SKiT_R31

on the cheaper side of things, fuchs seems to keep the 30de pretty happy, I've tried more expensive oils, fuchs seems just as good as any

Yeah its running about 25% mix of methanol at the moment, I'm fitting it with a microtech LT12 though, and tuning in an extra injector for full time water/methanol injection, so i can just fill up at the pump still. also i only intend to rev it to about 7000rpm, revs generally replaces displacement for more power, that said though i don't want it to be too much of a pig down low, I'm certain ill get more than the power i want without needing to rev it further than that. Also, best cure for cam lag (or any lag) is compression and ign timing, my car still has way more down low than a standard rb30, and buckets more than a 25de (with stock vct setup, should get improvement on adjustment). But it isn't much in comparison to what its got up top, and it revs so fast in the first 2 gears compared to my turbo. Also i just love the feeling of stomping the throttle and having the rear wheels spinning before your foot hits the floor, N/A response . Also, i cant see there being too much of a power difference between one large tb and 6 smalls on the same type plenum, and I've got enough response, thats why i didn't take that route yeah Tas has no laws like that, but we're pretty strict on hooning, since everybody drives around at half the limit and as if the accelerator maxes at 10%, so if you stand out to be moving quicker than the pack on take off, and your in a modified car, your as good as gone . I'd trade no turbo for that any day power = capacity, revs, timing, tune, flow, weight, efficiency (so cold intake, cool combustion chamber, intake and exhaust scavenging, strong spark - example, index the plugs, get colder type, slightly over gap and run strong ignition) CR tip - you want the most possible practical compression on the most efficient squash (you don't want to see cylinder walls at tdc) 12:1 is doable on good pump fuel with no extras (like my water injection) i just didn't do it the best way possible the first time around. flow is obvious, bigger isn't always better, match length and diameter for most efficient velocity at peak power/air flow in and out (if you go from 2 pipes to one, they should have the same total area with a smoother transition to keep air speed with no pressure drop), match the cam. Polish it all, remove ridges, etc Remember, you cant just wind up the atmosphere, you only have the atmo 14.5psi to play with, you don't want to be lower than that pressure by the time it hits the cylinder Big power should really be a walk in the park, i mean look at dons original engine, 151rwkw, untuned, technically stock with a mild cam and extra throttle body (30 bottom, 25de pistons, all stock bits inc head, on budget exhaust, stock plenum, breathing hot air, only revving to 6k etc). 150kw is pretty decent to start on, if you cant get another 30+ kw from working it from there, there really is a problem somewhere. People just need to get back to the old, every kw counts, if you gain 2-3kw from all plugs indexed, 1 or so from polishing the inner plenum, its worthwhile doing it, unlike typical turbo modifications where its just - get a bigger turbo, run more boost, instead of fixing problems, like intake pressure drops and limited flow. also, people cant forget - its also illegal to modify your n/a engine under the p plater laws....

It should be fine to get it all engineered, just will have to match the brakes etc to that of the turbo model compressor surge happens when the TB is shut and has no effect on the engine whatsoever, if you want it to flutter, don't fit a bov and it will flutter, no different to the factory turbo motor.

have you read any of this thread?... you shouldnt need to change the pistons unless you want big power/high boost... how much of work could you do your self? (i.e. take the engine out, head off etc??) s/h pistons? otherwise how long is a piece of string

cats can be expensive, fail for no reason, some high flows can let out some off smells, plus its just another thing that could cause hastles dont gut the factory cat, will sound shitty. Replace it with a bare pipe, or if you want it to look real, weld a pipe in a stock cat (cut the ends off, put pipe through, weld flanges), personally though, i wouldnt bother. i've never heard of anyone havning any problems , its not really policed in tas, as all cats are for is to eliminate smog in cities, we dont really have a problem (thus why legal in nz). the fines arent as bad as people think they are, the mega fines are for buisinesses doing it, and police arent expected to know what cars need and dont need cats and what they look like (could put a small hotdog in its place) most likely you'd get a defect, just put one in and get it ticked off imo.

the n/a gearbox will handle a 25det just as much as it will handle a 25de+t, ditto for clutch ^ the gearbox should be ok with it, pending how you treat it The ecu has to be changed anyway I'd rather run 7PSI on an n/a engine that i know and trust, over 10psi on a random engine, to make the same power. You'll hit the ecu power/airflow restriction before you have any other problems, just the same as with the 25det, but on less boost (as its drawing in more air and making more power) Id rather rebuild the N/A bottom end with some lower comp pistons than waste money on a flogged 25det And changing all the turbo bits over is easier/less hassle that an engine swap any way imo that said, if your not attached to your car, buying a turbo model is definitely the easiest and possibly cheapest option, as brakes, etc are already upto spec just if you don't know a ot about cars/engine, get some one who does to have a look over it for telltale signs of water pump, oil seals etc, test CR etc. As if its a turbo import in Australia, its been thrashed.

