[Closed] Borg Warner Efr Series Turbos

[Lithium]

I am betting pretty similar spool wise but I'd not be surprised if the EFR is running a little more boost - more so than anything because the GT wouldn't have been any point pushing any more through.

[SimonR32]

Yeah the only reason I ask is because the graphs look very similar to what would happen if you just boosted up the GT3582R

So it would be unfair to say one is better just because it's running more boost

[Lithium]

Of course, except the GT3582R was running apparently around 30psi all the way through - the EFR8374 was running less boost in the high rpm according to the owner. GT3582Rs aren't known to crack 700whp - some people will argue 650hp is more than you'd see at the hubs from one

[zebra]

Bringing this back up, instead of whoring the GTX thread.

Anyone rocking one of these yet?

After seeing the somewhat dissapointing results of the GTX garrets I hope these are better, otherwise I'll be slapping a $1000 Ebay T67-25g on the 1JZ lol

I think a 7064 would be mint on a streeter

[Lithium]

A lad over here is putting an EFR8374 on his RB30/26 GTR sometime in the pretty near future, I will update thread with results - I can see it being a couple of months yet just so I don't get spammed with queries on when I am going to update

[GTScotT]

So I thought I would take one of these into consideration.. Knowing that the turbo will give its best result on the higher right side of the compressor map, I took the 7076 into consideration to find that best results will be acheived at over 2 bar of boost.

Considering I want to run 98 ron and a factory standard long motor, I cannot see the advantage in these bloody billet compressor turbos.

The appealing point for me right now, is T4TSIW... This is making the prospects of using my T4TSIW 3576 in the garage a lot more appealing.. Maybe simply swap the CHRA for a standard 3540 item and see how it goes.

[Lithium]

People should stop perceiving the billet thing as whats responsible for the efficiencies being at higher pressure ratios, GTXRs if they get enough buyer volume will end up with cast compressor wheels - no doubt. I do feel that a lot of these things are just changing their bias to higher boost levels instead of evenly distributed flow, meaning that they're best suited for ~2litre engines - or two of them on a bigger engine.

They still have an advantage over the normal compressors, its just at high boost do they really shine.

[GTScotT]

Its not that I believe the billet factor to be responsible for the change in efficiency, its that I feel the design they wish to pursue (which is directly responsible for this character) is difficult to create in a cast compressor wheel.

I think they have moved to a billet wheel as a means to easily manufacture the said design whilst taking advantage of other benefits such as weight savings.

This is my personal thought on why they have gone to a billet wheel and obviously could be factually wrong, yet I would say the theory is as good as anyone elses.

While the possibility of these turbos still exceeding current tech at normal boost levels is valid and entirely possible, I believe turbos work best in all respects when pushed to the upper limit of their efficiency. Thus not giving me full faith in the turbo. I would rather run a 3076 at 20oddpsi than I would one of these, knowing these would shine at 30+

[Lithium]

The trick is these aren't a single trick pony, even if an EFR7670 flows no morebelow crazy boost levels (the S2000 with the GT3582R vs EFR8374 on 1bar still made more power everywhere with the EFR), its going to provide less exhaust resistance by having less weight and a pretty decent flowing turbine wheel - more response and less exhaust manifold pressure on an equivalent setup sounds good.

Then you get into the fact that a twin scroll setup will be so easy to get right with one, having a nicely formed wastegate flow back into the main exhaust stream sorted by the experts, no need to get or place a BOV or wastegates etc all work out as a mass of +s. I await the STI results before I get TOOOO excited (truth be told I am already fizzing at the bung) but I reckon even at the boost level I am running my car at, I'd end up with for all intents and purposes a faster car going to a TS EFR7670.... if I decided to be a nutcase and push 1.8bar through it then, who knows.

[zebra]

The trick is these aren't a single trick pony, even if an EFR7670 flows no morebelow crazy boost levels (the S2000 with the GT3582R vs EFR8374 on 1bar still made more power everywhere with the EFR), its going to provide less exhaust resistance by having less weight and a pretty decent flowing turbine wheel - more response and less exhaust manifold pressure on an equivalent setup sounds good.

