burn4005

you're right, I haven't found anything that explicitly states the 80mm turbine rpm limit is what stops you spinning the 91mm compressor wheel any harder, but Borg Warner saying the 9174 has a higher HP capacity and rpm limit relative to the 9180 shows this is the case. what confuses this is all of borg warner compressors are limited to 560m/s tip speed, and it is definitely the compressor tip speed they're talking about, so why the 91mm compressor is an exception to this is anyone's guess. it appears they have clipped their compressor map at this speed, so the 9180 map stops at the 116krpm line, but it's actually still operating at 70+% efficiency, so if spun harder you could extrapolate that map up and to the right a fair bit further if the compressor can hold itself together. you'll need quite a high pressure ratio to keep it happy though (anything under 4:1 is basically stonewalled).

compressor stonewall is a mechanical phenomenon that cannot be avoided. In turbo land garret just shows the choke line, whereas Borg Warner actually show the RPM stonewall where each constant velocity line goes vertical. once the constant velocity line goes vertical the compressor is done and something is running at unity (sonic) in the compressor so she won't push any further as it's choked. you'll notice most turbos with the same inlet size are rated to similar flows. this is because the inlet cross section defines the maximum flow of the compressor. clever forged/cnc compressor wheels with the same inlet diameter but smaller centre shaft areas have a bit more because the cross sectional area available for flow is higher.

Maybe so, but you can only do so much with 78lb/min of air, its written right there on the freely available compressor map. and if your target was more than around ~575 flywheel kw you bought the wrong turbo. So 500awkw means a very slippery gearbox/tcase/diff

oh a product with clearly stated design constraints, lets operate it outside those parameters and complain when it fails. its like buying an engine built for 8500rpm and running it at 11,000 then going off at the engine builder when it throws a leg out of bed. people are so used to the american performance market way of doing things, no tech specs, just an arbitrary power rating and do what you want.

That new nulon racing oil is f**king pricey when you need 10l of it for an oil change. I just buy 4 bottles of Penrite racing when supercrap/repco have their big discounts racq etc. Ducted setrab oil cooler means 10w40 is enough for a 4 /5 lap sprint.

I had to cut along the inner edge that the two oil hose connections go on. the setrab series 6 is about 5mm too tall to fit in the ducting. so the whole top edge of the cooler (with the ports on it) sticks out of the ducting towards the engine. its actually about 1 row of the cooler. I have no more pics, car is back together will all ducts/shields in place

Hi Mate, could you elaborate on the "it actually caused more problems than it was worth" statement in your post above? interested to hear what issues you had

one simple thing I should bring up is you know that an internal gate actuator vs external gate actuator has the ports the opposite way around? also you can check the diaphragm or shaft seal of the actuator isnt leaking. you can suck on each vac connection to the gate and confirm it holds vacuum against your tongue. you can also test the solenoid valve works by blowing into the COM port while giving it 12v. it should switch from NO to NC. it should be plumbed like this: Compressor cover port -> TOP Actuator port Compressor cover port -> NC Port of Solenoid COM Port of Solenoid -> BOTTOM Actuator port also, you should be able to feel the solenoid buzzing during a dyno pull, but if your boost target is 26psi and that is your spring pressure, dont expect it do be doing much to only hold a 26psi target. if the above is all good, I'd be looking at your boost controller settings and then leaks. to rule out a mechanical/pneumatic issue I'd set an ECU boost cut as a protection and then wind up the boost controller so its output was 100% duty (assuming its working). alternatively just bypass the solenoid and connect the boost line straight to the bottom port of the actuator which will hold it shut. then CAREFULLY use the throttle to control your boost during a run and see if it still tapers off or you can hold it. probably wise to do this on a dyno. if the gate is then definitely staying shut and you still can't hold boost you've either got an exhaust manifold leak or a boost leak. but I'm confident that isn't your issue.

Amayama.com would get one to you within a week. 99usd+ postage.

Great You can be the guinea pig then! But being rwd you should be fine. They kind of act like a drive line fuse, you don't have that luxury with AWD. Thanks for the feedback guys. If 3.2ish managed to get one to hold on his car for a while before killing it, a 2.6 with 15-20% less torque should probably last. Youre right. The question should I have been who's making 900+ NM peak torque a on a coppermix but most people only know their power figure. The plan is to keep the midrange torque In check to keep the gearbox and shafts alive anyway, and I have learnt the hard way that a super strong overkill clutch (RPS carbon) just breaks other stuff in a Evo. Will have a look at the r3c, but the fact the centre isnt sprung is worrying drivability wise. Cheers.