Hey All, I've got a Mines ECU, it was damn good made a huge improvement, but recently its decided it will only run on 5 cylinders, nfi why, changed the ecu and everything works fine. Opened it up, everything is perfect... is there anywhere that can flash my ecu from the mines to the std? (this is for RB25DE)

not the same turbo, they are shit, don't touch them, seals are made of jelly, and they seem laggier(!?). Stick with genuine KKR. What when are you 25 boys getting the kkr430's to spool?

leave it 4wd

No way, remember - the engine is directly connected to the wheels, if its revving quicker, your moving quicker, which is kind of the whole point??? With my car, its a bit of a hand full in first and second - at about ~5000rpm+ the car just gets a double hit of power breaking traction in first (mmm sideways - limiter) (6.5" 215's stock rims) and heaps of pull in second, but in 3rd and up you definitely want it. Also, if your getting any sort of reasonably cam, you'd want a decent balance anyway, and if your going to bother with balancing it, you may as well get it done properly, all bits included, and you wont have to worry about revving it too far. to give an idea, on dons old engine as it was when i got it, peak torque hit at 5000rpm on the dot and peak power at 6000rpm, dropping off from there steadily until limiter. Thats with 2.25" exhaust and low end extractors, stock plenum. Now, short inlet runners, fujitsumoto (however you spell it) big pipe mandrel extractor's, dumping into 3" straight through, an extra ~ 1 CR (into mid 11's) power builds at the same spot but hits much harder and seems to keep making power peaking past 6000rpm and doesn't fall at all by limiter. and thats with the same mild 255 deg regrind, if you were to go a larger cam than that, she'd definitely want to be well balanced. My cars in getting sprayed atm (could take a while, side job - going to be done properly) once its out, its going on the dyno to get a proper tune (on microtech ltx12s) with a full time water injector (pulse width) so i cant wait to see what the power curve looks like

If your turboing, hold off on the cam, as n/a and turbo applications benefit from different setups, forgies wouldn't hurt if you have the money to rebuild the bottom end, but are far from necessary. I'd be spending the money on decent after market management before i spent it on forged pistons though, with a decent tune, unless your after big power (which would require management anyway, as well as other internal mods), they aren't needed.

VCT?

you don't need to have a special tune, the stock rb20det ecu will be fine, at worst you may need to lower the static/base ignition timing, but on that low boost, i really doubt it. A safc wouldn't do sfa, the only differences in tuning would be ignition, compression wont change fueling, so a safc will do the same as it would on a DET, likewise aftermarket management or retune. don't do this, why bother building up a 20de+t if you lower the compression? you may aswell just rebuild your blown 20det if thats the case. As for thicker head gasket, noooo it will do more harm than good, you'll lose power and it wont lower the chances of pre-detonation, they should really only be used if you shave too much off the head/block as a spacer, but n/a and turbo pistons run a different shape and squash, a thicker head gasket will ruin that squash. shouldn't it already have them, the same as the turbo engine? I know the S1 RB25DE does, as does the RB30e (r31 spec), i would have thought they all did. i wouldnt worry about this, you'r not pushing big numbers, if you run more boost than the det injectors can handle, you'll need to upgrade a few other things, i'd add these to the list then - if they are different. I can see the engine coping easily with enough boost to max the injectors (done on a dyno with ign timing adjustment) The difference is, the 20de will make the same power as a 20det with nearly double the boost, so I'd be more concerned about the amount of boost more to make sure its getting enough fuel. on top of that, make sure its getting good fuel, and cold air. this is a really good idea, not because of the less boost protecting the n/a engine, but because the turbo is otherwise too small, it will max and generate too much heat etc. the 5-7psi actuator on the 20det turbo should be ideal, when time to upgrade maybe a whole 25det turbo would be a good choice (as spool wont be as much of an issue). nope, your inter cooling it, just make sure its a decent cooler, like a fmic and you run it on decent petrol, you'll find that turbo will be a bit small though. people seem to forget, compression is your friend, and you don't need boost to make power, compression makes power, so you'll make the same power off less boost, obliviously because of this the boost limit is lower than that of a low comp motor. for example, an rb20det with 15psi has the same static compression as an RB20DE+T at almost 10psi, An rb20det @ 12psi has the same static compression as an RB20de+t at ~ 7psi etc So technically with the 7psi actuator the 20de+t will run a bit higher than a factory rb20det static compression ratio, and will probably make more power. Also dont forget this is about the boost that actually makes it to the engine, the actuator gets its reading from the turbo outlet, between there you'd got a lot of restrictions that can cause a pressure drop, so you may see 7psi at the turbo, but only get about 5psi in the cylinders etc. With the higher compression, (but similar with normal motors) flow is going to be what you'll want for power, the more flow you can get at the certain pressure the better, so cold air, bigger turbo etc. go for it, good luck

