Sydneykid

Hi Oosh, the amount of air trapped is tiny and the pressure is quite low by pneumatic standards, so not much of a hole is required. I wouldn't worry how small you go. Increasing the bleed hole size (by enough ot get 2 psi) is not going to improve the boost build much. You still get some pressure at the wastegate actuator, so it will open progressively.

A couple of things to note; 1. Since your log on is RB-26 I assume that means you have an RB26. They have top feed low impedance injectors. The most common style and much easier and cheaper to get than the RB25 side feed high impedance. You don't have to use a Jap "brand name", you can use Bosch, Nippon Denso, Jecs, Rochester etc etc 2. You can use a datalogit with or without the Commander. I use the Commander instead of buying many gauges. 3. The output of most wide band lambda sensors will plug straight into the Datalogit, they are usually 0-2 volts so nothing tricky to set up. On a street driven car we use Bosch sensors and run both a narrow band lambda sensor (for closed loop economy) and a wide band for tuning. 4. Commanders are specific, although the one you want is the most popular. This is the table from Meggala's web site http://www.meggala.com/powerfcmodel.html 5. If you are changing injectors and AFM's (and expecting the sort of horsepower you should get) then there is no way you can do the tuning yourself, unless you do it on a track. You would end up in jail tuning the top end, high load maps. My 20 cents worth:cheers:

Price comparison to buying a Jap "brand name" wet sump pump; The last pump I used on an RB was a 3 stage (we use 5 stage on V8s), cost ~$700 The tank was 7 litres, cost $400 We use aluminium pipe through the cabin, cost $150 The aluminium weld on fittings were $50 The short hoses were $200 I made the pump mounting bracket from some scrap aluminium say $20 We already had a drive pulley, they are ~$30 Total ~$1550 Obvioulsly if you are going to dry sump the engine it needs an oil cooler, but that would be the case with a Jap brand name pump upgrade, so no extra cost there. Ditto lines, filter and block adaptor. If you don't do the dry sump, then it needs a wet sump with wings, one way doors and baffles. That actually costs more than a dry sump pan, but is most likely offset with the cost of the fittings to plumb up the sump. It's a reasonable cost comparison, I know which I would choose. PS; If you need to do the full job (including oil filter, braided stainless lines, remote filter mount and block adaptor) then add around $900. Plus the sump conversion to dry sump, around $800. Total ~$3,200 plus fitting labour if you can't do it yourself.

Go Advanced Middle of the symbols, above the writing box is "Insert Image". Click on it and put a link to the image file there. You have to have the image hosted on a server of course Skylines Australia has a nice picture hosting site if you don't have another Hope that helps:cheers: PS; for Burns, I think the Gold Buddy Clubs would look much better on a blue Stagea. I will swap you for some brand new, opened box, 17 X 8 HollowType R's as seen on our race R32GTST. Silver, matching your car perfectly :aroused:

It's a 678 universal Hydra-Cool, I got it from my local Auto One. I didn't ask for Trade, I forgot and was in a hurry, no order book with me. If it had been $250, I would have gone home and got the order book.

Maximum possible fuel economy is usually achieved in closed loop (cruising) so I doubt that the max would improve much if at all. I have leaned ours off from 13 to 1 to 14.5 to 1 in low load (not closed loop) so there is a bit to be gained there. The main gain is in WOT running, I have leaned that out from 9's to a bit over 11's. So there is 20% to be had there. Plus the extra power means I don't have to squeeze the throttle as hard to get up to speed. So there is a bit there as well. By the time you offset that with the fun factor from 30% more power, you might end up with 10%. My best so far is 15% improvement, but the Stagea is very heavy, has 4wd losses and zero mechanical mods. I ma sure the exhaust upgrade will help a lot (both power and economy).

Spot on. This is a Peterson 5 stage dry sump system. So called because the pump has 5 stages, 4 scavenge and 1 pressure. It picks up oil from 4 places, three in the sump and one on the cam covers. It pumps the oil it picks up via a filter into the top of the tank. So there is very little oil in the sump itself, hence the term "dry sump". The pump is supplied oil from the bottom of the tank and pumps it under pressure via a filter and oil cooler into the engine. The advantages are; 1. The tank is tall and skinny, unlike a sump which is short and wide. So there is no chance of the oil moving away from the pump supply. No oil surge. 2. The oil comes out of the engine with air mixed in it, as it flows into the tank it runs over a strainer/ramp system that removes any air from it. This means the engine is only supplied pure oil, not aerated. 3. The tank is remote, so the oil is not heated by the engine while it waits to get used again. 4. You can have as much oil in the dry sump tank as you want. I have seen 25 litre oil tanks, you can't get that much oil in a sump. This means the oil does less work as there is more of it. so it lasts longer. 5. The oil is filtered twice 6. Any blowby is sucked up by the scanvenge stages, so no oil mist in the engine or anywhere else (like in the intercooler as happens with standard sytems). 7. There is no oil in the sump to get hit by the crankshaft as it spins. If you choose the sizes of the scavenge stages correctly and have good engine sealing you can achieve a partial vacuum in the sump. So not only is the crank not hitting oil as it spins, it is also not hitting air. There is a good horsepower advantage in doing this. 8. The dry sump tank can be mounter remotely (in the boot) so the weight distribution is improved. Ditto the breather and the filters. There are a few more, but that's the majors. Hope that helps:cheers:

