Kinkstaah

But this is on the full race website, on a 2JZ Supra running 20psi. This is a 7670, 1.05. It's not rolling over at the top. I wager mine would actually be similar to this, but yes just guessing. Given when testing boost I was able to hit 32psi (oops!!) at the same RPM that the spike ordinarily would happen (i.e, comes on boost) Closing the gate, knowing its damn closed (hence 32psi) doesn't bring it on any earlier. It's also worth knowing that after this 32psi experiement I blew off the hose that runs between the plenum and the idle control. All the others were secure, clamped, don't appear to be leaking etc. Will obviously double check VCT and such on the dyno, but I really think it simply is working as-is.

Having a look at a 9174 (when they were all bought) the rear of the 7670 1.05 is actually basically the same damn size. I am sure at this point an 8374 would do what the 7670 does but with just more power tbh. The delivery of the thing belies its "lag" as it really does just get on boost and keep pulling in a very linear, very stable very unrelenting fashion. There's no power skids here (almost, though!) and personally I like that. If I did have monster midrange, I would have setup boost by gear to effectively create what I currently have. The target was always about 350kw running moderately lazy because I have melted manifolds and rear housings in the past at the track - so I suppose I have this and it fits the bill. It just feels a bit agricultural to be using open loop, but in the grand scheme of things I had to control the controller manually to get the result. Will have a dyno result in about 3 weeks when it goes there and shall test the accuracy of my butt dyno.

It's a full progate. As more testing unfolds (i.e line directly to gate) it's starting to really look like the boost threshold is something I have to live with. It will spike when running directly between compressor housing and bottom port of wastegate with nothing else attached. When it wants to spin up it really will spin up. Suppose it's just a compromise from choosing the setup I ended up choosing. Looking at the exhaust housings back to back is pretty telling, and I chose the turbo so it wouldn't be maxxed out/overheated/choked etc, so I ended having that at the expense of less power and more lag relative to the Garrett Option With 0% duty cycle it (boost) behaves the same as being connected directly to the turbo with nothing in the middle of it. This will cause boost to come on full at about 4500rpm (3rd) and peak at 15psi, I've then fed in duty cycle to continue it to climb up to about 19. I'd change the housing at the rear, but there is no housing to change to. Being RWD perhaps there's not much sense having 20psi at 3000RPM anyhow.. car feels pretty planted and on the edge of slip all the way through the rev range so I suppose that's also good. Still think the 7670 EWG (1.05) would be bad news on a 2.5 with that housing though. OFC if someone buys one and has wildly excellent results then I'll go hunting for fixes again

This morning I did exactly that, and run a line directly from the compressor housing and the bottom port of the 50mm gate. Drove to work, will post logs when I do some actual testing. Response felt about the same and it made 12psi pretty solidly, at least as much as you can see "solidly" when looking at a gauge and not at the road. Just for Geoff, it's a 7670 with a 1.05 rear on a 2.8 with VCT. The housing is really massive. The below picture is a comparison betrween the EFR (bottom obviously) and a GTX3582 with a .82 rear.

Alright I did some more testing as promised, and you can see what the logs look like below. First three small runs I had the controller setup as a 4 port mac. Last two I disconnected the top hose, so boost isn't being fed into the top chamber. As you can see there's more duty cycle there from the controller - So that may be just inducing a small boost leak into the system. In any case you can see how the controller does drop off from 100% to ~20% duty cycle, there's clearly a delay and a spike. This is with the controller being told to stop going 100% 6psi before hitting target boost, which is 18psi. Note: These pulls were in 3rd gear. The first 3 were up a big hill, (obviously me backing off as boost was spiking out of control) as was the last one. I moved the source for controller from my charge pipe just before intake, to the compressor housing, but it doesn't seem to have made much difference in terms of responding quicker. boost.csv

Yes, it's running a 5in cat in there. I can try and post a log, but it'd be a day or so or two or three weeks before doing that because not so easy to organize such a run lol. However there is no table for transient timing advance on the PS2000. So the timing is going to be what the base map is specifying.