hah, cheers - yeah I've got some vids, nothing decent though this one was filmed by the other guy at the drags, i just randomly found it on youtube. Its a test and tune drag day, and thats what i was doing, it was a hot day, and on my first run i heard detonation, so this is my second run, where i wound the timing back to ~ 5 degrees BTDC (retarded) and increased fuel a bit too much (esp in top end as you can see), i short shifted third and the car just bogged right down, thus the bad time. - Car had to sit in line for like 15mins which killed the temp on the bad cooling/intake system. http://au.youtube.com/watch?v=dWUEvS9a3Hs This one was filmed by my drunk girlfriend (lol dont ask) on her phone, i must have nicked the indicator (cant hear much with helmet) so i didn't realize it was on, lol - got it half way down the strip... This was one of my quicker runs, and was after lunch, the car had been left to cool a bit, had between 5-10 degree's ignition timing and still pretty rich http://au.youtube.com/watch?v=dzsZxrK1mSc I love the first vid noise, you can hear how tame the engine is, half throttle and it just holds the revs perfect, mmm.... miss driving her...

Heres my muppet, was untidy in this picture, hasn't had any external love for a while, though it's lined up for a full body respray, in a similar blue, bit more metallic, brighter pearl, etc. mods are RB30DE (25/30) don's old engine, pulled 151rwkw as it was (with only a couple changes - a/f mix, timing, y piece). Now nothing like that, whole engine has been appart, head done, cams adjusted, mines ecu, fujitsumoto (sp) 3" extractors and mandrel exhaust, fpr, bosch 023 pump, 370cc injectors, AFC neo, increased compression to 11.5:1 running methanol blend. (thats as it was at the drags) Engine currently undergoing a deck shave to as far as possible, to hopefully take CR up to 12.5-13:1, removing hot spots etc. Combining this with full time water/meth injection, and a microtech ecu - for pump fuel and high ign timing and compression and lean a/f mixtures, plus a 90mm tb and ff plenum with cold air ram straight from the plenum through where the battery normally sits (wont get heated by exhaust etc) plenum is insulated to stop heat soak from coolant, and has an insulated spacer plate as well, so it is always icy cold... Car has temp controlled elec thermo fan, 52mm triple core alloy radiator, silicon + high temp/pressure hoses with hd clamps for high pressure. Still trying to decide on whether or not its worthwhile balancing the bottom end atm, i don't think it was ever done, the engine pulls hard and peaks at about ~ 6200rpm, and holds power until 7000rpm (where i wont rev it any further). It'll be a costly exercise to sent it away for proper balancing - still weighing yay or nay. I ultimately want to hit 250rwhp, which should easily be achievable i think. other mods... interior's pretty schmicko, its a Ti so blue velor and full electrics, with manual conversion. It has Excedy HD organic clutch and billet steel flywheel, RB20DET gearbox, singlepeice tailshaft, 3.9 diff gears on locked diff, stock rims and tyres (for now, got some nice 16" BBS meshies on the way, cant wait) and stiff customs springs and shocks (and custom struts) full polyurethane bushes through out, HD front and rear sways and strut brace, weight has been moved around a bit, car sticks like shit to a blanket, it out handles me on the road (even with stock rims, good tires) - meaning it'll corner faster than i want to. Runs slotted and cross drilled DBA4000 disks and green stuffs pads with braided brake lines, never let me down, i'm not a fan of un-necessary braking power, It'l out power any tyres i give it and never experienced fade, the day i do ill upgrade. (bigger heavier brakes kill acceleration). Drags it only got a low 14, only had a couple runs and temp was an issue (had to wind a lot of timing out of it and a lot of fuel into it) plus i couldn't get traction on take off, first gear was only good for ~ half throttle clutch slip. I've now got some exchange rear struts with taller soft springs and reasonable shocks for some squat for traction (combined with better wheels/tires) for a while down the track when it see's the strip again.

Make sure the igniter is earthed properly (bolted down, maybe with a proper earth wire connected also), I've heard of them severely retarding if not earthed properly. To move the timing to where it wont bolt, you need to take the CAS off, turn it as far as you need then put it back on

a different cam should have nothing to do with bottom end??? an auto or manual engine should also make no difference, just change the flywheel over. But for 4WD the sump will be be different between the 2. I'm not sure if there are any other differences though. Also, i severely doubt your cars done 160,00 original kms, double it and you get a more accurate amount its probably done... "checked it and its fine" how exactly? You'd prob get more help in general questions as this isn't really an N/A specific topic. what were the results from the compression test? You said 35psi down on cyl 5, but compared to what? 4.2L of oil is a lot for such short distance, sure it doesn't have a leaking seal as well? Does it actually blow blue smoke? If i was in your position, i'd be more inclines to just rebuild the old motor, new seals, rings and bearing, bit of a block shave (you could safely bump the CR up .5 or so for a bit more go). Car will go better than ever, and you wont have to worry about any of it again.

