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I didnt dare say the BOOST threshold was the same, but I did talk about the character and used the word threshold loosely at best (read as a descriptive word).

They both shine to the same level at 4000rpm, with a similar curve (albeit one with less power within) prior to that point.

What I am saying is, they both boogie about the same when on power, and the period before being 'on power' is similar enough in character that it would not make for an enormous level of difference below 4000rpm.

While the boost is on earlier, I dont think that necessarily means very much when we have back to back direct comparisons of power and torque. I wont go into reasons why so not to offend you (read you know full well why and better than I do).

All in all considering the 'space age' materials used and the suggested market this size is aimed at its not all that special that it stands up and has a similar curve at a similar point to a 3076. It actually brings to light that a 3076 is still a good thing even on todays terms, with these special things out there.

If that hasnt cleared up whats bugging you about my comments then I dont know what will.

I think the real 'pro's' of the EFR series is more in transient response, considering the hype around their low-mass turbine wheels. Something which wouldn't really show on a dyno. Back in regards to the 7163, I can't remember if this has already been posted or not, but here is a link for a Perrin (read: Subaru engine) test showing a comparo on the 7163 with various other EFR and GT/GTX turbos. Great read and nice pretty pictures :D

http://blog.perrinperformance.com/borg-warner-efr-7163-test-and-tune/

Considering these were all done on a Subaru (which have, IMHO, a poor engine), and with a [relatively] low boost pressure, I think these are great results for a turbo that is capable of 300+rwkw. I mean, seriously, 15psi at 3K, and full boost (in this case 25psi) before 3.5K ... That's awesome.

I was also reading on the Honda s2K forums that the 7163 comes with an aluminium bearing housing; would this be for both weight/friction, or one or the other? As a street package on a stroked RB (2.8), with a big exhaust A/R in TS form (I think it is 1.01?), would be plenty responsive, while still being able to push 350+rwkw on E85. Add to that a nice shot of laughing gas, and you'll have one hell of a responsive 10 - 11 second car. (Or at least I hope)

Can't wait to place my order for one of these... *drools*

EDIT: Sorry guys, I can't seem to edit-out all the html type coding.. It wont save with the changes.. Any ideas? :S

EDIT EDIT: Ok, figured it out. Anyone else having troubles with the posting of posts?

Edited by Dajae
I sporadically have issues, yes - and the post you just put up was detail the exact results which GTScoTT was rambling about being not that impressive :)

I just looked back through the thread and realised you and GTScoTT were talking about this very same thing. Oops. Here I thought my little search in google was good.... lol.

Well, I find them impressive to a point... All things being considered. Not ground breaking, or a huge game changer, but still impressive.

They would have been game changing if there weren't already things fancier than the old GT-series etc already lurking around. Given that the actual response, not boost threshold which is meant to be the impressive things with these things... suggests that when you consider even the threshold looks good - they are potentially a VERY good thing.

whats the use of boost being on earlier if its not making more power too?

Im not saying its NOT making more power, im saying the amount more power isnt blowing me away. Regardless of when the boost comes on.

whats the use of boost being on earlier if its not making more power too?

I understand what you are saying.

If the response is as good as reported (like Lith is saying) and they don't grenade themselves they should be a good thing when more filter down here and we get more local results.

whats the Im not saying its NOT making more power, im saying the amount more power isnt blowing me away. Regardless of when the boost comes on.

The amount more power its making is pretty much proportionate to how much more boost its making. There is no magic, what bewilders me is that you have been far more impressed at far less impressive results.

i guess im more impressed when someone brings a total budget item to the market and it performs as it should, or when a little engineering company sprouts and continually raises the bar in many ways. that is impressive for me.

its a personal thing.. with the hype of the EFR and the technology involved, teething problems, wait times, etc.. id just have hoped they would blow anything current out of the water.

i guess ive set my own expectations lith, and unfortunately the EFR's arent living up to what I had personally hoped. thats all.

Fair enough. I set reasonably realistic expectations and will call a stick a stick - when the EFRs were looking shxt (failing etc) I called it that, but I also realise you get decreasing gains in this kind of area. Thats why the EFRs are clearly targetted at those who want to be the "top", its not going to be proportionally more awesome... its just going to be the thing that provides the edge. The whole technology hasn't been completely re-invented, they're just trying to use the best realistic features of existing technology to provide something high level to the masses.

Well that's the way I see it anyway.

The only turbo technology I can see possibly changing the way we look at things substantially in terms of turbo choice if it goes smoothly may be the Garrett Dual Boost stuff.

I agree your way of looking at it is more realistic, and probably entirely accurate. call me childish but i had higher hopes.

try jump on MSN soon, Id love to theorise with you over some PT5558 SR goodness. Have CP pistons at DET comp being match bored as we speak :)

Hi, Lith posted up my prelimiary tune graphs, Thought I would jump in here.

Well I'm pretty happy with the results of my EFR8374 so far, If I can get rid of some of the back pressure issues we are having we should be able to dial it up a bit more.

I have just got one of the Forge Motorsports Dual Port W/G's to try, Going dual port is generally recomended when high back pressure is a issue (We are struggling to keep the WG flap closed past 20psi), But if we dial up to 25ish psi we should get close if not on 500kw at the wheels on pump gas.

I'm yet to drive the car (It's at the body shop getting the guards pumped) but going from what the tuner has commented on it.....It should be awesome fun!

500+kW is a good effort! Plans for e85 at all? I have heard and read that the Forge Motorsports Dual Port Wastegate leaves quite a bit to be desired? Mostly off the suby forums and their experiences, nothing first hand..

No plans at this stage for E85, It is still a street car. If I could get it at the pump I would change.

What are they saying about the Forge W/G? Would be interested to hear?

I'll have to find the forum thread to reference properly, but IIRC, it had to do with the design and the way in which it holds pressure. Or rather, doesnt hold pressure.. Like a lot of things though, it had mixed reviews. Some swore by it, but the OP of that thread definitely wasnt happy. When I get to work I'll attempt to dig it up :)

I have no idea how that quick spool valve would be set up to actually work. They should only work with divided turbine housings and NON-divided manifolds. U can't just block off 3 cyliders until you're on full boost.

Does anybody know how this one would work and the benefit?

Edit: I think I get it now. The valve must direct the gas from one side into the other sie of the turbine housing.

Edited by bradsm87

yeah i would say the flap is actually the divider.. which blocks one side and opens the dividing area so gas can pass through to the other split.

nifty, but i dont like it lol.

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