Borg Warner EFR Series Turbo's V 2.0

[RICE RACING]

12 minutes ago, Piggaz said:

All the comparisons? What have you compared? What did you find?

map/tip relationship to

• air flow
• power loss
• EGT
• pumping losses
• acceleartion
• various map levels 1700mB to 2900mB
• knock

Also tested and still testing long term durability

• turbine speed limits

This is done on OS315 RB Tomei built engine in R34GTR

What I have found is 'interesting' and not normally shared on internet (not that I looked that hard) or found  easily, I think anyone serious does not post these bits especially if they are pushing limits as we are but I can let Geoff answer further.

Regardless to say you will see some items are not as they are claimed to be which is not unusual given the types of people in the after market world and the equipment they are using, not meant to be a put down its just a fact of life. 

 

:)

[RICE RACING]

Testing EFR9180 to its 'limits' while still keeping response as a priority, lots of other incidental items like anti lag on gear shifting using OEM gearbox too.

[RICE RACING]

We have done over 50,000+ engine cycles at on-load which is on average 85% or greater of the peak power, so its indicative of a proper durability test, to date over 18 minutes on load. Once some more proper testing is done I'll see if owner wants to unleash some of the findings here, first steps though are to prove the durability, not into drags (seconds) or one lap wonders (a few minutes), rather we are talking hours

[Lithium]

14 hours ago, RICE RACING said:

We have done over 50,000+ engine cycles at on-load which is on average 85% or greater of the peak power, so its indicative of a proper durability test, to date over 18 minutes on load. Once some more proper testing is done I'll see if owner wants to unleash some of the findings here, first steps though are to prove the durability, not into drags (seconds) or one lap wonders (a few minutes), rather we are talking hours

That makes for some good reading as is, thanks for sharing - lines up relatively well with how I kind of picture things.  Obviously a 1:1 pressure ratio across the engine is ideal from the stand point of something that doesn't have to deal with transient conditions (drags, steady state etc) but I definitely feel that letting a bit of drift upwards in EMAP to ensure response etc is not the worst thing in the world.  Hell, it seems only to be a semi recent thing where people start shunning anything over 1:1 for road/track cars when previously it was usually a target for drag cars.   These days it gets more plausible because turbos etc are so much more efficient that you can float around 1:1 and still have fairly decent response.

Obviously there is no one size fits all as it depends on temperatures etc etc etc, but I think a lot of people would shxt if they knew what most factory turbo cars, rally cars, and most serious race cars have run in terms of IMAP vs EMAP.   

In @Piggaz case however, it sounds like the bigger housing is not likely to really cost anything which is going to compromise his driving experience much - the 1.05 EFR8374 sounds like a response beast, and having surge issues down low is a nightmare I've had to deal with in the past and I can associate with wanting to try stuff to get rid of it... especially if part of your buzz is trying new things and learning from it.   I'd probably have just gone a 1.05 EFR9180 to reslve it, but there is no secret I have a raging one for those turbos haha.

 

[Lithium]

PS Mr @RICE RACING, if it's not inappropriate to ask - how does the EFR9180 hold on up high on the 3.2?  I have a mate having issues with his 9180 RB32 build, it's falling on it's face at 6000rpm - like power is rolling over hard.  He changed from 1.05 to 1.45 and it's made no difference at high rpm, and it happens at all boost levels.

I'm not currently at all convinced it's the turbo though some sound like they're suggesting it is.  It is also struggling to make the power it should be - actually barely making any more than a good EFR8374 setup would, imho.

[RICE RACING]

1 hour ago, Lithium said:

PS Mr @RICE RACING, if it's not inappropriate to ask - how does the EFR9180 hold on up high on the 3.2?  I have a mate having issues with his 9180 RB32 build, it's falling on it's face at 6000rpm - like power is rolling over hard.  He changed from 1.05 to 1.45 and it's made no difference at high rpm, and it happens at all boost levels.

I'm not currently at all convinced it's the turbo though some sound like they're suggesting it is.  It is also struggling to make the power it should be - actually barely making any more than a good EFR8374 setup would, imho.

In this cars case (and all of them I run) we use advanced phase and anti phase capsule control on the wastegate/s. I think this is a big part to it as even in the rotary engines I do lots of others report the same symptom of power drop off, common problem it seems on EFR turbo's?