OK I give up, I looked at the list and it says "manual tansmission cars only" when it doesn't fit an auto. The R33 RB25DET does not have "manual tansmission cars only" printed after it, so doesn't that mean if fits an auto? :headspin:

Gosh, I hope it rains soon, so some of the crap on this thread gets washed away. :wassup: :wassup: :wassup: :wassup:

Try doing a search on Walbro, you will be amazed what you find when you do a search. If you had done a search before posting this often asked question, you would have found lots of great info that would provide an answer. The search button is your friend, use it often. PS; Did I mention that you should do a search?

I am not to goig to pick on other people's designs, they may well be superior. What I will say is, the ones I use for circuit racing have wings both sides and they have one way doors out of those wings.

I am not sure I understand this thread at all, it doesn't make sense to me. Let me explain why.... The 4 boost settings on the PFC are exactly that 4 BOOST SETTINGS. If you want 1 bar then select 1 Bar, if you want 1.5 bar then select 1.5 bar. All this does is enable the ECU to tell the boost control solenoid when (how often) to close so as to limit the boost to that level. Nothing more, that's it. You tune the maps for the maximum airflow you want to run. Whether you get there at 1 bar or 3 bar is irrelevant. The AFM measured the airflow and the ecu tells the injectors how much fuel to squirt according to the maps you have loaded. Obviously a Power FC without a Boost Control Kit fitted still works fine, there is no boost table to set. On some cars the PFC doesn't even know the boost level (no map sensor). It simply doesn't need to, as long as it knows the airflow (via the afm) then it can do its job of matching fuel and air. That's one of the advantages of an AFM sensor driven ecu. Hope that clarifies:cheers:

The best example I can give is the 265 rwkw R34GTT which has a standard Nissan head gasket in it. My rule of thumb is, if it needs forged pistons then it needs the block o'ringed. Personally I never use Jap "brand name" head gaskets, they are rediculously overpriced for a start. How the hell can they justify charging $500+ for an RB26 head gasket and ~$250 for an RB20 head gasket? They are both the same size, in fact the RB20 head gasket has more material in it as the bore sizes are smaller. If you think you need to reduce the comression ratio, then relieve the combustion chamber volume, using a thick head gasket is technically an inferior solution. It stuffs up Nissan's good work on the squish zones for a start.

I posted this in another thread but it applies here; This is the ever popular Moroso SMC circuit race sump, note the wings, trap doors and baffles; This is the Morosa Ford circuit race sump, note the wings, trap doors and baffles; Now compare those to the Moroso SBC drag race sump, note how deep it is and it has no wings, trap doors or baffles The design is different because drag cars don't go around corners, so side to side centrifical forces do not have to be catered for. The drag sump is designed to stop the oil from being forced up and back under acceleration. For a proper race engine, we have some simple rules we follow; Rule #1 don't have an engine with excessive blowby, keep the tolerances accurate, use gapless rings, run the engine in properly. Rule #2 only allow as much oil as you need to flow up to the cylinder head. There are 2 oil feeds to the head in all RB's. GTR's have a restrictor in one feed to limit the oil flow. We block that one off completely, it simply isn't needed at constant high rpm's. Rule #3 clean out the oil returns, port them so they return more oil to the sump quicker. Rule #4 have an external oil return to the sump, into the top of the left hand wing is normal. Check the RHS wing on the SBC sump above. Rule #5 run a big catch can. with baffles and or stainless steel wool inside to separate the air from the oil. Rule #6 use a sump with baffles, trap doors and wings. Run a crank windage tray to make sure the crank doesn't whip the oil on rotation. And a crank scraper to remove as much oil that is following in the partial vacuum that the crank creates as it spins. Rule #7 try not to use Jap "brand name" oil pumps (the ones that fit in the standard location), a full dry sump kit is cheaper and far more effective. When using a dry sump set up have one of the scavenge stages picking up oil from the cam covers. You can't compare to the Gibson GTR's they had to run under the Group A rules, which didn't allow dry sumps if I remember rightly. They did use an external oil pump (same as a dry sump pump) but they returned the oil to the sump, not a remote tank. Hope that is of some help:cheers:

Never seen side feed injectors on an RB26:cheers:

The engine would stop if if I turned the power off to the DFA and it would go max boost (that the tubo can develop) with no power to the IEBC. I have asked JE and he reckons they used a DB25 switch to swap over when they were developing the prototypes. I have got one around here somewhere, so I will give it a go soon and post up the results.

