Lithium

Yay I got to take my palm off my face for a post, and actually smile. This forum unfortunately has swollen nappy loads of posts blocking the view of otherwise useful or interesting dyno related posts due to people having small minds on the topic.

OK random question, but I want to confirm just from posts I've seen from Australians on other forums on this topic - with these flex fuel setups are you only using it for Flexfuel type blends? So to run E60-E90 type range... or are you able to run straight un-alcoholic 98 up to E85?

Bloody hell, that sucks to hear and is beyond embarrassing. I had just warmed up to the idea of EFRs again too

There is a guy in NZ that claims mid 500kw on pump on GT2860Rs who is a fairly respected track racer etc, which sounds like crap - even on a high reading dyno. The trap speed argument has come up but he has no interest in drag racing, conveniently.

Posts are still popping up on the Supra forums of Precision JB owners unhappy with how long their turbos have lasted.

The more significant number is the exhaust manifold pressure imho - that is the one that can wreck havoc, and if you are getting 8psi post turbine then it is potentially getting quite ugly pre-turbo.

Wow, selective quoting by first quoter - but still, very very very very VERY disappointed in what BW are doing there. Just when I started warming to the EFR range they are blatantly being crooks, that is disgusting. Understand that they are doing these housings to fill orders, but they REALLY should be telling people (and charging as such) that the product is NOT the investment cast housing version (that is one of the justifications of the pricing and the wait) instead of just supplying them with a nasty surprise.

Interesting, we find with E85 the part throttle/heavy throttle/everything gets noticeably more keen. E85 = makes the car drive like it has a bigger engine. I have done a bit of flex fuel tuning and recently we drained the tank of E60-something and put straight pump gas back in and the car felt like it'd lost its lust for life it most conditions - went fine, just with no real sense of eagerness.

^ need more info.... What is the setup? Nice result, nonetheless?

G4 Link does it fine

They have RON/MON/AKI specs on the fuels tested and the base is 91RON - same as ours, so imho too low to relate to the E85 we'll get downunder.

So you don't have any weird fuel pressure related issues at really low load with a big (300+lph worth) where the FPR would be dumping fuel back to the return?

Had a chance to read that - very interesting stuff, cheers for sharing. Glad they posted IMEP, there is a bit of a myth that I encounter which suggest there are only performance gains to be had using ethanol on knock limited setups and its nice to see an independently researched paper which isn't some workshop or whatever showing off their 1337 tuning which shows some of the general benefits from using eth blends. Shame they chose to use "91" as the base petrol.

I did some flex-fuel tuning on an S14 a while back using Virtual Dyno (unsure how well it compares with a real dyno yet - we were more or less testing the process but dyno will happen) and right off the top of my head I recall it did seem to drop off in gains quite substantially after E60, and I was also pretty surprised at the amount more fuel usage required to meet targets on E85 as well. Something which we discussed but never really formed a solid conclusion on but interestingly enough (whether this is placebo or not) despite Virtual Dyno not suggesting there was much of a difference there seemed to be a reasonable sensation of quite a lot snappier performance... not exactly a scientific observation, but it did seem like it got up and went more impressively on E85 somehow. When I next do a session of the sort (will be doing one within the next couple of weeks) I'll see if can log a few curves from different ethanol contents and put across the fuel requirement differences.

Trying to work out if everyone in this discussion appreciate the difference between injector timing and injector latency... without being on the same page then I can imagine this could get very confusing for some

^ Wow - that is awesome! Any more details on the setup? Ie power, turbo, boost?

As already mentioned, well aware that you said a turbo change is not what you are wanting to look at doing - but at the end of the day the cams aren't going to be a budget mod and are really going to make so little difference you're going to wonder why you bothered imho, and will eventually have to do something drastic to polish the turd that is GT2540s (if you don't just replace them). Honestly the most logical thing to do is change the turbos, as funnily enough anything else you do is not going to change that they are GT2540s and as such are going to behave like them.

Ah ok rereading it I see that, when you resolve it please let us know what the issue is (assuming the solution doesn't come from this thread). Will be good to see how it goes, keen to see a healthy S366 RB30 result Would definitely expect an RB30 to have something, even if it is laggy

I saw you noticed the thread I was involved with on the Link forum... your car ultimately inspired setup we did with the S14, works really well too - definitely the way to go IMHO.

Are you going to share a dyno plot comparison with the stock RB26? With a boost curve overlay would be ideal! Or alternatively do you have more info on how they compared? When do you get "full boost"? The way you communicate it (and the fact that you are subsequently on a forum asking randoms for opinions) sounds like the tuner was a bit dismissive of your concern, which suggests to me that either it is clear to them that the turbo/something is not suited to making respectable down low torque - or that you might need a new tuner who will ensure everything is working as it should be

MBT is not an RPM specific thing, and 11.5:1 is quite rich for a low compression motor running 6psi...

Nice result! Makes a really solid difference You are the guy that Chequered did the Flex-Fuel tuning on as well, eh? Would be interesting to see how the setup goes on ethanol + VCAM! Pretty cool having the combination of someone keen to try interesting combinations, and a tuner with the inclination and ability to carry it through.

Nissans are a bitch to drain the tank with, its fun being able to get 20/40litres of ethanol every now and then and just pour it in and always have some degree of ethanol blend. E40-50ish works really well and does't have so much of a fuel consumption hit, it seems left over ethanol can hang around for ages and keep your car going quite sprightly for a while. 13:1 afrs under full load aren't for everyone, give me the target AFRs and the right amount of timing to maximise on what can be got out of the mixture in the cylinder any day

I would love to see reference to the improved consumption over straight petrol - while I am no expert, I am no mug either and an immediate point worth noting is that 35% of the mass of pure ethanol is effectively oxygen which in true effect joins the "air" side of the "air/fuel ratio" when the burn gets to happening. No matter how you adjust your injector timing you won't get over the effect that you have more air to mix your fuel with and if you try mixing 14:7 parts of E85 with 1 part of air (as measured) you will be running ultra lean - the best bet I can see for making any of that up is by needing less fuel to make the same torque. That could maybe partly be done by running lean (it would have to be like 1.5lambda to match petrol @ stoich) or by making more torque for the same amount of air drawn from atmosphere. Definitely torque improvements to be had by doing this, and you can get equivalent AFRs for less IDC by dialling this in too - but in comparing between fuels one would assume the setups are equivalently optimal. The issue I have with tuning ethanol is we don't have E85 at the pump in NZ so the setups I have been/will be exposed to are all using ethanol content sensor + Link and unfortunately there is no means to play with injector timing vs ethanol %, and I tend to make use of closed loop lambda which means that whatever cruise/light load lambda targets I pick have to suit petrol as well as whatever ethanol blend is in the tank.

I can't see how it would be possible without being ruthless!?