Here is the engine power and torque derived (take it for what you will) but in reality it does 100kph to 200kph in ~4.951 seconds using 3rd and 4th gear and long G equivalent @ 200kph of Dave's VQ35 R32 GTR on twin EFR's

Power and torque (shapes)

[RICE RACING]

One of the biggest things for lack of performance with these types of engines (6cyl) is the way the spool up an engine (not well) and this is shown up when you are changing gears. This is why least on this combination of engine and turbo I did not want to use a larger turbine housing personally, I advised strongly against it.

You can see in this interim test below you are looking at a point where there is inclusive of lifting off accelerator and going back to 100% that the turbocharger takes about 1.5 seconds to go back to the target pressure. The end effects on vehicle performance is significant indeed. I get around this by using essentially anti lag effect (demonstrated below), there is no transient delays, remember this is a 1.05AR turbine housing set up on a larger than normal engine, FYI we tested this on the standard RB26 and this turbo was just too large, nice power but shit performance in real world.

You can get amazing performance on the OEM 6 speed syncro box, just have to use all the tools in the ECU but its tricky cause if you don't have all of the strategies (turbo speed control for example) its easy to break the turbine, we are still on the original one :)

2nd to 3rd gear (keep in mine with this level of performance) it pulls through say third in under 1.5 seconds, so when you look at transients on gear shift starting mid 6k to high 8.4k rpm then everything is amplified when you are considering response, what works on a dyno or in 4th gear on road will not work when accelerating 1st,2nd,3rd on the street.... This is why some 'really powerful cars' are nuggets in the real world. It's all about the average power, not just in a dyno sheet loaded in one gear but actually when accelerating through the gears, I think lots of people miss this basic point.

Normal

Gas turbine effect (no transient losses)

 

[Lithium]

10 minutes ago, RICE RACING said:

It's all about the average power, not just in a dyno sheet loaded in one gear but actually when accelerating through the gears, I think lots of people miss this basic point.

 

I think most people seriously interested in EFR turbos are interested in them because they don't miss that basic point  

[RICE RACING]

Just now, Lithium said:

I think most people seriously interested in EFR turbos are interested in them because they don't miss that basic point  

True, I guess we are taking it one step further? and there is massive gains to be had when then looking at the housing option and other parts I mentioned above (forgetting sequential trans for a second, though they also suffer from same effects looking at the ~80ms on average power cut) its amplified in something with short gearing like the R34 6 speed. We are talking on an incremental of 100kph to 200kph with just one gear shift of around 1 second, which is significant....

 

So you go full circle without sounding like a know it all on the internet :) this 'advice' of map/tip of 1.000 on full power is a joke honestly I'd hate to drive it, would be good at 300kph though :P

[Lithium]

4 minutes ago, RICE RACING said:

True, I guess we are taking it one step further? and there is massive gains to be had when then looking at the housing option and other parts I mentioned above (forgetting sequential trans for a second, though they also suffer from same effects looking at the ~80ms on average power cut) its amplified in something with short gearing like the R34 6 speed. We are talking on an incremental of 100kph to 200kph with just one gear shift of around 1 second, which is significant....

 

So you go full circle without sounding like a know it all on the internet this 'advice' of map/tip of 1.000 on full power is a joke honestly I'd hate to drive it, would be good at 300kph though

Yeah flat shift and other antilag strategies are all awesome as well, and given @Piggaz has a sequential with flatshift etc also - I suspect it's not going to be the worst.  I guess it's a shame he doesn't have transient  (like off/on versus gear shifting) data from prior to the 1.05 as that's probably what will suffer the most on with the change to that 1.45 housing.
 

[RICE RACING]

7 minutes ago, Lithium said:

Yeah flat shift and other antilag strategies are all awesome as well, and given @Piggaz has a sequential with flatshift etc also - I suspect it's not going to be the worst.  I guess it's a shame he doesn't have transient  (like off/on versus gear shifting) data from prior to the 1.05 as that's probably what will suffer the most on with the change to that 1.45 housing.
 

He will be fine ?