Anyone with a coppermix competition twin plate holding 500kw? As per title, got a new efr8374 on an rb26 and my current normal coppermix twin Is worn out and no longer doing its job. Will a competition version hold 500awkw? That's really the most it's going to see with this turbo and its such a friendly twin plate I'm inclined to stay using one.

^^2nded. I've got a tomei pump and have just put on an accurate oil pressure gauge. runs around 100psi at 5000rpm hot. 15w50 oil, oil cooler sits at 82 degrees unless on the track. considering dropping to 10w40 or removing a shim from the tomei.

its frustrating that no compressor maps are available for precisions because a turbo compressor power rating is usually based on an efficiency below 58% or even the stonewall flow (flow choke) of the compressor. this is the speed that part of the assembly reaches sonic speed and flow basically cannot be increased any further by spinning it faster or altering the downstream pressure. thats why the choke line is vertical in a compressor map. (although note that maps from garret state efficiency below 58% is the end of their displayed map, and they consider that point "overspeeding") It's not necessarily when it wants to fall apart, but the efficiency falls over and then finally the compressor won't flow any more due to sonic shock waves inside the compressor inlet or volute causing a choked flow condition. its interesting that the Precisions seem to be happy well past the flow the manufacturer rates the compressor for. whereas Borg Warner made their turbines strong enough to cope with the choke speed of the compressor they paired it with and not much more as its outside the design parameters.

hmm interesting. is that 10.3mm lift the Net valve lift or the lobe height? (ie including the .25/.30 cold lifter clearance)

Lol what.. 760 awhp on a turbo rated to 705hp.. not questioning your results but that is going to be overspeeding by like 30% Very impressive that it's still happy pushed that hard. I'm interested in your exhaust back pressure and compressor outlet temp numbers.

Came from -5s. No contest.

unfortunately no sensor, will be doing further dynoing soon to improve TPS boost control, throttle enrichment stuff and Map the atessa duty to a torque split ratio value. I have a sensor on the turbo now. will FINALLY also get some high speed logs (100hz) of turbo response off boost, between gears, coasting high rpm to WOT etc. i think we're all due for those numbers after 7 years of talking about the response of an EFR!

engine is 2.63l (87mm) 1.05 rear housing, about 30psi and full boost reached at about 4700rpm. could probably lean on it a bit more timing wise up top and a bit more to do on cams (260 poncams) 6 boost single waste gate manifold with divider to the valve face. quite similar result to FAT33R.. I suspect he's making a fair bit more up top due to the screamer.

9174 is going on a mates car, Nitto 2.7 with head work. engine should be done in a few weeks. I've got ~460awkw on the 8374 on my car and that's enough for me, my getrag and my clutch for the time being. but if the 9174 turns out to be a no brainer then I guess I'll be doing it too eventually..I'm holding off for a black series 8474 for the time being if that ever happens.

quick question for those running an 8374 or larger, got the 8374 running a few weeks ago and mine makes a bit of a siren sound during low rpm spool that I'm used to with things like HKS T51R turbos and the like, but is the siren sound normal on the B2 Frame EFRs? sounds like the full race R14 in this video but not as loud. That sound to me if it was a non anti-surge cover turbo would signal a damaged turbo. looking around youtube it appears some do it and some don't, could be camera mics or something I guess?

Vcam looks to be a good idea on a 2.6 with a 9174 to keep it out of surge. The extra VE at lower rpms will help keep it to the right of the surge line.

got a cast CHRA core, I already have a 1.05 A/R housing to suit. I'd rather not post pricing on a forum as they don't list 9174s on their site and I've had to deal with customers that have said "someone on the internet only paid X" suffice to say it was cheaper than anyone in Australia or the USA could get one to me incl. postage. which was a nice suprise!

Just an update and a huge thankyou to Lithium, I've been trying to get a 9174 for months without success but these guys came through with the goods immediately. cancelled my sparesbox order as they were hopeless. the guys at NZ performance are absolute legends. ordered on Thursday from NZ, turned up in Brisbane first thing this morning. wanted to wait until I had one in my hands before commenting though! I'll be ordering more bits from those guys 100%.

having a real hard time sourcing a 9174 super core either cast or alloy chra, doesn't matter which. anyone have any leads?

I bang on about this a lot, but find a 12watt solendoid MAC valve, its useful duty cycle range is much larger than the 5.4w version and gives more granular control (which is important on a 4 port implementation) ebay "MAC 46A-HIGH FREQUENCY"