Lithium

Forced performance use the rated lb/min flow of the compressor for their naming... So GT30 turbine with 52lb/m compressor. Their FP3065 is more like a GT3040R. They run the familiar .60a/r antisurge compressor cover...

Dredging up an age thread - I haven't found any evidence of reference to it so I'll assume it hasn't come up.... from what I understand, the FP3052 from Forced Performance in the States which is frequently used on EVOs is effectively a 52trim GT3076R and they are pretty easily obtained.

A 4cyl running 6s inferior? Got a bit of confusion there? Loving the Pantera background music.

Oh oh oh PLEASE have it run at an NZ meet before you leave

Sorry - hard to be light hearted on forums... It wasn't meant to be as snarky as it looks. Its a bit hard to get a hard fast rule on wastegate sizing, something I've been struggling with myself. There is another guy aside from myself using a 38mm on a GT3076R who has boost creep on this forum. He has a .82a/r turbine housing but is using an XSPower manifold. I am using a factory exhaust manifold and an internal gate style turbine housing with my wastegate mounted off the 38mm internal port. I've definitely not ruled out that there isn't enough flow getting to the wastegate, but I considered it worth noting.

Well no kidding, but how do you define what too small a gate is? That rule you said seems a bit too much of a blanket one. If you ran a T51R on a 4k I doubt you'd have issues with overboost, even with no wastegate.

How does that work? All a wastegate does is relieve pressure from the turbine housing effectively - isn't it? I'd have thought it'd be fair to say that a large turbo, especially with a large turbine housing on a comparatively small motor running low boost wouldn't need much of a wastegate at all. Back in the day didn't turbos not even have wastegates, and the sizing was basically done such that they just free boosted - you lived with whatever you reached if you gave it the beans. For what its worth, my car has issues with boost creep (still ) with a .63a/r GT3076R and the thing falling over high in the revs is DEFINITELY not an issue I have. Running a .6bar spring it has hit 20psi by 6500rpm and was still climbing.... hmm...

Well, it'd have to spin fast enough to move more air than the engine can - which is usually quite a bit... so until it is moving more than the motor would pull through, its actually a restriction

0-200kph is an odd kind of requirement - but for 700hp, and for under $2k... http://www.atpturbo.com/Merchant2/merchant...tegory_Code=BCS

No need to preach to the converted - there is no replacement for displacement Just convince the RB20 people that the same thing applies to them when in comparison to an RB25, to an even bigger degree I'm happy with a 2.5 in the meantime, because just because a monster can beat it - doesn't mean it ain't quick.

Oh sorry, missed that.... my bad

The TD05 is a bitch to fit, but for what its worth - its a fair bit better than the stock R33 turbo. A mate of mine runs a TD05 16G from an EVO 3 on his RB20DET. It DOESN'T spin the "wrong" way, has a single pulse turbine housing, spools about the same on the RB20 as R33 turbos spool on RB20s - but flows an absolute crapload better up high. It hit ~200rwkw without trying too hard.... They run a much larger turbine wheel than R33 turbos, and a slightly bigger compressor wheel - I'd say they'd have to be easily comparable with an HKS GT2530 in terms of power and spool.

He is right but there is some stuff missing from the story which is worth knowing. Link ECUs only have 4 coil drivers, so the way that it deals with your 6 coils (I had this issue too) is it fires 2 at a time - much like you do with wasted spark. One will be the one which is actually due for an ignition stroke, the other will be going into exhaust stroke. If your coils are getting "tired" then even if it was all working fine before putting the Link in, when they have to go double time due to the Links way of getting around of too few coil drivers they will show their weakness. Only way around it is new coil packs or the more logical way which would be to convert to wasted spark, seeing as thats how the ECU is treating them anyway.

Nice thread dude, enjoying all the WMI info as well - starting to make me think Do you think the initial spool is completely to do with the compressor design, considering how much the restriction of the RB25 turbine housing has been referred to - maybe the "tight" nozzle of the RB25 turbine housing is a lot more of the reason for your much lower power figure, and also better response than the shift from 52trim 7 blade to 56trim 6 blade? Obviously the 6 blade is going to have greater pumping efficiency, but shouldn't it have a bit less inertia as well? Just questions - not debating one way or the other

Nice result man After having both the 7-blade and 6-blade "GT3076R", which do you prefer overall? Do you think the top end power justifies the extra bit of "lag" down low? What I notice about mine is its reasonably spongy below 3000rpm but then it pics up in a big way above there, so in my opinion is very liveable - I associate that kind of power delivery with what stock R32 GTRs are like. Makes me want to get an >1bar tune

That sounds about right, I've been in a car with a .63 GT35R on an RB25 and ~1bar at around 4000rpm in a high gear. Closer to 4400rpm with .82a/r.

Should look up the VK45DE engine 253kw stock from a 4.5l quad cam V8. With a few boltons and some tuning that picks up a lot - imagine that in an R33 GTS!! Solid 12s NA....

193rwkw sounds about right for those mods on a lot of the dynos you get over here - think of different dynos as different measurement standards. Stick to the same one and it SHOULD read the same.

WTF? I suppose you guys are flooded with the crappy TO4S GT3076Rs, my RB25 starts building boost quicker on my GT3076R than my mates GT3582R does on his RB30DET.... his actually starts accelerating harder earlier but thats more to do with it being a 3litre in an R32 than the turbo match to the motor. The GT3582R does take a bit of spinning to get going on the 3l, has more of a "big turbo" feel than my GT30R which feels more like a stock turbo.

Yep this is what I running, @ .8mm

That is very very impressive power for an RB20, has a nice good power band. Looking at that I tend to agree, at least if you aren't using it on the road - bang for buck looks like a matched turbo in an R32 is a good way to go. A GT2871R should be quite nice on one as well. Nicely done

Falls off chair

Argh if you ever are in NZ, let me know and I'll take you for a drive in mine I understand your theories, but thats all they are. What really matters is how the car ACTUALLY performs. You're saying what will provide said driving experience, I'm saying mine does it. I could probably match if not out accelerate a stock R33 GTS25t in 5th from 100kph, and the car makes solid power up to 7000rpm - what more should I be aspiring to? I'd love to drive a car with a GT3071R or 52T GT3076R to see the difference, but as it is my combination is one of the only GT-BB GTSt Skylines I've come across. Cubes - I like your concept Very cool.

Definitely agreed... OK - just curious, have you actually ever driven a RB25DET powered Skyline with a GT3076R or a GT3071R fitted?

I've not driven in the last couple of weeks (under going further mods), but I'm pretty sure positive pressure is from ~2000rpm - if it weren't for the whistley turbo passengers reckon they'd not know they in a car with a bigger turbo... you definitely feel it building boost in the 2000-3000rpm range, maybe not so much in 1st - but it goes past too quick to notice.