That's the largest you should need.

For a proper race engine, we have some simple rules we follow; Rule #1 don't have an engine with excessive blowby, keep the tolerances accurate, use gapless rings, run the engine in properly. Rule #2 only allow as much oil as you need to flow up to the cylinder head. There are 2 oil feeds to the head in all RB's. GTR's have a restrictor in one feed to limit the oil flow. We block that one off completely, it simply isn't needed at constant high rpm's. Rule #3 clean out the oil returns, port them so they return more oil to the sump quicker. Rule #4 have an external oil return to the sump, into the top of the left hand wing is normal. Check the RHS wing on the SBC sump above. Rule #5 run a big catch can. with baffles and or stainless steel wool insde to separate the air from the oil. Rule #6 use a sump with baffles, trap doors and wings. Run a crank windage tray to make sure the crank doesn't whip the oil on rotation. And a crank scraper to remove as much oil that is following in the partial vacuum that the crank creates as it spins. Rule #7 try not to use Jap "brand name" oil pumps (the ones that fit in the standard location), a full dry sump kit is cheaper and far more effective. When using a dry sump set up have one of the scavenge stages picking up oil from the cam covers. You can't compare to the Gibson GTR's they had to run under the Group A rules, which didn't allow dry sumps if I remember rightly. They did use an external oil pump (same as a dry sump pump) but they returned the oil to the sump, not a remote tank. Hope that is of some help:cheers:

The remote filters are mounted high up, next to the fuse box because it is easier to get to them there. Good Jap mechanics charge like brain surgeons, so you probably save a $100 per oil change in labour. All remote and cooler installations are "sealed" otherwise the oil would squirt out under pressure. This means no air can get in, if no air can get in then the oil won't drain. It has to be replaced by something, otherwise you would have a vacuum created by the draining oil. Some links... This is the ever popular Moroso SMC circuit race sump, note the wings, trap doors and baffles; This is the Morosa Ford circuit race sump, note the wings, trap doors and baffles; Now compare those to the Moroso SBC drag race sump, note how deep it is and it has no wings, trap doors or baffles The design is different because drag cars don't go around corners, so side to side centrifical forces do not have to be catered for. The drag sump is designed to stop the oil from being forced up and back under acceleration. Hope that is of some help:cheers:

You might, best to wait and see what duty cycles you have to use on the IEBC to control the boost to your desired levels. Then make the hole the apropriate size. That is logical as the Stagea has lower boost levels which is the main reason why they develop less power when standard.

Nope that sounds right, but it is load sensitive on the Stagea. I didn't try it by just free reving the engine, so 4,500 rpm might be right under those conditions, On the Stagea it is certainly different in each gear, it doesn't open at all in first or second. This keeps the boost on the low limit. And when you hit the "Snow" button the solenoid also stays closed, regardless of the gear or rpm. Which sounds logical, I guess you don't want more power in the snow.

The Davies Craig trans cooler kit was $150 retail. I am not a fan of the "bent pipe with fins hanging off it" style. I prefer the "tube and fin" style, so the black one in the top left of your photo looks the go.

Standard ignition system and AFM's (a pair of RB20/25's will do fine).

We have Datalogit for RB20, RB25, RB26 and SR20. Good stuff, it adds lap top tuning and releases a few tables and maps that are hidden when using the Commander. Plus it logs data as well of course, we use a couple of extra channels from sources other than the Power FC (water pressure and oil pressure) www.fc-datalogit.com

Yeh, lucky, hey. It was coincidently the right size, most bypasses are 0.75 to 1.5 mm so not tooooooo much of a coincidence. Obviously it had to flow greater than 4 psi (the lowest std boost setting) otherwise Nissan would have needed to use a bigger hole to dampen the air flow. So I knew it would be more than 4 psi when using it as a bypass. I had a target of 0.5 bar but I would have been happy at 0.4 or 0.6 bar. It ended up right in the middle at 0.5, so no worries. Ahhhhhh yes, but it pulses open-shut-open-shut-open-shut.............. The frequency and duration of the pulses determine how much air it bypasses.