Then you get into the fact that a twin scroll setup will be so easy to get right with one, having a nicely formed wastegate flow back into the main exhaust stream sorted by the experts, no need to get or place a BOV or wastegates etc all work out as a mass of +s. I await the STI results before I get TOOOO excited (truth be told I am already fizzing at the bung) but I reckon even at the boost level I am running my car at, I'd end up with for all intents and purposes a faster car going to a TS EFR7670.... if I decided to be a nutcase and push 1.8bar through it then, who knows.

i agree, these seem much better at lower boost than either the Presision Billet or GTX turbos.

Espesially hte Presision ones, which by the looks of all the results i've seen dont come alive till 2Bar.

The EFR turbos are designed with OEM in mind so appear to have a broader efficency range than the performance orientated GTX and Presision turbos

[Lithium]

The EFR turbos are designed with OEM in mind so appear to have a broader efficency range than the performance orientated GTX and Presision turbos

I suspect a lot of it is to do with the fact its not just a new billet compressor wheel of some description shoved onto the same old housings, core and turbine wheel. Here we have a fully re-designed unit, EVERYTHING is designed with raising the bar and imho it shows at least on paper. It will be interesting to see what happens when more people get to tune and drive setups running these turbos to see how good it really is.

Initially I thought Garrett were pretty cunning bringing out the GTX turbos just as the EFR hype started winding up - but it could end up backfiring if their best counter turns out to perform barely any different to existing units on the market.

[Legionnaire]

So I thought I would take one of these into consideration.. Knowing that the turbo will give its best result on the higher right side of the compressor map, I took the 7076 into consideration to find that best results will be acheived at over 2 bar of boost.

Considering I want to run 98 ron and a factory standard long motor, I cannot see the advantage in these bloody billet compressor turbos.

The appealing point for me right now, is T4TSIW... This is making the prospects of using my T4TSIW 3576 in the garage a lot more appealing.. Maybe simply swap the CHRA for a standard 3540 item and see how it goes.

I agree with the above post. I don't see myself pushung more than 20-22 psi down the factory engine's throat. This boost equals to 2.4-2.5 pressure ratios, at which EFR compressors look pretty ordinary even compared to vanilla garrett GTs, let alone new GTX. E.g. take a EFR7064, which is advertised to be a 550hp capable turbo with unrivalled compressor size vs. flow characteristics and is regarded as a direct GT/GTX3071's competitor:

True, it flows ~54 lb/min, but at what efficiencies (do I see two 60% lines on the map?) and, more important, at what PRs? Unless I want to run some 40 psi, there is no 54 lb/min flow, and since RB25 is no diesel engine, I am pushing 40 psi in. At my intended PRs, around 2.5, it flows only 48-49 lbs with ~60% efficiency.

On the other hand, G's GTX 71mm compressor

delivers 50lb/min at as low as 1.9 PR, and at desired 2.5 PR flows up to 56lb/min and delivers 50lb/min with 70+% efficiency, so for my particular application (factory bottomed RB25 Neo, possible poncams, 500 crank HP on 98RON, boost pressure no higher than 22 psi) turbo with a GTX 71mm compressor is better than 70mm BW one. Garret 60mm turbine is also known to be supporting this power figue, so no worries with the choked top end either.

Sure, you may ask "why use 7064, go for 7670 instead". Good question, and the answer, as I see it, is following: I will happily go get me a 7670 but only if it proves to outspool GTX3071.

BW 76mm compressor also doesn't show any impressive flow figures at 2.5 PR:

- this is 51lb/min at 65% efficiency, not as bad as 70mm, but still worse than GTX 71mm. Also its flow at lower PRs is pathetic - at 1.95 PR it flows only 42 lb!

All in all, although I do not deny huge effort invested in EFR development, and drool over lightweight TiAl turbine wheels and shafts, for the crowd that likes to achieve as much as they can with bolt-ons and without upgrading internals, EFR turbos currently seem to be less than optimal choice.

I also don't think GT/GTX3582 vs EF 8374 is a fair comparison, as those turbos were designed around different concepts and with different power goals. The more fair comparison would be EFR 8374 vs. T04Z - 83.5mm vs. 84mm compressor and 74mm vs. 74mm turbine.

[zebra]

May I ask why you dont want to run more than say 22psi.

Boost is just manifold pressure, so if you need to run 25psi to get the airflow needed to make the power you want than do it.

You might need to run a real intercooler and not some china POS and good quality hose clamps/joiners.

I would have no problem running up towards the top right of the comp map providing good support systems in place.

500HP is the upper limit of a stock internal RB, so no matter what boost you run its going to be a knife edge state of tune for the engine.