It really goes more by throttle and load than revs, for example - if your shifting at 3000rpm, and using half throttle to accelerate on gear change (to pull it from ~ 2000rpm to 3000rpm again) its actually more efficient to rev it to 4000rpm using less throttle. i.e. its more efficient to rev the car at 4000rpm on 1/4 throttle than at 3000rpm half throttle, as the motors in its power/torque. The idea is to use less acceleration, if you go revving it to 4k on half throttle, it'll use more petrol. When I'm tight for cash or babying the car to make it to the servo, i just drive as if 10% throttle is WOT, so if your in low revs and the car isn't accelerating, shift back. its all about airflow, more air = more petrol, so the more air your letting in, the more fuel can be added, but at the same time, the higher its revving, the more air thats is sucked from the same throttle opening. There are other variables, like high load = richer fuel mix, too high revving will make too much friction etc. I usually drive with a fairly active throttle, fairly heavy on take off, but as the engine revs & power increase, i keep lowering the throttle, so the engine essentially holds the same power. But at the same time, i have my fun and give it the stick fairly regularly. On my last 2 cars (both N/A RB30's, one auto one manual) i happily got 550km till fuel light (about 50-55L) this includes a fair bit of hwy cruising though (to and from work). I don't know how your getting such bad economy, check your 02 sensor, clean or replace your coolant temp sensor, don't thrash it when its cold (richer fuel mixture), if all else fails, get a safc tuned lean on the dyno at low throttle, should be safe.

I was gonna mention this, but wasn't 100% sure it was true

turbo is 9:1 CR, N/A is ~ 10.2:1 CR, achieved by different pistons. Cams are the same, i think just on the turbo the exhaust cam gear is shifted a couple degree's. Thats the internal difference, external theres the Injectors (370cc vs 270cc), ECU (to power injectors + different map & limiter), obviously different exhaust manifold, intake piping, things like clutch is different, different gbox.... thats about it...

i really don't think that compression is going to be a problem, and decompressing it wouldn't really solve anything except kill some of its power, you should really only use them when you've shaved a bit much off the head etc. Look at Juddo with his 25de+t, didn't stress it in the slightest, and he only ran 95ron, but on like 10PSI, everything stock. On stock boost i really cant see it complaining at all, esp with a good fmic, i wouldn't worry about richening it up (rich enough from factory), maybe wind some base timing out of it, but still would be fine. If you can run 7psi through a 9:1 CR 30e, you should definitely be able to run 7psi on a 10:1 CR with a good cooler. as for the throttle cable, cant you just use a std RB30e position one? thats all i did for my 30de, got a thick flat bit of steel, few bends, drilled a few holes, added some spacers and made one shmicko, looks way better than stock, sits at perfect height. When i fit my ff plenum i prob wont need it actually...

Sounds like it'd be spot on i wouldn't run a thicker head gasket, doesn't solve anything. It'll make good power on stock boost (7psi on a high comp 25 should eat a 20det on over double that) DO EET but good luck finding an R32 25DE, everyone snaps them up for 30det conversions Theres no reason why you couldn't use an R33 rb25, you could hook all the same electrics up (you don't have to have a plug for vct it will work fine without it) you'd just have the plenum issue - I'm not sure how different they are, if its just port sizing i wouldn't call it an issue.

they're shit, get a proper kkr mate had a jjr480, it f**ked its seals after a month, and wasn't very responsive. sold and bought a kkr560, it spooled earlier, felt smoother, he's running twice the boost ('race actuator') and has had no problems.

its possible... you really need a decent tuner, lean the car out (into high 13's flat 14) at low throttle, and under heavy throttle/WOT as lean as possible without your egt's getting too high. alot of tuners are scared and live by the doughy rich 11:1 'safe' tunes, a decent tune with a decent engine should be able to hold 14:1 at WOT on an N/A. (I know of a 500hp n/a that ran this) so hunt a good tuner, not a 'drift' one, maybe somone a little older, into motorsport, and lean away giving it as much timing as you can, that alone should net you a fair bit better economy. Also pushing it into closed loop as often as possible. ontop of that, you could run even leaner, and run water injection (water is free) to cool your egt's - im currently playing around with this for my 30de (alot of timing, high compression and lean a/f mixes).

it wont effect anything cheers