[Closed] Borg Warner Efr Series Turbos

[bri73y]

Hi Geoff,

I noticed there's a new rear for the 6258's. Has there been any testing done against the original .64 rear ??

Would be interested to hear the resulting differences between the two...

(is it wrong to say I'm getting bored with only 500kw..??)

lol - in all seriousness, the singles have their place (got one on my car) but twin EFRs are next-level

[SimonR32]

No.

There is a graph from very early on in the tuning process. 10 psi at 4500?

4th gear runs by the looks!

Handy result, would be interesting to see VCT vc non-VCT

[Full-Race Geoff]

I noticed there's a new rear for the 6258's. Has there been any testing done against the original .64 rear ??

Would be interested to hear the resulting differences between the two...

(is it wrong to say I'm getting bored with only 500kw..??)

hey John, have not done any back to back 0.64 vs 0.85 on an RB26 yet. built RB26's seem to prefer larger rear housings (within reason) so this is something brett was planning to do on his R34 in the next couple of months. Most of our higher power RB customers seem to go with the 6758 and 7163

it appears it was done in 3rd.. could an 8500rpm readline be correct? that means spooling (10psi) around 4500 and full boost (27psi) at 5800rpm

We typically see 1bar / 15psi around 3500rpm on 2.6L engines with the 8374. I expect we'd be flamed if our "response" based 62mm single turbo was spooling that late on an RB with vcam (10psi @4500)

[Piggaz]

Hi Geoff,

I noticed there's a new rear for the 6258's. Has there been any testing done against the original .64 rear ??

Would be interested to hear the resulting differences between the two...

(is it wrong to say I'm getting bored with only 500kw..??)

lol - in all seriousness, the singles have their place (got one on my car) but twin EFRs are next-level

Chuck up your graph again mate?

What pressure are you running to net 500 kW?

[burn4005]

We typically see 1bar / 15psi around 3500rpm on 2.6L engines with the 8374. I expect we'd be flamed if our "response" based 62mm single turbo was spooling that late on an RB with vcam (10psi @4500)

That's a fantastic result then, I was just having trouble reconciling the speed axis on that to RPM mathematically...

an EFR8374 is definately on the cards for me in the next year or so. Having Matchbot and all the turbo maps available is definitely a huge plus for the Borg. I can't make an educated decision on a 6262. its just "yea mate they're good for an RB26"..

I'm yet to stretch out my 2530s on E85, but I can't see them being as good.

Edited September 14, 2015 by burn4005

[bri73y]

This goes back a few years now, I don't have a recent one saved anywhere as the result is always similar.

30spi dropping off, the larger rear housings might just be worth a try..

Alternatively now that I have my chassis all sorted (and bank account drained) I can probably look to go up to bigger twins or large single as I'm confident the car will now handle the extra power.

Chuck up your graph again mate?
What pressure are you running to net 500 kW?

[NismoSTune]

I too am curious how the .64 and .85 compare in general. I have the .64 and would consider .85 if I didn't get enough out of the .64 but going with 6758 or 7163 twins sounds nuts.

too late to convert for me now.

[omnigear]

So a 7670 would be sufficient to get at 600hp on e85 then?

[Full-Race Geoff]

I too am curious how the .64 and .85 compare in general. I have the .64 and would consider .85 if I didn't get enough out of the .64 but going with 6758 or 7163 twins sounds nuts.

too late to convert for me now.

i like 0.64 for street cars, but im into spool, torque and power band (im an engineering nerd). for a real race car that has a racing transmission and chassis, spool is not as important as outright power. 7163 appears to be slightly more surge resistant than 6758 so that is a plus for 7163 twin installs.

Having Matchbot and all the turbo maps available is definitely a huge plus for the Borg. I can't make an educated decision on a 6262. its just "yea mate they're good for an RB26"

great to hear you like the matchbot and data that is provided! i continue to learn all the time using that tool

dyno677hp.jpg

This goes back a few years now, I don't have a recent one saved anywhere as the result is always similar.

30spi dropping off, the larger rear housings might just be worth a try..

Alternatively now that I have my chassis all sorted (and bank account drained) I can probably look to go up to bigger twins or large single as I'm confident the car will now handle the extra power.

swapping to stiffer IWG actuators on your existing 6258s may help carry boost in the higher RPM. turbosmart makes a quality actuator, just be aware it has less stroke than the standard BW and only 2mm preload is appropriate.

moving up to twin 7163s is worth consideration if you have the engine/displacement/head and really want to handle more power - its a direct fit to your 6258 install

So a 7670 would be sufficient to get at 600hp on e85 then?

