simpletool

^^^ It looks like your front guard has hit the rubber a fair bit there. Or is that a light reflection. I highly doubt 3.5degree negative camber is ideal for road driving in a street car, even with proper semi-slicks. And ECR32, 33 and 34 get wider guards with each model. Flush fitment looks good, significantly outside the guards just looks like a virgin P-plater rust bucket non-turbo 180sx living in 2006 when drift was kool.

If you mean clean pistons and put in new seals then every 5 years or so. You can tell when you replace the pads - how hard are the pistons to push back in? You'll notice they might be very hard to move back the first 10mm then get a lot easier for the last 5mm = rebuild time. You can get by without rebuilding them but they won't work as well (won't release properly and overheat the pads or fluid during hard work). Eventually they will grab and stick all the time and you'll get uneven pad and disc wear.

It'd be some kind of multi-variable equation. Easiest guess is a percentage say 20% more at the treads. A better model is a flat number of say 25rwkw plus a percentage of ~10% The best model would be some multi-variable non-linear equation.

And to answer the original question......ie. 2psi gain expectations. If the turbo is still efficient (which it will be) and you don't hit the retarded area in the last column of the ECU map then you will make. Y = X(O + 2)/O Where: Y = your new power level X = your original power level O = your original absolute boost pressure level (ie. boost + 1 atmosphere or 14.7psi)

I have a set on my car - track rims the forged Rays ones. They are 8" +30 front, 8.5" +33 rear. Same fitments as anniversary. No need to measure - it is stamped on the inside of the wheels.

Yep, the tyres are too wide. You should go a bit smaller on the tyres.

ECR-033, at 18psi I think you are over-boosting that turbo. Better to drop a couple of psi and be happy with 230rwkw than blow the rear wheel off. I doubt that extra 2 psi is giving you much power anyway. I make 227rwkw at 15psi mid-range (dropping to 14psi up high). 4th gear with ebc = full-boost at 3300rpm (1 bar), 7psi at 2800rpm. Skylinatic, your midrange torque is amazingly similar to mine at ~520Nm calculated flywheel. I doubt you'll get much more out of the turbo though, maybe another 10hp or 20 max.

You might want to go to a twin 2.5". More muffler surface area per flow area means quieter with good flow. A truly good muffler 3" muffler with resonance chamber should do the trick for you though. There is 3" straight through, and there is 3"inch appears to be straight through - different things!

If you also change to E85 then you'll get roughly another 10% more power at same airflow, but you'll need much bigger injectors. So then you'll have the magic 450hp.

25psi is still in a respectable efficiency zone of the 82mm compressor. It's out of the most efficient zone but still ok. Peak flow here is caps out at a touch over (60lb/min) , or almost 600hp before hitting choke. If you use 90% of that flow then it equates to 440 to 450rwhp (assuming you had a larger engine). With 25psi as you stated you should get 410rwhp. Can a 0.82A/R turbine flow this 410hp? Perhaps. You should check exhaust gas temps as you raise boost. You probably won't need a bigger compressor just a bigger turbine (and total flow, so you'll also need a GT35 0.82AR). I'd guess a touch under 10% more lag ~400rpm, since you are only changing the turbine side to ~15% more flow. Why not have a look at the maps using true GT35 (3582) turbos and compare.

Any input on the comment saying E85 has lubrication issues? I can see 2 possible factors at play on this. 1. Oil dilution - can be solved by more frequent oil changes (maybe every 2500km). 2. Less lubrication on the upper cylinder walls (not sure on this - just a thought bubble). Would the higher fuel content in the chamber and properties of ethanol cause higher friction/wear - possibly by removing lubricant reside from the walls during filling/compression strokes?

As in stock internal won't allow anymore power to be produced than a 3076 can provide > 300rwkw. Forged internal don't make more power, but they allow it to be made. Dyno graphs in the thread show plenty of GT3076 at fullboost before 4000rpm.

Std internals + GT3040 is usually a mis-match. What A/R is the turbine housing? What are your expectations? What is your mid-range goal? Peak power goal? Do you want a monster or something genuinely quick and more usable? I'm not one of the experts but if you've only a got a 240Z shell to push around then you'd want a nice linear midrange with 550 to 600Nm max coming in as early as possible. The GT3040 adds more lag for no gain on a stock internal engine. I'd swap it straight-up for a GT3076 w/0.82 rear (normal GT30), run 17 or 18psi coming on full at under 4000rpm and be happy. Will the chassis benefit from much more than 260-270rwkw? Assuming you are ~1200kg then a RB25 would already behave like a 3.0L in a R33/R34, just with more revs and power up top. 550Nm in 1200kg is like 640Nm in a GTST! Having even more torque on that light rear end sounds like a recipe for no traction and slower speeds.

