StockyMcStock

would that be using a Q45 AFM as i am? that brief blurt of sound on full boost is the gate opening - in 2nd gear it gets from 80-120km/h in what feels like much less than one second.

i don't know actually - how do you do a map trace and get the controller to leave the peak values there? i can only get it to give me instantaneous readings at the moment. is there a trick? p.s. you need new codecs p.p.s. it's an XVID codec apparently p.p.p.s. go here and download it

you could be right there - i'm just going off what that page says down the bottom. either way, that style exhaust housing is what i have, not the V-band one that you posted. i'd love to have a look at the ID tag but it's a bit hidden on the car. here's a quick video of what it does in 2nd gear, then third for a little bit. ignore the tacho jumping around, there's a loose wire somewhere that i haven't fixed yet. Also starring: my feet! In a cameo appearance. edit: it's a 50mm gate - gets to 10-11psi or so at the moment. doesn't knock even on the standard RB25DET base map which is very nice. however, the injectors reach max duty cycle at about 5500rpm or so. i guess it's making a bit over 200rwkw then?

okay so the wierdest shit just happened. i can't explain a lot of it, but here we go: went out to the car this morning, same as last night. no lights on the controller, no relays clicking at all. so i check the power inputs everywhere. that's funny - the constant 12V line isn't getting power. so i trace the whole thing back into the engine bay - lucky i knew exactly where it all went because i wired it up. turns out one of the terminals right up near the battery on the fusible link had corroded just enough to kill my power at 12.30 this morning in the middle of the city. so i re-supplied it, no worries! oh shit, still no power on the hand controller. turns out the IGN fuse had blown. threw another one in. still nothing. so i bridged the fuel pump relay wires, but it wasn't going. however, when i bridged them, the hand controller turned ON. WHAT THE HELL? now it has power, but the fuel pump isn't going. there is a fault somewhere in the line. so i laboriously made a whole new wiring section from the battery in the boot to the 044, using a new relay and thick guage wire etc. magically, the car turned over and purred like a kitten. a kitten of spite. thank god it wasn't the PFC, i don't have enough cash for a decent gearbox AND a new computer.

Well i'm pretty sure my powerFC has taken something up the ass. I was driving along last night, not even giving it stick and the engine just died. pulled over, the hand controller isn't lighting up and it's not switching any of the relays (Eccs, fuel pump etc) that it normally does. All of the wiring to it is intact, and none of the fuses have blown. So is it possible to take it somewhere to get fixed/diagnosed etc? i'm reasonably handy with electronics but when it comes to testing chip outputs and memcals etc i'm out of my league. i'm going to see if i can test it by putting it in someone else's car (skyline R33 - any takers in brisbane?) but i have a feeling something is wrong with it. ECCS line was fused to 7.5 amps btw, everything else was factory VL body fusing. there are no burnt solder tracks on the PFC board. any ideas? cheers, Stocky

disco: that's my compressor stage alright, but the exhaust stage is different. i'm sure it's an 88mm 1.34 A/R on the hotside. here is a link to the exact turbo: http://www.atpturbo.com/Merchant2/merchant...tegory_Code=BCS it does use a T4 footprint on the hotside too, yeah. i boosted it in third yesterday once, right before the clutch started slipping. if you give it a bit of time to spool by using a higher gear, you can get quite good results out of it actually. i had 6psi by 4000rpm, then the clutch started slipping. the car is quite slow until you get to about 5psi, and then it all just suddenly hits you in the ass. 2nd gear is just scary. third feels just as fast as 2nd i guess my awesome manifold is spooling that big sucker up quick? that's the only thing i can think of this turbo would be a good option with the smallest A/R it comes in on the exhaust side i reckon, if you were using it on its own.

yep there's HEAPS of them, lots of trim variations that's for sure. it's a GT40 bush bearing. oil cooled only. 1.34 A/R exhaust stage - 88mm wheel i think? the compressor is an 82mm with a 0.72 A/R. the compressor stage has such a large A/R because i needed it to produce 500hp worth of airflow at a measly 7psi. the exhaust A/R is so large because the next step up, a GT42, didn't have the right compressor options that i needed to make it all work without surging. matching everything up was a bit of a bitch - given that the turbo is only providing about half the total boost pressure you need huge flow rates but low pressure on both turbine and compressor stages - an interesting thing to pick from a bunch of flow maps that's for sure. also went for a 50mm wastegate and i'm still hoping that it will be big enough.

