[Closed] Borg Warner Efr Series Turbos

[DarKcyde]

The guy with twins is running 280 cams though, not exactly helping him spool early. The 8374 is a pretty big snail too.

[TheKeeper]

The boost leak would cover a bit, but they both still come on pretty late for their size

I dunno, maybe a 4th gear pull would have been a better indicator for that? The 6258's look like they could get you to 900hp according to BW, so they are not exactly small, but I agree with you based on this dyno chart.

Edited April 17, 2011 by TheKeeper

[Scooby]

are those dyno charts at the crank or at the wheels?

[TheKeeper]

are those dyno charts at the crank or at the wheels?

Mustang dyno at the wheels.

[Lithium]

I dunno, maybe a 4th gear pull would have been a better indicator for that? The 6258's look like they could get you to 900hp according to BW, so they are not exactly small, but I agree with you based on this dyno chart.

The turbo(s) have no idea which gear its in... a turbo won't spool differently just because a different gear is engaged, the rate the dyno allows the car to pull through the rpm will be the real teller.

EFR6258 is ~400hp rated I thought? Makes it comparable with GT-RS/Garrett "-10s" and given it looks like its full boost around or after 5000rpm, comparable to them in spool as well?

[TheKeeper]

The turbo(s) have no idea which gear its in... a turbo won't spool differently just because a different gear is engaged, the rate the dyno allows the car to pull through the rpm will be the real teller.

EFR6258 is ~400hp rated I thought? Makes it comparable with GT-RS/Garrett "-10s" and given it looks like its full boost around or after 5000rpm, comparable to them in spool as well?

Actually I have seen as much as 30whp increase and 400-500RPM faster spool in 4th gear vs. 3rd gear on Mustang dynos. Otherwise you could just run 1st gear and get the same results if you could strap the car down well enough, but the fact that the RPM's increase so quickly the turbos cannot be loaded properly for an accurate reading. I see in the in-car video it looks like the car spools from zero bar at 3,000RPM to 1.2 bar before it gets to 4,000 which tells me that on the road I bet those spool to 19psi by 4500RPM or so...

The 6258's are rated at 450HP each.

[Lithium]

I can't watch the vid as I am at work, but that sounds much more promising... like impressively so. Will check after work.

[Harey]

The turbo(s) have no idea which gear its in... a turbo won't spool differently just because a different gear is engaged, the rate the dyno allows the car to pull through the rpm will be the real teller.

So your saying a turbo will spool the same in 1st gear as 4th gear??? Not a chance.

[Lithium]

So your saying a turbo will spool the same in 1st gear as 4th gear??? Not a chance.

I have enough respect for you to realise if you made the post I did you'd not mean something retarded like that, even though you don't know me in person I'd like think by now you should be a bit wiser than that. Either that or I give you too much credit.

Most dynos control the rate a car goes through the revs, so while of course a car will generate a different amount of psi by xrpm in different gears on the road - if you run a car from 2500rpm to 7500rpm at a steady rate in 9s in 1st, 2nd, 3rd, 4th and then 5th gear on a dyno (if it were able to allow such a test) do you think the turbo will spool differently with all things otherwise equal?? And if so, please explain how?

[Harey]

I have enough respect for you to realise if you made the post I did you'd not mean something retarded like that, even though you don't know me in person I'd like think by now you should be a bit wiser than that. Either that or I give you too much credit.

Most dynos control the rate a car goes through the revs, so while of course a car will generate a different amount of psi by xrpm in different gears on the road - if you run a car from 2500rpm to 7500rpm at a steady rate in 9s in 1st, 2nd, 3rd, 4th and then 5th gear on a dyno (if it were able to allow such a test) do you think the turbo will spool differently with all things otherwise equal?? And if so, please explain how?

Prob came across a little harsh.

So your willing to assume that dynos will get this perfectly right? From the post by 'TheKeeper' above he states that just between 3rd and 4th gears on a mustang dyno is a 4-500rpm difference! I am yet to see this dyno behaviour and I prefer to see all dynos done in 4th gear to minimise the chance of inconsistencies.

I also remember having a 'discussion' with some users on here that stated that boost response will be the same in every gear and that load and speed had nothing to do with it. Might not have been you but I think we need to make sure that people new to turbos understand this so they dont choose the wrong turbo. It can be up to 1000rpm+ difference between 1st and 4th.