[Legionnaire]

Is R34 GTR intercooler considered shit? Ok, I know it isn't, but is it sufficient for 320rwkw goal? That's the one I use now.

I'm somewhat worried about high chamber pressures as I'm not ready to reduce CR and put in forged pistons just yet. I believe too high chamber pressure is what breaks ring lands on factory pistons. True, knock can do nasty things to chambers, as can preignition, both knock and preignition can be eliminated by proper tune and can be monitored with rather simple and affordable sensors, however chamber pressure data can not be acquired without special and ultra expensive equipment, but can wreck bearings and pistons just as easily as the former two.

[Lithium]

Sure, you may ask "why use 7064, go for 7670 instead". Good question, and the answer, as I see it, is following: I will happily go get me a 7670 but only if it proves to outspool GTX3071.

I also don't think GT/GTX3582 vs EF 8374 is a fair comparison, as those turbos were designed around different concepts and with different power goals. The more fair comparison would be EFR 8374 vs. T04Z - 83.5mm vs. 84mm compressor and 74mm vs. 74mm turbine.

You seem to be picking comparisons/expectations which handicap the BW. Why would a 7670 have to outspool a GTX3071R to be worthy, when its a fair bit bigger turbo? We can't comment too much here, but I am interested to see if the impression one would get from the maps is different from actually proves to happen when the EFR7670 gets on the dyno for comparison with GTX3076R.

In terms of EFR8374 vs GT3582R, the 8374s have been found to spool similar or better despite being capable of more power. If you think that they aren't a fair comparison then isn't that just stating that the GTX is out of its league? A T04Z would get destroyed in terms of spool against an 8374

[badhairdave]

Found link to a 6258 on sr install

http://nissanroadracing.com/showthread.php?t=2287&page=8

Will be interesting to see how it compares to a disco/2871.

Unfortunately they don't bolt up to a std low mount manifold due to physical size as i suspected....

[NYTSKY]

Is R34 GTR intercooler considered shit? Ok, I know it isn't, but is it sufficient for 320rwkw goal?

I know of a 32GTR with a 34GTR intercooler making 385awkw.

[Legionnaire]

You seem to be picking comparisons/expectations which handicap the BW. Why would a 7670 have to outspool a GTX3071R to be worthy, when its a fair bit bigger turbo? We can't comment too much here, but I am interested to see if the impression one would get from the maps is different from actually proves to happen when the EFR7670 gets on the dyno for comparison with GTX3076R.

Hmm, actually I'm just trying to pick a turbo with a particular set of input parameters, of which decent spoolup for a given power level and sane boost pressures have highest priority. For a given power requirement, in the above case 500bhp or ~320wkw was chosen because 200hp/litre seem to be quite a common goal these days, I have to choose from EFR7064, EFR7670, and X3071/X3076 (as well as holset HX/HY35, some airwerks, mitsu TD06-25G, etc. but they all have worse response than garrett and EFR turbos), and of those 4 the X3071 seems to be the best, but no test data to confirm/diprove this yet. Sure, for different set of input parameters different turbo would be the pick - that's standard turbo matching, isn't it?

In terms of EFR8374 vs GT3582R, the 8374s have been found to spool similar or better despite being capable of more power. If you think that they aren't a fair comparison then isn't that just stating that the GTX is out of its league?

Impressive for the turbo that big. Was it with a TS or SS housing? If 8374 provides response in between GT30 and GT35 but flows like T04Z I may reconsider my turbo plans, amazing turbo!

Full boost at 5500 is funny though.

I know of a 32GTR with a 34GTR intercooler making 385awkw.

Excellent, thanks for info.

UPDATE: I thought somebody should post it: EFR Turbo Technical brief.pdf

Edited February 19, 2011 by Legionnaire

[Lithium]

Impressive for the turbo that big. Was it with a TS or SS housing? If 8374 provides response in between GT30 and GT35 but flows like T04Z I may reconsider my turbo plans, amazing turbo!

Full boost at 5500 is funny though

Owner swapped from .82 GT3582 to internal gate .83 EFR8374. Gained power pretty much everywhere on same boost, pretty sure results were posted in this thread.

[wolverine]

I'm somewhat worried about high chamber pressures as I'm not ready to reduce CR and put in forged pistons just yet. I believe too high chamber pressure is what breaks ring lands on factory pistons.

Surely during combustion in-cylinder pressures are much higher than manifold pressure....like 50 to 100 times higher.