[Full-Race Geoff]

21 hours ago, RICE RACING said:

One of the biggest things for lack of performance with these types of engines (6cyl) is the way the spool up an engine (not well) and this is shown up when you are changing gears...when you are considering response, what works on a dyno or in 4th gear on road will not work when accelerating 1st,2nd,3rd on the street.... This is why some 'really powerful cars' are nuggets in the real world. It's all about the average power, not just in a dyno sheet loaded in one gear but actually when accelerating through the gears, I think lots of people miss this basic point.

  agree 100%.  thank you for posting up Peter!

21 hours ago, RICE RACING said:

 this 'advice' of map/tip of 1.000 on full power is a joke honestly I'd hate to drive it, would be good at 300kph though

when i was younger and had less experience, i also thought the 1.00 target was a good idea.  now i understand peak turbine efficiency is typically found around the 1.00 a/r range.  the larger a/r will flow more with a loss in turbine efficiency (counter intuitive i realize).  the tradeoff is transient response, at least for a radial flow turbine

Edited June 14, 2018 by Full-Race Geoff

[RICE RACING]

On 6/15/2018 at 7:06 AM, Full-Race Geoff said:

  agree 100%.  thank you for posting up Peter!

when i was younger and had less experience, i also thought the 1.00 target was a good idea.  now i understand peak turbine efficiency is typically found around the 1.00 a/r range.  the larger a/r will flow more with a loss in turbine efficiency (counter intuitive i realize).  the tradeoff is transient response, at least for a radial flow turbine

Hey Geoff,

>23 minutes on load and >68,000 engine cycles proves its no one hit wonder, only 19 and 1/2 hours to go Car is getting fitted up with Alcon 6 pot brake upgrade and the fat heap of shit just wont stop when doing repeated tests (the Datsun is no Mazda!), as we don't use parachutes hahaha. Customer is happy though which is main thing > http://www.riceracing.com.au/rides.htm

Then its time for the final solution, the twin EFR kit. I am however quite impressed with the level of over engineering in the EFR9180, it can take some abuse! biggest issue with it though is not really compatible with a 6cyl engine (or any single turbo for that matter at this power/performance level) in a true street car application, as we discussed at length There is some merit for not only dog engagement but more importantly more correct gear ratio's, I always said a turbo engine especially does not ever need narrow spaced NA power challenged rpm drops 1:1 5th for example, and there are many proven examples where a 5 speed with 1:1 4th is a superior set up, but that is an argument for another thread I guess? With the 1.05A/R and this power level even given the 'EFR' attributes it still is lacking in single turbo form, so that is why I will steer him towards the twin's, more power, with more transient response.

[Lithium]

1 hour ago, RICE RACING said:

Then its time for the final solution, the twin EFR kit. I am however quite impressed with the level of over engineering in the EFR9180, it can take some abuse! biggest issue with it though is not really compatible with a 6cyl engine (or any single turbo for that matter at this power/performance level) in a true street car application, as we discussed at length There is some merit for not only dog engagement but more importantly more correct gear ratio's, I always said a turbo engine especially does not ever need narrow spaced NA power challenged rpm drops 1:1 5th for example, and there are many proven examples where a 5 speed with 1:1 4th is a superior set up, but that is an argument for another thread I guess? With the 1.05A/R and this power level even given the 'EFR' attributes it still is lacking in single turbo form, so that is why I will steer him towards the twin's, more power, with more transient response.

Interesting, more power seems like a no brainer - but you expect some improvement in response as well with the twins?  I am assuming you're talking at least EFR6758 size?

Please share results if you do it, if there is any "cake and eat it too" solution over the EFR9180 on an RB I'd be quite keen to see it - but I definitely don't have anywhere near the confidence that the twin kits will deliver to suggest someone change... but in data we trust.

[RICE RACING]

5 hours ago, Lithium said:

Interesting, more power seems like a no brainer - but you expect some improvement in response as well with the twins?  I am assuming you're talking at least EFR6758 size?

Please share results if you do it, if there is any "cake and eat it too" solution over the EFR9180 on an RB I'd be quite keen to see it - but I definitely don't have anywhere near the confidence that the twin kits will deliver to suggest someone change... but in data we trust.

It's already out there, Indy car, every type of V6 (sans regulated current F1 with MGUH). I don't know of any serious race engine (6cyl or greater) since the mid 1980's that runs a single turbo where low gear high rpm per second 'acceleration' response is as important as top/high speed power production.