Same as I find it very misleading when some people use correction factors on their dynosheets and dont mention it. Makes it hard for people to do comparisons and make their choice of turbo. The more we can reduce the calculations performed by the dyno the better.

[Lithium]

So your willing to assume that dynos will get this perfectly right? From the post by 'TheKeeper' above he states that just between 3rd and 4th gears on a mustang dyno is a 4-500rpm difference! I am yet to see this dyno behaviour and I prefer to see all dynos done in 4th gear to minimise the chance of inconsistencies.

I also remember having a 'discussion' with some users on here that stated that boost response will be the same in every gear and that load and speed had nothing to do with it.

Definitely wasn't me, I posted a spool vid of my GT30R using different gears and load levels to help relate what it behaves like in different situations to people considering turbo options for an RB25 knowing full well it doesn't work that way.

I admittedly am not so familiar with dynos used in Oz but if you can't really count on a dyno being consistant in terms of acceleration rates, then there is no point at all in comparing dyno results to ascertain spool.

[TheKeeper]

I like to see 4th gear pulls as well as anybody on the dyno, but it's really not necessary when you plan to use the same gear and same dyno. (as long as it's not first or second as we all know) It's just very hot here and loading 4th gear is a long run. It will yield a faster spool and possibly more HP on most dynos, but not always worth it. I'm not sure Harey how you say you've never seen it other than maybe every pull you've been associated with has been 4th gear. Since we know the difference between 1st and 4th can be 1,000+ RPM, it stands to reason there is a difference between 1st to 2nd, 2nd to 3rd, 3rd to 4th, 4th to 5th....etc. The in car video shows only 1,000RPM range, but over a bar (1.2 if I remember my MFD's correctly) and it must be 4th or 5th gear because it spools quite a bit in that 1,000 RPM from 3,000 to 4,000. I can guarantee on that particular dyno a 4th gear pull would have shown faster spool and more HP.

[TheKeeper]

Definitely wasn't me, I posted a spool vid of my GT30R using different gears and load levels to help relate what it behaves like in different situations to people considering turbo options for an RB25 knowing full well it doesn't work that way.

I admittedly am not so familiar with dynos used in Oz but if you can't really count on a dyno being consistant in terms of acceleration rates, then there is no point at all in comparing dyno results to ascertain spool.

The ONLY thing I have ever used a dyno for was to ascertain whether or not certain modifications yielded a gain, and if so how much. Same dyno, same settings, same gear, different mods.

[rob82]

I have enough respect for you to realise if you made the post I did you'd not mean something retarded like that, even though you don't know me in person I'd like think by now you should be a bit wiser than that. Either that or I give you too much credit.

Most dynos control the rate a car goes through the revs, so while of course a car will generate a different amount of psi by xrpm in different gears on the road - if you run a car from 2500rpm to 7500rpm at a steady rate in 9s in 1st, 2nd, 3rd, 4th and then 5th gear on a dyno (if it were able to allow such a test) do you think the turbo will spool differently with all things otherwise equal?? And if so, please explain how?

You are spot on. It doesn't matter which gear you are in if the time for the ramp is the same the MAP vs RPM will be the same.

That being said up to a point the more torque you make the harder it is for the tyre carcass to transmit the torque to the roller. Once you get to this point the variation in dyno results can be massive. We have found that over 6000N of tractive effort on two 235's tyres is where the results can start to get spurious. On some big XR6T's we are making close to 12000N of tractive effort in 4th gear going out to 220Km/hr and I can tell you if I did two dyno runs back to back the power drops about 100rwkw and the roller tacho number - ie RPM/VSS ratio can change about 400rpm.

Also mustange dyno read high compared to Dyno dynamic dyno's.