It's a 6boost T4 TS Manifold with a 50mm external gate on it. I think the merge is pretty shitful to be honest, but again, not the only one running a gate in this manner. I am using the BOV internal to the EFR itself I attached a picture of my exhaust merge. It is a 3in from the dump, and 2in from the wastegate that merge into the 3.5 section after the cat. I have used this with the controller off. I had all of this setup in the past with a GTX3582 making 420+ through the auto and downsized to use a smaller turbo with the EFR. I was able to run as low as 4psi with the GTX3582 with a gate off the turbine housing, so I know the controller works/is disabled when everything is zeroed out. I did get boost spikes back then too, way way WAY worse, which I had assumed happened when loading up the car through the converter in a high gear. But now manual, now EFR, similar problem. Trying to run low (18psi) boost is some tiny amount of duty cycle, which I can only assume is a byproduct of 1.05 housing and 2.8 and a small compressor. The 5 port I have because I've always had it. Scottynm35 provided it way back in the day. The only difference I can see is that it has 2 exhaust ports instead of 1 - It still runs off 2 wires like any other boost controller connected to a Haltech PS2000. I suspect it's setup related, that the gate angle is just crap and a "big" motor spinning a "small" turbo on sharp opening of throttle, perhaps a little 'worse' given how responsive/transient the EFR is.

Guess I'll have to do some investigating. I know for a fact the lines aren't fked or leaking because sadly they have been checked 500 times over the years, and I just checked them in the carpark just now... Car is going on the dyno when I come back from overseas, so will actually post the result then. Keen to see what the difference between auto and manual truly is. Note: I have a 5 port mac solenoid, with 2 vents, (IN, A, B, EXA, EXB), but from all accounts it appears to be plumbed up correctly. Oddly enough, Fullrace sell a 4 port which I'm assuming functions the same, https://www.full-race.com/store/garrett-turbos/full-race-4-port-boost-control-solenoid-1/ However they list two different configurations for plumbing, one for EWG and the opposite for a Twin Port IWG setup, which I always thought effectively behaved like an external gate. Worst case I play with it on the dyno and see/replicate the spike and just enjoy more midrange

I have a 7670 and personally reckon it's a big big for a stock 25. I have a 2.8 and wished it was a little more repsonsive, I don't think i'd be happy with it myself on a 2.5. My vote is for a GTX3071, but if you demand specific power and only have access to 98, you may need to have some lag to get there.

Yes, it does the same thing, but sharply opening the throttle, when the system is already under load/under boost makes it all happen much more severely. Happens in open loop, closed loop and well directly connected. Open loop is 'easier' to manage because you can just hard set the duty cycle of the controller as opposed to using PID settings which are really hard to calculate when the boost is just doing whatever the fk it likes and won't behave consistently anyway. It could be the gate setup, but it's a 6boost with a 50mm Turbosmart gate. There's nothing overly special about it. Maybe this happens to everyone and I drive like a spastic.

If I do a pull from 2000, it'll spike a little. If I load it up (hill, whatever, and punch it/transition from 50% throttle to 100%) it will spike much much more, it's entirely reproducible actually. The way to 'manage' it is actually to really make sure to really, really rev out every gear, or run much less boost than I wanted to. Neither of these are really optimal... Given it happens with the controller off, I was thinking it's either setup related or turbo related. Hence me asking if anyone noticed any funny business with the EFR's super happy transient response-o-rama.

It'll only hold 12 the boost controller fully off. (i.e gate pressure). If I stab the throttle in the same manner, with it running like that, it'll 12" psi will spike to 18psi. With the controller off/bypassed entirely, piped compressor housing directly to wastegate etc.

Sorry - That is MAP Pressure in PSI. Mine is a 1.05, and tbh it does spool a lot slower than a SR20 with a EFR 7163 .85. Yes, its a smaller turbo but it's also a 2.0 and not a 2.8. The 7670 is a 400-430kw turbo, I am only guesstimating that it's running in about the 360kw region at 18psi. It's not that small. Stabbing the throttle after being say half throttle does happen a fair bit, as that's pretty much right on trying to accelerate when doing about ~100-110 kmh. To be honest I am sure 24psi or so at 4k isn't really going to harm anything, it's just something I noticed and wondered if it happened to other people who have delved into their own boost control.