if it's a GT3040 with a .82 rear then you will struggle to get to 300rwkw i believe. it will need large amounts of boost to do it if it does get there (>20psi i would suggest)

lol yeah i did notice that - it hasn't melted......... YET. i'm going to try and get some decent fittings brazed onto there some time soon. but so far it's doing okay? oh yeah, for you guys doing this on a budget, the above engine was built entirely by me. the car never EVER saw the inside of a workshop. i built the bottom end myself, the head got redone at a shop before putting it together. the plenum is a custom job of course, but i did ALL the piping and made the exhaust manifold. i wired it up myself and installed everything myself too. the engine revs beatifully out to 6,500 and just wants to go further and further but i'm not game. i might see if i can take a few vids of the boost guage and tacho this saturday night - it's hilarious how laggy it is. the car is about 3 times as fast in 2nd gear as it is in 1st because it doesn't make boost in 1st really! it doesn't wheelspin either because you're doing 80km/h before it really starts moving. 3rd gear is just scary - you'd need to be doing 120km/h before the turbo kicks in. overall, i love this engine so far. can't wait to get the M90 on there :eek:

no. not for long anyway.

haha yeah i'll take one. i ran over my AFM today (long story, stupid cooler piping clamps!) but got a new one tonight so i need a bit of new piping. should have it going again by the weekend i reckon. i'll see if i can take some in-car vids of it at the moment. it's hilarious to drive, you could boil an egg in the time it takes to hit boost, but when it gets to 5psi you better hold on! whackiest turbo setup ever. hint: there will be two boost guages when it's finished mmmm twin boost sources

correct, ze blower is not on yet. running a GT40 with a 1.34 rear housing only at the moment. very laggy, but immense top-end power. yep made it myself - the surface coating is peeling from the heat already it looks funky because i have to fit a supercharger in front of it.

guys i thought i'd post up some pics for you of my new engine setup. have it running on the standard RB25DET base map now, and it runs a treat! boosts well, is great off-boost as well. after a 100km run-in, i put the foot down a few times today on some nice straight stretches of road. to me, it feels like it's making over 200rwkw on 10psi. dyno figures to come later, when it gets tuned.

i would say it's not an issue to Tee the line in if you have quite a large oil drain from your turbo. for instance, mine is 3/4 inch ID braided line which is huge, even for an oil-only turbo drain. i would have no qualms teeing mine in, if it comes to that.

i would only suggest running that oil drain on your 30DET if you have re-routed the VCT line so you can use it. the VCT oil feed (via the front cam bearing face trench) is quite a large one, much larger than the other cam bearing oil feed holes. in addition to this, it does not matter if the VCT is ON or OFF, all that oil still gets dumped back into the head somehow, so you're ALWAYS getting a fair bit more oil in there. thinking about it logically, any RB25 head that doesn't run VCT from the factory didn't have that extra drain. so if you've disabled your VCT, don't worry too much about the extra drain.

i can't speak for a skyline engine bay, but in my VL i still have power steering and could run A/C in the factory location if i felt the need. removing or lowering the power steering pump down the block would give a bit more room if i needed it. as far as wastegates go, i'd generally get the smallest one you can, so that your control diaphragm to poppet valve area ratio is the highest it can be. a 32mm turbonetics or something would be good i suspect.

i've got an Eaton M90, same as used on the supercharged 3.8 commonwhores here in aus. mine came from the US though, and is newer. there were a whole bunch of revisions to the design over the years, mine is one of the more recent models. you're pretty much right there. i would expect it to feel a lot like a twin turbo big block V8, with very well sized turbos. stonking low-end pull, then it just takes off when the turbo comes on song. tony and i went to a lot of trouble picking the exact turbine to use, and i hope to see turbo boost well below 2500rpm. time will tell how good our estimates were though. god, i starting making the manifold today. what an abortion of a thing! you won't believe the lengths i had to go to with header routing to make it all fit.......

the supercharging is just a mechanical air pump. it takes in a fixed gulp of air, then pushes it out the other side of the casing. do it fast enough, and you get a pressure increase across the thing. now if you push more air into it by increasing the pressure at the inlet, it just passes that amount of air out the other side, same as before. except there's more of it. same as if you ran it at 50,000 feet above sea level where the air is less dense, it'd push less air out the other side. all you're doing is pushing more air into the same gulp that the blower takes. read my post again, you even quoted my explanation of why you should re-circ the vent back into the turbo inlets rather than the turbo-blower connecting pipe.

good thread! turbo bags + manifold wrapping seem a good way to go. people debate the longevity of steam pipe manifolds with thermal wrap, but i personally have never had a problem with my wrapping. i had a set of extractors wrapped for near on 2 years, removing the wrap two days ago and they were perfectly fine underneath. however, extractors don't get as hot as turbocharger manifolds.

if you re-circulate the bypass back into the supercharger-turbo connecting pipe, when you change gears at full noise you'll get massive air flow through the pipe, at high pressures, which relieves the pressure on the blower nicely. however, all this air then hits the turbo compressor wheels, in much the same fashion as in a conventional turbo setup. tony had it like this, and couldn't hear them surging, but technically it would be better to air vent it or re-circulate it back into the turbo INLETS. your picture is correct, that is how mine is set up, and tony's was too, except we just use a single large turbo. sorry i don't have any pics of it, it's not fully complete yet. i'm currently re-fabricating my manifold to a low-mount so that the blower can physically fit in the engine bay. there are a lot of packaging problems, trust me!

