish - which wont help at all! Is there a reson your concerned about what has been done to the head thus far? Is there an issue with detonation or the engine not liking timing?

That cranking compression is fine for a fairly well std RB25. Alot of the evo's are around 175-195psi with a static of 8.8:1. Cranking compression has more variables than just static compression ratio.

Good luck finding lift at TDC specs on these thing nobody seems to keep these specs. The factory manuals have valve opening and closing times. Time to get the cam degree wheel out. Your lucky with the NEO as there is no hydraulic lifters so just throw a dial gauge straight on top of the bucket and away you go.

The load axis is theoretical pulsewidth (based on maf voltage and injector constant) not throttle position. Don't let the knock feature of the factory system sway your judgement when selecting an ecu as it's quiet poor and will usually only revert to the lower octane map if you see lots of knock at low rpm high load. That being said I'm a big fan of the factory system compared to most other aftermarket ecus.

When you screw them all the way in they dont allow any boost source to pass through - typical shit turbosmart design. If you want minimal boost screw it all the way in and then back 2-3 clicks.

If you can retard the timing 8degrees from MBT (Minimum best timing) and not loose any torque you have built a non dynamic engine. This maybe due to low compression pistons combined with larger duartion camshafts. The other problem with thicker head gaskets is that you reduce the squish clearance which has a huge effect on timing sensitivity. You should be able to put a bit more boost into the engine to give you more cylinder fill but anything more than about 25psi with that turbo on an RB25 is pushing you outside the efficiency of that turbine. I would try that first and if the engine is still unsensitive with ignition timing changes then I would be putting a thinner head gasket in to raise your static and dynamic compression.

It's more the retarded ignition event that will help spool the turbo. Unless it's that rich and retard that the combustion event is occuring in the exh - that's what we call anti lag.

If the gate has insufficient diameter to bypass the exh wheel then you will get boost creep. Have you tryed wiring the gate open and seeing if it still creeps. I've seen alot of aftermarket wastegates that crack at there preset level say 10psi but aren't fully open until around 30psi. Have you tested your wastgate movement vs input pressure.

If there is no signs of it burning oil then it's either a leak or a turbo seal.

Do the plugs show any signs that it's burning oil?

You are correct but generally the bigger the injector the worse the atomisation which has an effect on power as well. Plus the times you need good atomisation, eg- idle and light throttle the duty cycles are that low that the injection phase angle has a huge time frame in order for the tuner to determine the optimal injector angle. BTW if they are the ID1000cc EV14 injectors they will tune and delivery better fuel economy than the factory injectors.

Screw the old chargers get the new TVS chargers - they are much more efficient. http://www.eaton.com/EatonCom/ProductsServ...s/TVS/index.htm The R1900 would be my pick for around 300rwkw @ around 6psi of boost at 6700rpm on a 3.5L.

Not 100% its been a while since I've scoped a skyline. I'm sure the specs on the LSx coils are correct tho as well as the dwell times. I would definately check the triggering type before installing the coils tho.