I have a manual in the car now. I have the timing map which is pretty conservative linked below. Johnny may find it familiar It's pretty conservative, but it's similar to what most people run on 98, though the car is running E85. The issue still exists on 98, which is why I am running E85 lol. Perhaps it is in fact too conservative? The gear changes only ever happened when I wanted them to happen when the auto was in anyhow, because it was fully manualized. I did initially put this down to the torque converter slipping and hyper spooling the thing. But it seems while the issue is lesser now, it still exists. It's a 6boost T4 TS manifold, running one large gate. I saw @HarrisRacing make a post on the Haltech forums about the same issue in a very similar car (i.e 2.8 with an EFR) saying that when he loaded up 4th gear (after a shift, coming back onto throttle) it would overboost and spike. It may just be a thing with people trying to run lower boost on these turbos, (HarrisRacing seemed to be the only one other than me) and may not be an issue as most people tend to take aim at high 20's to 30psi.

I have a 50mm gate with a Haltech 5 port solenoid, with a 12psi gate spring in it. (i.e, it'll hold 12psi when directly connected, boost control is off). I am running a PS2000 ECU. I can sort of run this in Open loop mode, but again with only very very conservative settings, which amount to basically having the gate fully open (i.e running 12psi) and ever so slowly adding duty cycle to avoid overboosting. Some of this may be my setup which is why I am asking, I have an EFR7670 (1.05 rear) on a RB28Neo - And I am only trying to run 6psi over the baseline boost, i.e 18psi. The duty required to do that is only about ~15-20% duty cycle. I would assume if I was trying to run 25psi or 30psi it would be 'easier' as the duty cycle wouldn't be going from FULL CLOSED (to aid spool) to 15% (almost fully open), it may be going from 100% to 70% duty cycle, or whatever duty cycle is required to run 25-30psi in that example. Given this, I am only getting full boost about 3700rpm, which most people would assume is kind of 'laggy' for a 2.8 with a 7670. I don't really mind the lag so much, but I do mind the overboosting as it's not consistent and it's severe. Now, a lot of people in this thread are 450-500rwkw and running 25-30psi so this issue may not be this present, or it could be a 'problem' with these turbos or these setup. Just asking around to see if anyone's got some insight here!

So um... I assume 4 out of 5 is actually epically bad then? (assuming solo driver in vehicle) If so, why even have 5 stars...?

Folks who have EFR Are you (also) having issues with these things overboosting/spiking when coming onto boost? Nearly no matter what, if I try and apply throttle after feathering in 3rd/4th (or giving throttle up a hill) this thing will overboost. Revving it out from a steady pull it is fine and will sort of behave. But stabbing the throttle results in wild overboosting, the more load, the more overboosting. Happens on gate pressure too (my gate pressure is 12, if I load it up suddenly on a hill I will hit 20+ psi), and making ridiculously conservative boost control settings results in making the thing laggier than it needs to be, kind of negating the point of the EFR if you can't quickly stab at the throttle for dat transient. I am only trying to run 18psi, but pretty much any setting will result in this behaviour. Anyone else?

I plan on using a cut out valve for my screamer pipe (which is currently plumbed in). Ideally I'd like to be able to bolt in/out the entire thing. What brand did you guys end up going for?

These are excellent ideas. I shall be doing some form of something to hold the boot up.

Originally I wanted a Nismo leather one but $180 was the cheapest I got offered, so yeah that is out. I just want something that will sit on the thread on the shifter properly, having this dead space between top of boot and the actual knob is mildly annoying. Mildly as in cheap 2nd hand OEM shifter price annoying.

I have a shift knob that I got from our great friends at Autobarn. But I legit want an OEM one because I figure they should be cheap as literally anyone who changed their shift knob ever should have one, and it'll fit nicely over the boot...

wtb stock skyline shift knob You'd think these are super easy to buy used, but no dice. No I don't want to pay $88 for a new one.

If your exhaust actually functions then put the money elsewhere

The deciding factor between PCars2 and Forza (I mean we all love upgrading cars here) is done because Forza has no VR. If you want immersion, VR is the way you go, nothing compares after that

SOLD. (yes, really)