Edited April 18, 2011 by rob82

[Full-Race Geoff]

Hi guys, great to see the discussion. Truth be told, that dyno is known as the lowest reading in Arizona. You may notice all our previous tests used dynapacks as our benchmark dyno since it is on-par with most other dynos that advertisements and forums reference. I planned to use the dynapacks but we had an opportunity to get these cars on this mustang dyno at a last minute's notice and we took it. The dyno pulls were all done in 3rd gear and we did not use a slow ramp-rate to increase load. it was a worst-case scenario dynoplot for "internet hype" but gives me the data I needed to see. The fuel used was arizona/california 91 octane which is very very poor fuel, it's actually 87 octane that is buffered with MTBE and ethanol to increase the knock resistance. I have a lot of experience with different RB turbos on my personal car and our customers cars, and now that ive had some time in each car, my input is as follows:

R34 w/ twinturbo EFR 6258 -- This car is an absolute blast to drive. I am a sworn single-turbo guy, but this combination is making me think twice about what turbo setup to use for my new car. Look at the in car video of 4th gear, you can see the stock R34 MFD has the boost gauge flashing red, hitting 1.2bar before 4000rpm. The owner of this car is an experienced on-track driver and long time skyline owner. He came from a pair of HKS 2530 twins to this EFR 6258 setup, on the same engine build. He comments that the 2530's did spool up a *tiny* bit earlier, but compared to the performance of the EFR's he doesn't miss anything about the 2530s. We are converting the car to run on E85 and will turn the boost up shortly. of course we will post those dynocharts also. This car is extremely driveable with great torque and comes back up on boost unusally fast between gear changes

R34 w/ single EFR 8374 -- I drove this car with the medium boost internal WG actuator and it felt good, but not great. We installed the high boost actuator (stiffer spring) and the turbo completely woke up. However its off again and i suspect a boost leak. Ive been absolutely swamped with some other jobs and had no time to focus on that car. I believe this is a bit large turbo for a stock head with this small of a camshaft, but this car also makes 1.2 bar before 4000rpm so it's still very driveable. I am eager to get this car sorted with some better flowing top end, and better fuel so we can turn the boost up. Will be sure to post results of this

[CaBS]

Really looking forward to some 7064 TS IW Dyno charts aswell as some single scroll ones on some different SR20 setups! Some 6758 SR20 numbers would be very interesting too! =)

[GTScotT]

After much reading, calculating and guessing I am going to say I believe a 7670 T4 IW on a 2.5L 6cyl would just about be completely loss-less. Loss less implying you would always have a turbo under your foot capable of supply enough airflow at all RPMs to match the motors want for flow.

Obviously I dont think a 650hp turbo would be standing up hard at 3000rpm like a GTRS, BUT, I do think this turbo would never have leave you waiting and all while seeing a neat 400rwkw.

Come tax return I am considering placing an order. If all goes to plan I will buy it with a low pressure actuator and a high pressure one so I can see how it responds to the factory 1JZ ecu. I have a strong feeling this particular sized turbo would almost feel like an OEM item at lower boost levels, after all I think this is what they were trying to achieve..

I could be wrong and may be better off with a 7064 BUT the map seems to plot better on the 7670, provided the larger exhaust wheel doesnt simply account for more lag.. Hopping Gamma-Ti and twin scroll will come to my 400rwkw party for that one!

[scandyflick]

Finalised my order for a 6258 through Full Race yesterday.

The wait is going to be killer, but it gives me time to sort out my new fuel system, and a clutch to cope with it.

It'll be going on an unopened SR20, running E85 through 1000cc injectors, and likely Brian Crower step 2 cams. I'll be aiming for the high side of 250rwkw with a conservative tune. I'd like to go higher, but a 25 box conversion doesn't quite make its way into the budget...

I'm ever so slightly excited...

And speaking of the guys at Full Race, f**king awesome blokes! Went out of their way to test fit a 6258 to a stock manifold equipped SR to check clearances and take a bunch of photos for me without any guarantee that I'd end up buying, super helpful and seriously cool guys.

[Lithium]

Nice - that should be pretty awesome! 6258 though? I'd have been pretty tempted to get a 6758 after spending that much, HKS GTRS are amazing on SR20s and the 6758 is still smaller so isn't exactly going to be laggy.

PS: I saw your avatar etc previously and thought nothing of it as I frequent the HevyDevy forum and you get used to that, but this is SAU - AWESOME I have Deconstruction and Ghost preordered haha

[Beer Baron]

nup he made the right choice. I have a fair bit of info (that I can't share just yet) on 6255 v 6258 vs 6758 but I can tell you the 6258 is the gun set-up in that range for what he wants to do with his SR20. All three have their optimum applications I'm sure but for that I think he's made the right choice.

I am thinking about trying a pair of them on my 2.7 GTR currently running twin HKS 2530s...