sorry i wasn't being hostile, just wondering if you realised that twin turbos was going to basically be an impossibility, with packaging. the bypass outlet can either air-vent (it's very loud though) or re-circulate. you could recirculate it back to the turbo-blower connecting pipe but you might get some huge compressor surge, and it would slow the turbine shaft speed down pretty sharply on gearchanges in much the same fashion as a normal turbo setup does with large pipework volumes. the other option is to vent it back into the turbo INLET, which is fine and should quieten it all down a fair bit. i had my SC-14 blower air vented, it was pushing fairly low air volumes but was extremely loud on gear changes! depends on how much you care about noise i guess.

the blower does draw power, just in a different fashion to the way turbos do. we're not saying that it doesn't, cause it sure does! it will draw more power than usual too, as it's working harder than if it were drawing in merely atmospheric pressure air. i'm not sure what you're getting at with the downshifting thing, just think of the bypass as releasing pressure from the piping when it's not needed. i'm not going to draw you a picture. turbo pulls in air, pushes this into the blower INLET. the blower OUTLET then feeds through your intercooler, with the bypass gate situated somewhere along the line here. then it goes into the engine. why are you set on using two turbos? wank factor? there is honestly no point at all to it. a single large turbo will be easier to package and work just as well. i would point out that it may be almost impossible to package two turbos and a supercharger into a skyline engine bay, especially if you have a power steering pump and an air con compressor.

nice spiel, but everything still comes back to compromise. turbochargers and superchargers are both compromises in some manner, it all depends on what you want from your engine, and how you want it to behave. well i'll show you how to do it, then you can give it a try seriously, it's hard but not impossible, and after seeing tony's results with the little 1.6L laser engine, i couldn't help but give it a try with an RB30DE. for me, the cost of an Opcon blower was too high, so i went with the twincharge. i may sell it all and try the blower out later on, but for now i want to see just how far i can push an eaton M90 with a GT40 together. packaging is the fun part...... ynhrgt: RE: that pic of the 26 up there. it's either a photoshop, missing parts or just a silly show demo thing. if you can figure out why it wouldn't work, then you are well on your way to understanding the twincharge system.

here we go, i found it. it relates back to the SC-14 blower that i was using at the time but describes the bypass system pretty well: "the bypass system is used to vent air around the blower (thus unloading it completely) at idle and light throttle openings. you will need an external turbo wastegate (i use a 32mm garrett item, but the bigger the better!) and whoever does your piping will make a flange/pipe attachment to the piping somewhere before the throttle body. the premise behind it is that a wastegate has 2 fittings, on either side of a diaphragm which "see" different pressures and thus act on the diaphragm. the diaphragm (and hence poppet valve which normally opens at a certain boost level and vents exhaust gasses) has a fitting above and below it, on the "cold" and "hot" sides of the wastegate respectively. the cold side is connected to your plenum (i use the brake booster line) and "sees" the pressure changes AFTER the throttle body. the hot side is connected to the intake piping after the blower, but before the throttle body. thus, it only ever sees atmospheric or above (boost) pressure. the idea is that the gate sees the pressure drop across the throttle body. now at idle, plenum vacuum sucks hard against the diaphragm and pulls the poppet valve open. this allows air to freely circulate out the open gate, the blower runs cooler and draws almost no power from the engine. when you close the throttle fully, plenum pressure = intake pressure, and the only thing acting at the wastegate is the internal spring, which holds the poppet valve closed hard. thus, you get full upstream boost. at any throttle openings between these two, the gate progressively closes and is fully proportional to your throttle opening. if you get your spring rate (stiffness) just right then you can cruise around all day without ever seeing upstream boost, but as soon as you put that foot down it's all there. mine is set up so that positive pressure is seen at about 3/4 throttle opening. i would suggest (if you have an intercooler) to position the wastegate upstream of the intercooler, this will keep air circulating through it at idle (may keep it cooler a bit) and will eliminate the SC-14's growly note. the closer the gate is to the blower, the more blower noise you will hear out through it. another option is to plumb the gate's outlet back into the blower inlet (or turbo inlet if it's twin charged) to reduce the noise. hope that helps,"

you're reading way too much into what tony has said there, he was merely using examples to illustrate his point. you could waffle on all day about how turbos are better, the same as some guys could waffle on all day about how their GM 6/71 is better. at the end of the day, remember everything in an engine package is a compromise of some sort. tony and i just have different views of what is important in a real street engine than most people do. i'll see if i can dig up my explanation post over on calaisturbo of the bypass system, i've written it all out too many times already to do it again.