Will use the Indy car 7163 set up, similar to this but in IWG for simplicity and cause we have zero issues running maximum boost at all rpm with advanced phase and anti phase capsule control in Life Racing based ECU.

While I don't have the polar moment of inertia specs I am sure based off the Indycar experience (Honda using 1 x 9180 then going to 2 x 7163's) that its much less than half, and given half the motor drives each turbine/compressor/shaft/seals drag etc its a net big win on response..... If people are interested I can put up the issue I highlighted where you just do not get this on the current single turbo install despite running a true twin gated 'split pulse' exhaust manifold, the 6 cyl engine just does not harness this well at all in my experience, and its shown up on a 1-2-3-4-5 gear run at full throttle

 

[Lithium]

On 6/22/2018 at 9:45 PM, RICE RACING said:

It's already out there, Indy car, every type of V6 (sans regulated current F1 with MGUH). I don't know of any serious race engine (6cyl or greater) since the mid 1980's that runs a single turbo where low gear high rpm per second 'acceleration' response is as important as top/high speed power production.

Will use the Indy car 7163 set up, similar to this but in IWG for simplicity and cause we have zero issues running maximum boost at all rpm with advanced phase and anti phase capsule control in Life Racing based ECU.

While I don't have the polar moment of inertia specs I am sure based off the Indycar experience (Honda using 1 x 9180 then going to 2 x 7163's) that its much less than half, and given half the motor drives each turbine/compressor/shaft/seals drag etc its a net big win on response..... If people are interested I can put up the issue I highlighted where you just do not get this on the current single turbo install despite running a true twin gated 'split pulse' exhaust manifold, the 6 cyl engine just does not harness this well at all in my experience, and its shown up on a 1-2-3-4-5 gear run at full throttle

Sorry I should clarify here, I am all for twin turbos on V6s - which is is a completely different engine bay configuration to a straight 6.   

With a straight 6, twins have to be kept on one side of the engine so they end up tripping over each other's plumbing as well as other things that need to occupy engine bay space - there seems to almost always end up being compromises made which could negatively affect the performance of the turbochargers... which may otherwise be capable of better performance.

With a V, a single turbo needs to be fed by exhaust gases from sets of exhaust ports facing in opposite directions on the opposite sides of a V - ending up with different, but still relevant compromises made in exhaust manifold and piping design over what would be ideal.

It's easier to make an optimal single turbo setup on a straight 6, and it's easier to make an optimal twin turbo setup on a V6 - the results usually seem to reflect that in practice, from what I've seen so far.   That aside, Indy cars spin to >11,000rpm so I'm not sure I'd refer to them and EFR7163s as a "low rpm" setup. 

Spinning a highly efficient 2.2litre engine to >11,000 sounds like a thing which could easily result in the EFR9180 choking the engine a bit, while I don't know at all for sure - it wouldn't surprise me too much if the gains, even if not power gains, are in adding width to the power band by holding power better at the higher rpm... not picking up more power at the basement, but "helping" at the lower end by allowing gearing/shift points which are better suited to the huge rpm they've built those motors to live in.  

If you have a comparison between an equivalent and a single "true split pulse" setup going through gears it would be really really interesting!  Definitely all keen for data which can help back up, or justify re-assessing my opinions.   It's all part of the mission to work out how to make things go better

 

 

[Dose Pipe Sutututu]

^ Unless you did what the Japs did in the early 90s with Cyl 1~3 on it's on own turbo, own FMIC and own plenum and repeat on Cyl 4~6.

Costly exercise for an Inline, Paul has a photo somewhere of this.

[RICE RACING]

The issue here is spinning the turbo, not the engine, its all relative, 2.2lt 11k or 3.2lt 7.5k, same thing at end of the day

There is no issue on the inlet side (japs or aftermarket in general is full of crack pot ideas/theory), the problem is totally in the exhaust phasing/scavenge which is negated with split pulse twin gate, but what is lost is stupid levels of internal volume and cross talk getting rid of any of the benefits of split pulse. So it all goes back full circle to lowering the K value of the rotating mass, and that is why twins is superior and always will be honestly.

Only thing left is to do a direct comparison of 7163 x 2 V's a single 9180, we will get to that eventually and if owner is happy will share here.