. Obviously boost is tapering off up top with the 19psi tune - otherwise you'd be making at least 330rwkw judging from your 13psi tune. I agree that the rush feeling usually comes from the mid-range torque and yours should be decent, say~590nm. Considering torque to weight though and that would only be a touch more than my GTST on 1 bar. So I can relate to that fast, but not THAT fast feeling. My personal rule is you need a 20% increase in torque for it to feel substantially different - but that is HIGHLY subjective. 10% improvements you clearly feel but it's not a big leap. 5% improvement you only feel if you are attuned to it. A 20% midrange difference is almost exactly that between your 13psi and 19psi. A 10% midrange difference you can test by comparing between 16psi and 19psi. If you had that 10 or 20% increase again would it be sufficient? If you think so then a E85 tune might be for you, complete with slightly bigger turbos and much bigger injectors/fuel pump. Otherwise you'll need to pump 22 or 25psi into that thing with some bigger turbos. Then again, perhaps only a slightly higher torque but over the wider range might just do the trick. Hence the garrett consideration. Did I just talk in circles? my 5cents (soon to be 10c)

Tired rings aka blow-by. All signs point to this. Check compression. ie. Pressure from combustion chamber is leaking into the sump, this is forcing too much oil up into the cam covers and out the breather pipes into your intercooler pipes.

" ."Probably not due to mid-range torque. Add full exhaust and free boost mod and you'll be sorted. See the Quick Reference Guide in the Forced Induction header. Ref Guide

In terms of chassis the R33 GTST is showing it's age. Engine wise a typical R33 RB25DET is usually modified at least slightly. Assuming some "common sense" the engine performance is usually quite good at around 230 to 240kw (and prob 380 to 400Nm) flywheel for a 1400kg car. With Nistune, AFM, injectors and medium turbo you'll get 300kw (500Nm) and it'll be comfortably quicker than any local V8. Then you'll discover just how far behind the chassis is (which can be fun as long as you have upgraded the typical suspension parts). Stock they are barely quicker than average, and slower than a Golf GTi in anything but a sprint. I'd compare a stock R33 GTST to a BMW 330ci (just without the leather, badge, or stupid repair costs.). Pretty much the same situation with the current V37 Skyline.

Any comparison with mid-range torque for boosted engines needs to take into account FIRSTLY the boost pressure. Have a look at any latter model Evo (especially the 10) and notice how it runs big boost in the mid-range and tapers massively at the top end. An Evo 9 runs over 1 bar in the mid-range and an Evo 10 over 20psi, but this falls off massively as the revs rise (this is why EVOs make such big gains with flash tuning - to level out the boost curve and lean mixtures). This is the opposite of the R33 RB25DET, where stock boost rises at higher revs (presumably to make the R33 smoother, less snappy and more GT-like). WRX which also runs a small factory turbo with high-pressure which will make big mid-range torque but run out of flow up high, plus the heads on pleb-WRX are good for mid-range not top-end. I'd say this difference in mid-range torque has a lot more to do with turbo size, variable boost pressure (in the late Evo especially) and head design than cylinder dimensions, rod-length or number of cylinders. The over-square dimensions of the RB-series (ideal for the RB26) coupled with the small turbo but low mid-range pressure on R33 RB25 was the worst of both worlds however - but this just means it's easier to get big gains. The factory's loss is our gain.

Well OK, may I didn't mean "perfectly" but yeah I couldn't hear any knock - EVER. Plus monitored with SAFC2. I can't say the same about any other engine I have driven on for years - including, shitty corrolla, RB30, SR20 tuned (several times by "the best" tuners) and current tuned RB25. Plus it showed no signs of poor mixtures or erosion on the copper plugs (that lasted 20,000km). I can usually make an engine knock somehow and hear it - even when the so called expert engine tuners say it won't knock on the road. Yes, I know the RB25 doesn't like ping.

Just so you know, I ran on the Toshi remap with Apexi turbo for 3months perfectly. Car drove well, picked up some power, responsive with good fuel economy and even Brisbane - Sydney trip was great ~8l/100km. got tuned, now have 305rwhp.

Bringing this back alive just to add that the wastegate on these turbos is adjustable stock (screw fitted arm). I got mine from Darrynspencer on here - adjusted to 9psi then put a boost controller on it (ID3) and tuned at 11, 13 and 15psi (above 13psi boost drops off at the top end a little). Full boost (15psi) at 3500rpm on the dyno and road when tuned, made 227rwkw. But boost was dropping off to just under 14psi. I think I could wind another 2 turns on the actuator to get ~11psi without controller and fix some of that pressure drop off, set controller to run 16psi and probably max out at 240rwkw.

I have also lost a LMGT2 centre cap at the track, but at QR. Perhaps one day someone will get a full set from walking the race tracks. I swapped to Rays 350Z wheels - LMGT2 are still sitting up in Queensland.

if they are knowledgeable they can tell without even looking - from the sound. Or from the badge, or the FMIC, or the rego.

I've got the HTR ZIII and they are great. I've had the ZII put on for a day as well (stupid tyre place put on the wrong ones and told me to come back tomorrow) I gave them a bit of a test and they were much worse than the ZIII. Totally different feel, tread pattern, etc. Z3's have a stiff sidewall which gives great turn-in but doesn't give much ride comfort. Wet grip is average. Dry grip is good. Feedback is excellent. For the money I can't fault them at all.

R33 GTST '96 Stock internal RB25 Nistune Apexi AX53B70 (P25) S15 injectors (450cc) HDi FMIC Z32 AFM Full 3" into 2 x 2.5" exhaust 227rwkw RPM in graph is about 5% too low - full boost at 3500rpm. 3 tunes at increasing boost - still not maxed out (but not too much left, maybe 1psi).