I wanna see this!

 

For sure! I think though that Geoff would say the GTX3076 will be limited by the GT30 turbine wheel and by that turbine housing. That's why they introduced the GTX3576.

 

if thats the case then BR's HTA3076 wouldn't have made 600whp on a mustang

 

I'd love to test the 8374 against a GTX3582R but I'm not gonna buy one.

If anyone has a turbo they want to see tested against the 8374, I'm going to be doing any testing that is presented once I get the car broken in and tuned.

 

You have the TS internal gated one yah?

 

I got the single scroll internal gate. :\

 

Ok people... So I'm just about to buy my third 7670..... the oppurtunity came about and I don't think my turbos are going to be sent back from BW for awhile to meet my schedule. Idealy I'd like a 8374 TS externaly gated. (so I don't end up with 3 of the same damn turbo.) If anyone has one and wants to trade for a BRAND new (latest production run) 7670 TS 1.05 let me know.

 

i feel the same way, however most people have never seen or experienced one of these turbos so I can understand their skepticism.

Yes - you technically could use these BV50 turbos on an evo, it will require a complex control for the vanepack and I believe (based on data ive seen) that the EFR turbos will outperform this type of turbo at all but the very low RPM points.


that will be a great test

lets look at those match ratios!!!

EFR 7670: 76mm compressor / 70mm turbine = 1.085 match ratio (yay! great match ratio)
GTX3076R: 76mm compressor / 60mm turbine = 1.27 match ratio (yikes - clearly a mismatch!)

ben - i think the 8374 1.05 is the call for your car. ill be with the bw guys tomorrow.

edit: as an aside, Im planning to use the 8374 internal WG on my 2.0L evo, here is a dynochart from this twinscroll internal-WG turbo on a 2.0L k-series honda, 25 psi boost:


i realize most of you guys arent honda people, but this is easily the earliest spooling and strongest midrange of any 700+hp turbo weve ever seen on that engine and we sell a LOT of k-series turbokits to compare to..

 

Geoff you should give the link to Honda-tech. Marshall was showing me that thread the other day. Good stuff.

 

The failure rate so far honestly makes the skepticism more than earnt - I understand there have been claims that the issue is sorted, but until there is actually public evidence that this is the case thats going to be the status quo for me, at least.

I'm not sure what to make of you saying that, but this is very very misleading. Sure, the sizes are technically different but the design is quite quite different. Its like saying a Garrett T67 and an EFR9180 are basically the same thing because they have a similar inducer size. The 70mm EFR turbine is more or less the equivalent of a 60mm GT turbine in real world terms, meaning that yes - even though the GT has a smaller OD it doesn't mean its going to spool better given it harnesses the exhaust energy in a slightly different manner. If a GTX3076R is a mismatch then so is the EFR7670, and BW should be considering making an EFR7674.

Nice result!

 

mr lith - im not going to try to change your mind, but i will tell you that the *few* failures (and they are few and their suppliers issues are identified and solved) are in the minority.

you said misleading? this is BASICS, match ratios are not some crazy theory, its pretty simple... just divide the compressor OD by the turbine OD.

FYI: a garrett T67 is 84mm OD compressor trimmed to almost 80%. EFR 9180 is a 91mm OD compressor, trimmed to 74.5%. nothing at all similar between them. compressor inducer measurements typically have a much smaller effect on the overall compressor performance than blade aero or compressor exducer (rule of thumb is 75% of OD for a high performance gas engine, and 71% for a high performance diesel engine... and 1.08-1.15 is rule of thumb for matching)

ill be away for a few days, carry on!

 

The job of changing my mind isn't yours anyway, I don't get sold things by impressive claims and theory only goes so far - I'm looking at the world to see how these things behave when they join it in sufficient numbers to generate a more positive trend. There have been a few people receive their turbos on these forums in the last couple of weeks or so, they're all the new range so I'll treat it like a clean slate. If one of those fail, then its BAD. On the flipside, despite what it looks like I'm actually unbiased... I don't expect miracle results - so if they all match or better existing turbos then I'll give them the credit they deserve.

If you hadn't noticed, I was actually the person who started the EFR thread on the Skyline forum, and have been keen to see them succeed as in concept they are really good - I am just a realist, and to be fair if it was anything other than a minority then that'd be horrific... the problem is a 40% failure rate fits within the definition of "minority", which is a worse failure rate that I have seen for people I know running $350 ebay turbos.... and at least the results I've seen so far vs failed turbos, the failure rate has to be pretty near that amount.

Aerodynamics is no crazy theory, otherwise it'd be easy to make the perfect turbo - it would be two discs connected by a shaft with the ideal OD ratio from hotside to cold side.

Garrett T67 = 67mm inducer
EFR9180 = 68mm inducer

Inducer size must have at least a tiny effect on the whole thing, considering the fact that race classes with turbo size limitation are defined by inducer size. Most people on here should know roughly what the difference between a TD05 16G, TD05 18G, and TD05 20G is....

I think you'll find that the overall performance is as a result of all design, the height of the wheel, the wheel design, the inducer and the exducer will all play their parts.

For other peoples interest - an EFR7670 turbine wheel compared with a GTX3076R turbine wheel:



An interesting comment on those pics from a pretty switched on, unbiased lad who has played with a few Borg Warners:

I'm betting a EFR7670 turbine wheel isn't going to flow 16% more exhaust gas - nor is it going to be 16% laggier. Taking all factors into account is probably a better way of comparing two turbos then just a magic rule of thumb ratio of a single measureable item on two turbos. So far the FP GT3076R HTA appears to be a more impressive unit from results Buschur has posted, and its running the 60mm turbine - so the GT30 can't be that awful.

 

i respectfully disagree with some of the assumptions you posted above. of course inducer will affect the system, thats why i posted the "rule of thumb" up. i have no clue where your 40% claim comes from, but its nowhere near accurate - id classify that as absurdly inflated to be honest. maybe try not to post conjecture/misinfo .. just wait for more people to run these turbos like you said.

edit - the reason most drag racing classes measure inducer is so that the turbo doesnt have to come apart for tech inspection... it would be highly unusual to expect racers to disassemble their turbos every morning for tech

edit2 - if you take those buschur results serious, and honestly believe a T3 undivided hta30r will wax a twinscroll efr... im wasting my time responding here.

 

Absolutely, I'd hope the overall failure rate is much lower - its a shame its hard to find more good results, I'm just going off what I've found... as I mentioned in that post. I didn't actually mean I thought the overall failure rate was that high, I shouldn't had put a number there. The point I meant to make is going by the amount of public failures the failure rate is unacceptable so far, regardless of the exact figures.

All I have to go on so far, I'd be happy to be proved wrong

 

I've said it before and I'll say it again, a GT30 turbine wheel has LESS inertia than the EFR 70mm turbine wheel. You don't even have to do any funky math, just LOOK at the pic above and its obvious... Plus the GTX wheels have much more impressive compressor maps than their EFR equivalents. As for the claimed compressor/turbine mismatch, the GT30 turbine was originally designed for a 76mm compressor wheel, so it can't be all that bad, besides - where do all these so-called rules of thumb come from? An HTA86 is another highly mismatched turbo on paper, yet nobody can deny that its one of the best currently available turbos for a high-powered 4G63...