 

[afb312]

Efr7163 *2 at 60 lb/min vs a 9180 at 90 lb/min.

Combine this with better throttle response and packaging on the v6 and there is little to loose. In my opinion... 

Incidentally, 2.2 x 11k is approx 8 to 9k for a 2.8 or 3.0. 

My thoughts then turn to a full on twin 7163 being the better bet on an all out 3.2L Rb26. I haven't seen this demonstrated vs a similar build using a maxed out 9180. Particularly in the power, throttle responses and reliability. 

For most folk the big single is cheaper and a better package given that you have more than enough power to overcome grip on all corners until the end of third gear! Those were 255zr17 yokos on built 2.7 running a T78. 

Happy memories, but a pig for the throttle response....

On 3/14/2018 at 4:44 AM, MaximuSmurf said:

response

 

[Lithium]

1 hour ago, Dose Pipe Sutututu said:

^ Unless you did what the Japs did in the early 90s with Cyl 1~3 on it's on own turbo, own FMIC and own plenum and repeat on Cyl 4~6.

Costly exercise for an Inline, Paul has a photo somewhere of this.

Yeah, pretty sure we've all discussed this before - though it doesn't really fix the room for dump pipes, intake piping etc however it seems some people have got reasonable setups in there which may allow the turbos all the breathing they need.  The other trick with dual plenums (or twin turbos in general) is if you really are doing things properly and carefully, you probably should have separate load calculations done for each set of cylinders with it's own turbo.

@AdapTronic 's Modular ECU supports tuning separate banks where dual plenums are involved, dealing with the fact that even with a seemingly symmetrical mechanical setup will result in the two banks having different flow and different boost characteristics... which is potentially being a significantly bigger trap (which is more often overlooked) for making a tune which doesn't suit the engine perfectly than the typical concern people have tuning RBs where they give a little extra fuel to certain cylinders.

1 hour ago, RICE RACING said:

The issue here is spinning the turbo, not the engine, its all relative, 2.2lt 11k or 3.2lt 7.5k, same thing at end of the day

There is no issue on the inlet side (japs or aftermarket in general is full of crack pot ideas/theory), the problem is totally in the exhaust phasing/scavenge which is negated with split pulse twin gate, but what is lost is stupid levels of internal volume and cross talk getting rid of any of the benefits of split pulse. So it all goes back full circle to lowering the K value of the rotating mass, and that is why twins is superior and always will be honestly.

Only thing left is to do a direct comparison of 7163 x 2 V's a single 9180, we will get to that eventually and if owner is happy will share here.

 

Yeah absolutely, I wasn't saying that 3.2litre at 11,000rpm is the same as a 2.2 at 11,000rpm - though perhaps I got a bit hung up on the idea that 6500rpm is a lot of rpm when it's about the equivalent to a 3.2 at 4500rpm.   The concept I was getting at still applies, though - if you have a setup where the 9180 is rolling over at 7500rpm, a pair of 7163s might give you a fairly decent amount more usable rpm with less of a cost at low rpm.   So laggier, but the amount of torque spread at the higher end more than makes it up - you just shift you rpm range to the right a bit.

No issue on the inlet side in which setup?   I believe there is an issue with the inlets on low mount twins on an RB, but definitely not with a single on a V6 -  totally agreed with the exhaust being the big issue with a V6 single turbo setup, different problems but similar end result where a turbo doesn't perform as well as it could with a different environment.

 

1 hour ago, afb312 said:

My thoughts then turn to a full on twin 7163 being the better bet on an all out 3.2L Rb26. I haven't seen this demonstrated vs a similar build using a maxed out 9180. Particularly in the power, throttle responses and reliability. 

For most folk the big single is cheaper and a better package given that you have more than enough power to overcome grip on all corners until the end of third gear! Those were 255zr17 yokos on built 2.7 running a T78. 

Happy memories, but a pig for the throttle response....

 

Yeah gotta say, a serious full house 3.2litre with a pair of 7163s would be very interesting to see - the potential is strong if they can be made to work in unison with each other than the engine at the higher end of their power potential.  The way I view it however is that it's the equivalent to going to a bigger turbo setup that suits the higher needs better, a bit later in the rpm but potentially has a slightly better cost vs reward... which is often the case when you end up with a parts match that better suits the target.   It's not so simple as "one size fits all".