7670 is really a 530-550hp turbo. For a true 600hp the EFR 8374 is the call. Internal WG with a stiff actuator gets it done nicely on E85 and a simple setup

Edited September 17, 2015 by Full-Race Geoff

[NismoSTune]

So on the topic of the efr wastegates I've been hearing more feedback from local tuners who struggle to have no boost creep or have unstable boost at whatever Desired setting and blade the efr wg. The builder/tuner is now pushing to change to the turbo smart actuators stating that they are just right. Why isn't anyone else reporting these issues? Also looks like it's a very tight fit fit with the efr actuators, will the turbosmart fit twins on the gtr?

As for turbo selection, I wasn't going after big power but my build took a few turns which is why I asked about the larger housings. I am after the low and mid range power.... I did not select the cams.

I run:

Tomei 2.8 short block (n1)

Tomei +1mm valves along with all their head upgrades and 290 deg 11.5mm lift cams

Ppg 1-5 helidog gear box and so on

So obviously it's too late to try and sell my turbos in favor of larger ones (hough they are new, people rarely buy 2 efrs at once) but I'm also not after huge power. So I should be OK with the smaller 6258 then...

I'd be happy with 600whp.

Edited September 17, 2015 by NismoSTune

[Full-Race Geoff]

I am after the low and mid range power...I'm also not after huge power. So I should be OK with the smaller 6258 then...I'd be happy with 600whp.

i believe 6258 0.64 is probably the perfect choice for you. Im running these turbos as twins on my current 3.5L v6 project. The turbosmart actuators will fit just fine.

We've seen excellent results with the OEM borgwarner stiff wastegate actuators -- up to 28psi. This is how borgwarner designed them and it works quite well. The original intent was to release a stiffer "higher boost actuator" that would go to 40psi. however the turbosmart options works very well and bw chose to focus on some other alternatives you may see at sema this year.

for more IWG control or for boost levels far beyond 28psi then the turbosmarts are an excellent choice. I personally worked with Jon at BW and we used alicat scientific equipment to provide turbosmart with our input on how to tweak and refine the IWG dual port before public release. They took our input into consideration and produced a nice quality gate. it is not at all mandatory, but it does have its place in the market

[NismoSTune]

odd that this tuner would have nothing but problems steadying any IWG from EFRs...

I have the stiff cans yeah.

Edited September 18, 2015 by NismoSTune

[Full-Race Geoff]

^^every setup is different, engines, manifolds, turbos, a/r it all has an effect. if the stiff bw canister isnt enough, then turbosmarts unit on a 3 port or 4 port can do the job

[burn4005]

Any dual port actuator on a 4 port solenoid should be able to hold it shut.

[NismoSTune]

2 dual port controllers would be annoying on twins

[Full-Race Geoff]

twin turbo setups should be plumbed the same as twin wastegate setups - one solenoid, two actuators

[HarrisRacing]

That's a fantastic result then, I was just having trouble reconciling the speed axis on that to RPM mathematically...

an EFR8374 is definately on the cards for me in the next year or so. Having Matchbot and all the turbo maps available is definitely a huge plus for the Borg. I can't make an educated decision on a 6262. its just "yea mate they're good for an RB26"..

I'm yet to stretch out my 2530s on E85, but I can't see them being as good.

My turbo manifold shipped today. I should have results of a pretty stout stroker 2.75L with ported head, +.5mm valves, springs, cams, hypertune V2, etc shortly on a 6boost manifold and 8374 EFR with .92 IWG setup.

I'd say I should have dyno results within 2 months max. I have had the "two steps forward, one back" constantly on my project so it's taken me forever waiting on new parts and fabbing stuff.

[nicknack]

I never had issues with boost control on my T4 IWG 7163. Boost was always easy to control, but the tuner and I went for a creeping boost curve to give a nice powerband.

This is a 9.5:1 compression sr20vet (still 2L) by the way. Intake cam was advanced 4 cam degrees and the exhaust retarded 1 or 2. I will go again for a retune with +2 intake and - 1 exhaust which should bump power up a bit. I'll also fab up a 3.5" down/front pipe.

This dyno reads pretty low compared to most in Sydney. Slight dip in the power curve was because of a slight misfire. It made a few extra KW in a later pull (346kw) but i'm pretty happy with how it drives considering it makes this much power. The tuner was just so impressed and said this was way ahead of a normal sr22det with a gt3076r he tuned.

[NismoSTune]

Geoff you mean 2 boost controllers and 2 waste gates... right? Not 1 and 2?

Each turbo has its own solenoid is what I was told when I bought the twins, not 1 solenoid that splits to 2 turbos...

Edited September 24, 2015 by NismoSTune

[burn4005]

No, two boost controllers will give instability as the integrals will fight each other. One solenoid goes to the two actuators. They should have the same preload so their opening characteristics are the same. Usually you wind up an air compressor regulator and make sure they move in unison.